refactor(structure): move stuff out of main

4 files changed, 2126 insertions, 2108 deletions

diff --git a/src/main.rs b/src/main.rs
index 30f941c8..18f41d90 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,726 +2,17 @@
 mod tests;
 
 mod os_input_output;
+mod terminal_pane;
+mod pty_bus;
+mod screen;
 
-use ::std::fmt::{self, Display, Formatter};
-use std::cmp::max;
 use std::io::{Read, Write};
-use std::collections::{VecDeque, HashSet, BTreeMap};
-use nix::pty::Winsize;
-use std::os::unix::io::RawFd;
 use ::std::thread;
-use vte;
-use async_std::stream::*;
-use async_std::task;
-use async_std::task::*;
-use ::std::pin::*;
-use std::sync::mpsc::{channel, Sender, Receiver};
 
 use crate::os_input_output::{get_os_input, OsApi};
-
-use vte::Perform;
-
-struct ReadFromPid {
-    pid: RawFd,
-    os_input: Box<dyn OsApi>,
-}
-
-impl ReadFromPid {
-    fn new(pid: &RawFd, os_input: Box<dyn OsApi>) -> ReadFromPid {
-        ReadFromPid {
-            pid: *pid,
-            os_input,
-        }
-    }
-}
-
-impl Stream for ReadFromPid {
-    type Item = Vec<u8>;
-    fn poll_next(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-        let mut read_buffer = [0; 115200];
-        let pid = self.pid;
-        let read_result = &self.os_input.read_from_tty_stdout(pid, &mut read_buffer);
-        match read_result {
-            Ok(res) => {
-                if *res == 0 {
-                    // indicates end of file
-                    return Poll::Ready(None);
-                } else {
-                    let res = Some(read_buffer[..=*res].to_vec());
-                    return Poll::Ready(res);
-                }
-            },
-            Err(e) => {
-                match e {
-                    nix::Error::Sys(errno) => {
-                        if *errno == nix::errno::Errno::EAGAIN {
-                            return Poll::Ready(Some(vec![])) // TODO: better with timeout waker somehow
-                        } else {
-                            Poll::Ready(None)
-                        }
-                    },
-                    _ => Poll::Ready(None)
-                }
-            }
-        }
-    }
-}
-
-#[derive(Clone)]
-pub struct TerminalCharacter {
-    pub character: char,
-    pub ansi_code: Option<String>,
-}
-
-impl PartialEq for TerminalCharacter {
-    fn eq(&self, other: &Self) -> bool {
-        match (&self.ansi_code, &other.ansi_code) {
-            (Some(self_code), Some(other_code)) => {
-                self_code == other_code && self.character == other.character
-            },
-            (None, None) => {
-                self.character == other.character
-            }
-            _ => {
-                false
-            }
-        }
-    }
-}
-
-impl Eq for TerminalCharacter {}
-
-impl TerminalCharacter {
-    pub fn new (character: char) -> Self {
-        TerminalCharacter {
-            character,
-            ansi_code: None
-        }
-    }
-    pub fn ansi_code(mut self, ansi_code: String) -> Self {
-        self.ansi_code = Some(ansi_code);
-        self
-    }
-}
-
-
-impl Display for TerminalCharacter {
-    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        match &self.ansi_code {
-            Some(code) => write!(f, "{}{}", code, self.character),
-            None => write!(f, "{}", self.character)
-        }
-    }
-}
-
-impl ::std::fmt::Debug for TerminalCharacter {
-    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.character)
-    }
-}
-
-pub struct TerminalOutput {
-    pub pid: RawFd,
-    pub characters: Vec<TerminalCharacter>,
-    pub display_rows: u16,
-    pub display_cols: u16,
-    pub should_render: bool,
-    cursor_position: usize,
-    newline_indices: Vec<usize>, // canonical line breaks we get from the vt interpreter
-    linebreak_indices: Vec<usize>, // linebreaks from line wrapping
-    pending_ansi_code: Option<String>, // this is used eg. in a carriage return, where we need to preserve the style
-    x_coords: u16,
-    y_coords: u16,
-}
-
-const EMPTY_TERMINAL_CHARACTER: TerminalCharacter = TerminalCharacter { character: ' ', ansi_code: None };
-
-impl TerminalOutput {
-    pub fn new (pid: RawFd, ws: Winsize, x_coords: u16, y_coords: u16) -> TerminalOutput {
-        TerminalOutput {
-            pid,
-            characters: vec![],
-            cursor_position: 0,
-            newline_indices: Vec::new(),
-            linebreak_indices: Vec::new(),
-            display_rows: ws.ws_row,
-            display_cols: ws.ws_col,
-            should_render: true,
-            pending_ansi_code: None,
-            x_coords,
-            y_coords,
-        }
-    }
-    pub fn handle_event(&mut self, event: VteEvent) {
-        self.should_render = true; // TODO: more accurately
-        match event {
-            VteEvent::Print(c) => {
-                self.print(c);
-            },
-            VteEvent::Execute(byte) => {
-                self.execute(byte);
-            },
-            VteEvent::Hook(params, intermediates, ignore, c) => {
-                self.hook(&params, &intermediates, ignore, c);
-            },
-            VteEvent::Put(byte) => {
-                self.put(byte);
-            },
-            VteEvent::Unhook => {
-                self.unhook();
-            },
-            VteEvent::OscDispatch(params, bell_terminated) => {
-                let params: Vec<&[u8]> = params.iter().map(|p| &p[..]).collect();
-                self.osc_dispatch(&params[..], bell_terminated);
-            },
-            VteEvent::CsiDispatch(params, intermediates, ignore, c) => {
-                self.csi_dispatch(&params, &intermediates, ignore, c);
-            },
-            VteEvent::EscDispatch(intermediates, ignore, byte) => {
-                self.esc_dispatch(&intermediates, ignore, byte);
-            }
-        }
-    }
-    pub fn reduce_width_right(&mut self, count: u16) {
-        self.x_coords += count;
-        self.display_cols -= count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn reduce_width_left(&mut self, count: u16) {
-        self.display_cols -= count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn increase_width_left(&mut self, count: u16) {
-        self.x_coords -= count;
-        self.display_cols += count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn increase_width_right(&mut self, count: u16) {
-        self.display_cols += count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn reduce_height_down(&mut self, count: u16) {
-        self.y_coords += count;
-        self.display_rows -= count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn increase_height_down(&mut self, count: u16) {
-        self.display_rows += count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn increase_height_up(&mut self, count: u16) {
-        self.y_coords -= count;
-        self.display_rows += count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn reduce_height_up(&mut self, count: u16) {
-        self.display_rows -= count;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    pub fn change_size(&mut self, ws: &Winsize) {
-        self.display_cols = ws.ws_col;
-        self.display_rows = ws.ws_row;
-        self.reflow_lines();
-        self.should_render = true;
-    }
-    fn reflow_lines (&mut self) {
-        self.linebreak_indices.clear();
-
-        let mut newline_indices = self.newline_indices.iter();
-        let mut next_newline_index = newline_indices.next();
-
-        let mut x: u64 = 0;
-        for (i, _c) in self.characters.iter().enumerate() {
-            if next_newline_index == Some(&i) {
-                x = 0;
-                next_newline_index = newline_indices.next();
-            } else if x == self.display_cols as u64 && i <= self.cursor_position {
-                self.linebreak_indices.push(i);
-                x = 0;
-            }
-            x += 1;
-        }
-    }
-    pub fn buffer_as_vte_output(&mut self) -> Option<String> {
-        if self.should_render {
-            let mut vte_output = String::new();
-            let buffer_lines = &self.read_buffer_as_lines();
-            let display_cols = &self.display_cols;
-            for (row, line) in buffer_lines.iter().enumerate() {
-                vte_output.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", self.y_coords as usize + row + 1, self.x_coords + 1)); // goto row/col
-                for (col, t_character) in line.iter().enumerate() {
-                    if (col as u16) < *display_cols {
-                        // in some cases (eg. while resizing) some characters will spill over
-                        // before they are corrected by the shell (for the prompt) or by reflowing
-                        // lines
-                        vte_output.push_str(&t_character.to_string());
-                    }
-                }
-            }
-            self.should_render = false;
-            Some(vte_output)
-        } else {
-            None
-        }
-    }
-    fn read_buffer_as_lines (&self) -> Vec<Vec<&TerminalCharacter>> {
-        if DEBUGGING {
-            return vec![];
-        }
-        if self.characters.len() == 0 {
-            let mut output = vec![];
-            let mut empty_line = vec![];
-            for _ in 0..self.display_cols {
-                empty_line.push(&EMPTY_TERMINAL_CHARACTER);
-            }
-            for _ in 0..self.display_rows as usize {
-                output.push(Vec::from(empty_line.clone()));
-            }
-            return output
-        }
-        let mut output: VecDeque<Vec<&TerminalCharacter>> = VecDeque::new();
-        let mut i = self.characters.len();
-        let mut current_line: VecDeque<&TerminalCharacter> = VecDeque::new();
-        
-        let mut newline_indices = self.newline_indices.iter().rev();
-        let mut linebreak_indices = self.linebreak_indices.iter().rev();
-
-        let mut next_newline_index = newline_indices.next();
-        let mut next_linebreak_index = linebreak_indices.next();
-
-        loop {
-            i -= 1;
-            if let Some(newline_index) = next_newline_index {
-                if *newline_index == i + 1 {
-                    // pad line
-                    if current_line.len() > 0 {
-                        for _ in current_line.len()..self.display_cols as usize {
-                            current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
-                        }
-                        output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
-                    }
-                    next_newline_index = newline_indices.next();
-                }
-            }
-            if let Some(linebreak_index) = next_linebreak_index {
-                if *linebreak_index == i + 1 {
-                    // pad line
-                    if current_line.len() > 0 {
-                        for _ in current_line.len()..self.display_cols as usize {
-                            current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
-                        }
-                        output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
-                    }
-                    next_linebreak_index = linebreak_indices.next();
-                }
-            }
-            if output.len() == self.display_rows as usize {
-                if current_line.len() > 0 {
-                    for _ in current_line.len()..self.display_cols as usize {
-                        current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
-                    }
-                    output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
-                }
-                break;
-            }
-            let terminal_character = self.characters.get(i).unwrap();
-            current_line.push_front(terminal_character);
-            if i == 0 {
-                if current_line.len() > 0 {
-                    for _ in current_line.len()..self.display_cols as usize {
-                        current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
-                    }
-                    output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
-                }
-                break;
-            }
-        }
-        if output.len() < self.display_rows as usize {
-            let mut empty_line = vec![];
-            for _ in 0..self.display_cols {
-                empty_line.push(&EMPTY_TERMINAL_CHARACTER);
-            }
-            for _ in output.len()..self.display_rows as usize {
-                output.push_front(Vec::from(empty_line.clone()));
-            }
-        }
-
-        Vec::from(output)
-    }
-    pub fn cursor_position_in_last_line (&self) -> usize {
-        if self.cursor_position <= self.characters.len() {
-            let start_of_last_line = self.index_of_beginning_of_last_line();
-            if self.cursor_position < start_of_last_line {
-                // TODO: why does this happen?
