Add cli paste action (#4817)

* add cli paste action

* add pr

11 files changed, 150 insertions, 15 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 86f472c1..8dcc6894 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -73,6 +73,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 * feat: click to open file-paths in viewport, allow plugins to highlight viewport text (https://github.com/zellij-org/zellij/pull/4802 and https://github.com/zellij-org/zellij/pull/4809)
 * fix: better handle STDIN segmentation with latency (eg. over SSH) (https://github.com/zellij-org/zellij/pull/4623)
 * feat: `zellij subscribe` -> allow to subscribe to pane viewport/scrollback updates from the cli (https://github.com/zellij-org/zellij/pull/4814)
+* feat: `zellij action paste` for pasting large buffers into panes from the command line (https://github.com/zellij-org/zellij/pull/4817)
 
 
 ## [0.43.1] - 2025-08-08
diff --git a/zellij-server/src/route.rs b/zellij-server/src/route.rs
index 540f398f..4289cb6d 100644
--- a/zellij-server/src/route.rs
+++ b/zellij-server/src/route.rs
@@ -277,6 +277,20 @@ pub(crate) fn route_action(
                 ))
                 .with_context(err_context)?;
         },
+        Action::Paste { chars, pane_id } => {
+            senders
+                .send_to_screen(ScreenInstruction::ClearScroll(client_id))
+                .with_context(err_context)?;
+            let bytes = chars.into_bytes();
+            senders
+                .send_to_screen(ScreenInstruction::Paste(
+                    bytes,
+                    pane_id.map(|p| p.into()),
+                    client_id,
+                    Some(NotificationEnd::new(completion_tx)),
+                ))
+                .with_context(err_context)?;
+        },
         Action::SetPaneColor { pane_id, fg, bg } => {
             senders
                 .send_to_screen(ScreenInstruction::SetPaneColor(
diff --git a/zellij-server/src/screen.rs b/zellij-server/src/screen.rs
index c907cfd6..8ebe10c5 100644
--- a/zellij-server/src/screen.rs
+++ b/zellij-server/src/screen.rs
@@ -602,6 +602,7 @@ pub enum ScreenInstruction {
     ResizePaneWithId(ResizeStrategy, PaneId),
     EditScrollbackForPaneWithId(PaneId, Option<NotificationEnd>),
     WriteToPaneId(Vec<u8>, PaneId, Option<NotificationEnd>),
+    Paste(Vec<u8>, Option<PaneId>, ClientId, Option<NotificationEnd>),
     SetPaneColor(
         PaneId,
         Option<String>,
@@ -891,6 +892,7 @@ impl From<&ScreenInstruction> for ScreenContext {
                 ScreenContext::EditScrollbackForPaneWithId
             },
             ScreenInstruction::WriteToPaneId(..) => ScreenContext::WriteToPaneId,
+            ScreenInstruction::Paste(..) => ScreenContext::Paste,
             ScreenInstruction::SetPaneColor(..) => ScreenContext::SetPaneColor,
             ScreenInstruction::WriteKeyToPaneId(..) => ScreenContext::WriteKeyToPaneId,
             ScreenInstruction::CopyTextToClipboard(..) => ScreenContext::CopyTextToClipboard,
@@ -7395,6 +7397,31 @@ pub(crate) fn screen_thread_main(
                 }
                 screen.render(None)?;
             },
+            ScreenInstruction::Paste(bytes, pane_id, client_id, _completion) => {
+                match pane_id {
+                    Some(pane_id) => {
+                        let all_tabs = screen.get_tabs_mut();
+                        for tab in all_tabs.values_mut() {
+                            if tab.has_pane_with_pid(&pane_id) {
+                                tab.paste_to_pane_id(bytes, pane_id, _completion)
+                                    .non_fatal();
+                                break;
+                            }
+                        }
+                    },
+                    None => {
+                        active_tab_and_connected_client_id!(
+                            screen,
+                            client_id,
+                            |tab: &mut Tab, _client_id: ClientId| {
+                                tab.paste_to_active_terminal(bytes, client_id, _completion)
+                                    .non_fatal();
+                            }
+                        );
+                    },
+                }
+                screen.render(None)?;
+            },
             ScreenInstruction::SetPaneColor(pane_id, fg, bg, _completion) => {
                 let all_tabs = screen.get_tabs_mut();
                 for tab in all_tabs.values_mut() {
diff --git a/zellij-server/src/tab/mod.rs b/zellij-server/src/tab/mod.rs
index 7ade6b68..fba48de1 100644
--- a/zellij-server/src/tab/mod.rs
+++ b/zellij-server/src/tab/mod.rs
@@ -2803,6 +2803,35 @@ impl Tab {
         Ok(())
     }
 
