Socialmedia_Julien/lib/services/post_creation_service.dart

import 'dart:convert';
import 'package:http/http.dart' as http;

/// Définit un contrat pour tout service capable de générer des idées de posts.
abstract class PostCreationService {
  Future<List<String>> generatePostIdeas({
    required String base64Image,
    required String profession,
    required String tone,
  });
}

/// L'implémentation Ollama de ce service.
class OllamaPostCreationService implements PostCreationService {
  final String _apiUrl = 'http://192.168.20.200:11434/api/generate';
  final String _visionModel = 'llava:7b';

  @override
  Future<List<String>> generatePostIdeas({
    required String base64Image,
    required String profession,
    required String tone,
  }) async {
    final requestPrompt = """
    You are a social media expert.
    Act as a "$profession".
    Analyze the image.
    Generate 3 short and engaging social media post ideas in french with a "$tone" tone.
    Your output MUST be a valid JSON array of strings.

    Example:
    ["", "", ""]
    """;

    final requestBody = {
      'model': _visionModel,
      'prompt': requestPrompt,
      'images': [base64Image],
      'stream': false,
    };

    try {
      print("[OllamaPostCreationService] 🚀 Appel pour générer des idées...");
      final response = await http.post(
        Uri.parse(_apiUrl),
        headers: {'Content-Type': 'application/json'},
        body: jsonEncode(requestBody),
      ).timeout(const Duration(minutes: 3));

      if (response.statusCode == 200) {
        final responseData = jsonDecode(response.body);
        final jsonString = (responseData['response'] as String? ?? '').trim();

        if (jsonString.isEmpty) return [];

        try {
          final ideasList = jsonDecode(jsonString) as List;
          return ideasList.map((idea) => idea.toString()).toList();
        } catch (e) {
          print("[OllamaPostCreationService] ❌ Erreur de parsing JSON. Réponse : $jsonString");
          return [jsonString]; // Retourne la réponse brute comme une seule idée
        }
      } else {
        throw Exception('Erreur Ollama (generatePostIdeas) ${response.statusCode}: ${response.body}');
      }
    } catch (e) {
      print("[OllamaPostCreationService] ❌ Exception : ${e.toString()}");
      rethrow;
    }
  }
}