fix(desktop): honor macOS title-bar double-click preference (#1674)

Signed-off-by: npub13fn4ahfnvaa2qwylvegdgeajqs0mph6v4qsw4jcqnw4mjh3hzh2quuucm5 <8a675edd33677aa0389f6650d467b2041fb0df4ca820eacb009babb95e3715d4@sprout-oss.stage.blox.sqprod.co>
Co-authored-by: npub13fn4ahfnvaa2qwylvegdgeajqs0mph6v4qsw4jcqnw4mjh3hzh2quuucm5 <8a675edd33677aa0389f6650d467b2041fb0df4ca820eacb009babb95e3715d4@sprout-oss.stage.blox.sqprod.co>

desktop/src-tauri/src/lib.rs

@@ -67,6 +67,91 @@ fn perform_sidebar_default_haptic() {
     }
 }
 
+/// Performs the window action matching the macOS "double-click a window's
+/// title bar to" preference (`AppleActionOnDoubleClick`).
+///
+/// macOS values are `Minimize`, `Maximize` (default when unset), `Fill`, or
+/// `None`.
+/// The desktop app uses a web-based title-bar drag region, so the frontend
+/// forwards double-clicks here and suppresses Tauri's injected drag-region
+/// handler, whose default macOS path hardcodes maximize.
+///
+/// For `Fill`, resize to the current monitor work area instead of using
+/// Tauri's maximize path, which maps to macOS zoom for titled, resizable
+/// windows.
+///
+/// On non-macOS platforms this always toggles maximize (the historical
+/// behavior).
+#[tauri::command]
+fn title_bar_double_click(window: tauri::Window) {
+    #[cfg(target_os = "macos")]
+    {
+        let action = {
+            let output = std::process::Command::new("defaults")
+                .args(["read", "-g", "AppleActionOnDoubleClick"])
+                .output();
+            match output {
+                Ok(output) if output.status.success() => {
+                    String::from_utf8_lossy(&output.stdout).trim().to_string()
+                }
+                _ => "Maximize".to_string(),
+            }
+        };
+
+        match action.as_str() {
+            "None" => {}
+            "Minimize" => {
+                let _ = window.minimize();
+            }
+            "Fill" => {
+                fill_window(&window);
+            }
+            // "Maximize" or any unexpected value.
+            _ => {
+                toggle_maximize(&window);
+            }
+        }
+    }
+
+    #[cfg(not(target_os = "macos"))]
+    {
+        toggle_maximize(&window);
+    }
+}
+
+/// Fills the current display work area, excluding system UI like the menu bar
+/// and Dock.
+#[cfg(target_os = "macos")]
+fn fill_window(window: &tauri::Window) {
+    match window.current_monitor() {
+        Ok(Some(monitor)) => {
+            if window.is_maximized().unwrap_or(false) {
+                let _ = window.unmaximize();
+            }
+
+            let work_area = monitor.work_area();
+            let _ = window.set_position(work_area.position);
+            let _ = window.set_size(work_area.size);
+        }
+        _ => {
+            let _ = window.maximize();
+        }
+    }
+}
+
+/// Toggles the window between maximized and its previous size, matching the
+/// historical double-click behavior.
+fn toggle_maximize(window: &tauri::Window) {
+    match window.is_maximized() {
+        Ok(true) => {
+            let _ = window.unmaximize();
+        }
+        _ => {
+            let _ = window.maximize();
+        }
+    }
+}
+
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
     let builder = tauri::Builder::default()
@@ -441,6 +526,7 @@ pub fn run() {
             Ok(())
         })
         .invoke_handler(tauri::generate_handler![
+            title_bar_double_click,
             get_identity,
             get_nsec,
             import_identity,

desktop/src/app/AppShell.helpers.ts

@@ -11,10 +11,65 @@ export type AppView =
   | "projects";
 