+    pub fn paste_to_pane_id(
+        &mut self,
+        bytes: Vec<u8>,
+        pane_id: PaneId,
+        completion: Option<NotificationEnd>,
+    ) -> Result<()> {
+        let bracketed_paste_begin = vec![27, 91, 50, 48, 48, 126];
+        let bracketed_paste_end = vec![27, 91, 50, 48, 49, 126];
+
+        self.write_to_pane_id(&None, bracketed_paste_begin, false, pane_id, None, None)?;
+        self.write_to_pane_id(&None, bytes, false, pane_id, None, None)?;
+        self.write_to_pane_id(&None, bracketed_paste_end, false, pane_id, None, completion)?;
+        Ok(())
+    }
+
+    pub fn paste_to_active_terminal(
+        &mut self,
+        bytes: Vec<u8>,
+        client_id: ClientId,
+        completion: Option<NotificationEnd>,
+    ) -> Result<()> {
+        let err_context = || format!("failed to paste to active terminal for client {client_id}");
+        let active_pane_id = self
+            .get_active_pane_id(client_id)
+            .ok_or_else(|| anyhow!("no active pane for client {client_id}"))
+            .with_context(err_context)?;
+        self.paste_to_pane_id(bytes, active_pane_id, completion)
+    }
+
     pub fn write_to_pane_id(
         &mut self,
         key_with_modifier: &Option<KeyWithModifier>,
diff --git a/zellij-utils/assets/prost_ipc/client_server_contract.rs b/zellij-utils/assets/prost_ipc/client_server_contract.rs
index e7fdd27d..cb420225 100644
--- a/zellij-utils/assets/prost_ipc/client_server_contract.rs
+++ b/zellij-utils/assets/prost_ipc/client_server_contract.rs
@@ -119,7 +119,7 @@ pub struct RgbColor {
 #[allow(clippy::derive_partial_eq_without_eq)]
 #[derive(Clone, PartialEq, ::prost::Message)]
 pub struct Action {
-    #[prost(oneof="action::ActionType", tags="1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108")]
+    #[prost(oneof="action::ActionType", tags="1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109")]
     pub action_type: ::core::option::Option<action::ActionType>,
 }
 /// Nested message and enum types in `Action`.
@@ -343,6 +343,8 @@ pub mod action {
         HideFloatingPanes(super::HideFloatingPanesAction),
         #[prost(message, tag="108")]
         SetPaneColor(super::SetPaneColorAction),
+        #[prost(message, tag="109")]
+        Paste(super::PasteAction),
     }
 }
 // Action message definitions (all 92 variants)
@@ -641,6 +643,14 @@ pub struct WriteCharsToPaneIdAction {
 }
 #[allow(clippy::derive_partial_eq_without_eq)]
 #[derive(Clone, PartialEq, ::prost::Message)]
+pub struct PasteAction {
+    #[prost(string, tag="1")]
+    pub chars: ::prost::alloc::string::String,
+    #[prost(message, optional, tag="2")]
+    pub pane_id: ::core::option::Option<PaneId>,
+}
+#[allow(clippy::derive_partial_eq_without_eq)]
+#[derive(Clone, PartialEq, ::prost::Message)]
 pub struct SwitchToModeAction {
     #[prost(enumeration="InputMode", tag="1")]
     pub input_mode: i32,
diff --git a/zellij-utils/src/cli.rs b/zellij-utils/src/cli.rs
index 63c7777f..4d382477 100644
--- a/zellij-utils/src/cli.rs
+++ b/zellij-utils/src/cli.rs
@@ -694,6 +694,13 @@ pub enum CliAction {
         #[clap(short, long, value_parser)]
         pane_id: Option<String>,
     },
+    /// Paste text to the terminal (using bracketed paste mode).
+    Paste {
+        chars: String,
+        /// The pane_id of the pane, eg. terminal_1, plugin_2 or 3 (equivalent to terminal_3)
+        #[clap(short, long, value_parser)]
+        pane_id: Option<String>,
+    },
     /// Send one or more keys to the terminal (e.g., "Ctrl a", "F1", "Alt Shift b")
     SendKeys {
         /// Keys to send as space-separated strings
diff --git a/zellij-utils/src/client_server_contract/common_types.proto b/zellij-utils/src/client_server_contract/common_types.proto
index e5e661a9..d872d8a6 100644
--- a/zellij-utils/src/client_server_contract/common_types.proto
+++ b/zellij-utils/src/client_server_contract/common_types.proto
@@ -244,6 +244,7 @@ message Action {
     ShowFloatingPanesAction show_floating_panes = 106;
     HideFloatingPanesAction hide_floating_panes = 107;
     SetPaneColorAction set_pane_color = 108;
+    PasteAction paste = 109;
   }
 }
 
