Rewrite X11 backend to drop xcap

Use x11rb directly for screenshot capture and window metadata so the Linux build no longer drags in Wayland build dependencies.

Co-authored-by: Codex <noreply@openai.com>

Cargo.toml

@@ -15,7 +15,6 @@ anyhow = "1"
 dirs = "6"
 libc = "0.2"
 uuid = { version = "1", features = ["v4"] }
-xcap = "0.8"
 image = { version = "0.25", features = ["png"] }
 imageproc = "0.26"
 ab_glyph = "0.2"

src/backend/annotate.rs

@@ -45,11 +45,7 @@ pub fn annotate_screenshot(image: &mut RgbaImage, windows: &[WindowInfo]) {
         if w > 0 && h > 0 {
             draw_hollow_rect_mut(image, Rect::at(x, y).of_size(w, h), color);
             if w > 2 && h > 2 {
-                draw_hollow_rect_mut(
-                    image,
-                    Rect::at(x + 1, y + 1).of_size(w - 2, h - 2),
-                    color,
-                );
+                draw_hollow_rect_mut(image, Rect::at(x + 1, y + 1).of_size(w - 2, h - 2), color);
             }
         }
 
@@ -67,6 +63,14 @@ pub fn annotate_screenshot(image: &mut RgbaImage, windows: &[WindowInfo]) {
         );
 
         // Label text
-        draw_text_mut(image, LABEL_FG, label_x + 3, label_y + 2, scale, &font, &label);
+        draw_text_mut(
+            image,
+            LABEL_FG,
+            label_x + 3,
+            label_y + 2,
+            scale,
+            &font,
+            &label,
+        );
     }
 }

src/backend/mod.rs

@@ -1,8 +1,8 @@
 pub mod annotate;
 pub mod x11;
 
-use anyhow::Result;
 use crate::core::types::Snapshot;
+use anyhow::Result;
 
 #[allow(dead_code)]
 pub trait DesktopBackend: Send {

src/backend/x11.rs

@@ -1,86 +1,240 @@
 use anyhow::{Context, Result};
-use enigo::{
-    Axis, Button, Coordinate, Direction, Enigo, Key, Keyboard, Mouse, Settings,
-};
+use enigo::{Axis, Button, Coordinate, Direction, Enigo, Key, Keyboard, Mouse, Settings};
+use image::RgbaImage;
 use x11rb::connection::Connection;
 use x11rb::protocol::xproto::{
-    ClientMessageEvent, ConfigureWindowAux, ConnectionExt as XprotoConnectionExt,
-    EventMask,
+    Atom, AtomEnum, ClientMessageData, ClientMessageEvent, ConfigureWindowAux,
+    ConnectionExt as XprotoConnectionExt, EventMask, GetPropertyReply, ImageFormat, ImageOrder,
+    Window,
 };
 use x11rb::rust_connection::RustConnection;
 
 use super::annotate::annotate_screenshot;
 use crate::core::types::{Snapshot, WindowInfo};
 
+struct Atoms {
+    client_list_stacking: Atom,
+    active_window: Atom,
+    net_wm_name: Atom,
+    utf8_string: Atom,
+    wm_name: Atom,
+    wm_class: Atom,
+    net_wm_state: Atom,
+    net_wm_state_hidden: Atom,
+}
+
 pub struct X11Backend {
     enigo: Enigo,
     conn: RustConnection,
-    root: u32,
+    root: Window,
+    atoms: Atoms,
 }
 
 impl X11Backend {
     pub fn new() -> Result<Self> {
         let enigo = Enigo::new(&Settings::default())
             .map_err(|e| anyhow::anyhow!("Failed to initialize enigo: {e}"))?;
-        let (conn, screen_num) = x11rb::connect(None)
-            .context("Failed to connect to X11 server")?;
+        let (conn, screen_num) = x11rb::connect(None).context("Failed to connect to X11 server")?;
         let root = conn.setup().roots[screen_num].root;
-        Ok(Self { enigo, conn, root })
-    }
+        let atoms = Atoms::new(&conn)?;
+        Ok(Self {
+            enigo,
+            conn,
+            root,
+            atoms,
+        })
     }
 
-impl super::DesktopBackend for X11Backend {
-    fn snapshot(&mut self, annotate: bool) -> Result<Snapshot> {
-        // Get z-ordered window list via xcap (topmost first internally)
-        let windows = xcap::Window::all().context("Failed to enumerate windows")?;
+    fn stacked_windows(&self) -> Result<Vec<Window>> {
+        let mut windows = self
+            .get_property_u32(
+                self.root,
+                self.atoms.client_list_stacking,
+                AtomEnum::WINDOW.into(),
+                1024,
+            )?
+            .into_iter()
+            .map(|id| id as Window)
+            .collect::<Vec<_>>();
 