 const WINDOW_DRAG_HANDLE_HEIGHT = 44;
+const TAURI_DRAG_REGION_ATTR = "data-tauri-drag-region";
 const WINDOW_DRAG_INTERACTIVE_SELECTOR =
-  'button, a, input, textarea, select, [role="button"], [contenteditable="true"]';
+  'button, a, input, textarea, select, label, summary, [role="button"], [role="link"], [role="menuitem"], [role="tab"], [role="checkbox"], [role="radio"], [role="switch"], [role="option"], [contenteditable="true"], [tabindex]:not([tabindex="-1"])';
+
+const CLICKABLE_TAGS = new Set([
+  "A",
+  "BUTTON",
+  "INPUT",
+  "SELECT",
+  "TEXTAREA",
+  "LABEL",
+  "SUMMARY",
+]);
+const INTERACTIVE_ROLES = new Set([
+  "button",
+  "link",
+  "menuitem",
+  "tab",
+  "checkbox",
+  "radio",
+  "switch",
+  "option",
+]);
+
+function isClickableElement(element: HTMLElement) {
+  return (
+    CLICKABLE_TAGS.has(element.tagName) ||
+    (element.hasAttribute("contenteditable") &&
+      element.getAttribute("contenteditable") !== "false") ||
+    (element.hasAttribute("tabindex") &&
+      element.getAttribute("tabindex") !== "-1") ||
+    INTERACTIVE_ROLES.has(element.getAttribute("role") ?? "")
+  );
+}
+
+function isTauriDragRegionEvent(event: MouseEvent | PointerEvent) {
+  const path = event.composedPath();
+  const directTarget = path[0];
+
+  for (const item of path) {
+    if (!(item instanceof HTMLElement)) continue;
+
+    const attr = item.getAttribute(TAURI_DRAG_REGION_ATTR);
+
+    if (isClickableElement(item) && attr === null) return false;
+    if (attr === null) continue;
+    if (attr === "false") return false;
+    if (attr === "deep") return true;
+    if (attr === "" || attr === "true") return item === directTarget;
+  }
+
+  return false;
+}
 
 export function isWindowDragHandleEvent(event: MouseEvent | PointerEvent) {
+  if (isTauriDragRegionEvent(event)) {
+    return true;
+  }
+
   if (event.clientY > WINDOW_DRAG_HANDLE_HEIGHT) {
     return false;
   }

desktop/src/app/useTauriWindowDrag.ts

@@ -2,6 +2,7 @@ import * as React from "react";
 import { getCurrentWindow } from "@tauri-apps/api/window";
 
 import { isWindowDragHandleEvent } from "@/app/AppShell.helpers";
+import { performTitleBarDoubleClickAction } from "@/shared/lib/titleBarActions";
 
 export function useTauriWindowDrag() {
   React.useEffect(() => {
@@ -17,19 +18,35 @@ export function useTauriWindowDrag() {
       void getCurrentWindow().startDragging();
     }
 
+    function stopTauriDragRegionHandler(event: MouseEvent) {
+      if (event.button !== 0 || !isWindowDragHandleEvent(event)) {
+        return;
+      }
+
+      // Tauri's injected data-tauri-drag-region listener hardcodes maximize on
+      // double-click. Buzz handles drag and double-click itself so macOS title
+      // bar preferences can be respected.
+      event.stopImmediatePropagation();
+    }
+
     function handleDoubleClick(event: MouseEvent) {
       if (event.button !== 0 || !isWindowDragHandleEvent(event)) {
         return;
       }
 
       event.preventDefault();
-      void getCurrentWindow().toggleMaximize();
+      event.stopImmediatePropagation();
+      void performTitleBarDoubleClickAction();
     }
 