@@ -357,6 +358,11 @@ message WriteCharsToPaneIdAction {
   string chars = 2;
 }
 
+message PasteAction {
+  string chars = 1;
+  optional PaneId pane_id = 2;
+}
+
 message SwitchToModeAction {
   InputMode input_mode = 1;
 }
diff --git a/zellij-utils/src/errors.rs b/zellij-utils/src/errors.rs
index 221a7b96..82016f7c 100644
--- a/zellij-utils/src/errors.rs
+++ b/zellij-utils/src/errors.rs
@@ -372,6 +372,7 @@ pub enum ScreenContext {
     ResizePaneWithId,
     EditScrollbackForPaneWithId,
     WriteToPaneId,
+    Paste,
     SetPaneColor,
     WriteKeyToPaneId,
     CopyTextToClipboard,
diff --git a/zellij-utils/src/input/actions.rs b/zellij-utils/src/input/actions.rs
index 5ed8504e..c722e5ff 100644
--- a/zellij-utils/src/input/actions.rs
+++ b/zellij-utils/src/input/actions.rs
@@ -137,6 +137,11 @@ pub enum Action {
         chars: String,
         pane_id: PaneId,
     },
+    /// Paste text using bracketed paste mode, optionally to a specific pane.
+    Paste {
+        chars: String,
+        pane_id: Option<PaneId>,
+    },
     /// Switch to the specified input mode.
     SwitchToMode {
         input_mode: InputMode,
@@ -614,6 +619,29 @@ impl Action {
                 },
                 None => Ok(vec![Action::WriteChars { chars }]),
             },
+            CliAction::Paste { chars, pane_id } => match pane_id {
+                Some(pane_id_str) => {
+                    let parsed_pane_id = PaneId::from_str(&pane_id_str);
+                    match parsed_pane_id {
+                        Ok(parsed_pane_id) => {
+                            Ok(vec![Action::Paste {
+                                chars,
+                                pane_id: Some(parsed_pane_id),
+                            }])
+                        },
+                        Err(_e) => {
+                            Err(format!(
+                                "Malformed pane id: {}, expecting either a bare integer (eg. 1), a terminal pane id (eg. terminal_1) or a plugin pane id (eg. plugin_1)",
+                                pane_id_str
+                            ))
+                        }
+                    }
+                },
+                None => Ok(vec![Action::Paste {
+                    chars,
+                    pane_id: None,
+                }]),
+            },
             CliAction::SendKeys { keys, pane_id } => {
                 let mut actions = Vec::new();
 