-        // Get primary monitor for screenshot
-        let monitors = xcap::Monitor::all().context("Failed to enumerate monitors")?;
-        let monitor = monitors.into_iter().next().context("No monitor found")?;
+        if windows.is_empty() {
+            windows = self
+                .conn
+                .query_tree(self.root)?
+                .reply()
+                .context("Failed to query root window tree")?
+                .children;
+        }
 
-        let mut image = monitor
-            .capture_image()
-            .context("Failed to capture screenshot")?;
+        // EWMH exposes bottom-to-top stacking order. Reverse it so @w1 is the topmost window.
+        windows.reverse();
+        Ok(windows)
+    }
 
-        // Build window info list
+    fn collect_window_infos(&self) -> Result<Vec<WindowInfo>> {
+        let active_window = self.active_window()?;
         let mut window_infos = Vec::new();
         let mut ref_counter = 1usize;
 
-        for win in &windows {
-            // Each xcap method returns XCapResult<T> - skip windows where metadata fails
-            let title = win.title().unwrap_or_default();
-            let app_name = win.app_name().unwrap_or_default();
-
-            // Skip windows with empty titles and app names (desktop, panels, etc.)
+        for window in self.stacked_windows()? {
+            let title = self.window_title(window).unwrap_or_default();
+            let app_name = self.window_app_name(window).unwrap_or_default();
             if title.is_empty() && app_name.is_empty() {
                 continue;
             }
 
-            let xcb_id = win.id().unwrap_or(0);
-            let x = win.x().unwrap_or(0);
-            let y = win.y().unwrap_or(0);
-            let width = win.width().unwrap_or(0);
-            let height = win.height().unwrap_or(0);
-            let focused = win.is_focused().unwrap_or(false);
-            let minimized = win.is_minimized().unwrap_or(false);
-
-            let ref_id = format!("w{ref_counter}");
-            ref_counter += 1;
+            let (x, y, width, height) = match self.window_geometry(window) {
+                Ok(geometry) => geometry,
+                Err(_) => continue,
+            };
 
+            let minimized = self.window_is_minimized(window).unwrap_or(false);
             window_infos.push(WindowInfo {
-                ref_id,
-                xcb_id,
+                ref_id: format!("w{ref_counter}"),
+                xcb_id: window,
                 title,
                 app_name,
                 x,
                 y,
                 width,
                 height,
-                focused,
+                focused: active_window == Some(window),
                 minimized,
             });
+            ref_counter += 1;
         }
 
+        Ok(window_infos)
+    }
+
+    fn capture_root_image(&self) -> Result<RgbaImage> {
+        let (width, height) = self.root_geometry()?;
+        let reply = self
+            .conn
+            .get_image(
+                ImageFormat::Z_PIXMAP,
+                self.root,
+                0,
+                0,
+                width as u16,
+                height as u16,
+                u32::MAX,
+            )?
+            .reply()
+            .context("Failed to capture root window image")?;
+
+        rgba_from_image_reply(self.conn.setup(), width, height, &reply)
+    }
+
+    fn root_geometry(&self) -> Result<(u32, u32)> {
+        let geometry = self
+            .conn
+            .get_geometry(self.root)?
+            .reply()
+            .context("Failed to get root geometry")?;
+        Ok((geometry.width.into(), geometry.height.into()))
+    }
+
+    fn window_geometry(&self, window: Window) -> Result<(i32, i32, u32, u32)> {
+        let geometry = self
+            .conn
+            .get_geometry(window)?
+            .reply()
+            .context("Failed to get window geometry")?;
+        let translated = self
+            .conn
+            .translate_coordinates(window, self.root, 0, 0)?
+            .reply()
+            .context("Failed to translate window coordinates to root")?;
+
+        Ok((
+            i32::from(translated.dst_x),
+            i32::from(translated.dst_y),
+            geometry.width.into(),
+            geometry.height.into(),
+        ))
+    }
+
+    fn active_window(&self) -> Result<Option<Window>> {
+        Ok(self
+            .get_property_u32(
+                self.root,
+                self.atoms.active_window,
+                AtomEnum::WINDOW.into(),
+                1,
+            )?
+            .into_iter()
+            .next()
+            .map(|id| id as Window))
+    }
+
+    fn window_title(&self, window: Window) -> Result<String> {
+        let title =
+            self.read_text_property(window, self.atoms.net_wm_name, self.atoms.utf8_string)?;
+        if !title.is_empty() {
+            return Ok(title);
+        }
+
+        self.read_text_property(window, self.atoms.wm_name, AtomEnum::ANY.into())
+    }
+
+    fn window_app_name(&self, window: Window) -> Result<String> {
+        let wm_class =
+            self.read_text_property(window, self.atoms.wm_class, AtomEnum::STRING.into())?;
+        let mut parts = wm_class.split('\0').filter(|part| !part.is_empty());
+        Ok(parts
+            .nth(1)
+            .or_else(|| parts.next())
+            .unwrap_or("")
+            .to_string())
+    }
+
+    fn window_is_minimized(&self, window: Window) -> Result<bool> {
+        let states =
+            self.get_property_u32(window, self.atoms.net_wm_state, AtomEnum::ATOM.into(), 32)?;
+        Ok(states.contains(&self.atoms.net_wm_state_hidden))
+    }
+
+    fn read_text_property(&self, window: Window, property: Atom, type_: Atom) -> Result<String> {
+        let reply = self.get_property(window, property, type_, 1024)?;
+        Ok(String::from_utf8_lossy(&reply.value)
+            .trim_end_matches('\0')
+            .to_string())
+    }
+
+    fn get_property_u32(
+        &self,
+        window: Window,
+        property: Atom,
+        type_: Atom,
+        long_length: u32,
+    ) -> Result<Vec<u32>> {
+        let reply = self.get_property(window, property, type_, long_length)?;
+        Ok(reply
+            .value32()
+            .map(|iter| iter.collect::<Vec<_>>())
+            .unwrap_or_default())
+    }
+
+    fn get_property(
+        &self,
+        window: Window,
+        property: Atom,
+        type_: Atom,
+        long_length: u32,
+    ) -> Result<GetPropertyReply> {
+        self.conn
+            .get_property(false, window, property, type_, 0, long_length)?
+            .reply()
+            .with_context(|| format!("Failed to read property {property} from window {window}"))
+    }
+}
+
+impl super::DesktopBackend for X11Backend {
+    fn snapshot(&mut self, annotate: bool) -> Result<Snapshot> {
+        let window_infos = self.collect_window_infos()?;
+        let mut image = self.capture_root_image()?;
+
         // Annotate if requested - draw bounding boxes and @wN labels
         if annotate {
             annotate_screenshot(&mut image, &window_infos);
@@ -117,7 +271,7 @@ impl super::DesktopBackend for X11Backend {
             sequence: 0,
             window: xcb_id,
             type_: net_active,
-            data: x11rb::protocol::xproto::ClientMessageData::from([
+            data: ClientMessageData::from([
                 2u32, 0, 0, 0, 0, // source=2 (pager), timestamp=0, currently_active=0
             ]),
         };
@@ -128,21 +282,27 @@ impl super::DesktopBackend for X11Backend {
             EventMask::SUBSTRUCTURE_REDIRECT | EventMask::SUBSTRUCTURE_NOTIFY,
             event,
         )?;
-        self.conn.flush().context("Failed to flush X11 connection")?;
+        self.conn
+            .flush()
+            .context("Failed to flush X11 connection")?;
         Ok(())
     }
 
