#!/usr/bin/env python

import os, sys, subprocess, locale, urllib2, gobject, time

import pygtk
pygtk.require('2.0')
import gtk

class TorBrowserLauncher:
  def __init__(self, current_tbb_version):
    # initialize the app
    self.current_tbb_version = current_tbb_version
    self.discover_arch_lang();
    self.build_paths();
    self.mkdirs();

    launch_gui = True

    # is TBB already installed?
    if os.path.isfile(self.paths['file']['start']) and os.access(self.paths['file']['start'], os.X_OK):
      # does the version file exist?
      if os.path.isfile(self.paths['file']['version']):
        installed_tbb_version = open(self.paths['file']['version']).read().strip()

        if installed_tbb_version == current_tbb_version:
          # current version is tbb is installed, launch it
          self.run(False)
          launch_gui = False
        elif installed_tbb_version < self.current_tbb_version:
          # there is a tbb upgrade available
          self.set_gui('task', "Your Tor Browser is out of date. Click Start to download the latest version from https://www.torproject.org.", ['download_tarball', 'download_tarball_sig', 'verify', 'extract', 'run'])
        else:
          # for some reason the installed tbb is newer than the current version?
          self.set_gui('error', "Something is wrong. The version of Tor Browser Bundle you have installed is newer than the current version?", [])

      else:
        # if tbb is installed but the version file doesn't exist, something is wrong
        self.set_gui('error', "Something is wrong. You have the Tor Browser Bundle installed, but the version file is missing.", [])

    # not installed
    else:
      # save the current version to the file
      open(self.paths['file']['version'], 'w').write(self.current_tbb_version)

      # are the tarball and sig already downloaded?
      if os.path.isfile(self.paths['file']['tarball']) and os.path.isfile(self.paths['file']['tarball_sig']):
        # start the gui with verify
        self.set_gui('task', "You already have Tor Browser Bundle downloaded, but it isn't installed yet.", ['verify', 'extract', 'run'])

      # first run
      else:
        self.set_gui('task', "The first time you run the Tor Browser Launcher you need to download the Tor Browser Bundle. Click Start to download it now from https://www.torproject.org/.", ['download_tarball', 'download_tarball_sig', 'verify', 'extract', 'run'])

    if launch_gui:
      self.build_ui()
      gtk.main()
  
  # discover the architecture and language
  def discover_arch_lang(self):
    # figure out the architecture
    self.architecture = subprocess.check_output(['arch']).strip('\n')

    # figure out the language
    available_languages = ['en-US', 'ar', 'de', 'es-ES', 'fa', 'fr', 'it', 'ko', 'nl', 'pl', 'pt-PT', 'ru', 'vi', 'zh-CN']
    self.language = locale.getdefaultlocale()[0].replace('_', '-')
    if self.language not in available_languages:
      self.language = self.language.split('-')[0]
      if self.language not in available_languages:
        for l in available_languages:
          if l[0:2] == self.language:
            self.language = l
    # if language isn't available, default to english
    if self.language not in available_languages:
      self.language = 'en-US'

  # build all relevant paths
  def build_paths(self):
    tbb_data = os.getenv('HOME')+'/.torbrowser'
    tarball_filename = 'tor-browser-gnu-linux-'+self.architecture+'-'+self.current_tbb_version+'-dev-'+self.language+'.tar.gz'

    self.paths = {
      'dir': {
        'data': tbb_data,
        'download': tbb_data+'/download',
        'tbb': tbb_data+'/tbb/'+self.architecture,
        'gpg': tbb_data+'/gpgtmp'
      },
      'file': {
        'version': tbb_data+'/version',
        'start': tbb_data+'/tbb/'+self.architecture+'/tor-browser_'+self.language+'/start-tor-browser',
        'tarball': tbb_data+'/download/'+tarball_filename,
        'tarball_sig': tbb_data+'/download/'+tarball_filename+'.asc',
        'verify': '/usr/share/torbrowser-launcher/verify.sh'
      },
      'url': {
        'tarball': 'https://www.torproject.org/dist/torbrowser/linux/'+tarball_filename,
        'tarball_sig': 'https://www.torproject.org/dist/torbrowser/linux/'+tarball_filename+'.asc'
      },
      'filename': {
        'tarball': tarball_filename,
        'tarball_sig': tarball_filename+'.asc'
      }
    }

