fix(input): properly handle bracketed paste (#810)

* fix(input): properly handle bracketed paste

* style(fmt): make rustfmt happy

4 files changed, 118 insertions, 131 deletions

diff --git a/zellij-client/src/input_handler.rs b/zellij-client/src/input_handler.rs
index 78869fd5..2b89741e 100644
--- a/zellij-client/src/input_handler.rs
+++ b/zellij-client/src/input_handler.rs
@@ -31,7 +31,6 @@ struct InputHandler {
     command_is_executing: CommandIsExecuting,
     send_client_instructions: SenderWithContext<ClientInstruction>,
     should_exit: bool,
-    pasting: bool,
     receive_input_instructions: Receiver<(InputInstruction, ErrorContext)>,
 }
 
@@ -54,7 +53,6 @@ impl InputHandler {
             command_is_executing,
             send_client_instructions,
             should_exit: false,
-            pasting: false,
             receive_input_instructions,
         }
     }
@@ -65,9 +63,6 @@ impl InputHandler {
         let mut err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
         err_ctx.add_call(ContextType::StdinHandler);
         let alt_left_bracket = vec![27, 91];
-        let bracketed_paste_start = vec![27, 91, 50, 48, 48, 126]; // \u{1b}[200~
-        let bracketed_paste_end = vec![27, 91, 50, 48, 49, 126]; // \u{1b}[201
-
         if !self.options.disable_mouse_mode {
             self.os_input.enable_mouse();
         }
@@ -92,12 +87,6 @@ impl InputHandler {
                             if unsupported_key == alt_left_bracket {
                                 let key = Key::Alt('[');
                                 self.handle_key(&key, raw_bytes);
-                            } else if unsupported_key == bracketed_paste_start {
-                                self.pasting = true;
-                                self.handle_unknown_key(raw_bytes);
-                            } else if unsupported_key == bracketed_paste_end {
-                                self.pasting = false;
-                                self.handle_unknown_key(raw_bytes);
                             } else {
                                 // this is a hack because termion doesn't recognize certain keys
                                 // in this case we just forward it to the terminal
@@ -106,6 +95,12 @@ impl InputHandler {
                         }
                     }
                 }
+                Ok((InputInstruction::PastedText(raw_bytes), _error_context)) => {
+                    if self.mode == InputMode::Normal || self.mode == InputMode::Locked {
+                        let action = Action::Write(raw_bytes);
+                        self.dispatch_action(action);
+                    }
+                }
                 Ok((InputInstruction::SwitchToMode(input_mode), _error_context)) => {
                     self.mode = input_mode;
                 }
@@ -121,20 +116,10 @@ impl InputHandler {
     }
     fn handle_key(&mut self, key: &Key, raw_bytes: Vec<u8>) {
         let keybinds = &self.config.keybinds;
-        if self.pasting {
-            // we're inside a paste block, if we're in a mode that allows sending text to the
-            // terminal, send all text directly without interpreting it
-            // otherwise, just discard the input
-            if self.mode == InputMode::Normal || self.mode == InputMode::Locked {
-                let action = Action::Write(raw_bytes);
-                self.dispatch_action(action);
-            }
-        } else {
-            for action in Keybinds::key_to_actions(key, raw_bytes, &self.mode, keybinds) {
-                let should_exit = self.dispatch_action(action);
-                if should_exit {
-                    self.should_exit = true;
-                }
+        for action in Keybinds::key_to_actions(key, raw_bytes, &self.mode, keybinds) {
+            let should_exit = self.dispatch_action(action);
+            if should_exit {
+                self.should_exit = true;
             }
         }
     }
diff --git a/zellij-client/src/lib.rs b/zellij-client/src/lib.rs
index 06f7e32e..45842fec 100644
--- a/zellij-client/src/lib.rs
+++ b/zellij-client/src/lib.rs
@@ -2,6 +2,7 @@ pub mod os_input_output;
 
 mod command_is_executing;
 mod input_handler;
+mod stdin_handler;
 
 use log::info;
 use std::env::current_exe;
@@ -12,15 +13,14 @@ use std::thread;
 
 use crate::{
     command_is_executing::CommandIsExecuting, input_handler::input_loop,
-    os_input_output::ClientOsApi,
+    os_input_output::ClientOsApi, stdin_handler::stdin_loop,
 };
-use termion::input::TermReadEventsAndRaw;
 use zellij_tile::data::InputMode;
 use zellij_utils::{
     channels::{self, ChannelWithContext, SenderWithContext},
     consts::{SESSION_NAME, ZELLIJ_IPC_PIPE},
     errors::{ClientContext, ContextType, ErrorInstruction},
-    input::{actions::Action, config::Config, mouse::MouseEvent, options::Options},
+    input::{actions::Action, config::Config, options::Options},
     ipc::{ClientAttributes, ClientToServerMsg, ExitReason, ServerToClientMsg},
     termion,
 };
@@ -91,9 +91,10 @@ pub enum ClientInfo {
 }
 