-                return self.display_cols as usize
-            };
-            let difference_from_last_newline = self.cursor_position - start_of_last_line;
-            difference_from_last_newline
-        } else {
-            self.display_cols as usize
-        }
-    }
-    pub fn cursor_coordinates (&self) -> (usize, usize) { // (x, y)
-        let mut lines_from_end = 0;
-
-        let mut newline_indices = self.newline_indices.iter().rev();
-        let mut linebreak_indices = self.linebreak_indices.iter().rev();
-
-        let mut next_newline_index = newline_indices.next().unwrap_or(&0);
-        let mut next_linebreak_index = linebreak_indices.next().unwrap_or(&0);
-
-        let next_line_start = loop {
-            let next_line_start = ::std::cmp::max(*next_newline_index, *next_linebreak_index);
-            if self.cursor_position >= next_line_start {
-                break next_line_start;
-            }
-            if next_line_start == *next_newline_index {
-                next_newline_index = newline_indices.next().unwrap_or(&0);
-                lines_from_end += 1;
-            }
-            if next_line_start == *next_linebreak_index {
-                next_linebreak_index = linebreak_indices.next().unwrap_or(&0);
-                lines_from_end += 1;
-            }
-        };
-        let y = self.display_rows - lines_from_end; // TODO: this might overflow, fix when introducing scrolling
-        let x = self.cursor_position - next_line_start;
-        (x, y as usize)
-    }
-    fn index_of_beginning_of_last_line (&self) -> usize {
-        let last_newline_index = if self.newline_indices.is_empty() {
-            None
-        } else {
-            // return last
-            Some(*self.newline_indices.last().unwrap())
-        };
-        let last_linebreak_index = if self.linebreak_indices.is_empty() {
-            None
-        } else {
-            // return last
-            Some(*self.linebreak_indices.last().unwrap())
-        };
-        match (last_newline_index, last_linebreak_index) {
-            (Some(last_newline_index), Some(last_linebreak_index)) => {
-                max(last_newline_index, last_linebreak_index)
-            },
-            (None, Some(last_linebreak_index)) => last_linebreak_index,
-            (Some(last_newline_index), None) => last_newline_index,
-            (None, None) => 0
-        }
-    }
-    fn index_of_beginning_of_last_canonical_line (&self) -> usize {
-        if self.newline_indices.is_empty() {
-            0
-        } else {
-            // return last
-            *self.newline_indices.last().unwrap()
-        }
-    }
-    fn index_of_beginning_of_line (&self, index_in_line: usize) -> usize {
-        let last_newline_index = if self.newline_indices.is_empty() {
-            None
-        } else {
-            // return last less than index_in_line
-            let last_newline_index = *self.newline_indices.last().unwrap();
-            if last_newline_index <= index_in_line {
-                Some(last_newline_index)
-            } else {
-                let mut last_newline_index = 0;
-                for n_i in self.newline_indices.iter() {
-                    if *n_i > last_newline_index && *n_i <= index_in_line {
-                        last_newline_index = *n_i;
-                    } else if *n_i > index_in_line {
-                        break;
-                    }
-                }
-                Some(last_newline_index)
-            }
-        };
-        let last_linebreak_index = if self.linebreak_indices.is_empty() {
-            None
-        } else {
-            // return last less than index_in_line
-            let last_linebreak_index = *self.linebreak_indices.last().unwrap();
-            if last_linebreak_index <= index_in_line {
-                Some(last_linebreak_index)
-            } else {
-                let mut last_linebreak_index = 0;
-                for l_i in self.linebreak_indices.iter() {
-                    if *l_i > last_linebreak_index && *l_i <= index_in_line {
-                        last_linebreak_index = *l_i;
-                    } else if *l_i > index_in_line {
-                        break;
-                    }
-                }
-                Some(last_linebreak_index)
-            }
-        };
-        match (last_newline_index, last_linebreak_index) {
-            (Some(last_newline_index), Some(last_linebreak_index)) => {
-                max(last_newline_index, last_linebreak_index)
-            },
-            (None, Some(last_linebreak_index)) => last_linebreak_index,
-            (Some(last_newline_index), None) => last_newline_index,
-            (None, None) => 0
-        }
-    }
-    fn add_newline (&mut self) {
-        self.newline_indices.push(self.characters.len());
-        self.cursor_position = self.characters.len();
-        self.should_render = true;
-        self.pending_ansi_code = None;
-    }
-    fn move_to_beginning_of_line (&mut self) {
-        let last_newline_index = if self.newline_indices.is_empty() {
-            0
-        } else {
-            *self.newline_indices.last().unwrap()
-        };
-        self.cursor_position = last_newline_index;
-        self.should_render = true;
-    }
-}
-
-const DEBUGGING: bool = false;
-
-impl vte::Perform for TerminalOutput {
-    fn print(&mut self, c: char) {
-        if DEBUGGING {
-            println!("\r[print] {:?}", c);
-        } else {
-            let mut terminal_character = TerminalCharacter::new(c);
-            terminal_character.ansi_code = self.pending_ansi_code.clone();
-            if self.characters.len() == self.cursor_position {
-                self.characters.push(terminal_character);
-
-                let start_of_last_line = self.index_of_beginning_of_line(self.cursor_position);
-                let difference_from_last_newline = self.cursor_position - start_of_last_line;
-                if difference_from_last_newline == self.display_cols as usize {
-                    self.linebreak_indices.push(self.cursor_position);
-                }
-
-            } else if self.characters.len() > self.cursor_position {
-                self.characters.remove(self.cursor_position);
-                self.characters.insert(self.cursor_position, terminal_character);
-            } else {
-                let mut space_character = TerminalCharacter::new(' ');
-                space_character.ansi_code = self.pending_ansi_code.clone();
-                for _ in self.characters.len()..self.cursor_position {
-                    self.characters.push(space_character.clone());
-                };
-                self.characters.push(terminal_character);
-
-                let start_of_last_line = self.index_of_beginning_of_line(self.cursor_position);
-                let difference_from_last_newline = self.cursor_position - start_of_last_line;
-                if difference_from_last_newline == self.display_cols as usize {
-                    self.linebreak_indices.push(self.cursor_position);
-                }
-            }
-            self.cursor_position += 1;
-        }
-    }
-
-    fn execute(&mut self, byte: u8) {
-        if DEBUGGING {
-            if byte == 13 { // 0d, carriage return
-                println!("\rEXECUTE CARRIAGE RETURN");
-            } else if byte == 10 { // 0a, newline
-                println!("\rEXECUTE NEW LINE");
-            } else if byte == 08 { // backspace
-                println!("\rEXECUTE BACKSPACE");
-            } else {
-                println!("\r[execute] {:02x}", byte);
-            }
-        } else {
-            if byte == 13 { // 0d, carriage return
-                self.move_to_beginning_of_line();
-            } else if byte == 08 { // backspace
-                self.cursor_position -= 1;
-            } else if byte == 10 { // 0a, newline
-                self.add_newline();
-            }
-        }
-    }
-
-    fn hook(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
-        if DEBUGGING {
-            println!(
-                "\r[hook] params={:?}, intermediates={:?}, ignore={:?}, char={:?}",
-                params, intermediates, ignore, c
-            );
-        }
-    }
-
-    fn put(&mut self, byte: u8) {
-        if DEBUGGING {
-            println!("\r[put] {:02x}", byte);
-        }
-    }
-
-    fn unhook(&mut self) {
-        if DEBUGGING {
-            println!("\r[unhook]");
-        }
-    }
-
-    fn osc_dispatch(&mut self, params: &[&[u8]], bell_terminated: bool) {
-    // TODO: normalize vec/slices for all of these methods and the enum
-        if DEBUGGING {
-            println!("\r[osc_dispatch] params={:?} bell_terminated={}", params, bell_terminated);
-        }
-    }
-
-    fn csi_dispatch(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
-        if DEBUGGING {
-            println!(
-                "\r[csi_dispatch] params={:?}, intermediates={:?}, ignore={:?}, char={:?}",
-                params, intermediates, ignore, c
-            );
-        } else {
-            if c == 'm' {
-                // change foreground color (only?)
-                if params.len() == 1 && params[0] == 0 {
-                    // eg. \u{1b}[m
-                    self.pending_ansi_code = Some(String::from("\u{1b}[m"));
-                } else {
-                    // eg. \u{1b}[38;5;0m
-                    let param_string = params.iter().map(|p| p.to_string()).collect::<Vec<String>>().join(";");
-                    self.pending_ansi_code = Some(format!("\u{1b}[{}m", param_string));
-                }
-            } else if c == 'C' { // move cursor forward
-                self.cursor_position += params[0] as usize; // TODO: negative value?
-            } else if c == 'K' { // clear line (0 => right, 1 => left, 2 => all)
-                if params[0] == 0 {
-                    if let Some(position_of_first_newline_index_to_delete) = self.newline_indices.iter().position(|&ni| ni > self.cursor_position) {
-                        self.newline_indices.truncate(position_of_first_newline_index_to_delete);
-                    }
-                    if let Some(position_of_first_linebreak_index_to_delete) = self.linebreak_indices.iter().position(|&li| li > self.cursor_position) {
-                        self.newline_indices.truncate(position_of_first_linebreak_index_to_delete);
-                    }
-                    self.characters.truncate(self.cursor_position + 1);
-                }
-                // TODO: implement 1 and 2
-            } else if c == 'J' { // clear all (0 => below, 1 => above, 2 => all, 3 => saved)
-                if params[0] == 0 {
-                    if let Some(position_of_first_newline_index_to_delete) = self.newline_indices.iter().position(|&ni| ni > self.cursor_position) {
-                        self.newline_indices.truncate(position_of_first_newline_index_to_delete);
-                    }
-                    if let Some(position_of_first_linebreak_index_to_delete) = self.linebreak_indices.iter().position(|&li| li > self.cursor_position) {
-                        self.newline_indices.truncate(position_of_first_linebreak_index_to_delete);
-                    }
-                    self.characters.truncate(self.cursor_position + 1);
-                }
-                // TODO: implement 1, 2, and 3
-            } else if c == 'H' { // goto row/col
-                let row = params[0] as usize - 1; // we subtract 1 here because this csi is 1 indexed and we index from 0
-                let col = params[1] as usize - 1;
-
-                match self.newline_indices.get(row as usize) {
-                    Some(index_of_next_row) => {
-                        let index_of_row = index_of_next_row - self.display_cols as usize;
-                        self.cursor_position = index_of_row + col as usize;
-                    }
-                    None => {
-                        let start_of_last_line = self.index_of_beginning_of_last_canonical_line();
-                        let num_of_lines_to_add = row - self.newline_indices.len();
-                        for i in 0..num_of_lines_to_add {
-                            self.newline_indices.push(start_of_last_line + ((i + 1) * self.display_cols as usize));
-                        }
-                        let index_of_row = self.newline_indices.last().unwrap_or(&0); // TODO: better
-                        self.cursor_position = index_of_row + col as usize;
-                    }
-                }
-            }
-        }
-    }
-
-    fn esc_dispatch(&mut self, intermediates: &[u8], ignore: bool, byte: u8) {
-        if DEBUGGING {
-            println!(
-                // "\r[esc_dispatch] intermediates={:?}, ignore={:?}, byte={:02x}",
-                "\r[esc_dispatch] intermediates={:?}, ignore={:?}, byte={:?}",
-                intermediates, ignore, byte
-            );
-        }
-    }
-}
-
-#[derive(Debug)]
-pub enum VteEvent { // TODO: try not to allocate Vecs
-    Print(char),
-    Execute(u8), // byte
-    Hook(Vec<i64>, Vec<u8>, bool, char), // params, intermediates, ignore, char
-    Put(u8), // byte
-    Unhook,
-    OscDispatch(Vec<Vec<u8>>, bool), // params, bell_terminated
-    CsiDispatch(Vec<i64>, Vec<u8>, bool, char), // params, intermediates, ignore, char
-    EscDispatch(Vec<u8>, bool, u8), // intermediates, ignore, byte
-}
-
-struct VteEventSender {
-    id: RawFd,
-    sender: Sender<ScreenInstruction>,
-}
-
-impl VteEventSender {
-    pub fn new (id: RawFd, sender: Sender<ScreenInstruction>) -> Self {
-        VteEventSender { id, sender }
-    }
-}
-
-impl vte::Perform for VteEventSender {
-    fn print(&mut self, c: char) {
-        self.sender.send(
-            ScreenInstruction::Pty(self.id, VteEvent::Print(c))
-        ).unwrap();
-    }
-    fn execute(&mut self, byte: u8) {
-        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Execute(byte))).unwrap();
-    }
-
-    fn hook(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
-        let params = params.iter().copied().collect();
-        let intermediates = intermediates.iter().copied().collect();
-        let instruction = ScreenInstruction::Pty(self.id, VteEvent::Hook(params, intermediates, ignore, c));
-        self.sender.send(instruction).unwrap();
-    }
-
-    fn put(&mut self, byte: u8) {
-        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Put(byte))).unwrap();
-    }
-
-    fn unhook(&mut self) {
-        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Unhook)).unwrap();
-    }
-
-    fn osc_dispatch(&mut self, params: &[&[u8]], bell_terminated: bool) {
-        let params = params.iter().map(|p| p.to_vec()).collect();
-        let instruction = ScreenInstruction::Pty(self.id, VteEvent::OscDispatch(params, bell_terminated));
-        self.sender.send(instruction).unwrap();
-    }
-
-    fn csi_dispatch(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
-        let params = params.iter().copied().collect();
-        let intermediates = intermediates.iter().copied().collect();
-        let instruction = ScreenInstruction::Pty(self.id, VteEvent::CsiDispatch(params, intermediates, ignore, c));
-        self.sender.send(instruction).unwrap();
-    }
-
-    fn esc_dispatch(&mut self, intermediates: &[u8], ignore: bool, byte: u8) {
-        let intermediates = intermediates.iter().copied().collect();
-        let instruction = ScreenInstruction::Pty(self.id, VteEvent::EscDispatch(intermediates, ignore, byte));
-        self.sender.send(instruction).unwrap();
-    }
-}
+use crate::terminal_pane::TerminalOutput;
+use crate::pty_bus::{VteEvent, PtyBus, PtyInstruction};
+use crate::screen::{Screen, ScreenInstruction};
 
 // sigwinch stuff
 use ::signal_hook::iterator::Signals;
@@ -748,1398 +39,6 @@ pub fn sigwinch() -> (Box<OnSigWinch>, Box<SigCleanup>) {
     (Box::new(on_winch), Box::new(cleanup))
 }
 
-fn split_vertically_with_gap (rect: &Winsize) -> (Winsize, Winsize) {
-    let width_of_each_half = (rect.ws_col - 1) / 2;
-    let mut first_rect = rect.clone();
-    let mut second_rect = rect.clone();
-    if rect.ws_col % 2 == 0 {
-        first_rect.ws_col = width_of_each_half + 1;
-    } else {
-        first_rect.ws_col = width_of_each_half;
-    }
-    second_rect.ws_col = width_of_each_half;
-    (first_rect, second_rect)
-}
-
-fn split_horizontally_with_gap (rect: &Winsize) -> (Winsize, Winsize) {
-    let height_of_each_half = (rect.ws_row - 1) / 2;
-    let mut first_rect = rect.clone();
-    let mut second_rect = rect.clone();
-    if rect.ws_row % 2 == 0 {
-        first_rect.ws_row = height_of_each_half + 1;
-    } else {
-        first_rect.ws_row = height_of_each_half;
-    }
-    second_rect.ws_row = height_of_each_half;
-    (first_rect, second_rect)
-}
-
-#[derive(Debug)]
-enum ScreenInstruction {
-    Pty(RawFd, VteEvent),
-    Render,
-    HorizontalSplit(RawFd),
-    VerticalSplit(RawFd),
-    WriteCharacter(u8),
-    ResizeLeft,
-    ResizeRight,
-    ResizeDown,
-    ResizeUp,
-    MoveFocus,
-    Quit,
-}
-
-struct Screen {
-    pub receiver: Receiver<ScreenInstruction>,
-    pub send_screen_instructions: Sender<ScreenInstruction>,
-    full_screen_ws: Winsize,
-    vertical_separator: TerminalCharacter, // TODO: better
-    horizontal_separator: TerminalCharacter, // TODO: better
-    terminals: BTreeMap<RawFd, TerminalOutput>, // BTreeMap because we need a predictable order when changing focus
-    active_terminal: Option<RawFd>,
-    os_api: Box<dyn OsApi>,
-}
-
-impl Screen {
-    pub fn new (full_screen_ws: &Winsize, os_api: Box<dyn OsApi>) -> Self {
-        let (sender, receiver): (Sender<ScreenInstruction>, Receiver<ScreenInstruction>) = channel();
-        Screen {
-            receiver,
-            send_screen_instructions: sender,
-            full_screen_ws: full_screen_ws.clone(),
-            vertical_separator: TerminalCharacter::new('│').ansi_code(String::from("\u{1b}[m")), // TODO: better
-            horizontal_separator: TerminalCharacter::new('─').ansi_code(String::from("\u{1b}[m")), // TODO: better
-            terminals: BTreeMap::new(),
-            active_terminal: None,
-            os_api,
-        }
-    }
-    pub fn horizontal_split(&mut self, pid: RawFd) {
-        if self.terminals.is_empty() {
-            let x = 0;
-            let y = 0;
-            let new_terminal = TerminalOutput::new(pid, self.full_screen_ws.clone(), x, y);
-            self.os_api.set_terminal_size_using_fd(new_terminal.pid, new_terminal.display_cols, new_terminal.display_rows);
-            self.terminals.insert(pid, new_terminal);
-            self.active_terminal = Some(pid);
-        } else {
-            // TODO: check minimum size of active terminal
-            let (active_terminal_ws, active_terminal_x_coords, active_terminal_y_coords) = {
-                let active_terminal = &self.get_active_terminal().unwrap();
-                (
-                    Winsize {
-                        ws_row: active_terminal.display_rows,
-                        ws_col: active_terminal.display_cols,
-                        ws_xpixel: 0,
-                        ws_ypixel: 0,
-                    },
-                    active_terminal.x_coords,
-                    active_terminal.y_coords
-                )
-            };
-            let (top_winsize, bottom_winsize) = split_horizontally_with_gap(&active_terminal_ws);
-            let bottom_half_y = active_terminal_y_coords + top_winsize.ws_row + 1;
-            let new_terminal = TerminalOutput::new(pid, bottom_winsize, active_terminal_x_coords, bottom_half_y);
-            self.os_api.set_terminal_size_using_fd(new_terminal.pid, bottom_winsize.ws_col, bottom_winsize.ws_row);
-
-            {
-                let active_terminal_id = &self.get_active_terminal_id().unwrap();
-                let active_terminal = &mut self.terminals.get_mut(&active_terminal_id).unwrap();
-                active_terminal.change_size(&top_winsize);
-            }
-
-            self.terminals.insert(pid, new_terminal);
-            let active_terminal_pid = self.get_active_terminal_id().unwrap();
-            self.os_api.set_terminal_size_using_fd(active_terminal_pid, top_winsize.ws_col, top_winsize.ws_row);
-            self.active_terminal = Some(pid);
-            self.render();
-        }
-    }
-    pub fn vertical_split(&mut self, pid: RawFd) {
-        if self.terminals.is_empty() {
-            let x = 0;
-            let y = 0;
-            let new_terminal = TerminalOutput::new(pid, self.full_screen_ws.clone(), x, y);
-            self.os_api.set_terminal_size_using_fd(new_terminal.pid, new_terminal.display_cols, new_terminal.display_rows);
-            self.terminals.insert(pid, new_terminal);
-            self.active_terminal = Some(pid);
-        } else {
