import 'http_client.dart';
import 'http_util.dart';
import 'models.dart';
import 'providers/base_provider.dart';

/// Port of g4f `IterListProvider`: try each provider until one returns content.
class IterListProvider {
  IterListProvider(this.providers);

  final List<BaseProvider> providers;

  Future<String> create({
    required List<Message> messages,
    String? model,
  }) async {
    final exceptions = <String, Object>{};
    final ordered = [
      ...providers.where((p) => p.working && !p.isWebView),
      ...providers.where((p) => p.working && p.isWebView),
    ];

    for (final provider in ordered) {
      final alias = provider.resolveModel(model);
      try {
        await warmupOrigin(provider.url);
        final result = await provider.complete(alias, messages);
        if (looksLikeModelOutput(result)) {
          return result.trim();
        }
        exceptions[provider.name] = 'unusable text (${result.trim().length} chars)';
      } catch (e) {
        exceptions[provider.name] = e;
        print('Provider ${provider.name} failed: $e');
      }
    }

    if (exceptions.isEmpty) {
      throw Exception('No G4F providers available.');
    }
    if (exceptions.length == 1) {
      throw Exception('${exceptions.keys.first}: ${exceptions.values.first}');
    }
    throw Exception(
      'RetryProvider failed:\n${exceptions.entries.map((e) => '${e.key}: ${e.value}').join('\n')}',
    );
  }
}