fix: ensure macOS mpv window helper is built and bundled correctly (#93)

scripts/electron-builder-after-pack.cjs

@@ -1,7 +1,24 @@
 const fs = require('node:fs/promises');
+const fsSync = require('node:fs');
 const path = require('node:path');
 
 const LINUX_FFMPEG_LIBRARY = 'libffmpeg.so';
+const MACOS_WINDOW_HELPER = 'get-mpv-window-macos';
+const DEFAULT_MACOS_APP_BUNDLE = 'SubMiner.app';
+
+function resolveMacOSAppBundlePath(context) {
+  if (context.appOutDir.endsWith('.app')) {
+    return context.appOutDir;
+  }
+
+  const productFilename = context.packager?.appInfo?.productFilename;
+  const bundleName =
+    typeof productFilename === 'string' && productFilename.trim()
+      ? `${productFilename.trim()}.app`
+      : DEFAULT_MACOS_APP_BUNDLE;
+
+  return path.join(context.appOutDir, bundleName);
+}
 
 async function stageLinuxAppImageSharedLibrary(
   context,
@@ -35,12 +52,50 @@ async function stageLinuxAppImageSharedLibrary(
   return true;
 }
 
+async function verifyMacOSWindowHelper(
+  context,
+  deps = {
+    access: (filePath, mode) => fs.access(filePath, mode),
+  },
+) {
+  if (context.electronPlatformName !== 'darwin') return false;
+
+  const appBundlePath = resolveMacOSAppBundlePath(context);
+  const helperPath = path.join(
+    appBundlePath,
+    'Contents',
+    'Resources',
+    'scripts',
+    MACOS_WINDOW_HELPER,
+  );
+
+  try {
+    await deps.access(helperPath, fsSync.constants.X_OK);
+  } catch (error) {
+    if (error && typeof error === 'object' && error.code === 'ENOENT') {
+      throw new Error(
+        `macOS packaging requires ${MACOS_WINDOW_HELPER} at ${helperPath}. Run bun run build:assets on macOS with swiftc available before packaging.`,
+      );
+    }
+    if (error && typeof error === 'object' && error.code === 'EACCES') {
+      throw new Error(`macOS window helper is not executable: ${helperPath}`);
+    }
+    throw error;
+  }
+
+  return true;
+}
+
 async function afterPack(context) {
   await stageLinuxAppImageSharedLibrary(context);
+  await verifyMacOSWindowHelper(context);
 }
 
 module.exports = {
   LINUX_FFMPEG_LIBRARY,
+  MACOS_WINDOW_HELPER,
+  resolveMacOSAppBundlePath,
   stageLinuxAppImageSharedLibrary,
+  verifyMacOSWindowHelper,
   default: afterPack,
 };