import axios from 'axios';
import type { AxiosInstance, InternalAxiosRequestConfig, AxiosResponse } from 'axios';

const API_BASE_URL = '/api';

class ApiClient {
  private client: AxiosInstance;

  constructor() {
    this.client = axios.create({
      baseURL: API_BASE_URL,
      headers: {
        'Content-Type': 'application/json',
      },
    });

    // Request interceptor to add auth token
    this.client.interceptors.request.use(
      (config: InternalAxiosRequestConfig) => {
        const token = localStorage.getItem('auth_token');
        if (token && config.headers) {
          config.headers.Authorization = `Bearer ${token}`;
        }
        return config;
      },
      (error) => Promise.reject(error)
    );

    // Response interceptor for error handling
    this.client.interceptors.response.use(
      (response: AxiosResponse) => response,
      (error) => {
        if (error.response?.status === 401) {
          localStorage.removeItem('auth_token');
          window.location.href = '/login';
        }
        return Promise.reject(error);
      }
    );
  }

  getClient() {
    return this.client;
  }
}

export const apiClient = new ApiClient().getClient();