  # create directories that don't exist
  def mkdirs(self):
    if os.path.exists(self.paths['dir']['download']) == False:
      os.makedirs(self.paths['dir']['download'])
    if os.path.exists(self.paths['dir']['tbb']) == False:
      os.makedirs(self.paths['dir']['tbb'])

  # there are different GUIs that might appear, this sets which one we want
  def set_gui(self, gui, message, tasks):
    self.gui = gui
    self.gui_message = message
    self.gui_tasks = tasks

  # build the application's UI
  def build_ui(self):
    self.timer = False

    # allow buttons to have icons
    settings = gtk.settings_get_default()
    settings.props.gtk_button_images = True

    # set up the window
    self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
    self.window.set_title("Tor Browser Launcher")
    self.window.set_position(gtk.WIN_POS_CENTER)
    self.window.set_border_width(10)
    self.window.connect("delete_event", self.delete_event)
    self.window.connect("destroy", self.destroy)

    self.box = gtk.VBox(False, 20)
    self.window.add(self.box)

    if self.gui == 'error':
      # labels
      self.label1 = gtk.Label( self.gui_message ); 
      self.label1.set_line_wrap(True)
      self.box.pack_start(self.label1, True, True, 0)
      self.label1.show()

      self.label2 = gtk.Label("You can fix the problem by deleting:\n"+self.paths['dir']['data']+"\n\nHowever, you will lose all your bookmarks and other Tor Browser preferences."); 
      self.label2.set_line_wrap(True)
      self.box.pack_start(self.label2, True, True, 0)
      self.label2.show()

      # exit button
      exit_image = gtk.Image()
      exit_image.set_from_stock(gtk.STOCK_CANCEL, gtk.ICON_SIZE_BUTTON)
      self.exit_button = gtk.Button("Exit")
      self.exit_button.set_image(exit_image)
      self.exit_button.connect("clicked", self.destroy, None)
      self.box.add(self.exit_button)
      self.exit_button.show()

    elif self.gui == 'task':
      # label
      self.label = gtk.Label( self.gui_message ); 
      self.label.set_line_wrap(True)
      self.box.pack_start(self.label, True, True, 0)
      self.label.show()
      
      # progress bar
      self.progressbar = gtk.ProgressBar(adjustment=None)
      self.progressbar.set_orientation(gtk.PROGRESS_LEFT_TO_RIGHT)
      self.progressbar.set_pulse_step(0.01)
      self.box.pack_start(self.progressbar, True, True, 0)

      # button box
      self.button_box = gtk.HButtonBox()
      self.button_box.set_layout(gtk.BUTTONBOX_SPREAD)
      self.box.pack_start(self.button_box, True, True, 0)
      self.button_box.show()

      # start button
      start_image = gtk.Image()
      start_image.set_from_stock(gtk.STOCK_APPLY, gtk.ICON_SIZE_BUTTON)
      self.start_button = gtk.Button("Start")
      self.start_button.set_image(start_image)
      self.start_button.connect("clicked", self.start, None)
      self.button_box.add(self.start_button)
      self.start_button.show()

      # exit button
      exit_image = gtk.Image()
      exit_image.set_from_stock(gtk.STOCK_CANCEL, gtk.ICON_SIZE_BUTTON)
      self.exit_button = gtk.Button("Exit")
      self.exit_button.set_image(exit_image)
      self.exit_button.connect("clicked", self.destroy, None)
      self.button_box.add(self.exit_button)
      self.exit_button.show()

    self.box.show()
    self.window.show();

  # start button clicked, begin tasks
  def start(self, widget, data=None):
    # disable the start button
    self.start_button.set_sensitive(False)

    # start running tasks
    self.gui_task_i = 0
    self.run_task()
    
  # run the next task in the task list
  def run_task(self):
    if self.gui_task_i >= len(self.gui_tasks):
      self.destroy(False)
      return

    task = self.gui_tasks[self.gui_task_i]
    