 #[derive(Debug, Clone)]
-pub enum InputInstruction {
+pub(crate) enum InputInstruction {
     KeyEvent(termion::event::Event, Vec<u8>),
     SwitchToMode(InputMode),
+    PastedText(Vec<u8>),
 }
 
 pub fn start_client(
@@ -193,44 +194,7 @@ pub fn start_client(
         .spawn({
             let os_input = os_input.clone();
             let send_input_instructions = send_input_instructions.clone();
-            move || loop {
-                let stdin_buffer = os_input.read_from_stdin();
-                for key_result in stdin_buffer.events_and_raw() {
-                    let (key_event, raw_bytes) = key_result.unwrap();
-                    if let termion::event::Event::Mouse(me) = key_event {
-                        let mouse_event = zellij_utils::input::mouse::MouseEvent::from(me);
-                        if let MouseEvent::Hold(_) = mouse_event {
-                            // as long as the user is holding the mouse down (no other stdin, eg.
-                            // MouseRelease) we need to keep sending this instruction to the app,
-                            // because the app itself doesn't have an event loop in the proper
-                            // place
-                            let mut poller = os_input.stdin_poller();
-                            send_input_instructions
-                                .send(InputInstruction::KeyEvent(
-                                    key_event.clone(),
-                                    raw_bytes.clone(),
-                                ))
-                                .unwrap();
-                            loop {
-                                let ready = poller.ready();
-                                if ready {
-                                    break;
-                                }
-                                send_input_instructions
-                                    .send(InputInstruction::KeyEvent(
-                                        key_event.clone(),
-                                        raw_bytes.clone(),
-                                    ))
-                                    .unwrap();
-                            }
-                            continue;
-                        }
-                    }
-                    send_input_instructions
-                        .send(InputInstruction::KeyEvent(key_event, raw_bytes))
-                        .unwrap();
-                }
-            }
+            move || stdin_loop(os_input, send_input_instructions)
         });
 
