#!/usr/bin/python3

from __future__ import print_function

import warnings
warnings.filterwarnings("ignore", "apt API not stable yet", FutureWarning)

from DistUpgrade.DistUpgradeVersion import VERSION
from DistUpgrade.DistUpgradeGettext import gettext as _

from UpdateManager.Core.MetaRelease import MetaReleaseCore
from optparse import OptionParser
import locale
import gettext

import apt
import os
import subprocess
import sys
import time
from UpdateManager.Core.utils import init_proxy

RELEASE_AVAILABLE=0
NO_RELEASE_AVAILABLE=1


def get_fetcher(frontend, new_dist, datadir):
    if frontend == "DistUpgradeViewGtk3":
        from DistUpgrade.DistUpgradeFetcher import DistUpgradeFetcherGtk
        from DistUpgrade.GtkProgress import GtkAcquireProgress
        progress = GtkAcquireProgress(
            None,
            datadir,
            _("Downloading the release upgrade tool"))
        return DistUpgradeFetcherGtk(new_dist=new_dist,
                                     progress=progress,
                                     parent=None,
                                     datadir=datadir)
    elif frontend == "DistUpgradeViewKDE":
        print("kde")
        from DistUpgrade.DistUpgradeFetcherKDE import DistUpgradeFetcherKDE
        from DistUpgrade.DistUpgradeFetcherKDE import KDEAcquireProgressAdapter
        progress = KDEAcquireProgressAdapter(
            parent=None,
            datadir=datadir,
            label=_("Downloading the release upgrade tool"))
        return DistUpgradeFetcherKDE(new_dist=new_dist,
                                     progress=progress,
                                     parent=None,
                                     datadir=datadir)
    else:
        from DistUpgrade.DistUpgradeFetcherCore import DistUpgradeFetcherCore
        import apt
        progress = apt.progress.text.AcquireProgress()
        return DistUpgradeFetcherCore(new_dist, progress)


if __name__ == "__main__":

  #FIXME: Workaround a bug in optparser which doesn't handle unicode/str
  #       correctly, see http://bugs.python.org/issue4391
  #       Should be resolved by Python3
  gettext.bindtextdomain("ubuntu-release-upgrader", "/usr/share/locale")
  gettext.textdomain("ubuntu-release-upgrader")
  translation = gettext.translation("ubuntu-release-upgrader", fallback=True)

  try:
    locale.setlocale(locale.LC_ALL, "")
  except:
    pass

  init_proxy()

  # when run as "check-new-release" we go into "check only" mode
  check_only = sys.argv[0].endswith("check-new-release")

  parser = OptionParser()
  parser.add_option ("-V", "--version", action="store_true",
                     dest="show_version", default=False,
                     help=_("Show version and exit"))
  parser.add_option ("-d", "--devel-release", action="store_true",
                     dest="devel_release", default=False,
                     help=_("If using the latest supported release, "
                            "upgrade to the development release"))
  parser.add_option ("--data-dir", "",
                     default="/usr/share/ubuntu-release-upgrader/",
                     help=_("Directory that contains the data files"))
  parser.add_option ("-p", "--proposed", action="store_true",
                     dest="proposed_release", default=False,
                     help=_("Try upgrading to the latest release using "
                            "the upgrader from $distro-proposed"))
  parser.add_option ("-m", "--mode", default="server",
                     dest="mode", 
                     help=_("Run in a special upgrade mode.\n"
                            "Currently 'desktop' for regular upgrades of "
                            "a desktop system and 'server' for server "
                            "systems are supported."))
  parser.add_option ("-f", "--frontend", default="DistUpgradeViewText",
                     dest="frontend", 
                     help=_("Run the specified frontend"))
  parser.add_option ("-c", "--check-dist-upgrade-only", action="store_true",
                     default=check_only,
                     help=_("Check only if a new distribution release is "
                            "available and report the result via the "
                            "exit code"))
  parser.add_option ("--allow-third-party", default=False,
                     action="store_true", dest="allow_third_party",
                     help=_("Try the upgrade with third party "
                            "mirrors and repositories enabled "
                            "instead of commenting them out."))
  parser.add_option ("-q", "--quiet", default=False, action="store_true",
                     dest="quiet")
  parser.add_option ("-e", "--env",
                     help=_("A comma-separated list of environment variables "
                            "(e.g. VAR1=VALUE1,VAR2=VALUE2) that should be set "
                            "during the upgrade."))

