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

class ApiClient {
  final http.Client _httpClient;
  final SharedPreferences _prefs;
  
  ApiClient(this._prefs) : _httpClient = SecureHttpClient.createSecureClient();
  
  // 获取认证头
  Map<String, String> _getHeaders({bool withAuth = true}) {
    final headers = {
      'Content-Type': 'application/json',
      'Accept': 'application/json',
    };
    
    if (withAuth) {
      final token = _prefs.getString('access_token');
      if (token != null && token.isNotEmpty) {
        headers['Authorization'] = 'Bearer $token';
      }
    }
    
    return headers;
  }
  
  // 通用POST请求
  Future<http.Response> post(
    String url, 
    Map<String, dynamic> body, 
    {bool withAuth = false}
  ) async {
    try {
      final response = await _httpClient.post(
        Uri.parse(url),
        headers: _getHeaders(withAuth: withAuth),
        body: json.encode(body),
      );
      return response;
    } catch (e) {
      throw Exception('网络请求失败: $e');
    }
  }
  
  // 通用GET请求
  Future<http.Response> get(
    String url, 
    {bool withAuth = true}
  ) async {
    try {
      final response = await _httpClient.get(
        Uri.parse(url),
        headers: _getHeaders(withAuth: withAuth),
      );
      return response;
    } catch (e) {
      throw Exception('网络请求失败: $e');
    }
  }
  
  // 通用PUT请求
  Future<http.Response> put(
    String url, 
    Map<String, dynamic> body, 
    {bool withAuth = true}
  ) async {
    try {
      final response = await _httpClient.put(
        Uri.parse(url),
        headers: _getHeaders(withAuth: withAuth),
        body: json.encode(body),
      );
      return response;
    } catch (e) {
      throw Exception('网络请求失败: $e');
    }
  }
  
  // 保存tokens
  Future<void> saveTokens(String accessToken, String? refreshToken) async {
    await _prefs.setString('access_token', accessToken);
    if (refreshToken != null && refreshToken.isNotEmpty) {
      await _prefs.setString('refresh_token', refreshToken);
    }
  }
  
  // 清除所有token
  Future<void> clearTokens() async {
    await _prefs.remove('access_token');
    await _prefs.remove('refresh_token');
  }

  // 获取refresh_token
  String? getRefreshToken() {
    return _prefs.getString('refresh_token');
  }
  
  // 检查是否已登录
  bool isLoggedIn() {
    final token = _prefs.getString('access_token');
    return token != null && token.isNotEmpty;
  }
}