     let _input_thread = thread::Builder::new()
diff --git a/zellij-client/src/stdin_handler.rs b/zellij-client/src/stdin_handler.rs
new file mode 100644
index 00000000..932550c0
--- /dev/null
+++ b/zellij-client/src/stdin_handler.rs
@@ -0,0 +1,102 @@
+use crate::os_input_output::ClientOsApi;
+use crate::InputInstruction;
+use termion::input::TermReadEventsAndRaw;
+use zellij_utils::channels::SenderWithContext;
+use zellij_utils::input::mouse::MouseEvent;
+use zellij_utils::termion;
+
+fn bracketed_paste_end_position(stdin_buffer: &[u8]) -> Option<usize> {
+    let bracketed_paste_end = vec![27, 91, 50, 48, 49, 126]; // \u{1b}[201
+    let mut bp_position = 0;
+    let mut position = None;
+    for (i, byte) in stdin_buffer.iter().enumerate() {
+        if Some(byte) == bracketed_paste_end.get(bp_position) {
+            position = Some(i);
+            bp_position += 1;
+            if bp_position == bracketed_paste_end.len() - 1 {
+                break;
+            }
+        } else {
+            bp_position = 0;
+            position = None;
+        }
+    }
+    if bp_position == bracketed_paste_end.len() - 1 {
+        position
+    } else {
+        None
+    }
+}
+
+pub(crate) fn stdin_loop(
+    os_input: Box<dyn ClientOsApi>,
+    send_input_instructions: SenderWithContext<InputInstruction>,
+) {
+    let mut pasting = false;
+    let bracketed_paste_start = vec![27, 91, 50, 48, 48, 126]; // \u{1b}[200~
+    loop {
+        let mut stdin_buffer = os_input.read_from_stdin();
+        if pasting
+            || (stdin_buffer.len() > bracketed_paste_start.len()
+                && stdin_buffer
+                    .iter()
+                    .take(bracketed_paste_start.len())
+                    .eq(bracketed_paste_start.iter()))
+        {
+            match bracketed_paste_end_position(&stdin_buffer) {
+                Some(paste_end_position) => {
+                    let pasted_input = stdin_buffer.drain(..=paste_end_position).collect();
+                    send_input_instructions
+                        .send(InputInstruction::PastedText(pasted_input))
+                        .unwrap();
+                    pasting = false;
+                }
+                None => {
+                    send_input_instructions
+                        .send(InputInstruction::PastedText(stdin_buffer))
+                        .unwrap();
+                    pasting = true;
+                    continue;
+                }
+            }
+        }
+        if stdin_buffer.is_empty() {
+            continue;
+        }
+        for key_result in stdin_buffer.events_and_raw() {
+            let (key_event, raw_bytes) = key_result.unwrap();
+            if let termion::event::Event::Mouse(me) = key_event {
+                let mouse_event = zellij_utils::input::mouse::MouseEvent::from(me);
+                if let MouseEvent::Hold(_) = mouse_event {
+                    // as long as the user is holding the mouse down (no other stdin, eg.
+                    // MouseRelease) we need to keep sending this instruction to the app,
+                    // because the app itself doesn't have an event loop in the proper
+                    // place
+                    let mut poller = os_input.stdin_poller();
+                    send_input_instructions
+                        .send(InputInstruction::KeyEvent(
+                            key_event.clone(),
+                            raw_bytes.clone(),
+                        ))
+                        .unwrap();
+                    loop {
+                        let ready = poller.ready();
+                        if ready {
+                            break;
+                        }
+                        send_input_instructions
+                            .send(InputInstruction::KeyEvent(
+                                key_event.clone(),
+                                raw_bytes.clone(),
+                            ))
+                            .unwrap();
+                    }
+                    continue;
+                }
+            }
+            send_input_instructions
+                .send(InputInstruction::KeyEvent(key_event, raw_bytes))
+                .unwrap();
+        }
+    }
+}
diff --git a/zellij-client/src/unit/input_handler_tests.rs b/zellij-client/src/unit/input_handler_tests.rs
index f4beb53a..881c7f63 100644
--- a/zellij-client/src/unit/input_handler_tests.rs
+++ b/zellij-client/src/unit/input_handler_tests.rs
@@ -250,67 +250,3 @@ pub fn move_focus_left_in_normal_mode() {
         "All actions sent to server properly"
     );
 }
-
-#[test]
-pub fn bracketed_paste() {
-    let stdin_events = vec![
-        (
-            commands::BRACKETED_PASTE_START.to_vec(),
-            Event::Unsupported(commands::BRACKETED_PASTE_START.to_vec()),
-        ),
-        (
-            commands::MOVE_FOCUS_LEFT_IN_NORMAL_MODE.to_vec(),
-            Event::Key(Key::Alt('h')),
-        ),
-        (
-            commands::BRACKETED_PASTE_END.to_vec(),
-            Event::Unsupported(commands::BRACKETED_PASTE_END.to_vec()),
-        ),
-        (commands::QUIT.to_vec(), Event::Key(Key::Ctrl('q'))),
-    ];
-    let events_sent_to_server = Arc::new(Mutex::new(vec![]));
-    let command_is_executing = CommandIsExecuting::new();
-    let client_os_api = Box::new(FakeClientOsApi::new(
-        events_sent_to_server.clone(),
-        command_is_executing.clone(),
-    ));
-    let config = Config::from_default_assets().unwrap();
-    let options = Options::default();
-
-    let (send_client_instructions, _receive_client_instructions): ChannelWithContext<
-        ClientInstruction,
-    > = channels::bounded(50);
-    let send_client_instructions = SenderWithContext::new(send_client_instructions);
-
-    let (send_input_instructions, receive_input_instructions): ChannelWithContext<
-        InputInstruction,
-    > = channels::bounded(50);
-    let send_input_instructions = SenderWithContext::new(send_input_instructions);
-    for event in stdin_events {
-        send_input_instructions
-            .send(InputInstruction::KeyEvent(event.1, event.0))
-            .unwrap();
-    }
-
-    let default_mode = InputMode::Normal;
-    input_loop(
-        client_os_api,
-        config,
-        options,
-        command_is_executing,
-        send_client_instructions,
-        default_mode,
-        receive_input_instructions,
-    );
-    let expected_actions_sent_to_server = vec![
-        Action::Write(commands::BRACKETED_PASTE_START.to_vec()),
-        Action::Write(commands::MOVE_FOCUS_LEFT_IN_NORMAL_MODE.to_vec()), // keys were directly written to server and not interpreted
-        Action::Write(commands::BRACKETED_PASTE_END.to_vec()),
-        Action::Quit,
-    ];
-    let received_actions = extract_actions_sent_to_server(events_sent_to_server);
-    assert_eq!(
-        expected_actions_sent_to_server, received_actions,
-        "All actions sent to server properly"
-    );
-}