import axios from 'axios'
import { jwtDecode } from 'jwt-decode'

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

// Function to check if the token has expired
function isTokenExpired(token) {
  // Ensure token is a non-empty string
  if (!token || typeof token !== 'string') {
    console.error('Invalid token: must be a non-empty string')
    return true // Treat it as expired
  }

  try {
    const decodedToken = jwtDecode(token)
    console.log('this is decoded token', decodedToken)
    const now = Math.floor(Date.now() / 1000)
    // Buffer as 5 minu = 300 seconds
    return decodedToken.exp - 300 < now
  } catch (error) {
    console.error('Error decoding token:', error)
    return true // Treat it as expired if decoding fails
  }
}

// Interceptor for handling token expiration and refreshing
backendAxios.interceptors.request.use(
  async (config) => {
    let accessToken = localStorage.getItem('access_token')
    let refreshToken = localStorage.getItem('refresh_token')
    // Fix: handle the case where localStorage returns 'null' as a string
    if (accessToken === 'null') accessToken = null
    if (refreshToken === 'null') refreshToken = null

    // Check if the access token is expired
    if (accessToken == null || refreshToken == null) {
      return config
    }
    if (isTokenExpired(accessToken)) {
      try {
        // If access token is expired, refresh it using the refresh token
        const response = await axios.post(
          '/api/user/signin/refresh-token',
          {},
          {
            headers: {
              Authorization: `Bearer ${refreshToken}`,
              'Content-Type': 'application/json'
            }
          }
        )
        accessToken = response.data.access_token
        refreshToken = response.data.refresh_token

        // Save the new access token to localStorage
        localStorage.setItem('access_token', accessToken)
        localStorage.setItem('refresh_token', refreshToken)
      } catch (error) {
        console.error('Token refresh failed. Redirecting to login.')
        // Optionally, handle token refresh failure (e.g., redirect to login)
        window.location.href = '/front-door'
        return Promise.reject(error)
      }
    }

    // Add the (new) access token to the request headers
    if (accessToken) {
      config.headers.Authorization = `Bearer ${accessToken}`
    }
    return config
  },
  (error) => {
    return Promise.reject(error)
  }
)

export { backendAxios }