-            // TODO: check minimum size of active terminal
-            let (active_terminal_ws, active_terminal_x_coords, active_terminal_y_coords) = {
-                let active_terminal = &self.get_active_terminal().unwrap();
-                (
-                    Winsize {
-                        ws_row: active_terminal.display_rows,
-                        ws_col: active_terminal.display_cols,
-                        ws_xpixel: 0,
-                        ws_ypixel: 0,
-                    },
-                    active_terminal.x_coords,
-                    active_terminal.y_coords
-                )
-            };
-            let (left_winszie, right_winsize) = split_vertically_with_gap(&active_terminal_ws);
-            let right_side_x = active_terminal_x_coords + left_winszie.ws_col + 1;
-            let new_terminal = TerminalOutput::new(pid, right_winsize, right_side_x, active_terminal_y_coords);
-            self.os_api.set_terminal_size_using_fd(new_terminal.pid, right_winsize.ws_col, right_winsize.ws_row);
-
-            {
-                let active_terminal_id = &self.get_active_terminal_id().unwrap();
-                let active_terminal = &mut self.terminals.get_mut(&active_terminal_id).unwrap();
-                active_terminal.change_size(&left_winszie);
-            }
-
-            self.terminals.insert(pid, new_terminal);
-            let active_terminal_pid = self.get_active_terminal_id().unwrap();
-            self.os_api.set_terminal_size_using_fd(active_terminal_pid, left_winszie.ws_col, left_winszie.ws_row);
-            self.active_terminal = Some(pid);
-            self.render();
-        }
-    }
-    fn get_active_terminal (&self) -> Option<&TerminalOutput> {
-        match self.active_terminal {
-            Some(active_terminal) => self.terminals.get(&active_terminal),
-            None => None
-        }
-    }
-    fn get_active_terminal_id (&self) -> Option<RawFd> {
-        match self.active_terminal {
-            Some(active_terminal) => Some(self.terminals.get(&active_terminal).unwrap().pid),
-            None => None
-        }
-    }
-    pub fn handle_pty_event(&mut self, pid: RawFd, event: VteEvent) {
-        let terminal_output = self.terminals.get_mut(&pid).unwrap();
-        terminal_output.handle_event(event);
-    }
-    pub fn write_to_active_terminal(&mut self, byte: u8) {
-        if let Some(active_terminal_id) = &self.get_active_terminal_id() {
-            let mut buffer = [byte];
-            self.os_api.write_to_tty_stdin(*active_terminal_id, &mut buffer).expect("failed to write to terminal");
-            self.os_api.tcdrain(*active_terminal_id).expect("failed to drain terminal");
-        }
-    }
-    fn get_active_terminal_cursor_position(&self) -> (usize, usize) { // (x, y)
-        let active_terminal = &self.get_active_terminal().unwrap();
-        let x = active_terminal.x_coords as usize + active_terminal.cursor_position_in_last_line();
-        let y = active_terminal.y_coords + active_terminal.display_rows - 1;
-        (x, y as usize)
-    }
-    pub fn render (&mut self) {
-        let mut stdout = self.os_api.get_stdout_writer();
-        for (_pid, terminal) in self.terminals.iter_mut() {
-            if let Some(vte_output) = terminal.buffer_as_vte_output() {
-
-                // write boundaries
-                if terminal.x_coords + terminal.display_cols < self.full_screen_ws.ws_col {
-                    let boundary_x_coords = terminal.x_coords + terminal.display_cols;
-                    let mut vte_output_boundaries = String::new();
-                    for row in terminal.y_coords..terminal.y_coords + terminal.display_rows {
-                        vte_output_boundaries.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", row + 1, boundary_x_coords + 1)); // goto row/col
-                        vte_output_boundaries.push_str(&self.vertical_separator.to_string());
-                    }
-                    stdout.write_all(&vte_output_boundaries.as_bytes()).expect("cannot write to stdout");
-                }
-                if terminal.y_coords + terminal.display_rows < self.full_screen_ws.ws_row {
-                    let boundary_y_coords = terminal.y_coords + terminal.display_rows;
-                    let mut vte_output_boundaries = String::new();
-                    for col in terminal.x_coords..terminal.x_coords + terminal.display_cols {
-                        vte_output_boundaries.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", boundary_y_coords + 1, col + 1)); // goto row/col
-                        vte_output_boundaries.push_str(&self.horizontal_separator.to_string());
-                    }
-                    stdout.write_all(&vte_output_boundaries.as_bytes()).expect("cannot write to stdout");
-                }
-
-                stdout.write_all(&vte_output.as_bytes()).expect("cannot write to stdout");
-            }
-        }
-        let (cursor_position_x, cursor_position_y) = self.get_active_terminal_cursor_position();
-        let goto_cursor_position = format!("\u{1b}[{};{}H\u{1b}[m", cursor_position_y + 1, cursor_position_x + 1); // goto row/col
-        stdout.write_all(&goto_cursor_position.as_bytes()).expect("cannot write to stdout");
-        stdout.flush().expect("could not flush");
-    }
-    fn terminal_ids_directly_left_of(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        if terminal_to_check.x_coords == 0 {
-            return None;
-        }
-        for (pid, terminal) in self.terminals.iter() {
-            if terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords - 1 {
-                ids.push(*pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_right_of(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        for (pid, terminal) in self.terminals.iter() {
-            if terminal.x_coords == terminal_to_check.x_coords + terminal_to_check.display_cols + 1 {
-                ids.push(*pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_below(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        for (pid, terminal) in self.terminals.iter() {
-            if terminal.y_coords == terminal_to_check.y_coords + terminal_to_check.display_rows + 1 {
-                ids.push(*pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_above(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        for (pid, terminal) in self.terminals.iter() {
-            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
-                ids.push(*pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_above_with_same_left_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut left_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.x_coords == terminal_to_check.x_coords)
-            .collect();
-        left_aligned_terminals.sort_by(|a, b| { b.y_coords.cmp(&a.y_coords)});
-
-        for terminal in left_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_below_with_same_left_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut left_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.x_coords == terminal_to_check.x_coords)
-            .collect();
-        left_aligned_terminals.sort_by(|a, b| { a.y_coords.cmp(&b.y_coords)});
-
-        for terminal in left_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal_to_check.y_coords + terminal_to_check.display_rows + 1 == terminal.y_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_above_with_same_right_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut right_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords + terminal_to_check.display_cols)
-            .collect();
-        right_aligned_terminals.sort_by(|a, b| { b.y_coords.cmp(&a.y_coords)});
-
-        for terminal in right_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_below_with_same_right_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut right_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords + terminal_to_check.display_cols)
-            .collect();
-        right_aligned_terminals.sort_by(|a, b| { a.y_coords.cmp(&b.y_coords)});
-
-        for terminal in right_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal_to_check.y_coords + terminal_to_check.display_rows + 1 == terminal.y_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_to_the_left_with_same_top_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut top_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.y_coords == terminal_to_check.y_coords)
-            .collect();
-        top_aligned_terminals.sort_by(|a, b| { b.x_coords.cmp(&a.x_coords)});
-
-        for terminal in top_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal.x_coords + terminal.display_cols + 1 == terminal_to_check.x_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_to_the_left_with_same_bottom_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut bottom_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.y_coords + terminal.display_rows == terminal_to_check.y_coords + terminal_to_check.display_rows)
-            .collect();
-        bottom_aligned_terminals.sort_by(|a, b| { b.x_coords.cmp(&a.x_coords)});
-
-        for terminal in bottom_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal.x_coords + terminal.display_cols + 1 == terminal_to_check.x_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_to_the_right_with_same_top_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut top_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.y_coords == terminal_to_check.y_coords)
-            .collect();
-        top_aligned_terminals.sort_by(|a, b| { a.x_coords.cmp(&b.x_coords)});
-
-        for terminal in top_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal_to_check.x_coords + terminal_to_check.display_cols + 1 == terminal.x_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    fn terminal_ids_directly_to_the_right_with_same_bottom_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
-        let mut ids = vec![];
-        let terminal_to_check = self.terminals.get(id).unwrap();
-        let mut bottom_aligned_terminals: Vec<&TerminalOutput> = self.terminals
-            .keys()
-            .map(|t_id| self.terminals.get(&t_id).unwrap())
-            .filter(|terminal| terminal.pid != *id && terminal.y_coords + terminal.display_rows == terminal_to_check.y_coords + terminal_to_check.display_rows)
-            .collect();
-        bottom_aligned_terminals.sort_by(|a, b| { a.x_coords.cmp(&b.x_coords)});
-
-        for terminal in bottom_aligned_terminals {
-            let terminal_to_check = ids
-                .last()
-                .and_then(|id| self.terminals.get(id))
-                .unwrap_or(terminal_to_check);
-            if terminal_to_check.x_coords + terminal_to_check.display_cols + 1 == terminal.x_coords {
-                ids.push(terminal.pid);
-            }
-        }
-        if ids.is_empty() {
-            None
-        } else {
-            Some(ids)
-        }
-    }
-    pub fn resize_left (&mut self) {
-        // TODO: find out by how much we actually reduced and only reduce by that much
-        let count = 10;
-        if let Some(active_terminal_id) = self.get_active_terminal_id() {
-            let terminals_to_the_left = self.terminal_ids_directly_left_of(&active_terminal_id);
-            let terminals_to_the_right = self.terminal_ids_directly_right_of(&active_terminal_id);
-            match (terminals_to_the_left, terminals_to_the_right) {
-                (_, Some(mut terminals_to_the_right)) => {
-                    // reduce to the left
-                    let terminal_borders_to_the_right: HashSet<u16> = terminals_to_the_right.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
-                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_right_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut upper_resize_border = 0;
-                            for terminal in &t {
-                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
-                                if terminal_borders_to_the_right.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
-                                    upper_resize_border = lower_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords >= upper_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, upper_resize_border))
-                        });
-                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_right_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut lower_resize_border = self.full_screen_ws.ws_row;
-                            for terminal in &t {
-                                let upper_terminal_boundary = terminal.y_coords;
-                                if terminal_borders_to_the_right.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
-                                    lower_resize_border = upper_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords + terminal.display_rows <= lower_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, lower_resize_border))
-                        });
-                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
-                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
-                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
-                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
-
-                    active_terminal.reduce_width_left(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_to_the_right.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
-                    });
-                    for terminal_id in terminals_to_the_right {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.increase_width_left(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_above) = terminals_above {
-                        for terminal_id in terminals_above.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_width_left(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_below) = terminals_below {
-                        for terminal_id in terminals_below.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_width_left(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (Some(mut terminals_to_the_left), None) => {
-                    // increase to the left 
-                    let terminal_borders_to_the_left: HashSet<u16> = terminals_to_the_left.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
-                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_left_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut upper_resize_border = 0;
-                            for terminal in &t {
-                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
-                                if terminal_borders_to_the_left.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
-                                    upper_resize_border = lower_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords >= upper_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, upper_resize_border))
-                        });
-                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_left_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut lower_resize_border = self.full_screen_ws.ws_row;
-                            for terminal in &t {
-                                let upper_terminal_boundary = terminal.y_coords;
-                                if terminal_borders_to_the_left.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
-                                    lower_resize_border = upper_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords + terminal.display_rows <= lower_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, lower_resize_border))
-                        });
-                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
-                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
-                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
-                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
-
-                    active_terminal.increase_width_left(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_to_the_left.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
-                    });
-                    for terminal_id in terminals_to_the_left {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.reduce_width_left(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_above) = terminals_above {
-                        for terminal_id in terminals_above.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_width_left(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_below) = terminals_below {
-                        for terminal_id in terminals_below.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_width_left(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (None, None) => {}
-            }
-            self.render();
-        }
-    }
-    pub fn resize_right (&mut self) {
-        let count = 10;
-        if let Some(active_terminal_id) = self.get_active_terminal_id() {
-            let terminals_to_the_left = self.terminal_ids_directly_left_of(&active_terminal_id);
-            let terminals_to_the_right = self.terminal_ids_directly_right_of(&active_terminal_id);
-            match (terminals_to_the_left, terminals_to_the_right) {
-                (_, Some(mut terminals_to_the_right)) => {
-                    // increase to the right
-                    let terminal_borders_to_the_right: HashSet<u16> = terminals_to_the_right.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
-                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_right_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut upper_resize_border = 0;
-                            for terminal in &t {
-                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
-                                if terminal_borders_to_the_right.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
-                                    upper_resize_border = lower_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords >= upper_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, upper_resize_border))
-                        });
-                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_right_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut lower_resize_border = self.full_screen_ws.ws_row;
-                            for terminal in &t {
-                                let upper_terminal_boundary = terminal.y_coords;
-                                if terminal_borders_to_the_right.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
-                                    lower_resize_border = upper_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords + terminal.display_rows <= lower_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, lower_resize_border))
-                        });
-                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
-                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
-                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
-                        None => (None, None),
-                    };
-
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
-                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
-
-                    active_terminal.increase_width_right(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_to_the_right.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
-                    });
-                    for terminal_id in terminals_to_the_right {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.reduce_width_right(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_above) = terminals_above {
-                        for terminal_id in terminals_above.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_width_right(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_below) = terminals_below {
-                        for terminal_id in terminals_below.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_width_right(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (Some(mut terminals_to_the_left), None) => {
-                    // reduce to the right
-                    let terminal_borders_to_the_left: HashSet<u16> = terminals_to_the_left.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
-                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_left_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut upper_resize_border = 0;
-                            for terminal in &t {
-                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
-                                if terminal_borders_to_the_left.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
-                                    upper_resize_border = lower_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords >= upper_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, upper_resize_border))
