Tricoder/frontend/lib/features/capture/presentation/pages/capture_page.dart

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:path_provider/path_provider.dart';
import 'package:record/record.dart';

import '../../../../services/analysis_providers.dart';
import '../../../shared/presentation/widgets/lab_section_scaffold.dart';

class CapturePage extends ConsumerStatefulWidget {
  const CapturePage({super.key});

  @override
  ConsumerState<CapturePage> createState() => _CapturePageState();
}

class _CapturePageState extends ConsumerState<CapturePage> {
  final AudioRecorder _recorder = AudioRecorder();
  final Stopwatch _stopwatch = Stopwatch();

  Timer? _ticker;
  bool _busy = false;
  bool _isRecording = false;
  Duration _elapsed = Duration.zero;
  String? _lastRecordingPath;
  String? _statusMessage;

  @override
  void dispose() {
    _ticker?.cancel();
    _stopwatch.stop();
    _recorder.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return LabSectionScaffold(
      eyebrow: 'Capture',
      title: 'Create a new observation.',
      description:
          'Record audio on device, persist the file locally, then create an observation and analysis session from the captured metadata.',
      children: [
        Card(
          child: Padding(
            padding: const EdgeInsets.all(20),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text('Recorder Status', style: theme.textTheme.titleLarge),
                const SizedBox(height: 8),
                Text(
                  _statusMessage ??
                      'Ready to capture a short audio observation at 16 kHz mono.',
                  style: theme.textTheme.bodyMedium,
                ),
                const SizedBox(height: 16),
                Text(
                  _formatDuration(_elapsed),
                  style: theme.textTheme.displaySmall,
                ),
                const SizedBox(height: 16),
                Row(
                  children: [
                    Expanded(
                      child: FilledButton(
                        onPressed: (_busy || _isRecording)
                            ? null
                            : _startRecording,
                        child: const Text('Start Recording'),
                      ),
                    ),
                    const SizedBox(width: 12),
                    Expanded(
                      child: OutlinedButton(
                        onPressed: (_busy || !_isRecording)
                            ? null
                            : _stopRecording,
                        child: Text(_busy ? 'Working...' : 'Stop Recording'),
                      ),
                    ),
                  ],
                ),
                if (_lastRecordingPath != null) ...[
                  const SizedBox(height: 18),
                  Text(
                    'Last file: $_lastRecordingPath',
                    style: theme.textTheme.bodyMedium,
                  ),
                ],
              ],
            ),
          ),
        ),
      ],
    );
  }

  Future<void> _startRecording() async {
    setState(() {
      _busy = true;
      _statusMessage = 'Checking microphone permission...';
    });

    try {
      final hasPermission = await _recorder.hasPermission();
      if (!hasPermission) {
        setState(() {
          _statusMessage = 'Microphone permission was denied.';
          _busy = false;
        });
        return;
      }

      final directory = await getTemporaryDirectory();
      final filePath =
          '${directory.path}/tc_capture_${DateTime.now().millisecondsSinceEpoch}.wav';

      await _recorder.start(
        const RecordConfig(
          encoder: AudioEncoder.wav,
          sampleRate: 16000,
          numChannels: 1,
        ),
        path: filePath,
      );

      _stopwatch
        ..reset()
        ..start();
      _ticker?.cancel();
      _ticker = Timer.periodic(const Duration(milliseconds: 200), (_) {
        if (!mounted) return;
        setState(() {
          _elapsed = _stopwatch.elapsed;
        });
      });

      setState(() {
        _busy = false;
        _isRecording = true;
        _elapsed = Duration.zero;
        _lastRecordingPath = filePath;
        _statusMessage = 'Recording in progress.';
      });
    } catch (error) {
      setState(() {
        _busy = false;
        _statusMessage = 'Failed to start recording: $error';
      });
    }
  }

  Future<void> _stopRecording() async {
    setState(() {
      _busy = true;
      _statusMessage = 'Stopping recorder and creating analysis session...';
    });

    try {
      final path = await _recorder.stop();
      _ticker?.cancel();
      _stopwatch.stop();

      final durationMs = _stopwatch.elapsedMilliseconds.clamp(
        1,
        60 * 60 * 1000,
      );
      final finalPath = path ?? _lastRecordingPath;
      if (finalPath == null || finalPath.isEmpty) {
        throw Exception('Recorder did not return a valid file path.');
      }

      final session = await ref
          .read(sessionActionsProvider)
          .createUploadedSession(
            filePath: finalPath,
            durationMs: durationMs,
            sampleRate: 16000,
            channels: 1,
            tags: const ['captured', 'mobile-lab'],
            captureMetadata: {
              'source': 'flutter-recorder',
              'client_file_path': finalPath,
              'device': 'mobile-client',
            },
          );

      if (!mounted) return;

      setState(() {
        _busy = false;
        _isRecording = false;
        _elapsed = _stopwatch.elapsed;
        _lastRecordingPath = finalPath;
        _statusMessage = 'Analysis session ${session.sessionId} created.';
      });

      context.goNamed('observation');
    } catch (error) {
      _ticker?.cancel();
      _stopwatch.stop();
      if (!mounted) return;
      setState(() {
        _busy = false;
        _isRecording = false;
        _statusMessage = 'Failed to stop recording: $error';
      });
    }
  }

  String _formatDuration(Duration value) {
    final minutes = value.inMinutes.remainder(60).toString().padLeft(2, '0');
    final seconds = value.inSeconds.remainder(60).toString().padLeft(2, '0');
    final centiseconds = (value.inMilliseconds.remainder(1000) ~/ 10)
        .toString()
        .padLeft(2, '0');
    return '$minutes:$seconds.$centiseconds';
  }
}