diff --git a/zellij-utils/src/ipc/protobuf_conversion.rs b/zellij-utils/src/ipc/protobuf_conversion.rs
index d843dc9d..4c8316d2 100644
--- a/zellij-utils/src/ipc/protobuf_conversion.rs
+++ b/zellij-utils/src/ipc/protobuf_conversion.rs
@@ -792,19 +792,20 @@ impl From<crate::input::actions::Action>
             NewPaneAction, NewStackedPaneAction, NewTabAction, NewTiledPaneAction,
             NewTiledPluginPaneAction, NextSwapLayoutAction, NoOpAction, OverrideLayoutAction,
             PageScrollDownAction, PageScrollUpAction, PaneIdWithPlugin, PaneNameInputAction,
-            PreviousSwapLayoutAction, QueryTabNamesAction, QuitAction, RenamePluginPaneAction,
-            RenameSessionAction, RenameTabAction, RenameTabByIdAction, RenameTerminalPaneAction,
-            ResizeAction, RunAction, SaveSessionAction, ScrollDownAction, ScrollDownAtAction,
-            ScrollToBottomAction, ScrollToTopAction, ScrollUpAction, ScrollUpAtAction,
-            SearchAction, SearchInputAction, SearchToggleOptionAction, SetPaneBorderlessAction,
-            SetPaneColorAction, ShowFloatingPanesAction, SkipConfirmAction, StackPanesAction,
-            StartOrReloadPluginAction, SwitchFocusAction, SwitchModeForAllClientsAction,
-            SwitchSessionAction, SwitchToModeAction, TabNameInputAction, ToggleActiveSyncTabAction,
-            ToggleFloatingPanesAction, ToggleFocusFullscreenAction, ToggleGroupMarkingAction,
-            ToggleMouseModeAction, TogglePaneBorderlessAction, TogglePaneEmbedOrFloatingAction,
-            TogglePaneFramesAction, TogglePaneInGroupAction, TogglePanePinnedAction,
-            ToggleTabAction, UndoRenamePaneAction, UndoRenameTabAction, WriteAction,
-            WriteCharsAction, WriteCharsToPaneIdAction, WriteToPaneIdAction,
+            PasteAction, PreviousSwapLayoutAction, QueryTabNamesAction, QuitAction,
+            RenamePluginPaneAction, RenameSessionAction, RenameTabAction, RenameTabByIdAction,
+            RenameTerminalPaneAction, ResizeAction, RunAction, SaveSessionAction, ScrollDownAction,
+            ScrollDownAtAction, ScrollToBottomAction, ScrollToTopAction, ScrollUpAction,
+            ScrollUpAtAction, SearchAction, SearchInputAction, SearchToggleOptionAction,
+            SetPaneBorderlessAction, SetPaneColorAction, ShowFloatingPanesAction,
+            SkipConfirmAction, StackPanesAction, StartOrReloadPluginAction, SwitchFocusAction,
+            SwitchModeForAllClientsAction, SwitchSessionAction, SwitchToModeAction,
+            TabNameInputAction, ToggleActiveSyncTabAction, ToggleFloatingPanesAction,
+            ToggleFocusFullscreenAction, ToggleGroupMarkingAction, ToggleMouseModeAction,
+            TogglePaneBorderlessAction, TogglePaneEmbedOrFloatingAction, TogglePaneFramesAction,
+            TogglePaneInGroupAction, TogglePanePinnedAction, ToggleTabAction, UndoRenamePaneAction,
+            UndoRenameTabAction, WriteAction, WriteCharsAction, WriteCharsToPaneIdAction,
+            WriteToPaneIdAction,
         };
         use std::collections::HashMap;
 
@@ -834,6 +835,12 @@ impl From<crate::input::actions::Action>
                     chars,
                 })
             },
+            crate::input::actions::Action::Paste { chars, pane_id } => {
+                ActionType::Paste(PasteAction {
+                    chars,
+                    pane_id: pane_id.map(|p| p.into()),
+                })
+            },
             crate::input::actions::Action::SwitchToMode { input_mode } => {
                 ActionType::SwitchToMode(SwitchToModeAction {
                     input_mode: input_mode_to_proto_i32(input_mode),
@@ -1513,6 +1520,10 @@ impl TryFrom<crate::client_server_contract::client_server_contract::Action>
                         .try_into()?,
                 })
             },
+            ActionType::Paste(paste_action) => Ok(crate::input::actions::Action::Paste {
+                chars: paste_action.chars,
+                pane_id: paste_action.pane_id.map(|p| p.try_into()).transpose()?,
+            }),
             ActionType::SwitchToMode(switch_mode_action) => {
                 Ok(crate::input::actions::Action::SwitchToMode {
                     input_mode: proto_i32_to_input_mode(switch_mode_action.input_mode)?,
diff --git a/zellij-utils/src/plugin_api/action.rs b/zellij-utils/src/plugin_api/action.rs
index 81db2c67..b115b86d 100644
--- a/zellij-utils/src/plugin_api/action.rs
+++ b/zellij-utils/src/plugin_api/action.rs
@@ -1056,10 +1056,11 @@ impl TryFrom<Action> for ProtobufAction {
             }),
             Action::WriteToPaneId { .. }
             | Action::WriteCharsToPaneId { .. }
+            | Action::Paste { .. }
             | Action::GoToTabById { .. }
             | Action::CloseTabById { .. }
             | Action::RenameTabById { .. } => {
-                Err("WriteToPaneId, WriteCharsToPaneId, GoToTabById, CloseTabById, and RenameTabById are CLI-only actions, not available in keybindings")
+                Err("WriteToPaneId, WriteCharsToPaneId, Paste, GoToTabById, CloseTabById, and RenameTabById are CLI-only actions, not available in keybindings")
             },
             Action::SwitchToMode { input_mode } => {
                 let input_mode: ProtobufInputMode = input_mode.try_into()?;