-                        });
-                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_left_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut lower_resize_border = self.full_screen_ws.ws_row;
-                            for terminal in &t {
-                                let upper_terminal_boundary = terminal.y_coords;
-                                if terminal_borders_to_the_left.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
-                                    lower_resize_border = upper_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.y_coords + terminal.display_rows <= lower_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, lower_resize_border))
-                        });
-                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
-                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
-                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
-                        None => (None, None),
-                    };
-
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
-                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
-
-                    active_terminal.reduce_width_right(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_to_the_left.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
-                    });
-                    for terminal_id in terminals_to_the_left {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.increase_width_right(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_above) = terminals_above {
-                        for terminal_id in terminals_above.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_width_right(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_below) = terminals_below {
-                        for terminal_id in terminals_below.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_width_right(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (None, None) => {}
-            }
-            self.render();
-        }
-    }
-    pub fn resize_down (&mut self) {
-        // TODO: find out by how much we actually reduced and only reduce by that much
-        let count = 2;
-        if let Some(active_terminal_id) = self.get_active_terminal_id() {
-            let terminals_below = self.terminal_ids_directly_below(&active_terminal_id);
-            let terminals_above = self.terminal_ids_directly_above(&active_terminal_id);
-            match (terminals_below, terminals_above) {
-                (_, Some(mut terminals_above)) => {
-                    // reduce down
-                    let terminal_borders_above: HashSet<u16> = terminals_above.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
-                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_top_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut left_resize_border = 0;
-                            for terminal in &t {
-                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
-                                if terminal_borders_above.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
-                                    left_resize_border = right_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords >= left_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, left_resize_border))
-                        });
-                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_top_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut right_resize_border = self.full_screen_ws.ws_col;
-                            for terminal in &t {
-                                let left_terminal_boundary = terminal.x_coords;
-                                if terminal_borders_above.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
-                                    right_resize_border = left_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords + terminal.display_cols <= right_resize_border 
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, right_resize_border))
-                        });
-                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
-                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
-                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
-                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
-
-                    active_terminal.reduce_height_down(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_above.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border
-                    });
-                    for terminal_id in terminals_above {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.increase_height_down(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_to_the_left) = terminals_to_the_left {
-                        for terminal_id in terminals_to_the_left.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_height_down(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_to_the_right) = terminals_to_the_right {
-                        for terminal_id in terminals_to_the_right.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_height_down(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (Some(mut terminals_below), None) => {
-                    // increase down
-                    let terminal_borders_below: HashSet<u16> = terminals_below.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
-                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_bottom_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut left_resize_border = 0;
-                            for terminal in &t {
-                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
-                                if terminal_borders_below.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
-                                    left_resize_border = right_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords >= left_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, left_resize_border))
-                        });
-                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_bottom_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut right_resize_border = self.full_screen_ws.ws_col;
-                            for terminal in &t {
-                                let left_terminal_boundary = terminal.x_coords;
-                                if terminal_borders_below.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
-                                    right_resize_border = left_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords + terminal.display_cols <= right_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, right_resize_border))
-                        });
-                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
-                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
-                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
-                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
-
-                    active_terminal.increase_height_down(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_below.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border 
-                    });
-                    for terminal_id in terminals_below {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.reduce_height_down(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_to_the_left) = terminals_to_the_left {
-                        for terminal_id in terminals_to_the_left.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_height_down(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_to_the_right) = terminals_to_the_right {
-                        for terminal_id in terminals_to_the_right.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_height_down(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (None, None) => {}
-            }
-            self.render();
-        }
-    }
-    pub fn resize_up (&mut self) {
-        // TODO: find out by how much we actually reduced and only reduce by that much
-        let count = 2;
-        if let Some(active_terminal_id) = self.get_active_terminal_id() {
-            let terminals_below = self.terminal_ids_directly_below(&active_terminal_id);
-            let terminals_above = self.terminal_ids_directly_above(&active_terminal_id);
-            match (terminals_below, terminals_above) {
-                (_, Some(mut terminals_above)) => {
-                    // reduce down
-                    let terminal_borders_above: HashSet<u16> = terminals_above.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
-                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_top_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut left_resize_border = 0;
-                            for terminal in &t {
-                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
-                                if terminal_borders_above.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
-                                    left_resize_border = right_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords >= left_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, left_resize_border))
-                        });
-                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_top_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut right_resize_border = self.full_screen_ws.ws_col;
-                            for terminal in &t {
-                                let left_terminal_boundary = terminal.x_coords;
-                                if terminal_borders_above.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
-                                    right_resize_border = left_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords + terminal.display_cols <= right_resize_border 
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, right_resize_border))
-                        });
-                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
-                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
-                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
-                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
-
-                    active_terminal.increase_height_up(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_above.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border
-                    });
-                    for terminal_id in terminals_above {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.reduce_height_up(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_to_the_left) = terminals_to_the_left {
-                        for terminal_id in terminals_to_the_left.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_height_up(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_to_the_right) = terminals_to_the_right {
-                        for terminal_id in terminals_to_the_right.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.increase_height_up(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (Some(mut terminals_below), None) => {
-                    // increase down
-                    let terminal_borders_below: HashSet<u16> = terminals_below.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
-                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_bottom_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut left_resize_border = 0;
-                            for terminal in &t {
-                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
-                                if terminal_borders_below.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
-                                    left_resize_border = right_terminal_boundary + 1;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords >= left_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, left_resize_border))
-                        });
-                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_bottom_alignment(&active_terminal_id)
-                        .and_then(|t| {
-                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
-                            Some(terminals)
-                        })
-                        .and_then(|mut t| {
-                            let mut right_resize_border = self.full_screen_ws.ws_col;
-                            for terminal in &t {
-                                let left_terminal_boundary = terminal.x_coords;
-                                if terminal_borders_below.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
-                                    right_resize_border = left_terminal_boundary;
-                                }
-                            }
-                            t.retain(|terminal| {
-                                terminal.x_coords + terminal.display_cols <= right_resize_border
-                            });
-                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
-                            Some((terminal_ids, right_resize_border))
-                        });
-                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
-                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
-                        None => (None, None),
-                    };
-                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
-                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
-                        None => (None, None),
-                    };
-                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
-                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
-                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols); // TODO: + 1?
-
-                    active_terminal.reduce_height_up(count);
-                    self.os_api.set_terminal_size_using_fd(
-                        active_terminal.pid,
-                        active_terminal.display_cols,
-                        active_terminal.display_rows
-                    );
-
-                    terminals_below.retain(|t| {
-                        let terminal = self.terminals.get(t).unwrap();
-                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border 
-                    });
-                    for terminal_id in terminals_below {
-                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
-                        terminal.increase_height_up(count);
-                        self.os_api.set_terminal_size_using_fd(
-                            terminal.pid,
-                            terminal.display_cols,
-                            terminal.display_rows
-                        );
-                    }
-
-                    if let Some(terminals_to_the_left) = terminals_to_the_left {
-                        for terminal_id in terminals_to_the_left.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_height_up(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-
-                    if let Some(terminals_to_the_right) = terminals_to_the_right {
-                        for terminal_id in terminals_to_the_right.iter() {
-                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
-                            terminal.reduce_height_up(count);
-                            self.os_api.set_terminal_size_using_fd(
-                                terminal.pid,
-                                terminal.display_cols,
-                                terminal.display_rows
-                            );
-                        }
-                    }
-                },
-                (None, None) => {}
-            }
-            self.render();
-        }
-    }
-    pub fn move_focus(&mut self) {
-        if self.terminals.is_empty() {
-            return;
-        }
-        let active_terminal_id = self.get_active_terminal_id().unwrap();
-        let terminal_ids: Vec<RawFd> = self.terminals.keys().copied().collect(); // TODO: better, no allocations
-        let first_terminal = terminal_ids.get(0).unwrap();
-        let active_terminal_id_position = terminal_ids.iter().position(|id| id == &active_terminal_id).unwrap();
-        if let Some(next_terminal) = terminal_ids.get(active_terminal_id_position + 1) {
-            self.active_terminal = Some(*next_terminal);
-        } else {
-            self.active_terminal = Some(*first_terminal);
-        }
-        self.render();
-    }
-}
-
-enum PtyInstruction {
-    SpawnTerminalVertically,
-    SpawnTerminalHorizontally,
-    Quit
-}
-
-struct PtyBus {
-    receive_pty_instructions: Receiver<PtyInstruction>,
-    send_pty_instructions: Sender<PtyInstruction>,
-    send_screen_instructions: Sender<ScreenInstruction>,
-    os_input: Box<dyn OsApi>,
-}
-
-impl PtyBus {
-    pub fn new (send_screen_instructions: Sender<ScreenInstruction>, os_input: Box<dyn OsApi>) -> Self {
-        let (send_pty_instructions, receive_pty_instructions): (Sender<PtyInstruction>, Receiver<PtyInstruction>) = channel();
-        PtyBus {
-            send_pty_instructions,
-            send_screen_instructions,
-            receive_pty_instructions,
-            os_input,
-        }
-    }
-    pub fn spawn_terminal_vertically(&mut self) {
-        let (pid_primary, _pid_secondary): (RawFd, RawFd) = self.os_input.spawn_terminal();
-        task::spawn({
-            let send_screen_instructions = self.send_screen_instructions.clone();
-            let os_input = self.os_input.clone();
-            async move {
-                let mut vte_parser = vte::Parser::new();
-                let mut vte_event_sender = VteEventSender::new(pid_primary, send_screen_instructions.clone());
-                let mut first_terminal_bytes = ReadFromPid::new(&pid_primary, os_input);
-                while let Some(bytes) = first_terminal_bytes.next().await {
-                    let bytes_is_empty = bytes.is_empty();
-                    for byte in bytes {
-                        vte_parser.advance(&mut vte_event_sender, byte);
-                    }
-                    if !bytes_is_empty {
-                        send_screen_instructions.send(ScreenInstruction::Render).unwrap();
-                    } else {
-                        task::sleep(::std::time::Duration::from_millis(10)).await;
-                    }
-                }
-            }
-        });
-        self.send_screen_instructions.send(ScreenInstruction::VerticalSplit(pid_primary)).unwrap();
-    }
-    pub fn spawn_terminal_horizontally(&mut self) {
-        let (pid_primary, _pid_secondary): (RawFd, RawFd) = self.os_input.spawn_terminal();
-        task::spawn({
-            let send_screen_instructions = self.send_screen_instructions.clone();
-            let os_input = self.os_input.clone();
-            async move {
-                let mut vte_parser = vte::Parser::new();
-                let mut vte_event_sender = VteEventSender::new(pid_primary, send_screen_instructions.clone());
-                let mut first_terminal_bytes = ReadFromPid::new(&pid_primary, os_input);
-                while let Some(bytes) = first_terminal_bytes.next().await {
-                    let bytes_is_empty = bytes.is_empty();
-                    for byte in bytes {
-                        vte_parser.advance(&mut vte_event_sender, byte);
-                    }
-                    if !bytes_is_empty {
-                        send_screen_instructions.send(ScreenInstruction::Render).unwrap();
-                    } else {
-                        task::sleep(::std::time::Duration::from_millis(10)).await;
-                    }
-                }
-            }
-        });
-        self.send_screen_instructions.send(ScreenInstruction::HorizontalSplit(pid_primary)).unwrap();
-    }
-}
-
 pub fn main() {
     let os_input = get_os_input();
     start(Box::new(os_input));
@@ -2267,5 +166,4 @@ pub fn start(mut os_input: Box<dyn OsApi>) {
 
     os_input.get_stdout_writer().write(goodbye_message.as_bytes()).unwrap();
     os_input.get_stdout_writer().flush().unwrap();
-
 }
diff --git a/src/pty_bus.rs b/src/pty_bus.rs
new file mode 100644
index 00000000..cc166120
--- /dev/null
+++ b/src/pty_bus.rs
@@ -0,0 +1,197 @@
+use ::std::os::unix::io::RawFd;
+use ::async_std::stream::*;
+use ::async_std::task;
+use ::async_std::task::*;
+use ::std::pin::*;
+use ::std::sync::mpsc::{channel, Sender, Receiver};
+use ::vte;
+
+use crate::os_input_output::OsApi;
+use crate::ScreenInstruction;
+
+pub struct ReadFromPid {
+    pid: RawFd,
+    os_input: Box<dyn OsApi>,
+}
+
+impl ReadFromPid {
+    pub fn new(pid: &RawFd, os_input: Box<dyn OsApi>) -> ReadFromPid {
+        ReadFromPid {
+            pid: *pid,
+            os_input,
+        }
+    }
+}
+
+impl Stream for ReadFromPid {
+    type Item = Vec<u8>;
