EM2_ERP/em2rp/lib/services/text_to_speech_service.dart

import 'dart:js_interop';
import 'package:web/web.dart' as web;
import 'package:em2rp/utils/debug_log.dart';

/// Service de synthèse vocale pour lire des textes à haute voix (Web)
class TextToSpeechService {
  static bool _isInitialized = false;
  static bool _voicesLoaded = false;
  static List<web.SpeechSynthesisVoice> _cachedVoices = [];

  /// Initialiser le service TTS
  static Future<void> initialize() async {
    if (_isInitialized) return;

    try {
      _isInitialized = true;

      final synthesis = web.window.speechSynthesis;

      // Essayer de charger les voix immédiatement
      _cachedVoices = synthesis.getVoices().toDart;

      if (_cachedVoices.isNotEmpty) {
        _voicesLoaded = true;
        DebugLog.info('[TextToSpeechService] Service initialized with ${_cachedVoices.length} voices');
        return;
      }

      // Sur certains navigateurs (Firefox notamment), les voix se chargent de manière asynchrone
      DebugLog.info('[TextToSpeechService] Waiting for voices to load asynchronously...');

      // Attendre l'événement voiceschanged (si supporté)
      final voicesLoaded = await _waitForVoices(synthesis);

      if (voicesLoaded) {
        _cachedVoices = synthesis.getVoices().toDart;
        _voicesLoaded = true;
        DebugLog.info('[TextToSpeechService] ✓ Voices loaded asynchronously: ${_cachedVoices.length}');
      } else {
        DebugLog.warning('[TextToSpeechService] ⚠ No voices found after initialization');
      }
    } catch (e) {
      DebugLog.error('[TextToSpeechService] Erreur lors de l\'initialisation', e);
    }
  }

  /// Attendre le chargement des voix (avec timeout)
  static Future<bool> _waitForVoices(web.SpeechSynthesis synthesis) async {
    // Essayer plusieurs fois avec des délais croissants
    for (int attempt = 0; attempt < 5; attempt++) {
      await Future.delayed(Duration(milliseconds: 100 * (attempt + 1)));

      final voices = synthesis.getVoices().toDart;
      if (voices.isNotEmpty) {
        return true;
      }

      DebugLog.info('[TextToSpeechService] Attempt ${attempt + 1}/5: No voices yet');
    }

    return false;
  }

  /// Lire un texte à haute voix
  static Future<void> speak(String text) async {
    if (!_isInitialized) {
      await initialize();
    }

    try {
      final synthesis = web.window.speechSynthesis;

      DebugLog.info('[TextToSpeechService] Speaking requested: "$text"');

      // Arrêter toute lecture en cours
      synthesis.cancel();

      // Attendre un peu pour que le cancel soit effectif
      await Future.delayed(const Duration(milliseconds: 50));

      // Créer une nouvelle utterance
      final utterance = web.SpeechSynthesisUtterance(text);
      utterance.lang = 'fr-FR';
      utterance.rate = 0.7;
      utterance.pitch = 0.7;
      utterance.volume = 1.0;

      // Récupérer les voix (depuis le cache ou re-charger)
      var voices = _cachedVoices;

      // Si le cache est vide, essayer de recharger
      if (voices.isEmpty) {
        DebugLog.info('[TextToSpeechService] Cache empty, reloading voices...');
        voices = synthesis.getVoices().toDart;

        // Sur Firefox/Linux, les voix peuvent ne pas être disponibles immédiatement
        if (voices.isEmpty && !_voicesLoaded) {
          DebugLog.info('[TextToSpeechService] Waiting for voices with multiple attempts...');

          // Essayer plusieurs fois avec des délais
          for (int i = 0; i < 3; i++) {
            await Future.delayed(Duration(milliseconds: 100 * (i + 1)));
            voices = synthesis.getVoices().toDart;

            if (voices.isNotEmpty) {
              DebugLog.info('[TextToSpeechService] ✓ Voices loaded on attempt ${i + 1}');
              break;
            }
          }
        }

        // Mettre à jour le cache
        if (voices.isNotEmpty) {
          _cachedVoices = voices;
          _voicesLoaded = true;
        }
      }

      DebugLog.info('[TextToSpeechService] Available voices: ${voices.length}');

      if (voices.isNotEmpty) {
        web.SpeechSynthesisVoice? selectedVoice;