    # get ready for the next task
    self.gui_task_i += 1

    if task == 'download_tarball':
      print 'Downloading '+self.paths['url']['tarball']
      self.download('tarball', self.paths['url']['tarball'], self.paths['file']['tarball'])

    elif task == 'download_tarball_sig':
      print 'Downloading '+self.paths['url']['tarball_sig']
      self.download('signature', self.paths['url']['tarball_sig'], self.paths['file']['tarball_sig'])

    elif task == 'verify':
      print 'Verifying signature'
      self.verify()

    elif task == 'extract':
      print 'Extracting '+self.paths['filename']['tarball']
      self.extract()

    elif task == 'run':
      print 'Running '+self.paths['file']['start']
      self.run()
    
    elif task == 'start_over':
      print 'Starting download over again'
      self.start_over()


  def download(self, name, url, path):
    # initialize the progress bar
    self.progressbar.set_fraction(0) 
    self.progressbar.set_text('Downloading '+name)
    self.progressbar.show()

    # start the download
    self.dl_response = urllib2.urlopen(url);
    self.dl_total_size = self.dl_response.info().getheader('Content-Length').strip()
    self.dl_total_size = int(self.dl_total_size)
    self.dl_bytes_so_far = 0

    # set a timer to download more chunks
    self.timer = gobject.timeout_add(1, self.download_chunk, name)

    # open a file to write to
    self.file_download = open(path, 'w')

  def download_chunk(self, name):
    # download 10kb a time
    chunk = self.dl_response.read(10240)
    self.dl_bytes_so_far += len(chunk)
    self.file_download.write(chunk)

    if not chunk:
      self.file_download.close()
      # next task!
      self.run_task()
      return False

    percent = float(self.dl_bytes_so_far) / self.dl_total_size
    self.progressbar.set_fraction(percent)
    percent = round(percent*100, 2)
    self.progressbar.set_text("Downloaded %d%% of %s" % (percent, name))
    
    sys.stdout.write("Downloaded %d of %d bytes (%0.2f%%)\r" % (self.dl_bytes_so_far, self.dl_total_size, percent))

    if self.dl_bytes_so_far >= self.dl_total_size:
      sys.stdout.write('\n')

    return True

  def verify(self):
    # initialize the progress bar
    self.progressbar.set_fraction(0) 
    self.progressbar.set_text('Verifying Signature')
    self.progressbar.show()

    p = subprocess.Popen([self.paths['file']['verify'], self.paths['dir']['gpg'], self.paths['file']['tarball_sig']], stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    self.pulse_until_process_exits(p)

    output = p.stdout.read()
    
    if 'Good signature' in output:
      self.run_task();
    else:
      self.progressbar.hide()
      self.label.set_text("SIGNATURE VERIFICATION FAILED!\n\nYou might be under attack, or there might just be a networking problem. Click Start try the download again.")
      self.gui_tasks = ['start_over']
      self.gui_task_i = 0
      self.start_button.set_sensitive(True)

  def extract(self):
    # initialize the progress bar
    self.progressbar.set_fraction(0) 
    self.progressbar.set_text('Installing')
    self.progressbar.show()

    p = subprocess.Popen(['tar', '-xf', self.paths['file']['tarball'], '-C', self.paths['dir']['tbb']], stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    self.pulse_until_process_exits(p)

    self.run_task();

  def run(self, run_next_task = True):
    subprocess.Popen([self.paths['file']['start']])
    if run_next_task:
      self.run_task();

  # make the progress bar pulse until process p (a Popen object) finishes
  def pulse_until_process_exits(self, p):
    while p.poll() == None:
      time.sleep(0.01)
      self.progressbar.pulse()
      # redraw gtk
      while gtk.events_pending():
         gtk.main_iteration(False)

  # start over and download TBB again
  def start_over(self):
    self.label.set_text("Downloading Tor Browser Bundle over again.")
    self.gui_tasks = ['download_tarball', 'download_tarball_sig', 'verify', 'extract', 'run']
    self.gui_task_i = 0
    self.start(None)
  
  # exit
  def delete_event(self, widget, event, data=None):
    return False
  def destroy(self, widget, data=None):
    if self.timer:
      gobject.source_remove(self.timer)
    self.timer = False

    gtk.main_quit()

if __name__ == "__main__":
  print 'Tor Browser Launcher'
  print 'https://github.com/micahflee/torbrowser-launcher'

  current_tbb_version = '2.3.25-2'
  app = TorBrowserLauncher(current_tbb_version)