mymuseum-visitapp/lib/Services/assistantService.dart

import 'dart:async';
import 'package:flutter/foundation.dart';
import 'package:manager_api_new/api.dart';
import 'package:mymuseum_visitapp/Models/visitContext.dart';
import 'package:mymuseum_visitapp/Models/AssistantResponse.dart';

/// Levée quand l'instance a épuisé son quota IA du mois (HTTP 429).
///
/// Distincte d'une panne : le visiteur ne doit pas être invité à réessayer, ça
/// le ferait boucler sur un mur. L'appelant affiche un message neutre, sans
/// jamais mentionner le motif — c'est une affaire entre le client et nous.
class AssistantUnavailableException implements Exception {
  const AssistantUnavailableException();
}

class AssistantService {
  final VisitAppContext visitAppContext;

  /// Nombre maximum de messages conservés dans l'historique envoyé au backend.
  final int maxHistory;

  /// Durée d'inactivité après laquelle l'historique est automatiquement vidé.
  /// null = pas de vidage automatique.
  final Duration? inactivityTimeout;

  final List<AiChatMessage> _history = [];
  Timer? _inactivityTimer;

  AssistantService({
    required this.visitAppContext,
    this.maxHistory = 10,
    this.inactivityTimeout = const Duration(minutes: 5),
  });

  Future<AssistantResponse> chat({
    required String message,
    String? configurationId,
    bool isVoice = false,
    bool isAutoTriggered = false,
  }) => chatWithAppType(
        message: message,
        configurationId: configurationId,
        isVoice: isVoice,
        isAutoTriggered: isAutoTriggered,
      );

  /// [isAutoTriggered] : le tour vient du mode proactif, pas d'une question du visiteur.
  /// Le serveur compte les jetons mais ne le journalise pas dans `VisitorQuestion`.
  Future<AssistantResponse> chatWithAppType({
    required String message,
    String? configurationId,
    AppType appType = AppType.Mobile,
    bool isVoice = false,
    bool isAutoTriggered = false,
  }) async {
    _resetInactivityTimer();

    final request = AiChatRequest(
      message: message,
      instanceId: visitAppContext.instanceId,
      appType: appType,
      configurationId: configurationId,
      language: visitAppContext.language?.toUpperCase() ?? 'FR',
      history: List.from(_history),
      isVoice: isVoice,
      isAutoTriggered: isAutoTriggered,
    );

    final AiChatResponse? response;
    try {
      response = await visitAppContext.clientAPI.aiApi!.aiChat(request);
    } on ApiException catch (e) {
      if (e.code == 429) throw const AssistantUnavailableException();
      rethrow;
    }

    if (response == null) {
      throw Exception('Empty response from assistant');
    }

    debugPrint("AI raw response: reply='${response.reply}' navigation.sectionId='${response.navigation?.sectionId}' navigation.sectionTitle='${response.navigation?.sectionTitle}' navigation.sectionType='${response.navigation?.sectionType}' cards=${response.cards?.length}");

    final result = AssistantResponse(
      reply: response.reply ?? '',
      cards: response.cards
          ?.map((c) => AiCard(
                title: c.title ?? '',
                subtitle: c.subtitle ?? '',
                icon: c.icon,
              ))
          .toList(),
      navigation: response.navigation != null
          ? AssistantNavigationAction(
              sectionId: response.navigation!.sectionId ?? '',
              sectionTitle: response.navigation!.sectionTitle ?? '',
              sectionType: response.navigation!.sectionType ?? '',
              imageUrl: response.navigation!.imageUrl,
            )
          : null,
      expectsReply: response.expectsReply ?? true,
    );

    _history.add(AiChatMessage(role: 'user', content: message));
    _history.add(AiChatMessage(role: 'assistant', content: result.reply));

    // Cap local — inutile de garder plus que maxHistory côté client
    if (_history.length > maxHistory) {
      _history.removeRange(0, _history.length - maxHistory);
    }

    return result;
  }

  void _resetInactivityTimer() {
    if (inactivityTimeout == null) return;
    _inactivityTimer?.cancel();
    _inactivityTimer = Timer(inactivityTimeout!, () {
      debugPrint('[AssistantService] Inactivity timeout — clearing history');
      clearHistory();
    });
  }

  void clearHistory() {
    _history.clear();
    _inactivityTimer?.cancel();
  }

  void dispose() {
    _inactivityTimer?.cancel();
  }
}