import http from 'http'
import fs from 'fs'
import path from 'path'
import { deepStrictEqual } from 'assert'
import puppeteer from 'puppeteer-core'

const exercise = process.argv[2]
if (!exercise) throw Error(`usage: node test EXERCISE_NAME`)
const PORT = 9898
const config = {
  headless: false,
  executablePath: process.env.CHROME_PATH || '/usr/bin/google-chrome',
}

const mediaTypes = {
  jpg: 'image/jpeg',
  png: 'image/png',
  html: 'text/html',
  css: 'text/css',
  js: 'application/javascript',
  json: 'application/json',
}

const server = http
  .createServer(({ url, method }, response) => {
    console.log(method + ' ' + url)
    const filepath = url.endsWith(`${exercise}/${exercise}.js`)
      ? path.join('.', url.slice(exercise.length + 1))
      : path.join('./subjects', url)
    const ext = path.extname(filepath)
    response.setHeader('Content-Type', mediaTypes[ext.slice(1)] || 'text/plain')

    const stream = fs
      .createReadStream(filepath)
      .pipe(response)
      .once('error', (err) => {
        console.log(err)
        response.statusCode = 500 // handle 404 ?
        response.end('oopsie')
      })
  })
  .listen(PORT, async (err) => {
    let browser,
      code = 0
    try {
      err && (console.error(err.stack) || process.exit(1))
      const { setup = () => {}, tests } = await import(`./${exercise}_test.js`)
      browser = await puppeteer.launch(config)

      const [page] = await browser.pages()
      await page.goto(`http://localhost:${PORT}/${exercise}/index.html`)
      const context = await setup({ page })

      browser
        .defaultBrowserContext()
        .overridePermissions(`http://localhost:${PORT}`, ['clipboard-read'])

      for (const [n, test] of tests.entries()) {
        try {
          await test({ page, eq: deepStrictEqual, ...context })
        } catch (err) {
          console.log(`test #${n} failed:`)
          console.log(test.toString())
          throw err
        }
      }
    } catch (err) {
      code = 1
      console.log(err.stack)
    } finally {
      await (browser && browser.close())
      server.close()
      process.exit(code)
    }
  })