#!/usr/bin/env python

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

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

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

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

    launch_gui = True

    # load settings
    if self.load_settings():
      self.build_paths(self.settings['latest_version'])

      # how long was it since the last update check?
      # 86400 seconds = 24 hours
      current_timestamp = int(time.time())
      if current_timestamp - self.settings['last_update_check_timestamp'] >= 86400:
        # check for update
        self.set_gui('task', "Checking for Tor Browser update.", 
          ['download_update_check', 
           'attempt_update'])

      else:
        # no need to check for update
        self.start_launcher()

    else:
      self.set_gui('error', "Error loading settings. Delete ~/.torbrowser and try again.", [])

    if launch_gui:
      # set up the window
      self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
      self.window.set_title("Tor Browser")
      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)

      # build the rest of the UI
      self.build_ui()
      gtk.main()

  # download or run TBB
  def start_launcher(self):
    # is TBB already installed?
    if os.path.isfile(self.paths['file']['start']) and os.access(self.paths['file']['start'], os.X_OK):
      if self.settings.installed_version == self.settings.latest_version:
        # current version of tbb is installed, launch it
        self.run(False)
        launch_gui = False
      elif self.settings.installed_version < self.settings.latest_version:
        # there is a tbb upgrade available
        self.set_gui('task', "Your Tor Browser is out of date.", 
          ['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?", [])

    # not installed
    else:
      # 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', "Installing Tor Browser.", 
          ['verify', 
           'extract', 
           'run'])

      # first run
      else:
        self.set_gui('task', "Downloading and installing Tor Browser.", 
          ['download_tarball', 
           'download_tarball_sig', 
           'verify', 
           'extract', 
           'run'])

  # discover the architecture and language
  def discover_arch_lang(self):
    # figure out the architecture
    (sysname, nodename, release, version, machine) = os.uname()
    self.architecture = machine

    # figure out the language
    available_languages = ['en-US', 'ar', 'de', 'es-ES', 'fa', 'fr', 'it', 'ko', 'nl', 'pl', 'pt-PT', 'ru', 'vi', 'zh-CN']
    default_locale = locale.getdefaultlocale()[0]
    if default_locale == None:
      self.language = 'en-US'
    else:
      self.language = default_locale.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_version = None):
    tbb_data = os.getenv('HOME')+'/.torbrowser'

    if tbb_version:
      tarball_filename = 'tor-browser-gnu-linux-'+self.architecture+'-'+tbb_version+'-dev-'+self.language+'.tar.gz'
      self.paths['file']['tarball'] = tbb_data+'/download/'+tarball_filename
      self.paths['file']['tarball_sig'] = tbb_data+'/download/'+tarball_filename+'.asc'
      self.paths['url']['tarball'] = 'https://www.torproject.org/dist/torbrowser/linux/'+tarball_filename
      self.paths['url']['tarball_sig'] = 'https://www.torproject.org/dist/torbrowser/linux/'+tarball_filename+'.asc'
      self.paths['filename']['tarball'] = tarball_filename
      self.paths['filename']['tarball_sig'] = tarball_filename+'.asc'

    else:
      self.paths = {
        'dir': {
          'data': tbb_data,
          'download': tbb_data+'/download',
          'tbb': tbb_data+'/tbb/'+self.architecture,
          'gpg': tbb_data+'/gpgtmp'
        },
        'file': {
          'settings': tbb_data+'/settings',
          'version': tbb_data+'/version',
          'start': tbb_data+'/tbb/'+self.architecture+'/tor-browser_'+self.language+'/start-tor-browser',
          'update_check': tbb_data+'/download/RecommendedTBBVersions',
          'verify': '/usr/share/torbrowser-launcher/verify.sh'
        },
        'url': {
          'update_check': 'https://check.torproject.org/RecommendedTBBVersions'
        },
        'filename': {}
      }

  # 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, autostart=True):
    self.gui = gui
    self.gui_message = message
    self.gui_tasks = tasks
    self.gui_autostart = autostart

  # set all gtk variables to False
  def clear_ui(self):
    if self.timer:
      gobject.source_remove(self.timer)
    self.timer = False

    if self.box:
      self.box.destroy()
    self.box = False

    self.label1 = False
    self.label2 = False
    self.label = False
    self.progressbar = False
    self.button_box = False
    self.start_button = False
    self.exit_button = False

  # build the application's UI
  def build_ui(self):
    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)
      if not self.gui_autostart:
        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()

    if self.gui_autostart:
      self.start(None)

  # start button clicked, begin tasks
  def start(self, widget, data=None):
    # disable the start button
    if self.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):
    self.refresh_gtk()

    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_update_check':
      print 'Downloading '+self.paths['url']['update_check']
      self.download('update check', self.paths['url']['update_check'], self.paths['file']['update_check'])
    
    if task == 'attempt_update':
      print 'Attempting to update'
      self.attempt_update()

    elif 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()
    self.refresh_gtk()

    # 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))
    self.refresh_gtk()
    
    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 attempt_update(self):
    # load the update check file
    try:
      versions = json.load(open(self.paths['file']['update_check']))
      latest_version = None

      end = '-Linux-%s' % self.architecture
      for version in versions:
        if str(version).find(end) != -1:
          latest_version = version

      if latest_version:
        self.settings.latest_version = latest_version[:-len(end)]
        self.settings.last_update_check_timestamp = int(time.time())
        self.save_settings()
        self.build_paths(self.settings['latest_version'])
        self.start_launcher()

      else:
        # failed to find the latest version
        self.set_gui('error', "Error checking for updates.", [])
    
    except:
      # not a valid JSON object
      self.set_gui('error', "Error checking for updates.", [])

    # now start over
    self.clear_ui()
    self.build_ui()

  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.show()
      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()
      self.refresh_gtk()

  # 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)

  # load settings
  def load_settings(self):
    if os.path.isfile(self.paths['file']['settings']):
      self.settings = pickle.load(open(self.paths['file']['settings']))
      # sanity checks
      if not 'installed_version' in self.settings:
        return False
      if not 'latest_version' in self.settings:
        return False
      if not 'last_update_check_timestamp' in self.settings:
        return False
    else:
      self.settings = {
        'installed_version': False,
        'latest_version': '0',
        'last_update_check_timestamp': 0
      }
      self.save_settings()
    return True

  # save settings
  def save_settings(self):
    pickle.dump(self.settings, open(self.paths['file']['settings'], 'w'))
    return True
  
  # refresh gtk
  def refresh_gtk(self):
    while gtk.events_pending():
       gtk.main_iteration(False)

  # 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__":
  tor_browser_launcher_version = '0.1'

  print 'Tor Browser Launcher'
  print 'version %s' % (tor_browser_launcher_version)
  print 'https://github.com/micahflee/torbrowser-launcher'

  app = TorBrowserLauncher()