     fn move_window(&mut self, xcb_id: u32, x: i32, y: i32) -> Result<()> {
         self.conn
             .configure_window(xcb_id, &ConfigureWindowAux::new().x(x).y(y))?;
-        self.conn.flush().context("Failed to flush X11 connection")?;
+        self.conn
+            .flush()
+            .context("Failed to flush X11 connection")?;
         Ok(())
     }
 
     fn resize_window(&mut self, xcb_id: u32, w: u32, h: u32) -> Result<()> {
         self.conn
             .configure_window(xcb_id, &ConfigureWindowAux::new().width(w).height(h))?;
-        self.conn.flush().context("Failed to flush X11 connection")?;
+        self.conn
+            .flush()
+            .context("Failed to flush X11 connection")?;
         Ok(())
     }
 
@@ -161,7 +321,7 @@ impl super::DesktopBackend for X11Backend {
             sequence: 0,
             window: xcb_id,
             type_: net_close,
-            data: x11rb::protocol::xproto::ClientMessageData::from([
+            data: ClientMessageData::from([
                 0u32, 2, 0, 0, 0, // timestamp=0, source=2 (pager)
             ]),
         };
@@ -172,7 +332,9 @@ impl super::DesktopBackend for X11Backend {
             EventMask::SUBSTRUCTURE_REDIRECT | EventMask::SUBSTRUCTURE_NOTIFY,
             event,
         )?;
-        self.conn.flush().context("Failed to flush X11 connection")?;
+        self.conn
+            .flush()
+            .context("Failed to flush X11 connection")?;
         Ok(())
     }
 
@@ -289,11 +451,7 @@ impl super::DesktopBackend for X11Backend {
     }
 
     fn screen_size(&self) -> Result<(u32, u32)> {
-        let monitors = xcap::Monitor::all().context("Failed to enumerate monitors")?;
-        let monitor = monitors.into_iter().next().context("No monitor found")?;
-        let w = monitor.width().context("Failed to get monitor width")?;
-        let h = monitor.height().context("Failed to get monitor height")?;
-        Ok((w, h))
+        self.root_geometry()
     }
 
     fn mouse_position(&self) -> Result<(i32, i32)> {
@@ -306,37 +464,10 @@ impl super::DesktopBackend for X11Backend {
     }
 
