feat: Add middle click

README.md

@@ -86,6 +86,7 @@ Released binaries are not codesigned with a Developer ID, so after every upgrade
 | Enter | Double click |
 | `m`   | Triple click |
 | Delete | Right click |
+| Insert | Middle click (macOS is not supported) |
 | Escape | Close overlay |
 | Backspace | Undo last step |
 | Arrow keys | Scroll (up/down/left/right) |
@@ -115,7 +116,7 @@ An alternative grid mode that recursively subdivides. Instead of two-key combos
 
 - Enter bisect mode: press `b` from normal mode, or launch with `--bisect`
 - Each hint key splits the current region into a smaller grid (2x2 by default)
-- Space / Enter / `m` / Delete act (click / double-click / triple-click / right-click) at the center of the current region and exit
+- Space / Enter / `m` / Delete / Insert act (click / double-click / triple-click / right-click / middle-click) at the center of the current region and exit
 - Backspace pops back up one level
 - Subdivision stops automatically once a cell would fall below `min_cell_size` pixels — the region is highlighted and you can act or back out
 - Press `n` to switch back to normal mode
@@ -127,7 +128,7 @@ An alternative mode for direct keyboard-driven cursor movement. Instead of selec
 - Enter free mode: press `v` from normal or bisect mode, or launch with `--free` (starts at mouse position) or `--free-center` (starts at screen center)
 - Move the cursor with `h` / `j` / `k` / `l` (left / down / up / right)
 - Press `=` to increase speed and `-` to decrease it; the current speed is shown in the top-left corner
-- Space / Enter / `m` / Delete act (click / double-click / triple-click / right-click) and exit
+- Space / Enter / `m` / Delete / Insert act (click / double-click / triple-click / right-click / middle-click) and exit
 - Backspace returns to the previous mode; Escape closes the overlay
 - Key repeat is supported: hold a movement key to move continuously
 
@@ -183,6 +184,7 @@ triple_click = "m"
 close = "escape"
 undo = "backspace"
 right_click = "delete"
+middle_click = "insert"
 scroll_up = "up"
 scroll_down = "down"
 scroll_left = "left"

src/backend/macos.rs

@@ -686,6 +686,11 @@ impl Backend for MacosBackend {
         Ok(())
     }
 
+    fn middle_click(&mut self, x: u32, y: u32) -> Result<()> {
+        unimplemented!();
+        Ok(())
+    }
+
     fn drag_select(&mut self, x1: u32, y1: u32, x2: u32, y2: u32) -> Result<()> {
         self.hide_overlay();
         self.focus_target_app();

src/backend/mod.rs

@@ -11,6 +11,7 @@ pub enum KeyEvent {
     DoubleClick,
     TripleClick,
     RightClick,
+    MiddleClick,
     Close,
     Undo,
     MacroMenu,
@@ -50,6 +51,9 @@ pub trait Backend {
     /// Tear down the overlay, right click at (x, y), then return.
     fn right_click(&mut self, x: u32, y: u32) -> Result<()>;
 
+    /// Tear down the overlay, middle click at (x, y), then return.
+    fn middle_click(&mut self, x: u32, y: u32) -> Result<()>;
+
     /// Tear down the overlay, drag from (x1,y1) to (x2,y2), then return.
     fn drag_select(&mut self, x1: u32, y1: u32, x2: u32, y2: u32) -> Result<()>;
 

src/backend/wayland.rs

@@ -25,6 +25,7 @@ use crate::config::{config, Key};
 
 const BTN_LEFT: u32 = 0x110;
 const BTN_RIGHT: u32 = 0x111;
+const BTN_MIDDLE: u32 = 0x112;
 
 const REPEAT_DELAY_MS: u64 = 300;
 const REPEAT_RATE_HZ: u64 = 25;
@@ -291,6 +292,32 @@ impl Backend for WaylandBackend {
         Ok(())
     }
 
+    /// Destroy the overlay so the compositor removes it from the surface stack,
+    /// then re-send motion to trigger a focus update, then middle click.
+    fn middle_click(&mut self, x: u32, y: u32) -> Result<()> {
+        self.teardown_surface()?;
+
+        if let Some(vp) = &self.state.vp {
+            vp.motion_absolute(timestamp(), x, y, self.state.screen_w, self.state.screen_h);
+            vp.frame();
+        }
+        self.eq
+            .roundtrip(&mut self.state)
+            .context("roundtrip after motion")?;
+
+        if let Some(vp) = &self.state.vp {
+            let ts = timestamp();
+            vp.button(ts, BTN_MIDDLE, wl_pointer::ButtonState::Pressed);
+            vp.frame();
+            vp.button(ts, BTN_MIDDLE, wl_pointer::ButtonState::Released);
+            vp.frame();
+        }
+        self.eq
+            .roundtrip(&mut self.state)
+            .context("roundtrip after click")?;
+        Ok(())
+    }
+
     fn scroll_up(&mut self) -> Result<()> {
         self.scroll(Axis::VerticalScroll, -15.0, -1)
     }

src/backend/x11.rs

@@ -13,6 +13,7 @@ use super::{Backend, KeyEvent};
 use crate::config::{config, Key};
 
 const BTN_LEFT: u8 = 1;
+const BTN_MIDDLE: u8 = 2;
 const BTN_RIGHT: u8 = 3;
 const BTN_SCROLL_UP: u8 = 4;
 const BTN_SCROLL_DOWN: u8 = 5;
@@ -254,6 +255,12 @@ impl Backend for X11Backend {
         self.fake_button_click(BTN_RIGHT)
     }
 
