import { API_BASE_URL } from '../utils/constants';

interface ApiResponse<T = any> {
  data: T;
  status: number;
}

class ApiClient {
  private baseURL: string;

  constructor(baseURL: string) {
    this.baseURL = baseURL;
  }

  private getAuthHeaders(): Record<string, string> {
    const token = localStorage.getItem('authToken') || localStorage.getItem('token');
    // console.log('API 调用 token:', token ? token.substring(0, 10) + '...' : 'null');
    return {
      'Content-Type': 'application/json',
      ...(token && { Authorization: `Bearer ${token}` }),
    };
  }

  // 新式的 API 调用方法，返回 { data, status }
  async get<T = any>(url: string): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'GET',
      headers: this.getAuthHeaders(),
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.message || 'Request failed');
    }

    const data = await response.json();
    return { data, status: response.status };
  }

  async post<T = any>(url: string, body?: any): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'POST',
      headers: this.getAuthHeaders(),
      body: body ? JSON.stringify(body) : undefined,
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.message || 'Request failed');
    }

    const data = await response.json();
    return { data, status: response.status };
  }

  async put<T = any>(url: string, body?: any): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'PUT',
      headers: this.getAuthHeaders(),
      body: body ? JSON.stringify(body) : undefined,
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.message || 'Request failed');
    }

    const data = await response.json();
    return { data, status: response.status };
  }

  async delete<T = any>(url: string): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'DELETE',
      headers: this.getAuthHeaders(),
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.message || 'Request failed');
    }

    const data = await response.json();
    return { data, status: response.status };
  }

  // 保持原有的 API 兼容性方法，接受路径和选项参数并返回原始 Response
  async request(path: string, options: RequestInit = {}): Promise<Response> {
    const token = localStorage.getItem('authToken');
    const headers = new Headers(options.headers);

    if (token) {
        headers.set('Authorization', `Bearer ${token}`);
    }

    // 构建完整 URL
    let url = path;
    if (!path.startsWith('http')) {
        const cleanPath = path.startsWith('/') ? path : `/${path}`;
        url = `${this.baseURL}${cleanPath}`;
    }

    const response = await fetch(url, {
        ...options,
        headers,
    });

    if (response.status === 401) {
        localStorage.removeItem('authToken');
        window.location.reload();
        throw new Error('Unauthorized');
    }

    return response;
  }
}

export const apiClient = new ApiClient(API_BASE_URL);