     window.addEventListener("pointerdown", handlePointerDown, true);
+    window.addEventListener("mousedown", stopTauriDragRegionHandler, true);
+    window.addEventListener("mouseup", stopTauriDragRegionHandler, true);
     window.addEventListener("dblclick", handleDoubleClick, true);
     return () => {
       window.removeEventListener("pointerdown", handlePointerDown, true);
+      window.removeEventListener("mousedown", stopTauriDragRegionHandler, true);
+      window.removeEventListener("mouseup", stopTauriDragRegionHandler, true);
       window.removeEventListener("dblclick", handleDoubleClick, true);
     };
   }, []);

desktop/src/shared/lib/titleBarActions.ts

@@ -0,0 +1,22 @@
+import { invoke, isTauri } from "@tauri-apps/api/core";
+
+/**
+ * Runs the window action that matches the OS "double-click a window's title
+ * bar to" preference (macOS `AppleActionOnDoubleClick`).
+ *
+ * The app uses a web-based title-bar drag region, so the OS does not act on a
+ * title-bar double-click on its own. The Rust `title_bar_double_click` command
+ * reads the preference and dispatches a single matching action (native
+ * `miniaturize:` for minimize, so the window genies into the Dock).
+ */
+export async function performTitleBarDoubleClickAction(): Promise<void> {
+  if (!isTauri()) {
+    return;
+  }
+
+  try {
+    await invoke("title_bar_double_click");
+  } catch {
+    // No-op on failure; a missed titlebar action is not worth surfacing.
+  }
+}

desktop/src/shared/ui/StartupWindowDragRegion.tsx

@@ -1,9 +1,11 @@
 import { getCurrentWindow } from "@tauri-apps/api/window";
 import * as React from "react";
 
+import { performTitleBarDoubleClickAction } from "@/shared/lib/titleBarActions";
+
 const WINDOW_DRAG_HANDLE_HEIGHT = 44;
 const WINDOW_DRAG_INTERACTIVE_SELECTOR =
-  'button, a, input, textarea, select, [role="button"], [contenteditable="true"]';
+  'button, a, input, textarea, select, label, summary, [role="button"], [role="link"], [role="menuitem"], [role="tab"], [role="checkbox"], [role="radio"], [role="switch"], [role="option"], [contenteditable="true"], [tabindex]:not([tabindex="-1"])';
 
 function isWindowDragHandleEvent(event: MouseEvent | PointerEvent) {
   if (event.clientY > WINDOW_DRAG_HANDLE_HEIGHT) {
@@ -31,19 +33,32 @@ export function StartupWindowDragRegion() {
       void getCurrentWindow().startDragging();
     }
 
+    function stopTauriDragRegionHandler(event: MouseEvent) {
+      if (event.button !== 0 || !isWindowDragHandleEvent(event)) {
+        return;
+      }
+
+      event.stopImmediatePropagation();
+    }
+
     function handleDoubleClick(event: MouseEvent) {
       if (event.button !== 0 || !isWindowDragHandleEvent(event)) {
         return;
       }
 
       event.preventDefault();
-      void getCurrentWindow().toggleMaximize();
+      event.stopImmediatePropagation();
+      void performTitleBarDoubleClickAction();
     }
 
     window.addEventListener("pointerdown", handlePointerDown, true);
+    window.addEventListener("mousedown", stopTauriDragRegionHandler, true);
+    window.addEventListener("mouseup", stopTauriDragRegionHandler, true);
     window.addEventListener("dblclick", handleDoubleClick, true);
     return () => {
       window.removeEventListener("pointerdown", handlePointerDown, true);
+      window.removeEventListener("mousedown", stopTauriDragRegionHandler, true);
+      window.removeEventListener("mouseup", stopTauriDragRegionHandler, true);
       window.removeEventListener("dblclick", handleDoubleClick, true);
     };
   }, []);
@@ -52,7 +67,6 @@ export function StartupWindowDragRegion() {
     <div
       aria-hidden="true"
       className="pointer-events-none fixed inset-x-0 top-0 z-20 h-10 select-none"
-      data-tauri-drag-region
     />
   );
 }