+    fn middle_click(&mut self, x: u32, y: u32) -> Result<()> {
+        self.teardown()?;
+        self.warp_and_sync(x, y)?;
+        self.fake_button_click(BTN_MIDDLE)
+    }
+
     fn drag_select(&mut self, x1: u32, y1: u32, x2: u32, y2: u32) -> Result<()> {
         self.teardown()?;
         self.warp_and_sync(x1, y1)?;

src/config.rs

@@ -219,6 +219,7 @@ pub struct KeyBindings {
     pub macro_menu: Key,
     pub macro_record: Key,
     pub right_click: Key,
+    pub middle_click: Key,
     pub scroll_up: Key,
     pub scroll_down: Key,
     pub scroll_left: Key,
@@ -239,6 +240,7 @@ impl Default for KeyBindings {
             macro_menu: Key::Tab,
             macro_record: Key::Char('`'),
             right_click: Key::Delete,
+            middle_click: Key::Insert,
             scroll_up: Key::Up,
             scroll_down: Key::Down,
             scroll_left: Key::Left,
@@ -284,6 +286,9 @@ impl KeyBindings {
         if key == self.right_click {
             return Some(KeyEvent::RightClick);
         }
+        if key == self.middle_click {
+            return Some(KeyEvent::MiddleClick);
+        }
         if key == self.scroll_up {
             return Some(KeyEvent::ScrollUp);
         }

src/macro_store.rs

@@ -9,6 +9,7 @@ pub enum MacroActionKind {
     DoubleClick(String),
     TripleClick(String),
     RightClick(String),
+    MiddleClick(String),
     Drag(String, String),
 }
 

src/mode/bisect.rs

@@ -38,6 +38,10 @@ pub(super) fn handle_key<B: Backend>(
             backend.right_click(cx, cy)?;
             Ok(ModeTransition::Exit)
         }
+        KeyEvent::MiddleClick => {
+            backend.middle_click(cx, cy)?;
+            Ok(ModeTransition::Exit)
+        }
         KeyEvent::ScrollUp => {
             backend.scroll_up()?;
             Ok(ModeTransition::Redraw)

src/mode/free.rs

@@ -33,6 +33,10 @@ pub(super) fn handle_key<B: Backend>(
             backend.right_click(x, y)?;
             Ok(ModeTransition::Exit)
         }
+        KeyEvent::MiddleClick => {
+            backend.middle_click(x, y)?;
+            Ok(ModeTransition::Exit)
+        }
         KeyEvent::ScrollUp => {
             backend.scroll_up()?;
             Ok(ModeTransition::Redraw)

src/mode/mod.rs

@@ -276,6 +276,11 @@ pub(super) fn replay_macro(
                     backend.right_click(x, y)?;
                 }
             }
+            MacroActionKind::MiddleClick(keys) => {
+                if let Some((x, y)) = keys_to_pos(keys, w, h) {
+                    backend.middle_click(x, y)?;
+                }
+            }
             MacroActionKind::Drag(start_keys, end_keys) => {
                 if let (Some((x1, y1)), Some((x2, y2))) =
                     (keys_to_pos(start_keys, w, h), keys_to_pos(end_keys, w, h))

src/mode/normal.rs

@@ -53,6 +53,12 @@ pub(super) fn handle_key<B: Backend>(
             }
             Ok(ModeTransition::Exit)
         }
+        KeyEvent::MiddleClick if drag_origin.is_none() => {
+            if let Some((x, y)) = target {
+                backend.middle_click(x, y)?;
+            }
+            Ok(ModeTransition::Exit)
+        }
         KeyEvent::Char('/')
             if matches!(
                 input_state,

src/mode/recording.rs

@@ -131,7 +131,7 @@ pub(super) fn handle_key<B: Backend>(
                 InputState::Ready { .. } => Ok(ModeTransition::Stay),
             }
         }
-        KeyEvent::Click | KeyEvent::DoubleClick | KeyEvent::TripleClick | KeyEvent::RightClick
+        KeyEvent::Click | KeyEvent::DoubleClick | KeyEvent::TripleClick | KeyEvent::RightClick | KeyEvent::MiddleClick
             if target.is_some() && drag_origin.is_none() =>
         {
             let (x, y) = target.unwrap();
@@ -168,6 +168,13 @@ pub(super) fn handle_key<B: Backend>(
                         wait_ms,
                     ));
                 }
+                KeyEvent::MiddleClick => {
+                    backend.middle_click(x, y)?;
+                    new_actions.push(MacroAction::new(
+                        MacroActionKind::MiddleClick(current_keys),
+                        wait_ms,
+                    ));
+                }
                 _ => {}
             }
             backend.reopen()?;