+    fn poll_next(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        let mut read_buffer = [0; 115200];
+        let pid = self.pid;
+        let read_result = &self.os_input.read_from_tty_stdout(pid, &mut read_buffer);
+        match read_result {
+            Ok(res) => {
+                if *res == 0 {
+                    // indicates end of file
+                    return Poll::Ready(None);
+                } else {
+                    let res = Some(read_buffer[..=*res].to_vec());
+                    return Poll::Ready(res);
+                }
+            },
+            Err(e) => {
+                match e {
+                    nix::Error::Sys(errno) => {
+                        if *errno == nix::errno::Errno::EAGAIN {
+                            return Poll::Ready(Some(vec![])) // TODO: better with timeout waker somehow
+                        } else {
+                            Poll::Ready(None)
+                        }
+                    },
+                    _ => Poll::Ready(None)
+                }
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+pub enum VteEvent { // TODO: try not to allocate Vecs
+    Print(char),
+    Execute(u8), // byte
+    Hook(Vec<i64>, Vec<u8>, bool, char), // params, intermediates, ignore, char
+    Put(u8), // byte
+    Unhook,
+    OscDispatch(Vec<Vec<u8>>, bool), // params, bell_terminated
+    CsiDispatch(Vec<i64>, Vec<u8>, bool, char), // params, intermediates, ignore, char
+    EscDispatch(Vec<u8>, bool, u8), // intermediates, ignore, byte
+}
+
+struct VteEventSender {
+    id: RawFd,
+    sender: Sender<ScreenInstruction>,
+}
+
+impl VteEventSender {
+    pub fn new (id: RawFd, sender: Sender<ScreenInstruction>) -> Self {
+        VteEventSender { id, sender }
+    }
+}
+
+impl vte::Perform for VteEventSender {
+    fn print(&mut self, c: char) {
+        self.sender.send(
+            ScreenInstruction::Pty(self.id, VteEvent::Print(c))
+        ).unwrap();
+    }
+    fn execute(&mut self, byte: u8) {
+        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Execute(byte))).unwrap();
+    }
+
+    fn hook(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
+        let params = params.iter().copied().collect();
+        let intermediates = intermediates.iter().copied().collect();
+        let instruction = ScreenInstruction::Pty(self.id, VteEvent::Hook(params, intermediates, ignore, c));
+        self.sender.send(instruction).unwrap();
+    }
+
+    fn put(&mut self, byte: u8) {
+        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Put(byte))).unwrap();
+    }
+
+    fn unhook(&mut self) {
+        self.sender.send(ScreenInstruction::Pty(self.id, VteEvent::Unhook)).unwrap();
+    }
+
+    fn osc_dispatch(&mut self, params: &[&[u8]], bell_terminated: bool) {
+        let params = params.iter().map(|p| p.to_vec()).collect();
+        let instruction = ScreenInstruction::Pty(self.id, VteEvent::OscDispatch(params, bell_terminated));
+        self.sender.send(instruction).unwrap();
+    }
+
+    fn csi_dispatch(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
+        let params = params.iter().copied().collect();
+        let intermediates = intermediates.iter().copied().collect();
+        let instruction = ScreenInstruction::Pty(self.id, VteEvent::CsiDispatch(params, intermediates, ignore, c));
+        self.sender.send(instruction).unwrap();
+    }
+
+    fn esc_dispatch(&mut self, intermediates: &[u8], ignore: bool, byte: u8) {
+        let intermediates = intermediates.iter().copied().collect();
+        let instruction = ScreenInstruction::Pty(self.id, VteEvent::EscDispatch(intermediates, ignore, byte));
+        self.sender.send(instruction).unwrap();
+    }
+}
+
+pub enum PtyInstruction {
+    SpawnTerminalVertically,
+    SpawnTerminalHorizontally,
+    Quit
+}
+
+pub struct PtyBus {
+    pub send_pty_instructions: Sender<PtyInstruction>,
+    pub send_screen_instructions: Sender<ScreenInstruction>,
+    pub receive_pty_instructions: Receiver<PtyInstruction>,
+    os_input: Box<dyn OsApi>,
+}
+
+impl PtyBus {
+    pub fn new (send_screen_instructions: Sender<ScreenInstruction>, os_input: Box<dyn OsApi>) -> Self {
+        let (send_pty_instructions, receive_pty_instructions): (Sender<PtyInstruction>, Receiver<PtyInstruction>) = channel();
+        PtyBus {
+            send_pty_instructions,
+            send_screen_instructions,
+            receive_pty_instructions,
+            os_input,
+        }
+    }
+    pub fn spawn_terminal_vertically(&mut self) {
+        let (pid_primary, _pid_secondary): (RawFd, RawFd) = self.os_input.spawn_terminal();
+        task::spawn({
+            let send_screen_instructions = self.send_screen_instructions.clone();
+            let os_input = self.os_input.clone();
+            async move {
+                let mut vte_parser = vte::Parser::new();
+                let mut vte_event_sender = VteEventSender::new(pid_primary, send_screen_instructions.clone());
+                let mut first_terminal_bytes = ReadFromPid::new(&pid_primary, os_input);
+                while let Some(bytes) = first_terminal_bytes.next().await {
+                    let bytes_is_empty = bytes.is_empty();
+                    for byte in bytes {
+                        vte_parser.advance(&mut vte_event_sender, byte);
+                    }
+                    if !bytes_is_empty {
+                        send_screen_instructions.send(ScreenInstruction::Render).unwrap();
+                    } else {
+                        task::sleep(::std::time::Duration::from_millis(10)).await;
+                    }
+                }
+            }
+        });
+        self.send_screen_instructions.send(ScreenInstruction::VerticalSplit(pid_primary)).unwrap();
+    }
+    pub fn spawn_terminal_horizontally(&mut self) {
+        let (pid_primary, _pid_secondary): (RawFd, RawFd) = self.os_input.spawn_terminal();
+        task::spawn({
+            let send_screen_instructions = self.send_screen_instructions.clone();
+            let os_input = self.os_input.clone();
+            async move {
+                let mut vte_parser = vte::Parser::new();
+                let mut vte_event_sender = VteEventSender::new(pid_primary, send_screen_instructions.clone());
+                let mut first_terminal_bytes = ReadFromPid::new(&pid_primary, os_input);
+                while let Some(bytes) = first_terminal_bytes.next().await {
+                    let bytes_is_empty = bytes.is_empty();
+                    for byte in bytes {
+                        vte_parser.advance(&mut vte_event_sender, byte);
+                    }
+                    if !bytes_is_empty {
+                        send_screen_instructions.send(ScreenInstruction::Render).unwrap();
+                    } else {
+                        task::sleep(::std::time::Duration::from_millis(10)).await;
+                    }
+                }
+            }
+        });
+        self.send_screen_instructions.send(ScreenInstruction::HorizontalSplit(pid_primary)).unwrap();
+    }
+}
diff --git a/src/screen.rs b/src/screen.rs
new file mode 100644
index 00000000..106b68d8
--- /dev/null
+++ b/src/screen.rs
@@ -0,0 +1,1328 @@
+use std::io::Write;
+use std::collections::{HashSet, BTreeMap};
+use nix::pty::Winsize;
+use std::os::unix::io::RawFd;
+use std::sync::mpsc::{channel, Sender, Receiver};
+
+use crate::os_input_output::OsApi;
+use crate::terminal_pane::{TerminalOutput, TerminalCharacter};
+use crate::pty_bus::VteEvent;
+
+fn split_vertically_with_gap (rect: &Winsize) -> (Winsize, Winsize) {
+    let width_of_each_half = (rect.ws_col - 1) / 2;
+    let mut first_rect = rect.clone();
+    let mut second_rect = rect.clone();
+    if rect.ws_col % 2 == 0 {
+        first_rect.ws_col = width_of_each_half + 1;
+    } else {
+        first_rect.ws_col = width_of_each_half;
+    }
+    second_rect.ws_col = width_of_each_half;
+    (first_rect, second_rect)
+}
+
+fn split_horizontally_with_gap (rect: &Winsize) -> (Winsize, Winsize) {
+    let height_of_each_half = (rect.ws_row - 1) / 2;
+    let mut first_rect = rect.clone();
+    let mut second_rect = rect.clone();
+    if rect.ws_row % 2 == 0 {
+        first_rect.ws_row = height_of_each_half + 1;
+    } else {
+        first_rect.ws_row = height_of_each_half;
+    }
+    second_rect.ws_row = height_of_each_half;
+    (first_rect, second_rect)
+}
+
+#[derive(Debug)]
+pub enum ScreenInstruction {
+    Pty(RawFd, VteEvent),
+    Render,
+    HorizontalSplit(RawFd),
+    VerticalSplit(RawFd),
+    WriteCharacter(u8),
+    ResizeLeft,
+    ResizeRight,
+    ResizeDown,
+    ResizeUp,
+    MoveFocus,
+    Quit,
+}
+
+pub struct Screen {
+    pub receiver: Receiver<ScreenInstruction>,
+    pub send_screen_instructions: Sender<ScreenInstruction>,
+    full_screen_ws: Winsize,
+    vertical_separator: TerminalCharacter, // TODO: better
+    horizontal_separator: TerminalCharacter, // TODO: better
+    terminals: BTreeMap<RawFd, TerminalOutput>, // BTreeMap because we need a predictable order when changing focus
+    active_terminal: Option<RawFd>,
+    os_api: Box<dyn OsApi>,
+}
+
+impl Screen {
+    pub fn new (full_screen_ws: &Winsize, os_api: Box<dyn OsApi>) -> Self {
+        let (sender, receiver): (Sender<ScreenInstruction>, Receiver<ScreenInstruction>) = channel();
+        Screen {
+            receiver,
+            send_screen_instructions: sender,
+            full_screen_ws: full_screen_ws.clone(),
+            vertical_separator: TerminalCharacter::new('│').ansi_code(String::from("\u{1b}[m")), // TODO: better
+            horizontal_separator: TerminalCharacter::new('─').ansi_code(String::from("\u{1b}[m")), // TODO: better
+            terminals: BTreeMap::new(),
+            active_terminal: None,
+            os_api,
+        }
+    }
+    pub fn horizontal_split(&mut self, pid: RawFd) {
+        if self.terminals.is_empty() {
+            let x = 0;
+            let y = 0;
+            let new_terminal = TerminalOutput::new(pid, self.full_screen_ws.clone(), x, y);
+            self.os_api.set_terminal_size_using_fd(new_terminal.pid, new_terminal.display_cols, new_terminal.display_rows);
+            self.terminals.insert(pid, new_terminal);
+            self.active_terminal = Some(pid);
+        } else {
+            // TODO: check minimum size of active terminal
+            let (active_terminal_ws, active_terminal_x_coords, active_terminal_y_coords) = {
+                let active_terminal = &self.get_active_terminal().unwrap();
+                (
+                    Winsize {
+                        ws_row: active_terminal.display_rows,
+                        ws_col: active_terminal.display_cols,
+                        ws_xpixel: 0,
+                        ws_ypixel: 0,
+                    },
+                    active_terminal.x_coords,
+                    active_terminal.y_coords
+                )
+            };
+            let (top_winsize, bottom_winsize) = split_horizontally_with_gap(&active_terminal_ws);
+            let bottom_half_y = active_terminal_y_coords + top_winsize.ws_row + 1;
+            let new_terminal = TerminalOutput::new(pid, bottom_winsize, active_terminal_x_coords, bottom_half_y);
+            self.os_api.set_terminal_size_using_fd(new_terminal.pid, bottom_winsize.ws_col, bottom_winsize.ws_row);
+
+            {
+                let active_terminal_id = &self.get_active_terminal_id().unwrap();
+                let active_terminal = &mut self.terminals.get_mut(&active_terminal_id).unwrap();
+                active_terminal.change_size(&top_winsize);
+            }
+
+            self.terminals.insert(pid, new_terminal);
+            let active_terminal_pid = self.get_active_terminal_id().unwrap();
+            self.os_api.set_terminal_size_using_fd(active_terminal_pid, top_winsize.ws_col, top_winsize.ws_row);
+            self.active_terminal = Some(pid);
+            self.render();
+        }
+    }
+    pub fn vertical_split(&mut self, pid: RawFd) {
+        if self.terminals.is_empty() {
+            let x = 0;
+            let y = 0;
+            let new_terminal = TerminalOutput::new(pid, self.full_screen_ws.clone(), x, y);
+            self.os_api.set_terminal_size_using_fd(new_terminal.pid, new_terminal.display_cols, new_terminal.display_rows);
+            self.terminals.insert(pid, new_terminal);
+            self.active_terminal = Some(pid);
+        } else {
+            // TODO: check minimum size of active terminal
+            let (active_terminal_ws, active_terminal_x_coords, active_terminal_y_coords) = {
+                let active_terminal = &self.get_active_terminal().unwrap();
+                (
+                    Winsize {
+                        ws_row: active_terminal.display_rows,
+                        ws_col: active_terminal.display_cols,
+                        ws_xpixel: 0,
+                        ws_ypixel: 0,
+                    },
+                    active_terminal.x_coords,
+                    active_terminal.y_coords
+                )
+            };
+            let (left_winszie, right_winsize) = split_vertically_with_gap(&active_terminal_ws);
+            let right_side_x = active_terminal_x_coords + left_winszie.ws_col + 1;
+            let new_terminal = TerminalOutput::new(pid, right_winsize, right_side_x, active_terminal_y_coords);
+            self.os_api.set_terminal_size_using_fd(new_terminal.pid, right_winsize.ws_col, right_winsize.ws_row);
+
+            {
+                let active_terminal_id = &self.get_active_terminal_id().unwrap();
+                let active_terminal = &mut self.terminals.get_mut(&active_terminal_id).unwrap();
+                active_terminal.change_size(&left_winszie);
+            }
+
+            self.terminals.insert(pid, new_terminal);
+            let active_terminal_pid = self.get_active_terminal_id().unwrap();
+            self.os_api.set_terminal_size_using_fd(active_terminal_pid, left_winszie.ws_col, left_winszie.ws_row);
+            self.active_terminal = Some(pid);
+            self.render();
+        }
+    }
+    fn get_active_terminal (&self) -> Option<&TerminalOutput> {
+        match self.active_terminal {
+            Some(active_terminal) => self.terminals.get(&active_terminal),
+            None => None
+        }
+    }
+    fn get_active_terminal_id (&self) -> Option<RawFd> {
+        match self.active_terminal {
+            Some(active_terminal) => Some(self.terminals.get(&active_terminal).unwrap().pid),
+            None => None
+        }
+    }
+    pub fn handle_pty_event(&mut self, pid: RawFd, event: VteEvent) {
+        let terminal_output = self.terminals.get_mut(&pid).unwrap();
+        terminal_output.handle_event(event);
+    }
+    pub fn write_to_active_terminal(&mut self, byte: u8) {
+        if let Some(active_terminal_id) = &self.get_active_terminal_id() {
+            let mut buffer = [byte];
+            self.os_api.write_to_tty_stdin(*active_terminal_id, &mut buffer).expect("failed to write to terminal");
+            self.os_api.tcdrain(*active_terminal_id).expect("failed to drain terminal");
+        }
+    }
+    fn get_active_terminal_cursor_position(&self) -> (usize, usize) { // (x, y)
+        let active_terminal = &self.get_active_terminal().unwrap();
+        let x = active_terminal.x_coords as usize + active_terminal.cursor_position_in_last_line();
+        let y = active_terminal.y_coords + active_terminal.display_rows - 1;
+        (x, y as usize)
+    }
+    pub fn render (&mut self) {
+        let mut stdout = self.os_api.get_stdout_writer();
+        for (_pid, terminal) in self.terminals.iter_mut() {
+            if let Some(vte_output) = terminal.buffer_as_vte_output() {
+
+                // write boundaries
+                if terminal.x_coords + terminal.display_cols < self.full_screen_ws.ws_col {
+                    let boundary_x_coords = terminal.x_coords + terminal.display_cols;
+                    let mut vte_output_boundaries = String::new();
+                    for row in terminal.y_coords..terminal.y_coords + terminal.display_rows {
+                        vte_output_boundaries.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", row + 1, boundary_x_coords + 1)); // goto row/col
+                        vte_output_boundaries.push_str(&self.vertical_separator.to_string());
+                    }
+                    stdout.write_all(&vte_output_boundaries.as_bytes()).expect("cannot write to stdout");
+                }
+                if terminal.y_coords + terminal.display_rows < self.full_screen_ws.ws_row {
+                    let boundary_y_coords = terminal.y_coords + terminal.display_rows;
+                    let mut vte_output_boundaries = String::new();
+                    for col in terminal.x_coords..terminal.x_coords + terminal.display_cols {
+                        vte_output_boundaries.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", boundary_y_coords + 1, col + 1)); // goto row/col
+                        vte_output_boundaries.push_str(&self.horizontal_separator.to_string());
+                    }
+                    stdout.write_all(&vte_output_boundaries.as_bytes()).expect("cannot write to stdout");
+                }
+
+                stdout.write_all(&vte_output.as_bytes()).expect("cannot write to stdout");
+            }
+        }
+        let (cursor_position_x, cursor_position_y) = self.get_active_terminal_cursor_position();
+        let goto_cursor_position = format!("\u{1b}[{};{}H\u{1b}[m", cursor_position_y + 1, cursor_position_x + 1); // goto row/col
+        stdout.write_all(&goto_cursor_position.as_bytes()).expect("cannot write to stdout");
+        stdout.flush().expect("could not flush");
+    }
+    fn terminal_ids_directly_left_of(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        if terminal_to_check.x_coords == 0 {
+            return None;
+        }
+        for (pid, terminal) in self.terminals.iter() {
+            if terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords - 1 {
+                ids.push(*pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_right_of(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        for (pid, terminal) in self.terminals.iter() {
+            if terminal.x_coords == terminal_to_check.x_coords + terminal_to_check.display_cols + 1 {
+                ids.push(*pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_below(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        for (pid, terminal) in self.terminals.iter() {
+            if terminal.y_coords == terminal_to_check.y_coords + terminal_to_check.display_rows + 1 {
+                ids.push(*pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_above(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        for (pid, terminal) in self.terminals.iter() {
+            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
+                ids.push(*pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_above_with_same_left_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut left_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.x_coords == terminal_to_check.x_coords)
+            .collect();
+        left_aligned_terminals.sort_by(|a, b| { b.y_coords.cmp(&a.y_coords)});
+
+        for terminal in left_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_below_with_same_left_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut left_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.x_coords == terminal_to_check.x_coords)
+            .collect();
+        left_aligned_terminals.sort_by(|a, b| { a.y_coords.cmp(&b.y_coords)});
+
+        for terminal in left_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal_to_check.y_coords + terminal_to_check.display_rows + 1 == terminal.y_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_above_with_same_right_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut right_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords + terminal_to_check.display_cols)
+            .collect();
+        right_aligned_terminals.sort_by(|a, b| { b.y_coords.cmp(&a.y_coords)});
+
+        for terminal in right_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal.y_coords + terminal.display_rows + 1 == terminal_to_check.y_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_below_with_same_right_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut right_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.x_coords + terminal.display_cols == terminal_to_check.x_coords + terminal_to_check.display_cols)
+            .collect();
+        right_aligned_terminals.sort_by(|a, b| { a.y_coords.cmp(&b.y_coords)});
+
+        for terminal in right_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal_to_check.y_coords + terminal_to_check.display_rows + 1 == terminal.y_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_to_the_left_with_same_top_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut top_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.y_coords == terminal_to_check.y_coords)
