fix(overlay): Linux X11/XWayland stacking, stale pause state, multi-copy selector (#101)

src/main/runtime/linux-x11-cursor-point.ts

@@ -0,0 +1,87 @@
+import { execFile } from 'node:child_process';
+import { getLinuxDesktopEnv, isSupportedWaylandCompositor } from '../../shared/mpv-x11-backend';
+import type { PointerPoint } from './linux-overlay-pointer-interaction';
+
+type CommandRunner = (command: string, args: string[]) => Promise<string>;
+
+const XDOTOOL_CURSOR_ARGS = ['getmouselocation', '--shell'] as const;
+const CURSOR_POINT_MAX_AGE_MS = 1000;
+const COMMAND_FAILURE_RETRY_DELAY_MS = 1000;
+
+function execFileUtf8(command: string, args: string[]): Promise<string> {
+  return new Promise((resolve, reject) => {
+    execFile(command, args, { encoding: 'utf-8' }, (error, stdout) => {
+      if (error) {
+        reject(error);
+        return;
+      }
+      resolve(stdout);
+    });
+  });
+}
+
+export function parseXdotoolMouseLocation(raw: string): PointerPoint | null {
+  const xMatch = raw.match(/^X=(-?\d+)$/m);
+  const yMatch = raw.match(/^Y=(-?\d+)$/m);
+  if (!xMatch || !yMatch) return null;
+
+  const x = Number.parseInt(xMatch[1]!, 10);
+  const y = Number.parseInt(yMatch[1]!, 10);
+  if (!Number.isInteger(x) || !Number.isInteger(y)) return null;
+  return { x, y };
+}
+
+export function createLinuxX11CursorPointReader(options?: {
+  env?: NodeJS.ProcessEnv;
+  now?: () => number;
+  platform?: NodeJS.Platform;
+  runCommand?: CommandRunner;
+}) {
+  const env = options?.env ?? process.env;
+  const now = options?.now ?? (() => Date.now());
+  const platform = options?.platform ?? process.platform;
+  const runCommand = options?.runCommand ?? execFileUtf8;
+  let latest: { point: PointerPoint; updatedAtMs: number } | null = null;
+  let inFlight = false;
+  let retryAfterMs = 0;
+
+  function isSupported(): boolean {
+    if (platform !== 'linux' || !env.DISPLAY?.trim()) return false;
+    if (getLinuxDesktopEnv(env).hasWayland && isSupportedWaylandCompositor(env)) return false;
+    return true;
+  }
+
+  function refresh(): void {
+    const nowMs = now();
+    if (!isSupported() || inFlight || nowMs < retryAfterMs) return;
+
+    inFlight = true;
+    void runCommand('xdotool', [...XDOTOOL_CURSOR_ARGS])
+      .then((raw) => {
+        const point = parseXdotoolMouseLocation(raw);
+        if (!point) {
+          retryAfterMs = now() + COMMAND_FAILURE_RETRY_DELAY_MS;
+          return;
+        }
+        latest = { point, updatedAtMs: now() };
+        retryAfterMs = 0;
+      })
+      .catch(() => {
+        retryAfterMs = now() + COMMAND_FAILURE_RETRY_DELAY_MS;
+      })
+      .finally(() => {
+        inFlight = false;
+      });
+  }
+
+  return {
+    getCursorScreenPoint(fallback: PointerPoint): PointerPoint {
+      refresh();
+      if (latest && now() - latest.updatedAtMs <= CURSOR_POINT_MAX_AGE_MS) {
+        return latest.point;
+      }
+      return fallback;
+    },
+    refresh,
+  };
+}