Initial commit

2026-07-14 11:11:36 +08:00
commit 656499cf94
604 changed files with 119518 additions and 0 deletions
@@ -0,0 +1,103 @@
+import 'dart:async';
+
+import 'package:flutter/foundation.dart';
+
+
+class NetworkSpeedMonitor {
+  NetworkSpeedMonitor({required this._totalRxBytes, DateTime Function()? now})
+    : _now = now ?? DateTime.now;
+
+  final Future<int?> Function() _totalRxBytes;
+  final DateTime Function() _now;
+  final ValueNotifier<double> speed = ValueNotifier<double>(0);
+  final ValueNotifier<bool> available = ValueNotifier<bool>(false);
+
+  Timer? _timer;
+  int _lastBytes = 0;
+  int? _latestTotalBytes;
+  int? get latestTotalBytes => _latestTotalBytes;
+  DateTime? _lastSampleAt;
+  int _sampleSessionId = 0;
+  bool _disposed = false;
+  bool _sampleInFlight = false;
+
+
+  void start() {
+    if (_disposed) return;
+    _stopActiveSampling(resetValue: true);
+    final sessionId = _sampleSessionId;
+    _timer = Timer.periodic(const Duration(seconds: 1), (_) {
+      if (_disposed || sessionId != _sampleSessionId || _sampleInFlight) {
+        return;
+      }
+      _sampleInFlight = true;
+      unawaited(_sample(sessionId));
+    });
+  }
+
+  void stop() {
+    _stopActiveSampling(resetValue: true);
+  }
+
+  Future<void> _sample(int sessionId) async {
+    try {
+      final totalBytes = await _totalRxBytes();
+      if (_disposed || sessionId != _sampleSessionId) return;
+      if (totalBytes == null) {
+        available.value = false;
+        speed.value = 0.0;
+        return;
+      }
+      available.value = true;
+      final sampled = _sampleSpeedFromTotalBytes(totalBytes);
+      if (sampled != null) {
+        speed.value = sampled;
+      }
+    } finally {
+      if (!_disposed && sessionId == _sampleSessionId) {
+        _sampleInFlight = false;
+      }
+    }
+  }
+
+
+  double? _sampleSpeedFromTotalBytes(int totalBytes) {
+    final now = _now();
+    final lastSampleAt = _lastSampleAt;
+    final lastBytes = _lastBytes;
+
+    _lastBytes = totalBytes;
+    _latestTotalBytes = totalBytes;
+    _lastSampleAt = now;
+
+    if (lastSampleAt == null) return null;
+    if (totalBytes < lastBytes) return 0.0;
+
+    final elapsedMs = now.difference(lastSampleAt).inMilliseconds;
+    final deltaBytes = totalBytes - lastBytes;
+    if (elapsedMs <= 0 || deltaBytes <= 0) return 0.0;
+    return deltaBytes * 1000.0 / elapsedMs;
+  }
+
+  void _stopActiveSampling({required bool resetValue}) {
+    _timer?.cancel();
+    _timer = null;
+    _sampleSessionId++;
+    _sampleInFlight = false;
+    _lastBytes = 0;
+    _latestTotalBytes = null;
+    _lastSampleAt = null;
+    if (resetValue && !_disposed) {
+      available.value = false;
+      speed.value = 0;
+    }
+  }
+
+  void dispose() {
+    if (_disposed) return;
+    _stopActiveSampling(resetValue: false);
+    _disposed = true;
+    speed.dispose();
+    available.dispose();
+  }
+}