module.exports = {
  init,
  hasTray
}

var cp = require('child_process')
var path = require('path')
var electron = require('electron')

var app = electron.app

var windows = require('./windows')

var trayIcon

function init () {
  // OS X has no tray icon
  if (process.platform === 'darwin') return

  // On Linux, asynchronously check for libappindicator1
  if (process.platform === 'linux') {
    checkLinuxTraySupport(function (supportsTray) {
      if (supportsTray) createTrayIcon()
    })
  }

  // Windows always supports minimize-to-tray
  if (process.platform === 'win32') createTrayIcon()
}

function hasTray () {
  return !!trayIcon
}

function createTrayIcon () {
  trayIcon = new electron.Tray(path.join(__dirname, '..', 'static', 'WebTorrentSmall.png'))

  // On Windows, left click to open the app, right click for context menu
  // On Linux, any click (right or left) opens the context menu
  trayIcon.on('click', showApp)

  // Show the tray context menu, and keep the available commands up to date
  updateTrayMenu()
  windows.main.on('show', updateTrayMenu)
  windows.main.on('hide', updateTrayMenu)
}

function checkLinuxTraySupport (cb) {
  // Check that we're on Ubuntu (or another debian system) and that we have
  // libappindicator1. If WebTorrent was installed from the deb file, we should
  // always have it. If it was installed from the zip file, we might not.
  cp.exec('dpkg --get-selections libappindicator1', function (err, stdout) {
    if (err) return cb(false)
    // Unfortunately there's no cleaner way, as far as I can tell, to check
    // whether a debian package is installed:
    cb(stdout.endsWith('\tinstall\n'))
  })
}

function updateTrayMenu () {
  var showHideMenuItem
  if (windows.main.isVisible()) {
    showHideMenuItem = { label: 'Hide to tray', click: hideApp }
  } else {
    showHideMenuItem = { label: 'Show', click: showApp }
  }
  var contextMenu = electron.Menu.buildFromTemplate([
    showHideMenuItem,
    { label: 'Quit', click: () => app.quit() }
  ])
  trayIcon.setContextMenu(contextMenu)
}

function showApp () {
  windows.main.show()
}

function hideApp () {
  windows.main.hide()
  windows.main.send('dispatch', 'backToList')
}