        // Lister TOUTES les voix françaises pour debug
        final frenchVoices = <web.SpeechSynthesisVoice>[];
        for (final voice in voices) {
          final lang = voice.lang.toLowerCase();
          if (lang.startsWith('fr')) {
            frenchVoices.add(voice);
            DebugLog.info('[TextToSpeechService]   French: ${voice.name} (${voice.lang}) ${voice.localService ? 'LOCAL' : 'REMOTE'}');
          }
        }

        if (frenchVoices.isEmpty) {
          DebugLog.warning('[TextToSpeechService] ⚠ NO French voices found!');
          DebugLog.info('[TextToSpeechService] Available languages:');
          for (final voice in voices.take(5)) {
            DebugLog.info('[TextToSpeechService]   - ${voice.name} (${voice.lang})');
          }
        }

        // Stratégie de sélection: préférer les voix LOCALES (plus fiables sur Linux)
        for (final voice in frenchVoices) {
          if (voice.localService) {
            selectedVoice = voice;
            DebugLog.info('[TextToSpeechService] ✓ Selected LOCAL French voice: ${voice.name}');
            break;
          }
        }

        // Si pas de voix locale, chercher une voix masculine
        if (selectedVoice == null) {
          for (final voice in frenchVoices) {
            final name = voice.name.toLowerCase();
            if (name.contains('male') ||
                name.contains('homme') ||
                name.contains('thomas') ||
                name.contains('paul') ||
                name.contains('bernard')) {
              selectedVoice = voice;
              DebugLog.info('[TextToSpeechService] Selected male voice: ${voice.name}');
              break;
            }
          }
        }

        // Fallback: première voix française
        selectedVoice ??= frenchVoices.isNotEmpty ? frenchVoices.first : null;

        if (selectedVoice != null) {
          utterance.voice = selectedVoice;
          utterance.lang = selectedVoice.lang; // Utiliser la langue de la voix
          DebugLog.info('[TextToSpeechService] Final voice: ${selectedVoice.name} (${selectedVoice.lang})');
        } else {
          DebugLog.warning('[TextToSpeechService] No French voice, using default with lang=fr-FR');
        }
      } else {
        DebugLog.warning('[TextToSpeechService] ⚠ NO voices available at all!');
        DebugLog.warning('[TextToSpeechService] On Linux: install speech-dispatcher and espeak-ng');
      }

      // Ajouter des événements pour le debug
      utterance.onstart = (web.SpeechSynthesisEvent event) {
        DebugLog.info('[TextToSpeechService] ✓ Speech started');
      }.toJS;

      utterance.onend = (web.SpeechSynthesisEvent event) {
        DebugLog.info('[TextToSpeechService] ✓ Speech ended');
      }.toJS;

      utterance.onerror = (web.SpeechSynthesisErrorEvent event) {
        DebugLog.error('[TextToSpeechService] ✗ Speech error: ${event.error}');

        // Messages spécifiques pour aider au diagnostic
        if (event.error == 'synthesis-failed') {
          DebugLog.error('[TextToSpeechService] ⚠ SYNTHESIS FAILED - Common on Linux');
          DebugLog.error('[TextToSpeechService] Possible causes:');
          DebugLog.error('[TextToSpeechService]   1. speech-dispatcher not installed/running');
          DebugLog.error('[TextToSpeechService]   2. espeak or espeak-ng not installed');
          DebugLog.error('[TextToSpeechService]   3. No TTS engine configured');
          DebugLog.error('[TextToSpeechService] Fix: sudo apt-get install speech-dispatcher espeak-ng');
          DebugLog.error('[TextToSpeechService] Then restart browser');
        } else if (event.error == 'network') {
          DebugLog.error('[TextToSpeechService] Network error - online voice unavailable');
        } else if (event.error == 'audio-busy') {
          DebugLog.error('[TextToSpeechService] Audio system is busy');
        }
      }.toJS;

      // Lire le texte
      synthesis.speak(utterance);
      DebugLog.info('[TextToSpeechService] Speech command sent');
    } catch (e) {
      DebugLog.error('[TextToSpeechService] Erreur lors de la lecture', e);
    }
  }

  /// Arrêter la lecture en cours
  static Future<void> stop() async {
    try {
      web.window.speechSynthesis.cancel();
    } catch (e) {
      DebugLog.error('[TextToSpeechService] Erreur lors de l\'arrêt', e);
    }
  }

  /// Vérifier si le service est en train de lire
  static Future<bool> isSpeaking() async {
    try {
      return web.window.speechSynthesis.speaking;
    } catch (e) {
      return false;
    }
  }

  /// Nettoyer les ressources
  static Future<void> dispose() async {
    try {
      web.window.speechSynthesis.cancel();
    } catch (e) {
      DebugLog.error('[TextToSpeechService] Erreur lors du nettoyage', e);
    }
  }
}