+            .collect();
+        top_aligned_terminals.sort_by(|a, b| { b.x_coords.cmp(&a.x_coords)});
+
+        for terminal in top_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal.x_coords + terminal.display_cols + 1 == terminal_to_check.x_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_to_the_left_with_same_bottom_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut bottom_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.y_coords + terminal.display_rows == terminal_to_check.y_coords + terminal_to_check.display_rows)
+            .collect();
+        bottom_aligned_terminals.sort_by(|a, b| { b.x_coords.cmp(&a.x_coords)});
+
+        for terminal in bottom_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal.x_coords + terminal.display_cols + 1 == terminal_to_check.x_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_to_the_right_with_same_top_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut top_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.y_coords == terminal_to_check.y_coords)
+            .collect();
+        top_aligned_terminals.sort_by(|a, b| { a.x_coords.cmp(&b.x_coords)});
+
+        for terminal in top_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal_to_check.x_coords + terminal_to_check.display_cols + 1 == terminal.x_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    fn terminal_ids_directly_to_the_right_with_same_bottom_alignment(&self, id: &RawFd) -> Option<Vec<RawFd>> {
+        let mut ids = vec![];
+        let terminal_to_check = self.terminals.get(id).unwrap();
+        let mut bottom_aligned_terminals: Vec<&TerminalOutput> = self.terminals
+            .keys()
+            .map(|t_id| self.terminals.get(&t_id).unwrap())
+            .filter(|terminal| terminal.pid != *id && terminal.y_coords + terminal.display_rows == terminal_to_check.y_coords + terminal_to_check.display_rows)
+            .collect();
+        bottom_aligned_terminals.sort_by(|a, b| { a.x_coords.cmp(&b.x_coords)});
+
+        for terminal in bottom_aligned_terminals {
+            let terminal_to_check = ids
+                .last()
+                .and_then(|id| self.terminals.get(id))
+                .unwrap_or(terminal_to_check);
+            if terminal_to_check.x_coords + terminal_to_check.display_cols + 1 == terminal.x_coords {
+                ids.push(terminal.pid);
+            }
+        }
+        if ids.is_empty() {
+            None
+        } else {
+            Some(ids)
+        }
+    }
+    pub fn resize_left (&mut self) {
+        // TODO: find out by how much we actually reduced and only reduce by that much
+        let count = 10;
+        if let Some(active_terminal_id) = self.get_active_terminal_id() {
+            let terminals_to_the_left = self.terminal_ids_directly_left_of(&active_terminal_id);
+            let terminals_to_the_right = self.terminal_ids_directly_right_of(&active_terminal_id);
+            match (terminals_to_the_left, terminals_to_the_right) {
+                (_, Some(mut terminals_to_the_right)) => {
+                    // reduce to the left
+                    let terminal_borders_to_the_right: HashSet<u16> = terminals_to_the_right.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
+                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_right_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut upper_resize_border = 0;
+                            for terminal in &t {
+                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
+                                if terminal_borders_to_the_right.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
+                                    upper_resize_border = lower_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords >= upper_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, upper_resize_border))
+                        });
+                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_right_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut lower_resize_border = self.full_screen_ws.ws_row;
+                            for terminal in &t {
+                                let upper_terminal_boundary = terminal.y_coords;
+                                if terminal_borders_to_the_right.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
+                                    lower_resize_border = upper_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords + terminal.display_rows <= lower_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, lower_resize_border))
+                        });
+                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
+                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
+                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
+                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
+
+                    active_terminal.reduce_width_left(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_to_the_right.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
+                    });
+                    for terminal_id in terminals_to_the_right {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.increase_width_left(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_above) = terminals_above {
+                        for terminal_id in terminals_above.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_width_left(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_below) = terminals_below {
+                        for terminal_id in terminals_below.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_width_left(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (Some(mut terminals_to_the_left), None) => {
+                    // increase to the left 
+                    let terminal_borders_to_the_left: HashSet<u16> = terminals_to_the_left.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
+                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_left_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut upper_resize_border = 0;
+                            for terminal in &t {
+                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
+                                if terminal_borders_to_the_left.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
+                                    upper_resize_border = lower_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords >= upper_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, upper_resize_border))
+                        });
+                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_left_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut lower_resize_border = self.full_screen_ws.ws_row;
+                            for terminal in &t {
+                                let upper_terminal_boundary = terminal.y_coords;
+                                if terminal_borders_to_the_left.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
+                                    lower_resize_border = upper_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords + terminal.display_rows <= lower_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, lower_resize_border))
+                        });
+                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
+                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
+                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
+                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
+
+                    active_terminal.increase_width_left(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_to_the_left.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
+                    });
+                    for terminal_id in terminals_to_the_left {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.reduce_width_left(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_above) = terminals_above {
+                        for terminal_id in terminals_above.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_width_left(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_below) = terminals_below {
+                        for terminal_id in terminals_below.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_width_left(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (None, None) => {}
+            }
+            self.render();
+        }
+    }
+    pub fn resize_right (&mut self) {
+        let count = 10;
+        if let Some(active_terminal_id) = self.get_active_terminal_id() {
+            let terminals_to_the_left = self.terminal_ids_directly_left_of(&active_terminal_id);
+            let terminals_to_the_right = self.terminal_ids_directly_right_of(&active_terminal_id);
+            match (terminals_to_the_left, terminals_to_the_right) {
+                (_, Some(mut terminals_to_the_right)) => {
+                    // increase to the right
+                    let terminal_borders_to_the_right: HashSet<u16> = terminals_to_the_right.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
+                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_right_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut upper_resize_border = 0;
+                            for terminal in &t {
+                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
+                                if terminal_borders_to_the_right.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
+                                    upper_resize_border = lower_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords >= upper_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, upper_resize_border))
+                        });
+                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_right_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut lower_resize_border = self.full_screen_ws.ws_row;
+                            for terminal in &t {
+                                let upper_terminal_boundary = terminal.y_coords;
+                                if terminal_borders_to_the_right.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
+                                    lower_resize_border = upper_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords + terminal.display_rows <= lower_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, lower_resize_border))
+                        });
+                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
+                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
+                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
+                        None => (None, None),
+                    };
+
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
+                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
+
+                    active_terminal.increase_width_right(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_to_the_right.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
+                    });
+                    for terminal_id in terminals_to_the_right {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.reduce_width_right(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_above) = terminals_above {
+                        for terminal_id in terminals_above.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_width_right(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_below) = terminals_below {
+                        for terminal_id in terminals_below.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_width_right(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (Some(mut terminals_to_the_left), None) => {
+                    // reduce to the right
+                    let terminal_borders_to_the_left: HashSet<u16> = terminals_to_the_left.iter().map(|t| self.terminals.get(t).unwrap().y_coords).collect();
+                    let terminals_above_and_upper_resize_border = self.terminal_ids_directly_above_with_same_left_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut upper_resize_border = 0;
+                            for terminal in &t {
+                                let lower_terminal_boundary = terminal.y_coords + terminal.display_rows;
+                                if terminal_borders_to_the_left.get(&(lower_terminal_boundary + 1)).is_some() && upper_resize_border < lower_terminal_boundary {
+                                    upper_resize_border = lower_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords >= upper_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, upper_resize_border))
+                        });
+                    let terminals_below_and_lower_resize_border = self.terminal_ids_directly_below_with_same_left_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut lower_resize_border = self.full_screen_ws.ws_row;
+                            for terminal in &t {
+                                let upper_terminal_boundary = terminal.y_coords;
+                                if terminal_borders_to_the_left.get(&upper_terminal_boundary).is_some() && lower_resize_border > upper_terminal_boundary {
+                                    lower_resize_border = upper_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.y_coords + terminal.display_rows <= lower_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, lower_resize_border))
+                        });
+                    let (terminals_above, upper_resize_border) = match terminals_above_and_upper_resize_border {
+                        Some((terminals_above, upper_resize_border)) => (Some(terminals_above), Some(upper_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_below, lower_resize_border) = match terminals_below_and_lower_resize_border {
+                        Some((terminals_below, lower_resize_border)) => (Some(terminals_below), Some(lower_resize_border)),
+                        None => (None, None),
+                    };
+
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let upper_resize_border = upper_resize_border.unwrap_or(active_terminal.y_coords);
+                    let lower_resize_border = lower_resize_border.unwrap_or(active_terminal.y_coords + active_terminal.display_rows);
+
+                    active_terminal.reduce_width_right(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_to_the_left.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.y_coords >= upper_resize_border && terminal.y_coords + terminal.display_rows <= lower_resize_border
+                    });
+                    for terminal_id in terminals_to_the_left {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.increase_width_right(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_above) = terminals_above {
+                        for terminal_id in terminals_above.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_width_right(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_below) = terminals_below {
+                        for terminal_id in terminals_below.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_width_right(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (None, None) => {}
+            }
+            self.render();
+        }
+    }
+    pub fn resize_down (&mut self) {
+        // TODO: find out by how much we actually reduced and only reduce by that much
+        let count = 2;
+        if let Some(active_terminal_id) = self.get_active_terminal_id() {
+            let terminals_below = self.terminal_ids_directly_below(&active_terminal_id);
+            let terminals_above = self.terminal_ids_directly_above(&active_terminal_id);
+            match (terminals_below, terminals_above) {
+                (_, Some(mut terminals_above)) => {
+                    // reduce down
+                    let terminal_borders_above: HashSet<u16> = terminals_above.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
+                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_top_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut left_resize_border = 0;
+                            for terminal in &t {
+                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
+                                if terminal_borders_above.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
+                                    left_resize_border = right_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords >= left_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, left_resize_border))
+                        });
+                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_top_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut right_resize_border = self.full_screen_ws.ws_col;
+                            for terminal in &t {
+                                let left_terminal_boundary = terminal.x_coords;
+                                if terminal_borders_above.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
+                                    right_resize_border = left_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords + terminal.display_cols <= right_resize_border 
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, right_resize_border))
+                        });
+                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
+                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
+                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
+                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
+
+                    active_terminal.reduce_height_down(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_above.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border
+                    });
+                    for terminal_id in terminals_above {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.increase_height_down(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_to_the_left) = terminals_to_the_left {
+                        for terminal_id in terminals_to_the_left.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_height_down(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_to_the_right) = terminals_to_the_right {
+                        for terminal_id in terminals_to_the_right.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_height_down(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (Some(mut terminals_below), None) => {
+                    // increase down
+                    let terminal_borders_below: HashSet<u16> = terminals_below.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
+                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_bottom_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut left_resize_border = 0;
+                            for terminal in &t {
+                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
+                                if terminal_borders_below.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
+                                    left_resize_border = right_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords >= left_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, left_resize_border))
+                        });
+                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_bottom_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut right_resize_border = self.full_screen_ws.ws_col;
+                            for terminal in &t {
+                                let left_terminal_boundary = terminal.x_coords;
+                                if terminal_borders_below.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
+                                    right_resize_border = left_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords + terminal.display_cols <= right_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, right_resize_border))
+                        });
+                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
+                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
+                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
+                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
+
+                    active_terminal.increase_height_down(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_below.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border 
+                    });
+                    for terminal_id in terminals_below {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.reduce_height_down(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_to_the_left) = terminals_to_the_left {
