feat: Add game activity status (Experimental)

electron/db/database.ts

@@ -26,6 +26,24 @@ let dbBackupPath = '';
 
 // SQLite files start with this 16-byte header string.
 const SQLITE_MAGIC = 'SQLite format 3\0';
+const SAVE_RETRY_DELAYS_MS = [25, 75, 150, 300, 600];
+const RETRYABLE_SAVE_ERROR_CODES = new Set(['EPERM', 'EACCES', 'EBUSY']);
+
+let saveQueue: Promise<void> = Promise.resolve();
+
+function wait(ms: number): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+function isRetryableSaveError(error: unknown): boolean {
+  if (!error || typeof error !== 'object') {
+    return false;
+  }
+
+  const code = (error as NodeJS.ErrnoException).code;
+
+  return typeof code === 'string' && RETRYABLE_SAVE_ERROR_CODES.has(code);
+}
 
 export function getDataSource(): DataSource | undefined {
   return applicationDataSource;
@@ -87,18 +105,47 @@ function safeguardDbFile(): Uint8Array | undefined {
  * then rename it over the real file. rename() is atomic on the same
  * filesystem, so a crash mid-write can never leave a half-written DB.
  */
-async function atomicSave(data: Uint8Array): Promise<void> {
+async function replaceDatabaseFile(tmpPath: string): Promise<void> {
+  for (let attempt = 0; ; attempt++) {
+    try {
+      await fsp.rename(tmpPath, dbFilePath);
+      return;
+    } catch (error) {
+      const delay = SAVE_RETRY_DELAYS_MS[attempt];
+
+      if (!isRetryableSaveError(error) || delay === undefined) {
+        throw error;
+      }
+
+      await wait(delay);
+    }
+  }
+}
+
+async function writeDatabaseSnapshot(snapshot: Buffer): Promise<void> {
   const tmpPath = dbFilePath + '.tmp-' + randomBytes(6).toString('hex');
 
   try {
-    await fsp.writeFile(tmpPath, Buffer.from(data));
-    await fsp.rename(tmpPath, dbFilePath);
+    await fsp.writeFile(tmpPath, snapshot);
+    await replaceDatabaseFile(tmpPath);
   } catch (err) {
     await fsp.unlink(tmpPath).catch(() => {});
     throw err;
   }
 }
 
+async function atomicSave(data: Uint8Array): Promise<void> {
+  const snapshot = Buffer.from(data);
+  const saveTask = saveQueue.then(
+    () => writeDatabaseSnapshot(snapshot),
+    () => writeDatabaseSnapshot(snapshot)
+  );
+
+  saveQueue = saveTask.catch(() => {});
+
+  return saveTask;
+}
+
 export async function initializeDatabase(): Promise<void> {
   const userDataPath = app.getPath('userData');
   const dbDir = path.join(userDataPath, 'metoyou');