     fn screenshot(&mut self, path: &str, annotate: bool) -> Result<String> {
-        let monitors = xcap::Monitor::all().context("Failed to enumerate monitors")?;
-        let monitor = monitors.into_iter().next().context("No monitor found")?;
-
-        let mut image = monitor
-            .capture_image()
-            .context("Failed to capture screenshot")?;
+        let mut image = self.capture_root_image()?;
 
         if annotate {
-            let windows = xcap::Window::all().unwrap_or_default();
-            let mut window_infos = Vec::new();
-            let mut ref_counter = 1usize;
-            for win in &windows {
-                let title = win.title().unwrap_or_default();
-                let app_name = win.app_name().unwrap_or_default();
-                if title.is_empty() && app_name.is_empty() {
-                    continue;
-                }
-                window_infos.push(crate::core::types::WindowInfo {
-                    ref_id: format!("w{ref_counter}"),
-                    xcb_id: win.id().unwrap_or(0),
-                    title,
-                    app_name,
-                    x: win.x().unwrap_or(0),
-                    y: win.y().unwrap_or(0),
-                    width: win.width().unwrap_or(0),
-                    height: win.height().unwrap_or(0),
-                    focused: win.is_focused().unwrap_or(false),
-                    minimized: win.is_minimized().unwrap_or(false),
-                });
-                ref_counter += 1;
-            }
+            let window_infos = self.collect_window_infos()?;
             annotate_screenshot(&mut image, &window_infos);
         }
 
@@ -404,3 +535,121 @@ fn parse_key(name: &str) -> Result<Key> {
         other => anyhow::bail!("Unknown key: {other}"),
     }
 }
+
+impl Atoms {
+    fn new(conn: &RustConnection) -> Result<Self> {
+        Ok(Self {
+            client_list_stacking: intern_atom(conn, b"_NET_CLIENT_LIST_STACKING")?,
+            active_window: intern_atom(conn, b"_NET_ACTIVE_WINDOW")?,
+            net_wm_name: intern_atom(conn, b"_NET_WM_NAME")?,
+            utf8_string: intern_atom(conn, b"UTF8_STRING")?,
+            wm_name: intern_atom(conn, b"WM_NAME")?,
+            wm_class: intern_atom(conn, b"WM_CLASS")?,
+            net_wm_state: intern_atom(conn, b"_NET_WM_STATE")?,
+            net_wm_state_hidden: intern_atom(conn, b"_NET_WM_STATE_HIDDEN")?,
+        })
+    }
+}
+
+fn intern_atom(conn: &RustConnection, name: &[u8]) -> Result<Atom> {
+    conn.intern_atom(false, name)?
+        .reply()
+        .with_context(|| format!("Failed to intern atom {}", String::from_utf8_lossy(name)))
+        .map(|reply| reply.atom)
+}
+
+fn rgba_from_image_reply(
+    setup: &x11rb::protocol::xproto::Setup,
+    width: u32,
+    height: u32,
+    reply: &x11rb::protocol::xproto::GetImageReply,
+) -> Result<RgbaImage> {
+    let pixmap_format = setup
+        .pixmap_formats
+        .iter()
+        .find(|format| format.depth == reply.depth)
+        .context("Failed to find pixmap format for captured image depth")?;
+    let bits_per_pixel = u32::from(pixmap_format.bits_per_pixel);
+    let bit_order = setup.bitmap_format_bit_order;
+    let bytes = reply.data.as_slice();
+
+    let get_pixel_rgba = match reply.depth {
+        8 => pixel8_rgba,
+        16 => pixel16_rgba,
+        24 | 32 => pixel24_32_rgba,
+        depth => anyhow::bail!("Unsupported X11 image depth: {depth}"),
+    };
+
+    let mut rgba = vec![0u8; (width * height * 4) as usize];
+    for y in 0..height {
+        for x in 0..width {
+            let index = ((y * width + x) * 4) as usize;
+            let (r, g, b, a) = get_pixel_rgba(bytes, x, y, width, bits_per_pixel, bit_order);
+            rgba[index] = r;
+            rgba[index + 1] = g;
+            rgba[index + 2] = b;
+            rgba[index + 3] = a;
+        }
+    }
+
+    RgbaImage::from_raw(width, height, rgba)
+        .context("Failed to convert captured X11 image into RGBA buffer")
+}
+
+fn pixel8_rgba(
+    bytes: &[u8],
+    x: u32,
+    y: u32,
+    width: u32,
+    bits_per_pixel: u32,
+    bit_order: ImageOrder,
+) -> (u8, u8, u8, u8) {
+    let index = ((y * width + x) * bits_per_pixel / 8) as usize;
+    let pixel = if bit_order == ImageOrder::LSB_FIRST {
+        bytes[index]
+    } else {
+        bytes[index] & (7 << 4) | (bytes[index] >> 4)
+    };
+
+    let r = (pixel >> 6) as f32 / 3.0 * 255.0;
+    let g = ((pixel >> 2) & 7) as f32 / 7.0 * 255.0;
+    let b = (pixel & 3) as f32 / 3.0 * 255.0;
+    (r as u8, g as u8, b as u8, 255)
+}
+
+fn pixel16_rgba(
+    bytes: &[u8],
+    x: u32,
+    y: u32,
+    width: u32,
+    bits_per_pixel: u32,
+    bit_order: ImageOrder,
+) -> (u8, u8, u8, u8) {
+    let index = ((y * width + x) * bits_per_pixel / 8) as usize;
+    let pixel = if bit_order == ImageOrder::LSB_FIRST {
+        u16::from(bytes[index]) | (u16::from(bytes[index + 1]) << 8)
+    } else {
+        (u16::from(bytes[index]) << 8) | u16::from(bytes[index + 1])
+    };
+
+    let r = (pixel >> 11) as f32 / 31.0 * 255.0;
+    let g = ((pixel >> 5) & 63) as f32 / 63.0 * 255.0;
+    let b = (pixel & 31) as f32 / 31.0 * 255.0;
+    (r as u8, g as u8, b as u8, 255)
+}
+
+fn pixel24_32_rgba(
+    bytes: &[u8],
+    x: u32,
+    y: u32,
+    width: u32,
+    bits_per_pixel: u32,
+    bit_order: ImageOrder,
+) -> (u8, u8, u8, u8) {
+    let index = ((y * width + x) * bits_per_pixel / 8) as usize;
+    if bit_order == ImageOrder::LSB_FIRST {
+        (bytes[index + 2], bytes[index + 1], bytes[index], 255)
+    } else {
+        (bytes[index], bytes[index + 1], bytes[index + 2], 255)
+    }
+}

