#!/usr/bin/env node
var fs = require('fs')
var path = require('path')
var updateNotifier = require('update-notifier')
var _db = require('underscore-db')
var yargs = require('yargs')
var chalk = require('chalk')
var got = require('got')
var pkg = require('../package.json')
var jsonServer = require('../src')

updateNotifier({packageName: pkg.name, packageVersion: pkg.version}).notify()

// Parse arguments
var argv = yargs
  .usage('$0 [options] <source>')
  .help('help').alias('help', 'h')
  .version(pkg.version, 'version').alias('version', 'v')
  .options({
    port: {
      alias: 'p',
      description: 'Set port',
      default: 3000
    },
    host: {
      alias: 'H',
      description: 'Set host',
      default: '0.0.0.0'
    },
    watch: {
      alias: 'w',
      description: 'Reload database on JSON file change'
    }
  })
  .boolean('w')
  .example('$0 db.json', '')
  .example('$0 file.js', '')
  .example('$0 http://example.com/db.json', '')
  .require(1, 'Missing <source> argument')
  .argv

function showResources (hostname, port, object) {
  for (var prop in object) {
    console.log(chalk.gray('  http://' + hostname + ':' + port + '/') + chalk.cyan(prop))
  }
}

function start (object, filename) {
  var port = process.env.PORT || argv.port
  var hostname = argv.host === '0.0.0.0' ? 'localhost' : argv.host

  console.log()
  showResources(hostname, port, object)
  console.log()
  console.log(
    'You can now go to ' + chalk.gray('http://' + hostname + ':' + port)
  )
  console.log()
  console.log(
    'Enter ' + chalk.cyan('s') + ' at any time to create a snapshot of the db'
  )


  process.stdin.resume()
  process.stdin.setEncoding('utf8')
  process.stdin.on('data', function (chunk) {
    if (chunk.trim().toLowerCase() === 's') {
      var file = 'db-' + Date.now() + '.json'
      _db.save(object, file)
      console.log('Saved snapshot to ' + chalk.cyan(file) + '\n')
    }
  })

  var router
  if (filename) {
    router = jsonServer.router(filename)
  } else {
    router = jsonServer.router(object)
  }

  if (filename && argv.watch) {
    console.log('Watching', chalk.cyan(source))

    var db = router.db
    var watchedDir = path.dirname(filename)
    var watchedFile = path.basename(filename)

    fs.watch(watchedDir, function (event, changedFile) {
      // lowdb generates 'rename' event on watchedFile
      // using it to know if file has been modified by the user
      if (event === 'change' && changedFile === watchedFile) {
        console.log(chalk.cyan(source), 'has changed, reloading database')

        try {
          var watchedFileObject = JSON.parse(fs.readFileSync(filename))
          db.object = watchedFileObject
          showResources(hostname, port, db.object)
        } catch (e) {
          console.log('Can\'t parse', chalk.cyan(source))
          console.log(e.message)
        }

        console.log()
      }
    })
  }
  console.log()


  var server = jsonServer.create()
  server.use(jsonServer.defaults)
  server.use(router)
  server.listen(port, argv.host)
}

// Set file and port
var source = argv._[0]

// Say hi, load file and start server
console.log(chalk.cyan('  {^_^} Hi!\n'))
console.log('Loading database from ' + chalk.cyan(source))

// Remote source
if (/^(http|https):/.test(source)) {
  got(source, function (err, data) {
    if (err) {
      console.log('Error', err)
      process.exit(1)
    }
    var object = JSON.parse(data)
    start(object)
  })
// JSON file
} else if (/\.json$/.test(source)) {
  var filename = process.cwd() + '/' + source
  var object = require(filename)
  start(object, filename)
// JS file
} else if (/\.js$/.test(source)) {
  var object = require(process.cwd() + '/' + source)()
  start(object)
}