feat: import Chinese-localized Buzz source snapshot

Signed-off-by: cls_宁波本机 <908705107@qq.com>
2026-08-13 18:34:25 +08:00
parent 61c3fa1df9
commit 9dfa06ffee
3785 changed files with 1085458 additions and 2 deletions
@@ -0,0 +1,80 @@
+import 'dart:async';
+import 'dart:math';
+
+/// Creates a timer used by [RelayRateLimitGate].
+typedef RelayTimerFactory =
+    Timer Function(Duration duration, void Function() callback);
+
+/// Session-owned gate that pauses relay requests after back-pressure.
+class RelayRateLimitGate {
+  /// Default gate duration when the relay omits a positive retry hint.
+  static const defaultRetrySeconds = 10;
+
+  /// Longest retry hint accepted from a relay response.
+  static const maxRetrySeconds = 300;
+
+  RelayRateLimitGate({
+    DateTime Function()? now,
+    RelayTimerFactory timerFactory = Timer.new,
+  }) : _now = now ?? DateTime.now,
+       _timerFactory = timerFactory;
+
+  final DateTime Function() _now;
+  final RelayTimerFactory _timerFactory;
+  DateTime? _expiresAt;
+  Timer? _timer;
+  Completer<void>? _completer;
+
+  /// Whether a rate-limit window is currently active.
+  bool get isActive {
+    final expiresAt = _expiresAt;
+    return expiresAt != null && _now().isBefore(expiresAt);
+  }
+
+  /// Activates or extends the gate without shrinking an existing window.
+  void activate(int? retryInSeconds) {
+    final seconds = retryInSeconds != null && retryInSeconds > 0
+        ? min(retryInSeconds, maxRetrySeconds)
+        : defaultRetrySeconds;
+    final duration = Duration(seconds: seconds);
+    final newExpiry = _now().add(duration);
+    final currentExpiry = _expiresAt;
+    if (currentExpiry != null && !newExpiry.isAfter(currentExpiry)) return;
+
+    _expiresAt = newExpiry;
+    _timer?.cancel();
+    _completer ??= Completer<void>();
+    _timer = _timerFactory(duration, _expire);
+  }
+
+  /// Resolves when the active rate-limit window expires.
+  Future<void> wait() {
+    if (!isActive) return Future.value();
+    return _completer!.future;
+  }
+
+  /// Milliseconds remaining in the active window, or zero when inactive.
+  int remainingMs() {
+    final expiresAt = _expiresAt;
+    if (expiresAt == null) return 0;
+    return max(0, expiresAt.difference(_now()).inMilliseconds);
+  }
+
+  /// Clears the gate and releases all current waiters.
+  void reset() {
+    _timer?.cancel();
+    _timer = null;
+    _expiresAt = null;
+    final completer = _completer;
+    _completer = null;
+    if (completer != null && !completer.isCompleted) completer.complete();
+  }
+
+  void _expire() {
+    _timer = null;
+    _expiresAt = null;
+    final completer = _completer;
+    _completer = null;
+    if (completer != null && !completer.isCompleted) completer.complete();
+  }
+}