src/cli/connection.rs

@@ -39,12 +39,10 @@ fn try_connect(opts: &GlobalOpts) -> Option<UnixStream> {
 }
 
 fn spawn_daemon(opts: &GlobalOpts) -> Result<()> {
-    let exe = std::env::current_exe()
-        .context("Failed to determine executable path")?;
+    let exe = std::env::current_exe().context("Failed to determine executable path")?;
 
     let sock_dir = socket_dir();
-    std::fs::create_dir_all(&sock_dir)
-        .context("Failed to create socket directory")?;
+    std::fs::create_dir_all(&sock_dir).context("Failed to create socket directory")?;
 
     let mut cmd = Command::new(exe);
     cmd.env("DESKCTL_DAEMON", "1")
@@ -109,8 +107,8 @@ pub fn send_command(opts: &GlobalOpts, request: &Request) -> Result<Response> {
     let mut line = String::new();
     reader.read_line(&mut line)?;
 
-    let response: Response = serde_json::from_str(line.trim())
-        .context("Failed to parse daemon response")?;
+    let response: Response =
+        serde_json::from_str(line.trim()).context("Failed to parse daemon response")?;
 
     Ok(response)
 }

src/cli/mod.rs

@@ -1,8 +1,8 @@
 mod connection;
 
+use anyhow::Result;
 use clap::{Args, Parser, Subcommand};
 use std::path::PathBuf;
-use anyhow::Result;
 
 use crate::core::protocol::{Request, Response};
 
