const chokidar = require('chokidar')
const bodyParser = require('body-parser')
const chalk = require('chalk')
const path = require('path')
const Mock = require('mockjs')
const router = require('express').Router()

const mockDir = path.join(process.cwd(), 'mock')

function unregisterRoutes () {
  Object.keys(require.cache).forEach(i => {
    if (i.includes(mockDir)) {
      delete require.cache[require.resolve(i)]
    }
  })
}

// for mock server
function responseFake(url, type, respond) {
  return {
    url: new RegExp(`${url}`),
    type: type || 'get',
    response (req, res) {
      console.log('request invoke:' + req.path)
      res.json(Mock.mock(respond instanceof Function ? respond(req, res) : respond))
    }
  }
}

function register (router) {
  const proxyCount = require('./proxy').register(router)

  const { mocks } = require('./index.js')
  const mocksForServer = mocks.map(route => {
    return responseFake(route.url, route.type, route.response)
  })
  for (const mock of mocksForServer) {
    router[mock.type](mock.url, mock.response)
  }
}

module.exports = app => {
  app.use(process.env.VUE_APP_BASE_API, router)
  app.use(bodyParser.json())
  app.use(bodyParser.urlencoded({
    extended: true
  }))
  register(router)

  // watch files, hot reload mock server
  chokidar.watch(mockDir, {
    ignored: /mock-server/,
    ignoreInitial: true
  }).on('all', (event, path) => {
    if (event === 'change' || event === 'add') {
      try {
        router.stack = []

        // clear routes cache
        unregisterRoutes()

        register(router)

        console.log(chalk.magentaBright(`\n > Mock Server hot reload success! changed ${path}`))
      } catch (error) {
        console.log(chalk.redBright(error))
      }
    }
  })
}