#!/usr/bin/env node
// usage: github-lint
//
// Run ESLint and Flow on project.

const childProcess = require('child_process')
const fs = require('fs')
const path = require('path')
const supportsColors = require('supports-color')

const hasBasicColorSupport = supportsColors.stdout.hasBasic && supportsColors.stderr.hasBasic

function execFile(command, args) {
  return new Promise(resolve => {
    childProcess.execFile(command, args, {maxBuffer: 1024 ** 2}, (error, stdout, stderr) => {
      resolve({code: error ? error.code : 0, stdout, stderr})
    })
  })
}

;(async function() {
  let runs = 0
  const codes = []
  const commands = []

  const packageJson = fs.existsSync('package.json') ? require(path.join(process.cwd(), 'package.json')) : {}

  let eslintOptions = ['--report-unused-disable-directives', '.']

  if (hasBasicColorSupport) {
    eslintOptions = eslintOptions.concat(['--color'])
  }

  const isTypeScriptProject = fs.existsSync('tsconfig.json')

  if (isTypeScriptProject) {
    eslintOptions = eslintOptions.concat(['--ext', '.js,.ts,.tsx'])
  }

  commands.push(['eslint', eslintOptions])

  if (isTypeScriptProject) {
    commands.push(['tsc', ['--noEmit']])
  }

  if (fs.existsSync('.flowconfig')) {
    commands.push(['flow', ['check']])
  }

  if (packageJson && packageJson.flow && packageJson.flow.coverageThreshold) {
    commands.push(['flow-coverage', []])
  }

  for (const [command, args] of commands) {
    if (runs > 0) process.stderr.write('\n')
    process.stderr.write(`> ${command} ${args.join(' ')}\n`)

    const {code, stdout, stderr} = await execFile(command, args)
    codes.push(code)
    if (stderr) process.stderr.write(stderr)
    if (stdout) process.stdout.write(stdout)

    runs++
  }

  const nonzero = codes.find(code => code !== 0)
  if (nonzero) {
    process.stderr.write(`\nCommand failed: ${nonzero}\n`)
    process.exit(nonzero)
  }
})().catch(error => {
  setTimeout(() => {
    throw error
  })
})