@@ -196,84 +196,57 @@ fn build_request(cmd: &Command) -> Result<Request> {
     use serde_json::json;
     let req = match cmd {
         Command::Snapshot { annotate } => {
-            Request::new("snapshot")
-                .with_extra("annotate", json!(annotate))
+            Request::new("snapshot").with_extra("annotate", json!(annotate))
         }
         Command::Click { selector } => {
-            Request::new("click")
-                .with_extra("selector", json!(selector))
+            Request::new("click").with_extra("selector", json!(selector))
         }
         Command::Dblclick { selector } => {
-            Request::new("dblclick")
-                .with_extra("selector", json!(selector))
-        }
-        Command::Type { text } => {
-            Request::new("type")
-                .with_extra("text", json!(text))
-        }
-        Command::Press { key } => {
-            Request::new("press")
-                .with_extra("key", json!(key))
-        }
-        Command::Hotkey { keys } => {
-            Request::new("hotkey")
-                .with_extra("keys", json!(keys))
+            Request::new("dblclick").with_extra("selector", json!(selector))
         }
+        Command::Type { text } => Request::new("type").with_extra("text", json!(text)),
+        Command::Press { key } => Request::new("press").with_extra("key", json!(key)),
+        Command::Hotkey { keys } => Request::new("hotkey").with_extra("keys", json!(keys)),
         Command::Mouse(sub) => match sub {
-            MouseCmd::Move { x, y } => {
-                Request::new("mouse-move")
+            MouseCmd::Move { x, y } => Request::new("mouse-move")
                 .with_extra("x", json!(x))
-                    .with_extra("y", json!(y))
-            }
-            MouseCmd::Scroll { amount, axis } => {
-                Request::new("mouse-scroll")
+                .with_extra("y", json!(y)),
+            MouseCmd::Scroll { amount, axis } => Request::new("mouse-scroll")
                 .with_extra("amount", json!(amount))
-                    .with_extra("axis", json!(axis))
-            }
-            MouseCmd::Drag { x1, y1, x2, y2 } => {
-                Request::new("mouse-drag")
+                .with_extra("axis", json!(axis)),
+            MouseCmd::Drag { x1, y1, x2, y2 } => Request::new("mouse-drag")
                 .with_extra("x1", json!(x1))
                 .with_extra("y1", json!(y1))
                 .with_extra("x2", json!(x2))
-                    .with_extra("y2", json!(y2))
-            }
+                .with_extra("y2", json!(y2)),
         },
         Command::Focus { selector } => {
-            Request::new("focus")
-                .with_extra("selector", json!(selector))
+            Request::new("focus").with_extra("selector", json!(selector))
         }
         Command::Close { selector } => {
-            Request::new("close")
-                .with_extra("selector", json!(selector))
+            Request::new("close").with_extra("selector", json!(selector))
         }
-        Command::MoveWindow { selector, x, y } => {
-            Request::new("move-window")
+        Command::MoveWindow { selector, x, y } => Request::new("move-window")
             .with_extra("selector", json!(selector))
             .with_extra("x", json!(x))
-                .with_extra("y", json!(y))
-        }
-        Command::ResizeWindow { selector, w, h } => {
-            Request::new("resize-window")
+            .with_extra("y", json!(y)),
+        Command::ResizeWindow { selector, w, h } => Request::new("resize-window")
             .with_extra("selector", json!(selector))
             .with_extra("w", json!(w))
-                .with_extra("h", json!(h))
-        }
+            .with_extra("h", json!(h)),
         Command::ListWindows => Request::new("list-windows"),
         Command::GetScreenSize => Request::new("get-screen-size"),
         Command::GetMousePosition => Request::new("get-mouse-position"),
         Command::Screenshot { path, annotate } => {
-            let mut req = Request::new("screenshot")
-                .with_extra("annotate", json!(annotate));
+            let mut req = Request::new("screenshot").with_extra("annotate", json!(annotate));
             if let Some(p) = path {
                 req = req.with_extra("path", json!(p.to_string_lossy()));
             }
             req
         }
-        Command::Launch { command, args } => {
-            Request::new("launch")
+        Command::Launch { command, args } => Request::new("launch")
             .with_extra("command", json!(command))
-                .with_extra("args", json!(args))
-        }
+            .with_extra("args", json!(args)),
         Command::Daemon(_) => unreachable!(),
     };
     Ok(req)
@@ -298,18 +271,30 @@ fn print_response(cmd: &Command, response: &Response) -> Result<()> {
                     let ref_id = w.get("ref_id").and_then(|v| v.as_str()).unwrap_or("?");
                     let title = w.get("title").and_then(|v| v.as_str()).unwrap_or("");
                     let focused = w.get("focused").and_then(|v| v.as_bool()).unwrap_or(false);
-                    let minimized = w.get("minimized").and_then(|v| v.as_bool()).unwrap_or(false);
+                    let minimized = w
+                        .get("minimized")
+                        .and_then(|v| v.as_bool())
+                        .unwrap_or(false);
                     let x = w.get("x").and_then(|v| v.as_i64()).unwrap_or(0);
                     let y = w.get("y").and_then(|v| v.as_i64()).unwrap_or(0);
                     let width = w.get("width").and_then(|v| v.as_u64()).unwrap_or(0);
                     let height = w.get("height").and_then(|v| v.as_u64()).unwrap_or(0);
-                    let state = if focused { "focused" } else if minimized { "hidden" } else { "visible" };
+                    let state = if focused {
+                        "focused"
+                    } else if minimized {
+                        "hidden"
+                    } else {
+                        "visible"
+                    };
                     let display_title = if title.len() > 30 {
                         format!("{}...", &title[..27])
                     } else {
                         title.to_string()
                     };
-                    println!("@{:<4} {:<30} ({:<7})  {},{} {}x{}", ref_id, display_title, state, x, y, width, height);
+                    println!(
+                        "@{:<4} {:<30} ({:<7})  {},{} {}x{}",
+                        ref_id, display_title, state, x, y, width, height
+                    );
                 }
             }
         } else {

src/core/protocol.rs

@@ -21,10 +21,14 @@ pub struct Response {
 impl Request {
     pub fn new(action: &str) -> Self {
         Self {
-            id: format!("r{}", std::time::SystemTime::now()
+            id: format!(
+                "r{}",
+                std::time::SystemTime::now()
                     .duration_since(std::time::UNIX_EPOCH)
                     .unwrap_or_default()
-                .as_micros() % 1_000_000),
+                    .as_micros()
+                    % 1_000_000
+            ),
             action: action.to_string(),
             extra: Value::Object(serde_json::Map::new()),
         }
@@ -40,10 +44,18 @@ impl Request {
 