+                        for terminal_id in terminals_to_the_left.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_height_down(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_to_the_right) = terminals_to_the_right {
+                        for terminal_id in terminals_to_the_right.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_height_down(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (None, None) => {}
+            }
+            self.render();
+        }
+    }
+    pub fn resize_up (&mut self) {
+        // TODO: find out by how much we actually reduced and only reduce by that much
+        let count = 2;
+        if let Some(active_terminal_id) = self.get_active_terminal_id() {
+            let terminals_below = self.terminal_ids_directly_below(&active_terminal_id);
+            let terminals_above = self.terminal_ids_directly_above(&active_terminal_id);
+            match (terminals_below, terminals_above) {
+                (_, Some(mut terminals_above)) => {
+                    // reduce down
+                    let terminal_borders_above: HashSet<u16> = terminals_above.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
+                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_top_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut left_resize_border = 0;
+                            for terminal in &t {
+                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
+                                if terminal_borders_above.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
+                                    left_resize_border = right_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords >= left_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, left_resize_border))
+                        });
+                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_top_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut right_resize_border = self.full_screen_ws.ws_col;
+                            for terminal in &t {
+                                let left_terminal_boundary = terminal.x_coords;
+                                if terminal_borders_above.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
+                                    right_resize_border = left_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords + terminal.display_cols <= right_resize_border 
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, right_resize_border))
+                        });
+                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
+                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
+                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
+                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols);
+
+                    active_terminal.increase_height_up(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_above.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border
+                    });
+                    for terminal_id in terminals_above {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.reduce_height_up(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_to_the_left) = terminals_to_the_left {
+                        for terminal_id in terminals_to_the_left.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_height_up(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_to_the_right) = terminals_to_the_right {
+                        for terminal_id in terminals_to_the_right.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.increase_height_up(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (Some(mut terminals_below), None) => {
+                    // increase down
+                    let terminal_borders_below: HashSet<u16> = terminals_below.iter().map(|t| self.terminals.get(t).unwrap().x_coords).collect();
+                    let terminals_to_the_left_and_left_resize_border = self.terminal_ids_directly_to_the_left_with_same_bottom_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut left_resize_border = 0;
+                            for terminal in &t {
+                                let right_terminal_boundary = terminal.x_coords + terminal.display_cols;
+                                if terminal_borders_below.get(&(right_terminal_boundary + 1)).is_some() && left_resize_border < right_terminal_boundary {
+                                    left_resize_border = right_terminal_boundary + 1;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords >= left_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, left_resize_border))
+                        });
+                    let terminals_to_the_right_and_right_resize_border = self.terminal_ids_directly_to_the_right_with_same_bottom_alignment(&active_terminal_id)
+                        .and_then(|t| {
+                            let terminals: Vec<&TerminalOutput> = t.iter().map(|t| self.terminals.get(t).unwrap()).collect();
+                            Some(terminals)
+                        })
+                        .and_then(|mut t| {
+                            let mut right_resize_border = self.full_screen_ws.ws_col;
+                            for terminal in &t {
+                                let left_terminal_boundary = terminal.x_coords;
+                                if terminal_borders_below.get(&left_terminal_boundary).is_some() && right_resize_border > left_terminal_boundary {
+                                    right_resize_border = left_terminal_boundary;
+                                }
+                            }
+                            t.retain(|terminal| {
+                                terminal.x_coords + terminal.display_cols <= right_resize_border
+                            });
+                            let terminal_ids: Vec<RawFd> = t.iter().map(|t| t.pid).collect();
+                            Some((terminal_ids, right_resize_border))
+                        });
+                    let (terminals_to_the_left, left_resize_border) = match terminals_to_the_left_and_left_resize_border {
+                        Some((terminals_to_the_left, left_resize_border)) => (Some(terminals_to_the_left), Some(left_resize_border)),
+                        None => (None, None),
+                    };
+                    let (terminals_to_the_right, right_resize_border) = match terminals_to_the_right_and_right_resize_border {
+                        Some((terminals_to_the_right, right_resize_border)) => (Some(terminals_to_the_right), Some(right_resize_border)),
+                        None => (None, None),
+                    };
+                    let active_terminal = self.terminals.get_mut(&active_terminal_id).unwrap();
+                    let left_resize_border = left_resize_border.unwrap_or(active_terminal.x_coords);
+                    let right_resize_border = right_resize_border.unwrap_or(active_terminal.x_coords + active_terminal.display_cols); // TODO: + 1?
+
+                    active_terminal.reduce_height_up(count);
+                    self.os_api.set_terminal_size_using_fd(
+                        active_terminal.pid,
+                        active_terminal.display_cols,
+                        active_terminal.display_rows
+                    );
+
+                    terminals_below.retain(|t| {
+                        let terminal = self.terminals.get(t).unwrap();
+                        terminal.x_coords >= left_resize_border && terminal.x_coords + terminal.display_cols <= right_resize_border 
+                    });
+                    for terminal_id in terminals_below {
+                        let terminal = self.terminals.get_mut(&terminal_id).unwrap();
+                        terminal.increase_height_up(count);
+                        self.os_api.set_terminal_size_using_fd(
+                            terminal.pid,
+                            terminal.display_cols,
+                            terminal.display_rows
+                        );
+                    }
+
+                    if let Some(terminals_to_the_left) = terminals_to_the_left {
+                        for terminal_id in terminals_to_the_left.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_height_up(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+
+                    if let Some(terminals_to_the_right) = terminals_to_the_right {
+                        for terminal_id in terminals_to_the_right.iter() {
+                            let terminal = self.terminals.get_mut(terminal_id).unwrap();
+                            terminal.reduce_height_up(count);
+                            self.os_api.set_terminal_size_using_fd(
+                                terminal.pid,
+                                terminal.display_cols,
+                                terminal.display_rows
+                            );
+                        }
+                    }
+                },
+                (None, None) => {}
+            }
+            self.render();
+        }
+    }
+    pub fn move_focus(&mut self) {
+        if self.terminals.is_empty() {
+            return;
+        }
+        let active_terminal_id = self.get_active_terminal_id().unwrap();
+        let terminal_ids: Vec<RawFd> = self.terminals.keys().copied().collect(); // TODO: better, no allocations
+        let first_terminal = terminal_ids.get(0).unwrap();
+        let active_terminal_id_position = terminal_ids.iter().position(|id| id == &active_terminal_id).unwrap();
+        if let Some(next_terminal) = terminal_ids.get(active_terminal_id_position + 1) {
+            self.active_terminal = Some(*next_terminal);
+        } else {
+            self.active_terminal = Some(*first_terminal);
+        }
+        self.render();
+    }
+}
diff --git a/src/terminal_pane.rs b/src/terminal_pane.rs
new file mode 100644
index 00000000..4e26c435
--- /dev/null
+++ b/src/terminal_pane.rs
@@ -0,0 +1,595 @@
+use ::std::fmt::{self, Display, Formatter};
+use ::std::cmp::max;
+use ::std::collections::VecDeque;
+use ::std::os::unix::io::RawFd;
+use ::nix::pty::Winsize;
+use ::vte::Perform;
+
+use crate::VteEvent;
+
+const DEBUGGING: bool = false;
+const EMPTY_TERMINAL_CHARACTER: TerminalCharacter = TerminalCharacter { character: ' ', ansi_code: None };
+
+#[derive(Clone)]
+pub struct TerminalCharacter {
+    pub character: char,
+    pub ansi_code: Option<String>,
+}
+
+impl PartialEq for TerminalCharacter {
+    fn eq(&self, other: &Self) -> bool {
+        match (&self.ansi_code, &other.ansi_code) {
+            (Some(self_code), Some(other_code)) => {
+                self_code == other_code && self.character == other.character
+            },
+            (None, None) => {
+                self.character == other.character
+            }
+            _ => {
+                false
+            }
+        }
+    }
+}
+
+impl Eq for TerminalCharacter {}
+
+impl TerminalCharacter {
+    pub fn new (character: char) -> Self {
+        TerminalCharacter {
+            character,
+            ansi_code: None
+        }
+    }
+    pub fn ansi_code(mut self, ansi_code: String) -> Self {
+        self.ansi_code = Some(ansi_code);
+        self
+    }
+}
+
+
+impl Display for TerminalCharacter {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match &self.ansi_code {
+            Some(code) => write!(f, "{}{}", code, self.character),
+            None => write!(f, "{}", self.character)
+        }
+    }
+}
+
+impl ::std::fmt::Debug for TerminalCharacter {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.character)
+    }
+}
+
+pub struct TerminalOutput {
+    pub pid: RawFd,
+    pub characters: Vec<TerminalCharacter>,
+    pub display_rows: u16,
+    pub display_cols: u16,
+    pub should_render: bool,
+    pub x_coords: u16,
+    pub y_coords: u16,
+    cursor_position: usize,
+    newline_indices: Vec<usize>, // canonical line breaks we get from the vt interpreter
+    linebreak_indices: Vec<usize>, // linebreaks from line wrapping
+    pending_ansi_code: Option<String>, // this is used eg. in a carriage return, where we need to preserve the style
+}
+
+impl TerminalOutput {
+    pub fn new (pid: RawFd, ws: Winsize, x_coords: u16, y_coords: u16) -> TerminalOutput {
+        TerminalOutput {
+            pid,
+            characters: vec![],
+            cursor_position: 0,
+            newline_indices: Vec::new(),
+            linebreak_indices: Vec::new(),
+            display_rows: ws.ws_row,
+            display_cols: ws.ws_col,
+            should_render: true,
+            pending_ansi_code: None,
+            x_coords,
+            y_coords,
+        }
+    }
+    pub fn handle_event(&mut self, event: VteEvent) {
+        self.should_render = true; // TODO: more accurately
+        match event {
+            VteEvent::Print(c) => {
+                self.print(c);
+            },
+            VteEvent::Execute(byte) => {
+                self.execute(byte);
+            },
+            VteEvent::Hook(params, intermediates, ignore, c) => {
+                self.hook(&params, &intermediates, ignore, c);
+            },
+            VteEvent::Put(byte) => {
+                self.put(byte);
+            },
+            VteEvent::Unhook => {
+                self.unhook();
+            },
+            VteEvent::OscDispatch(params, bell_terminated) => {
+                let params: Vec<&[u8]> = params.iter().map(|p| &p[..]).collect();
+                self.osc_dispatch(&params[..], bell_terminated);
+            },
+            VteEvent::CsiDispatch(params, intermediates, ignore, c) => {
+                self.csi_dispatch(&params, &intermediates, ignore, c);
+            },
+            VteEvent::EscDispatch(intermediates, ignore, byte) => {
+                self.esc_dispatch(&intermediates, ignore, byte);
+            }
+        }
+    }
+    pub fn reduce_width_right(&mut self, count: u16) {
+        self.x_coords += count;
+        self.display_cols -= count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn reduce_width_left(&mut self, count: u16) {
+        self.display_cols -= count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn increase_width_left(&mut self, count: u16) {
+        self.x_coords -= count;
+        self.display_cols += count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn increase_width_right(&mut self, count: u16) {
+        self.display_cols += count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn reduce_height_down(&mut self, count: u16) {
+        self.y_coords += count;
+        self.display_rows -= count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn increase_height_down(&mut self, count: u16) {
+        self.display_rows += count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn increase_height_up(&mut self, count: u16) {
+        self.y_coords -= count;
+        self.display_rows += count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn reduce_height_up(&mut self, count: u16) {
+        self.display_rows -= count;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    pub fn change_size(&mut self, ws: &Winsize) {
+        self.display_cols = ws.ws_col;
+        self.display_rows = ws.ws_row;
+        self.reflow_lines();
+        self.should_render = true;
+    }
+    fn reflow_lines (&mut self) {
+        self.linebreak_indices.clear();
+
+        let mut newline_indices = self.newline_indices.iter();
+        let mut next_newline_index = newline_indices.next();
+
+        let mut x: u64 = 0;
+        for (i, _c) in self.characters.iter().enumerate() {
+            if next_newline_index == Some(&i) {
+                x = 0;
+                next_newline_index = newline_indices.next();
+            } else if x == self.display_cols as u64 && i <= self.cursor_position {
+                self.linebreak_indices.push(i);
+                x = 0;
+            }
+            x += 1;
+        }
+    }
+    pub fn buffer_as_vte_output(&mut self) -> Option<String> {
+        if self.should_render {
+            let mut vte_output = String::new();
+            let buffer_lines = &self.read_buffer_as_lines();
+            let display_cols = &self.display_cols;
+            for (row, line) in buffer_lines.iter().enumerate() {
+                vte_output.push_str(&format!("\u{1b}[{};{}H\u{1b}[m", self.y_coords as usize + row + 1, self.x_coords + 1)); // goto row/col
+                for (col, t_character) in line.iter().enumerate() {
+                    if (col as u16) < *display_cols {
+                        // in some cases (eg. while resizing) some characters will spill over
+                        // before they are corrected by the shell (for the prompt) or by reflowing
+                        // lines
+                        vte_output.push_str(&t_character.to_string());
+                    }
+                }
+            }
+            self.should_render = false;
+            Some(vte_output)
+        } else {
+            None
+        }
+    }
+    pub fn read_buffer_as_lines (&self) -> Vec<Vec<&TerminalCharacter>> {
+        if DEBUGGING {
+            return vec![];
+        }
+        if self.characters.len() == 0 {
+            let mut output = vec![];
+            let mut empty_line = vec![];
+            for _ in 0..self.display_cols {
+                empty_line.push(&EMPTY_TERMINAL_CHARACTER);
+            }
+            for _ in 0..self.display_rows as usize {
+                output.push(Vec::from(empty_line.clone()));
+            }
+            return output
+        }
+        let mut output: VecDeque<Vec<&TerminalCharacter>> = VecDeque::new();
+        let mut i = self.characters.len();
+        let mut current_line: VecDeque<&TerminalCharacter> = VecDeque::new();
+        
+        let mut newline_indices = self.newline_indices.iter().rev();
+        let mut linebreak_indices = self.linebreak_indices.iter().rev();
+
+        let mut next_newline_index = newline_indices.next();
+        let mut next_linebreak_index = linebreak_indices.next();
+
+        loop {
+            i -= 1;
+            if let Some(newline_index) = next_newline_index {
+                if *newline_index == i + 1 {
+                    // pad line
+                    if current_line.len() > 0 {
+                        for _ in current_line.len()..self.display_cols as usize {
+                            current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
+                        }
+                        output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
+                    }
+                    next_newline_index = newline_indices.next();
+                }
+            }
+            if let Some(linebreak_index) = next_linebreak_index {
+                if *linebreak_index == i + 1 {
+                    // pad line
+                    if current_line.len() > 0 {
+                        for _ in current_line.len()..self.display_cols as usize {
+                            current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
+                        }
+                        output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
+                    }
+                    next_linebreak_index = linebreak_indices.next();
+                }
+            }
+            if output.len() == self.display_rows as usize {
+                if current_line.len() > 0 {
+                    for _ in current_line.len()..self.display_cols as usize {
+                        current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
+                    }
+                    output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
+                }
+                break;
+            }
+            let terminal_character = self.characters.get(i).unwrap();
+            current_line.push_front(terminal_character);
+            if i == 0 {
+                if current_line.len() > 0 {
+                    for _ in current_line.len()..self.display_cols as usize {
+                        current_line.push_back(&EMPTY_TERMINAL_CHARACTER);
+                    }
+                    output.push_front(Vec::from(current_line.drain(..).collect::<Vec<&TerminalCharacter>>()));
+                }
+                break;
+            }
+        }
+        if output.len() < self.display_rows as usize {
+            let mut empty_line = vec![];
+            for _ in 0..self.display_cols {
+                empty_line.push(&EMPTY_TERMINAL_CHARACTER);
+            }
+            for _ in output.len()..self.display_rows as usize {
+                output.push_front(Vec::from(empty_line.clone()));
+            }
+        }
+
+        Vec::from(output)
+    }
+    pub fn cursor_position_in_last_line (&self) -> usize {
+        if self.cursor_position <= self.characters.len() {
+            let start_of_last_line = self.index_of_beginning_of_last_line();
+            if self.cursor_position < start_of_last_line {
+                // TODO: why does this happen?
