'use strict'
// Import Catalyst Node SDK
const catalyst = require('zcatalyst-sdk-node')
// Import Express framework
const express = require('express')
const app = express()
// Initialize express middleware
app.use(express())
// Import axios to make HTTP requests to Auth0
const axios = require('axios')
// Header name where Auth0 access token is expected
const auth0TokenHeader = 'zc-customauth'
// Replace with your Auth0 domain (example: https://your-domain.auth0.com)
const auth0Domain = '{replace your Auth0 domain}'
// Endpoint to validate Auth0 token and generate Catalyst custom token
app.get('/getauth', async (req, res) => {
  try {
    // Read Auth0 access token from request header
    const auth0AccessToken = req.headers[auth0TokenHeader]
    // Auth0 user info endpoint
    const auth0Url = auth0Domain + '/userinfo'
    // Proceed only if token is provided
    if (auth0AccessToken !== undefined) {
      const url = auth0Url
      // Attach Authorization header with Bearer token
      const config = {
        headers: {
          Authorization: 'Bearer ' + auth0AccessToken
        }
      }
      // Call Auth0 to fetch user details
      const auth0response = await axios.get(url, config)
      // Initialize Catalyst app using request context
      const catalystApp = catalyst.initialize(req)
      // Generate Catalyst custom web token using Auth0 user details
      const tokenObj = await catalystApp.userManagement().generateCustomToken({
        type: 'web',
        user_details: {
          email_id: auth0response.data.email,
          first_name: auth0response.data.given_name,
          last_name: auth0response.data.family_name
        }
      })
      // Send generated Catalyst token back to client
      res.status(200).send(JSON.stringify(tokenObj))
    } else {
      // If Auth0 token is missing in header
      res.status(401).send({ status: 'failure', message: 'Token not provided in the header' })
    }
  } catch (error) {
    // Log error and return failure response
    console.log(error)
    res.status(error.response.status).send({ status: 'failure', message: 'An unexpected error has occured. Please try again after sometime.' })
  }
})
// Endpoint to fetch the currently authenticated Catalyst user
app.get('/catalystUser', async (req, res) => {
  try {
    // Initialize Catalyst using request context
    const catalystApp = catalyst.initialize(req)
    // Retrieve current logged-in Catalyst user
    const currentUser = await catalystApp.userManagement().getCurrentUser()
    // Send user details as response
    res.status(200).send(JSON.stringify(currentUser))
  } catch (error) {
    // Handle and log any unexpected errors
    console.log(error)
    res.status(500).send({ status: 'failure', message: error })
  }
})
// Export the Express app
module.exports = app