 impl Response {
     pub fn ok(data: Value) -> Self {
-        Self { success: true, data: Some(data), error: None }
+        Self {
+            success: true,
+            data: Some(data),
+            error: None,
+        }
     }
 
     pub fn err(msg: impl Into<String>) -> Self {
-        Self { success: false, data: None, error: Some(msg.into()) }
+        Self {
+            success: false,
+            data: None,
+            error: Some(msg.into()),
+        }
     }
 }

src/core/refs.rs

@@ -1,5 +1,5 @@
-use std::collections::HashMap;
 use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[allow(dead_code)]
@@ -26,7 +26,10 @@ pub struct RefMap {
 #[allow(dead_code)]
 impl RefMap {
     pub fn new() -> Self {
-        Self { map: HashMap::new(), next_ref: 1 }
+        Self {
+            map: HashMap::new(),
+            next_ref: 1,
+        }
     }
 
     pub fn clear(&mut self) {
@@ -57,16 +60,14 @@ impl RefMap {
         // Try substring match on app_class or title (case-insensitive)
         let lower = selector.to_lowercase();
         self.map.values().find(|e| {
-            e.app_class.to_lowercase().contains(&lower)
-                || e.title.to_lowercase().contains(&lower)
+            e.app_class.to_lowercase().contains(&lower) || e.title.to_lowercase().contains(&lower)
         })
     }
 
     /// Resolve a selector to the center coordinates of the window.
     pub fn resolve_to_center(&self, selector: &str) -> Option<(i32, i32)> {
-        self.resolve(selector).map(|e| {
-            (e.x + e.width as i32 / 2, e.y + e.height as i32 / 2)
-        })
+        self.resolve(selector)
+            .map(|e| (e.x + e.width as i32 / 2, e.y + e.height as i32 / 2))
     }
 
     pub fn entries(&self) -> impl Iterator<Item = (&String, &RefEntry)> {

src/daemon/handler.rs

@@ -1,15 +1,12 @@
 use std::sync::Arc;
 use tokio::sync::Mutex;
 
+use super::state::DaemonState;
 use crate::backend::DesktopBackend;
 use crate::core::protocol::{Request, Response};
 use crate::core::refs::RefEntry;
-use super::state::DaemonState;
 
-pub async fn handle_request(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+pub async fn handle_request(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     match request.action.as_str() {
         "snapshot" => handle_snapshot(request, state).await,
         "click" => handle_click(request, state).await,
@@ -33,10 +30,7 @@ pub async fn handle_request(
     }
 }
 
-async fn handle_snapshot(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_snapshot(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let annotate = request
         .extra
         .get("annotate")
@@ -70,10 +64,7 @@ async fn handle_snapshot(
     }
 }
 
-async fn handle_click(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_click(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let selector = match request.extra.get("selector").and_then(|v| v.as_str()) {
         Some(s) => s.to_string(),
         None => return Response::err("Missing 'selector' field"),
@@ -92,19 +83,16 @@ async fn handle_click(
     // Resolve as window ref
     match state.ref_map.resolve_to_center(&selector) {
         Some((x, y)) => match state.backend.click(x, y) {
-            Ok(()) => Response::ok(
-                serde_json::json!({"clicked": {"x": x, "y": y, "ref": selector}}),
-            ),
+            Ok(()) => {
+                Response::ok(serde_json::json!({"clicked": {"x": x, "y": y, "ref": selector}}))
+            }
             Err(e) => Response::err(format!("Click failed: {e}")),
         },
         None => Response::err(format!("Could not resolve selector: {selector}")),
     }
 }
 
-async fn handle_dblclick(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_dblclick(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let selector = match request.extra.get("selector").and_then(|v| v.as_str()) {
         Some(s) => s.to_string(),
         None => return Response::err("Missing 'selector' field"),
@@ -130,10 +118,7 @@ async fn handle_dblclick(
     }
 }
 
-async fn handle_type(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_type(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let text = match request.extra.get("text").and_then(|v| v.as_str()) {
         Some(t) => t.to_string(),
         None => return Response::err("Missing 'text' field"),
@@ -147,10 +132,7 @@ async fn handle_type(
     }
 }
 
-async fn handle_press(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_press(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let key = match request.extra.get("key").and_then(|v| v.as_str()) {
         Some(k) => k.to_string(),
         None => return Response::err("Missing 'key' field"),
@@ -164,10 +146,7 @@ async fn handle_press(
     }
 }
 
-async fn handle_hotkey(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_hotkey(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let keys: Vec<String> = match request.extra.get("keys").and_then(|v| v.as_array()) {
         Some(arr) => arr
             .iter()
@@ -184,10 +163,7 @@ async fn handle_hotkey(
     }
 }
 
-async fn handle_mouse_move(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_mouse_move(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let x = match request.extra.get("x").and_then(|v| v.as_i64()) {
         Some(v) => v as i32,
         None => return Response::err("Missing 'x' field"),
@@ -205,10 +181,7 @@ async fn handle_mouse_move(
     }
 }
 