+                return self.display_cols as usize
+            };
+            let difference_from_last_newline = self.cursor_position - start_of_last_line;
+            difference_from_last_newline
+        } else {
+            self.display_cols as usize
+        }
+    }
+    pub fn cursor_coordinates (&self) -> (usize, usize) { // (x, y)
+        let mut lines_from_end = 0;
+
+        let mut newline_indices = self.newline_indices.iter().rev();
+        let mut linebreak_indices = self.linebreak_indices.iter().rev();
+
+        let mut next_newline_index = newline_indices.next().unwrap_or(&0);
+        let mut next_linebreak_index = linebreak_indices.next().unwrap_or(&0);
+
+        let next_line_start = loop {
+            let next_line_start = ::std::cmp::max(*next_newline_index, *next_linebreak_index);
+            if self.cursor_position >= next_line_start {
+                break next_line_start;
+            }
+            if next_line_start == *next_newline_index {
+                next_newline_index = newline_indices.next().unwrap_or(&0);
+                lines_from_end += 1;
+            }
+            if next_line_start == *next_linebreak_index {
+                next_linebreak_index = linebreak_indices.next().unwrap_or(&0);
+                lines_from_end += 1;
+            }
+        };
+        let y = self.display_rows - lines_from_end; // TODO: this might overflow, fix when introducing scrolling
+        let x = self.cursor_position - next_line_start;
+        (x, y as usize)
+    }
+    fn index_of_beginning_of_last_line (&self) -> usize {
+        let last_newline_index = if self.newline_indices.is_empty() {
+            None
+        } else {
+            // return last
+            Some(*self.newline_indices.last().unwrap())
+        };
+        let last_linebreak_index = if self.linebreak_indices.is_empty() {
+            None
+        } else {
+            // return last
+            Some(*self.linebreak_indices.last().unwrap())
+        };
+        match (last_newline_index, last_linebreak_index) {
+            (Some(last_newline_index), Some(last_linebreak_index)) => {
+                max(last_newline_index, last_linebreak_index)
+            },
+            (None, Some(last_linebreak_index)) => last_linebreak_index,
+            (Some(last_newline_index), None) => last_newline_index,
+            (None, None) => 0
+        }
+    }
+    fn index_of_beginning_of_last_canonical_line (&self) -> usize {
+        if self.newline_indices.is_empty() {
+            0
+        } else {
+            // return last
+            *self.newline_indices.last().unwrap()
+        }
+    }
+    fn index_of_beginning_of_line (&self, index_in_line: usize) -> usize {
+        let last_newline_index = if self.newline_indices.is_empty() {
+            None
+        } else {
+            // return last less than index_in_line
+            let last_newline_index = *self.newline_indices.last().unwrap();
+            if last_newline_index <= index_in_line {
+                Some(last_newline_index)
+            } else {
+                let mut last_newline_index = 0;
+                for n_i in self.newline_indices.iter() {
+                    if *n_i > last_newline_index && *n_i <= index_in_line {
+                        last_newline_index = *n_i;
+                    } else if *n_i > index_in_line {
+                        break;
+                    }
+                }
+                Some(last_newline_index)
+            }
+        };
+        let last_linebreak_index = if self.linebreak_indices.is_empty() {
+            None
+        } else {
+            // return last less than index_in_line
+            let last_linebreak_index = *self.linebreak_indices.last().unwrap();
+            if last_linebreak_index <= index_in_line {
+                Some(last_linebreak_index)
+            } else {
+                let mut last_linebreak_index = 0;
+                for l_i in self.linebreak_indices.iter() {
+                    if *l_i > last_linebreak_index && *l_i <= index_in_line {
+                        last_linebreak_index = *l_i;
+                    } else if *l_i > index_in_line {
+                        break;
+                    }
+                }
+                Some(last_linebreak_index)
+            }
+        };
+        match (last_newline_index, last_linebreak_index) {
+            (Some(last_newline_index), Some(last_linebreak_index)) => {
+                max(last_newline_index, last_linebreak_index)
+            },
+            (None, Some(last_linebreak_index)) => last_linebreak_index,
+            (Some(last_newline_index), None) => last_newline_index,
+            (None, None) => 0
+        }
+    }
+    fn add_newline (&mut self) {
+        self.newline_indices.push(self.characters.len());
+        self.cursor_position = self.characters.len();
+        self.should_render = true;
+        self.pending_ansi_code = None;
+    }
+    fn move_to_beginning_of_line (&mut self) {
+        let last_newline_index = if self.newline_indices.is_empty() {
+            0
+        } else {
+            *self.newline_indices.last().unwrap()
+        };
+        self.cursor_position = last_newline_index;
+        self.should_render = true;
+    }
+}
+
+impl vte::Perform for TerminalOutput {
+    fn print(&mut self, c: char) {
+        if DEBUGGING {
+            println!("\r[print] {:?}", c);
+        } else {
+            let mut terminal_character = TerminalCharacter::new(c);
+            terminal_character.ansi_code = self.pending_ansi_code.clone();
+            if self.characters.len() == self.cursor_position {
+                self.characters.push(terminal_character);
+
+                let start_of_last_line = self.index_of_beginning_of_line(self.cursor_position);
+                let difference_from_last_newline = self.cursor_position - start_of_last_line;
+                if difference_from_last_newline == self.display_cols as usize {
+                    self.linebreak_indices.push(self.cursor_position);
+                }
+
+            } else if self.characters.len() > self.cursor_position {
+                self.characters.remove(self.cursor_position);
+                self.characters.insert(self.cursor_position, terminal_character);
+            } else {
+                let mut space_character = TerminalCharacter::new(' ');
+                space_character.ansi_code = self.pending_ansi_code.clone();
+                for _ in self.characters.len()..self.cursor_position {
+                    self.characters.push(space_character.clone());
+                };
+                self.characters.push(terminal_character);
+
+                let start_of_last_line = self.index_of_beginning_of_line(self.cursor_position);
+                let difference_from_last_newline = self.cursor_position - start_of_last_line;
+                if difference_from_last_newline == self.display_cols as usize {
+                    self.linebreak_indices.push(self.cursor_position);
+                }
+            }
+            self.cursor_position += 1;
+        }
+    }
+
+    fn execute(&mut self, byte: u8) {
+        if DEBUGGING {
+            if byte == 13 { // 0d, carriage return
+                println!("\rEXECUTE CARRIAGE RETURN");
+            } else if byte == 10 { // 0a, newline
+                println!("\rEXECUTE NEW LINE");
+            } else if byte == 08 { // backspace
+                println!("\rEXECUTE BACKSPACE");
+            } else {
+                println!("\r[execute] {:02x}", byte);
+            }
+        } else {
+            if byte == 13 { // 0d, carriage return
+                self.move_to_beginning_of_line();
+            } else if byte == 08 { // backspace
+                self.cursor_position -= 1;
+            } else if byte == 10 { // 0a, newline
+                self.add_newline();
+            }
+        }
+    }
+
+    fn hook(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
+        if DEBUGGING {
+            println!(
+                "\r[hook] params={:?}, intermediates={:?}, ignore={:?}, char={:?}",
+                params, intermediates, ignore, c
+            );
+        }
+    }
+
+    fn put(&mut self, byte: u8) {
+        if DEBUGGING {
+            println!("\r[put] {:02x}", byte);
+        }
+    }
+
+    fn unhook(&mut self) {
+        if DEBUGGING {
+            println!("\r[unhook]");
+        }
+    }
+
+    fn osc_dispatch(&mut self, params: &[&[u8]], bell_terminated: bool) {
+    // TODO: normalize vec/slices for all of these methods and the enum
+        if DEBUGGING {
+            println!("\r[osc_dispatch] params={:?} bell_terminated={}", params, bell_terminated);
+        }
+    }
+
+    fn csi_dispatch(&mut self, params: &[i64], intermediates: &[u8], ignore: bool, c: char) {
+        if DEBUGGING {
+            println!(
+                "\r[csi_dispatch] params={:?}, intermediates={:?}, ignore={:?}, char={:?}",
+                params, intermediates, ignore, c
+            );
+        } else {
+            if c == 'm' {
+                // change foreground color (only?)
+                if params.len() == 1 && params[0] == 0 {
+                    // eg. \u{1b}[m
+                    self.pending_ansi_code = Some(String::from("\u{1b}[m"));
+                } else {
+                    // eg. \u{1b}[38;5;0m
+                    let param_string = params.iter().map(|p| p.to_string()).collect::<Vec<String>>().join(";");
+                    self.pending_ansi_code = Some(format!("\u{1b}[{}m", param_string));
+                }
+            } else if c == 'C' { // move cursor forward
+                self.cursor_position += params[0] as usize; // TODO: negative value?
+            } else if c == 'K' { // clear line (0 => right, 1 => left, 2 => all)
+                if params[0] == 0 {
+                    if let Some(position_of_first_newline_index_to_delete) = self.newline_indices.iter().position(|&ni| ni > self.cursor_position) {
+                        self.newline_indices.truncate(position_of_first_newline_index_to_delete);
+                    }
+                    if let Some(position_of_first_linebreak_index_to_delete) = self.linebreak_indices.iter().position(|&li| li > self.cursor_position) {
+                        self.newline_indices.truncate(position_of_first_linebreak_index_to_delete);
+                    }
+                    self.characters.truncate(self.cursor_position + 1);
+                }
+                // TODO: implement 1 and 2
+            } else if c == 'J' { // clear all (0 => below, 1 => above, 2 => all, 3 => saved)
+                if params[0] == 0 {
+                    if let Some(position_of_first_newline_index_to_delete) = self.newline_indices.iter().position(|&ni| ni > self.cursor_position) {
+                        self.newline_indices.truncate(position_of_first_newline_index_to_delete);
+                    }
+                    if let Some(position_of_first_linebreak_index_to_delete) = self.linebreak_indices.iter().position(|&li| li > self.cursor_position) {
+                        self.newline_indices.truncate(position_of_first_linebreak_index_to_delete);
+                    }
+                    self.characters.truncate(self.cursor_position + 1);
+                }
+                // TODO: implement 1, 2, and 3
+            } else if c == 'H' { // goto row/col
+                let row = params[0] as usize - 1; // we subtract 1 here because this csi is 1 indexed and we index from 0
+                let col = params[1] as usize - 1;
+
+                match self.newline_indices.get(row as usize) {
+                    Some(index_of_next_row) => {
+                        let index_of_row = index_of_next_row - self.display_cols as usize;
+                        self.cursor_position = index_of_row + col as usize;
+                    }
+                    None => {
+                        let start_of_last_line = self.index_of_beginning_of_last_canonical_line();
+                        let num_of_lines_to_add = row - self.newline_indices.len();
+                        for i in 0..num_of_lines_to_add {
+                            self.newline_indices.push(start_of_last_line + ((i + 1) * self.display_cols as usize));
+                        }
+                        let index_of_row = self.newline_indices.last().unwrap_or(&0); // TODO: better
+                        self.cursor_position = index_of_row + col as usize;
+                    }
+                }
+            }
+        }
+    }
+
+    fn esc_dispatch(&mut self, intermediates: &[u8], ignore: bool, byte: u8) {
+        if DEBUGGING {
+            println!(
+                // "\r[esc_dispatch] intermediates={:?}, ignore={:?}, byte={:02x}",
+                "\r[esc_dispatch] intermediates={:?}, ignore={:?}, byte={:?}",
+                intermediates, ignore, byte
+            );
+        }
+    }
+}