Restore waveform recording controller

lib/screens/mapflow_shell.dart

@@ -2,13 +2,13 @@ import 'dart:async';
 import 'dart:convert';
 import 'dart:math' as math;
 
-import 'package:cross_file/cross_file.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_svg/flutter_svg.dart';
 import 'package:latlong2/latlong.dart' hide Path;
-import 'package:record/record.dart' as record;
+import 'package:waveform_flutter/waveform_flutter.dart' show Amplitude;
+import 'package:waveform_recorder/waveform_recorder.dart';
 
 import '../api/mapflow_api.dart';
 import '../auth/telegram_login_button.dart';
@@ -711,30 +711,26 @@ class AddExperienceFlow extends ConsumerStatefulWidget {
 class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
   static const _minimumInformationUnits = 16.0;
   static const _nearbyPlaceRadiusMeters = 200;
-  static const _amplitudeInterval = Duration(milliseconds: 140);
-  static const _recordConfig = record.RecordConfig(
-    encoder: record.AudioEncoder.wav,
-    numChannels: 1,
-    sampleRate: 44100,
-    autoGain: true,
-    echoCancel: true,
-    noiseSuppress: true,
-  );
 
   final _api = MapflowApi();
-  final _audioRecorder = record.AudioRecorder();
-  final _recordStopwatch = Stopwatch();
+  final _waveController = WaveformRecorderController(
+    interval: const Duration(milliseconds: 45),
+    config: const RecordConfig(
+      numChannels: 1,
+      sampleRate: 44100,
+      autoGain: true,
+      echoCancel: true,
+      noiseSuppress: true,
+    ),
+  );
 
   Future<List<PlaceRecommendation>>? _nearbyPlacesFuture;
-  StreamSubscription<record.Amplitude>? _amplitudeSub;
-  Timer? _progressTimer;
-  XFile? _recordedFile;
+  StreamSubscription<Amplitude>? _amplitudeSub;
   var _step = 0;
   var _informationUnits = 0.0;
   var _recording = false;
   var _submitting = false;
   var _micAllowed = true;
-  var _heardVoice = false;
   var _noiseDb = -72.0;
   var _voicePeakDb = -34.0;
   var _liveLevel = 0.0;
@@ -748,8 +744,7 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
   @override
   void dispose() {
     _amplitudeSub?.cancel();
-    _progressTimer?.cancel();
-    _audioRecorder.dispose();
+    _waveController.dispose();
     super.dispose();
   }
 
@@ -775,27 +770,14 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
   }
 
   Future<void> _startRecording() async {
-    _recordedFile = null;
-    final path = 'mapflow-${DateTime.now().microsecondsSinceEpoch}.wav';
-    await _audioRecorder.start(_recordConfig, path: path);
+    await _waveController.startRecording();
     await _amplitudeSub?.cancel();
-    _recordStopwatch
-      ..reset()
-      ..start();
     _lastInformationAt = DateTime.now();
-    _amplitudeSub = _audioRecorder
-        .onAmplitudeChanged(_amplitudeInterval)
-        .listen(_handleAmplitude);
-    _progressTimer?.cancel();
-    _progressTimer = Timer.periodic(
-      _amplitudeInterval,
-      (_) => _tickRecordingProgress(),
-    );
+    _amplitudeSub = _waveController.amplitudeStream.listen(_handleAmplitude);
 
     setState(() {
       _micAllowed = true;
       _recording = true;
-      _heardVoice = false;
       _liveLevel = 0;
       _informationUnits = 0;
     });
@@ -804,13 +786,7 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
   Future<void> _stopRecording() async {
     await _amplitudeSub?.cancel();
     _amplitudeSub = null;
-    _progressTimer?.cancel();
-    _progressTimer = null;
-    final path = await _audioRecorder.stop();
-    _recordStopwatch.stop();
-    if (path != null && path.isNotEmpty) {
-      _recordedFile = XFile(path, mimeType: 'audio/wav');
-    }
+    await _waveController.stopRecording();
     _lastInformationAt = null;
     if (!mounted) {
       return;
@@ -821,28 +797,14 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
     });
   }
 
-  void _handleAmplitude(record.Amplitude amplitude) {
+  void _handleAmplitude(Amplitude amplitude) {
     final currentDb = amplitude.current;
+    final now = DateTime.now();
     final level = _normalizeDbLevel(currentDb);
+    final informationDelta = _consumeInformationDelta(level, now);
 
     setState(() {
       _liveLevel = _smoothLevel(_liveLevel, level);
-      _heardVoice = _heardVoice || level > 0.08;
-    });
-  }
-
-  void _tickRecordingProgress() {
-    if (!_recording) {
-      return;
-    }
-
-    final effectiveLevel = _heardVoice ? math.max(_liveLevel, 0.34) : _liveLevel;
-    final informationDelta = _consumeInformationDelta(
-      effectiveLevel,
-      DateTime.now(),
-    );
-
-    setState(() {
       _informationUnits = math.min(
         _minimumInformationUnits,
         _informationUnits + informationDelta,
@@ -850,7 +812,7 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
     });
     ref
         .read(placeControllerProvider.notifier)
-        .setReviewDuration(_recordStopwatch.elapsed);
+        .setReviewDuration(_waveController.timeElapsed);
   }
 
   double _normalizeDbLevel(double currentDb) {
@@ -918,7 +880,7 @@ class _AddExperienceFlowState extends ConsumerState<AddExperienceFlow> {
         onSelect: (place) async {
           setState(() => _submitting = true);
           controller.setReviewPlace(place.name);
-          final file = _recordedFile;
+          final file = _waveController.file;
           if (file == null) {
             throw StateError('Voice recording file is required.');
           }