-async fn handle_mouse_scroll(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_mouse_scroll(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let amount = match request.extra.get("amount").and_then(|v| v.as_i64()) {
         Some(v) => v as i32,
         None => return Response::err("Missing 'amount' field"),
@@ -223,17 +196,12 @@ async fn handle_mouse_scroll(
     let mut state = state.lock().await;
 
     match state.backend.scroll(amount, &axis) {
-        Ok(()) => {
-            Response::ok(serde_json::json!({"scrolled": {"amount": amount, "axis": axis}}))
-        }
+        Ok(()) => Response::ok(serde_json::json!({"scrolled": {"amount": amount, "axis": axis}})),
         Err(e) => Response::err(format!("Scroll failed: {e}")),
     }
 }
 
-async fn handle_mouse_drag(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_mouse_drag(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let x1 = match request.extra.get("x1").and_then(|v| v.as_i64()) {
         Some(v) => v as i32,
         None => return Response::err("Missing 'x1' field"),
@@ -297,10 +265,7 @@ async fn handle_window_action(
     }
 }
 
-async fn handle_move_window(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_move_window(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let selector = match request.extra.get("selector").and_then(|v| v.as_str()) {
         Some(s) => s.to_string(),
         None => return Response::err("Missing 'selector' field"),
@@ -322,16 +287,21 @@ async fn handle_move_window(
     }
 }
 
-async fn handle_resize_window(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_resize_window(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let selector = match request.extra.get("selector").and_then(|v| v.as_str()) {
         Some(s) => s.to_string(),
         None => return Response::err("Missing 'selector' field"),
     };
-    let w = request.extra.get("w").and_then(|v| v.as_u64()).unwrap_or(800) as u32;
-    let h = request.extra.get("h").and_then(|v| v.as_u64()).unwrap_or(600) as u32;
+    let w = request
+        .extra
+        .get("w")
+        .and_then(|v| v.as_u64())
+        .unwrap_or(800) as u32;
+    let h = request
+        .extra
+        .get("h")
+        .and_then(|v| v.as_u64())
+        .unwrap_or(600) as u32;
 
     let mut state = state.lock().await;
     let entry = match state.ref_map.resolve(&selector) {
@@ -347,9 +317,7 @@ async fn handle_resize_window(
     }
 }
 
-async fn handle_list_windows(
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_list_windows(state: &Arc<Mutex<DaemonState>>) -> Response {
     let mut state = state.lock().await;
     // Re-run snapshot without screenshot, just to get current window list
     match state.backend.snapshot(false) {
@@ -392,10 +360,7 @@ async fn handle_get_mouse_position(state: &Arc<Mutex<DaemonState>>) -> Response
     }
 }
 
-async fn handle_screenshot(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_screenshot(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let annotate = request
         .extra
         .get("annotate")
@@ -420,10 +385,7 @@ async fn handle_screenshot(
     }
 }
 
-async fn handle_launch(
-    request: &Request,
-    state: &Arc<Mutex<DaemonState>>,
-) -> Response {
+async fn handle_launch(request: &Request, state: &Arc<Mutex<DaemonState>>) -> Response {
     let command = match request.extra.get("command").and_then(|v| v.as_str()) {
         Some(c) => c.to_string(),
         None => return Response::err("Missing 'command' field"),

src/daemon/mod.rs

@@ -28,9 +28,7 @@ async fn async_run() -> Result<()> {
         .map(PathBuf::from)
         .context("DESKCTL_SOCKET_PATH not set")?;
 
-    let pid_path = std::env::var("DESKCTL_PID_PATH")
-        .map(PathBuf::from)
-        .ok();
+    let pid_path = std::env::var("DESKCTL_PID_PATH").map(PathBuf::from).ok();
 
     // Clean up stale socket
     if socket_path.exists() {
@@ -48,7 +46,7 @@ async fn async_run() -> Result<()> {
     let session = std::env::var("DESKCTL_SESSION").unwrap_or_else(|_| "default".to_string());
     let state = Arc::new(Mutex::new(
         DaemonState::new(session, socket_path.clone())
-            .context("Failed to initialize daemon state")?
+            .context("Failed to initialize daemon state")?,
     ));
 
     let shutdown = Arc::new(tokio::sync::Notify::new());
@@ -111,9 +109,8 @@ async fn handle_connection(
     // exits even if the client has already closed the connection.
     if request.action == "shutdown" {
         shutdown.notify_one();
-        let response = crate::core::protocol::Response::ok(
-            serde_json::json!({"message": "Shutting down"})
-        );
+        let response =
+            crate::core::protocol::Response::ok(serde_json::json!({"message": "Shutting down"}));
         let json = serde_json::to_string(&response)?;
         // Ignore write errors - client may have already closed the connection.
         let _ = writer.write_all(format!("{json}\n").as_bytes()).await;