  (options, args) = parser.parse_args()


  if options.show_version:
    print("%s: version %s" % (os.path.basename(sys.argv[0]), VERSION))
    sys.exit(0)

  if options.devel_release and options.proposed_release:
    print(_("The options --devel-release and --proposed are"))
    print(_("mutually exclusive. Please use only one of them."))
    sys.exit(1)

  if not options.quiet:
    print(_("Checking for a new Ubuntu release"))

  m = MetaReleaseCore(useDevelopmentRelease=options.devel_release,
                      useProposed=options.proposed_release)
  # this will timeout eventually
  m.downloaded.wait()

  # make sure to inform the user if his distro is no longer supported
  # this will make it appear in motd (that calls do-release-upgrade in
  #  check-new-release mode)
  if m.no_longer_supported is not None:
    url = "http://www.ubuntu.com/releaseendoflife"
    print(_("Your Ubuntu release is not supported anymore."))
    print(_("For upgrade information, please visit:\n"
            "%(url)s\n") % { 'url' : url })

  # now inform about a new release
  if m.new_dist is None:
    if not options.quiet:
      if m.prompt == 'never':
        print(_("In /etc/update-manager/release-upgrades Prompt "))
        print(_("is set to never so upgrading is not possible."))
      elif m.prompt == 'lts':
        print(_("There is no development version of an LTS available."))
        print(_("To upgrade to the latest non-LTS development release "))
        print(_("set Prompt=normal in /etc/update-manager/release-upgrades."))
      elif options.devel_release:
        print(_("Upgrades to the development release are only "))
        print(_("available from the latest supported release."))
      else:
        print(_("No new release found."))
    sys.exit(NO_RELEASE_AVAILABLE)

  if m.new_dist.upgrade_broken:
    if not options.quiet:
      print(_("Release upgrade not possible right now"))
      print(_("The release upgrade can not be performed currently, "
              "please try again later. The server reported: '%s'") % m.new_dist.upgrade_broken)
    sys.exit(NO_RELEASE_AVAILABLE)

  # we have a new dist
  if options.check_dist_upgrade_only:
    print(_("New release '%s' available.") % m.new_dist.version)
    print(_("Run 'do-release-upgrade' to upgrade to it."))
    sys.exit(RELEASE_AVAILABLE)

  cache = apt.Cache()
  cache.open()
  install_count = 0
  upgradable = [pkg for pkg in cache if pkg.is_upgradable]
  for pkg in upgradable:
    if 'Phased-Update-Percentage' in pkg.candidate.record:
      # P-U-P does not exist if it is fully phased
      continue
    else:
      install_count += 1
      # one upgradeable package is enough to stop the dist-upgrade
      break
  if install_count > 0:
    if not options.quiet:
      print(_("Please install all available updates "
              "for your release before upgrading."))
    sys.exit(1)
  if os.path.exists('/var/run/reboot-required.pkgs'):
    reboot = False
    with open('/var/run/reboot-required.pkgs', 'rb') as f:
        for line in f:
            # In certain cases, we need to reboot the system before proceeding
            # with the dist upgrade after the kernel is upgraded as otherwise
            # building of some dkms modules can fail.
            if (line == b'libc6\n' or line == b'linux-base\n' or
                    line.startswith(b'linux-image-')):
                reboot = True
                break
    if reboot:
      if not options.quiet:
        print(_("You have not rebooted after updating a package which "
                "requires a reboot. Please reboot before upgrading."))
      sys.exit(1)

  if options.allow_third_party:
    # the env variable is used by code in the dist-upgrader tarball
    os.environ["RELEASE_UPGRADER_ALLOW_THIRD_PARTY"] = "True"

  if options.env:
      for env in options.env.split(','):
          parts = env.split('=')
          if len(parts) < 2:
              continue

          # The value itself may contain '='.
          os.environ[parts[0]] = '='.join(parts[1:])

  # GTK 3 fetcher starts setting up the the GUI and KDE GUI needs to start GUI
  # later, too.
  if (options.frontend in {"DistUpgradeViewGtk3", "DistUpgradeViewKDE"} and
      os.getuid() != 0):
    if 'WAYLAND_DISPLAY' in os.environ:
        subprocess.run(['xhost', '+si:localuser:root'])
    # this is needed because pkexec doesn't pass on the env
    if 'RELEASE_UPGRADER_ALLOW_THIRD_PARTY' in os.environ:
        sys.argv.append('--allow-third-party')

    # Some extra environment variables need to be passed, but we need
    # to do this explicitly with do-release-upgrade because pkexec
    # does not provide such functionality.
    extra_env_vars = [
        'DBUS_SESSION_BUS_ADDRESS=%s' % os.getenv('DBUS_SESSION_BUS_ADDRESS', ''),
        'XDG_SESSION_TYPE=%s' % os.getenv('XDG_SESSION_TYPE', ''),
    ]
    sys.argv.append('--env=%s' % ','.join(extra_env_vars))

    os.execv("/usr/bin/pkexec", ["pkexec"] + sys.argv)

  fetcher = get_fetcher(options.frontend, m.new_dist, options.data_dir)
  fetcher.run_options += ["--mode=%s" % options.mode,
                          "--frontend=%s" % options.frontend,
                          ]
  if options.devel_release:
    fetcher.run_options.append("--devel-release")
  fetcher.run()