iotDashboard/frontend/src/lib/api-client.ts

import axios from 'axios';

// Use Vite proxy in development, or env variable in production
const API_BASE_URL = import.meta.env.VITE_API_URL || '/api';

export const apiClient = axios.create({
  baseURL: API_BASE_URL,
  headers: {
    'Content-Type': 'application/json',
  },
});

// Add token from localStorage on initialization
const token = localStorage.getItem('access_token');
if (token) {
  apiClient.defaults.headers.common['Authorization'] = `Bearer ${token}`;
}

// Add response interceptor for token refresh on 401
apiClient.interceptors.response.use(
  (response) => response,
  async (error) => {
    const originalRequest = error.config;
    
    // Handle 401 errors with token refresh
    if (error.response?.status === 401 && !originalRequest._retry) {
      originalRequest._retry = true;
      
      try {
        const refreshToken = localStorage.getItem('refresh_token');
        if (!refreshToken) {
          throw new Error('No refresh token');
        }
        
        const response = await axios.post(`${API_BASE_URL}/auth/refresh/`, {
          refresh: refreshToken
        });
        
        const { access } = response.data;
        localStorage.setItem('access_token', access);
        apiClient.defaults.headers.common['Authorization'] = `Bearer ${access}`;
        originalRequest.headers['Authorization'] = `Bearer ${access}`;
        
        return apiClient(originalRequest);
      } catch (refreshError) {
        // Refresh failed - clear tokens and redirect to login
        localStorage.removeItem('access_token');
        localStorage.removeItem('refresh_token');
        window.location.href = '/login';
        return Promise.reject(refreshError);
      }
    }
    
    return Promise.reject(error);
  }
);

export default apiClient;