require('colors')

const fs = require('fs')
const path = require('path')
const express = require('express')

const app = express()
const port = process.env.PORT || 3456

// Load the metadata for the local build of Atom
const buildPath = path.resolve(__dirname, '..', '..', 'out')
const packageJsonPath = path.join(buildPath, 'app', 'package.json')
if (!fs.existsSync(buildPath) || !fs.existsSync(packageJsonPath)) {
  console.log(`This script requires a full Atom build with release packages for the current platform in the following path:\n    ${buildPath}\n`)
  if (process.platform === 'darwin') {
    console.log(`Run this command before trying again:\n    script/build --compress-artifacts --test-sign\n\n`)
  } else if (process.platform === 'win32') {
    console.log(`Run this command before trying again:\n    script/build --create-windows-installer\n\n`)
  }
  process.exit(1)
}

const appMetadata = require(packageJsonPath)
const versionMatch = appMetadata.version.match(/-(beta|nightly)\d+$/)
const releaseChannel = versionMatch ? versionMatch[1] : 'stable'

console.log(`Serving ${appMetadata.productName} release assets (channel = ${releaseChannel})\n`.green)

function getMacZip (req, res) {
  console.log(`Received request for atom-mac.zip, sending it`)
  res.sendFile(path.join(buildPath, 'atom-mac.zip'))
}

function getMacUpdates (req, res) {
  if (req.query.version !== appMetadata.version) {
    const updateInfo = {
      name: appMetadata.version,
      pub_date: new Date().toISOString(),
      url: `http://localhost:${port}/mac/atom-mac.zip`,
      notes: '<p>No Details</p>'
    }

    console.log(`Received request for macOS updates (version = ${req.query.version}), sending\n`, updateInfo)
    res.json(updateInfo)
  } else {
    console.log(`Received request for macOS updates, sending 204 as Atom is up to date (version = ${req.query.version})`)
    res.sendStatus(204)
  }
}

function getReleasesFile (fileName) {
  return function (req, res) {
    console.log(`Received request for ${fileName}, version: ${req.query.version}`)
    if (req.query.version) {
      const versionMatch = (req.query.version || '').match(/-(beta|nightly)\d+$/)
      const versionChannel = (versionMatch && versionMatch[1]) || 'stable'
      if (releaseChannel !== versionChannel) {
        console.log(`Atom requested an update for version ${req.query.version} but the current release channel is ${releaseChannel}`)
        res.sendStatus(404)
        return
      }
    }

    res.sendFile(path.join(buildPath, fileName))
  }
}

function getNupkgFile (is64bit) {
  return function (req, res) {
    let nupkgFile = req.params.nupkg
    if (is64bit) {
      const nupkgMatch = nupkgFile.match(/atom-(.+)-(delta|full)\.nupkg/)
      if (nupkgMatch) {
        nupkgFile = `atom-x64-${nupkgMatch[1]}-${nupkgMatch[2]}.nupkg`
      }
    }

    console.log(`Received request for ${req.params.nupkg}, sending ${nupkgFile}`)
    res.sendFile(path.join(buildPath, nupkgFile))
  }
}

if (process.platform === 'darwin') {
  app.get('/mac/atom-mac.zip', getMacZip)
  app.get('/api/updates', getMacUpdates)
} else if (process.platform === 'win32') {
  app.get('/api/updates/RELEASES', getReleasesFile('RELEASES'))
  app.get('/api/updates/:nupkg', getNupkgFile())
  app.get('/api/updates-x64/RELEASES', getReleasesFile('RELEASES-x64'))
  app.get('/api/updates-x64/:nupkg', getNupkgFile(true))
} else {
  console.log(`The current platform '${process.platform}' doesn't support Squirrel updates, exiting.`.red)
  process.exit(1)
}

app.listen(port, () => {
  console.log(`Run Atom with ATOM_UPDATE_URL_PREFIX="http://localhost:${port}" set to test updates!\n`.yellow)
})