import 'dart:convert';
import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;
import 'package:just_audio/just_audio.dart';
import 'package:path_provider/path_provider.dart';
import 'package:mymuseum_visitapp/PlatformChannels/audio_routing_channel.dart';
import 'package:mymuseum_visitapp/Services/Glasses/engines/tts_engine.dart';

/// TTS via ElevenLabs API — voix naturelle, payant.
/// Upgrade par rapport à FlutterTtsEngine quand la qualité vocale prime.
class ElevenLabsTtsEngine implements TtsEngine {
  static const String _baseUrl = 'https://api.elevenlabs.io/v1';

  final String apiKey;
  final String voiceId;
  final AudioPlayer _player = AudioPlayer();

  bool _speaking = false;
  String? _lastTempPath;

  ElevenLabsTtsEngine({required this.apiKey, required this.voiceId});

  @override
  bool get isSpeaking => _speaking;

  @override
  Future<void> speak(String text, {String languageCode = 'fr-FR'}) async {
    if (text.isEmpty) return;
    try {
      _speaking = true;
      if (!Platform.isWindows) await AudioRoutingChannel.enableBluetoothOutput();
      await _speakElevenLabs(text);
    } catch (e) {
      debugPrint('[ElevenLabsTtsEngine] speak error: $e');
    } finally {
      _speaking = false;
    }
  }

  @override
  Future<void> stop() async {
    await _player.stop();
    _speaking = false;
  }

  @override
  Future<void> replay() async {
    if (_lastTempPath == null) return;
    await _player.seek(Duration.zero);
    await _player.play();
  }

  Future<void> _speakElevenLabs(String text) async {
    final response = await http.post(
      Uri.parse('$_baseUrl/text-to-speech/$voiceId'),
      headers: {
        'xi-api-key': apiKey,
        'Content-Type': 'application/json',
        'Accept': 'audio/mpeg',
      },
      body: jsonEncode({
        'text': text,
        'model_id': 'eleven_multilingual_v2',
        'voice_settings': {'stability': 0.5, 'similarity_boost': 0.75},
      }),
    );
    if (response.statusCode != 200) {
      throw Exception('ElevenLabs ${response.statusCode}');
    }
    final dir = await getTemporaryDirectory();
    final file = File('${dir.path}/glasses_tts.mp3');
    await file.writeAsBytes(response.bodyBytes, flush: true);
    _lastTempPath = file.path;
    await _player.setFilePath(file.path);
    await _player.play();
  }

  void dispose() => _player.dispose();
}