# -*- coding: utf-8; Mode: Python; indent-tabs-mode: nil; tab-width: 4 -*-
# -*- kate: indent-mode python; space-indent true; indent-width 4; backspace-indents true
#
# Copyright (C) 2006, 2007, 2008, 2009 Canonical Ltd.
#
# Author(s):
#   Jonathan Riddell <jriddell@ubuntu.com>
#   Mario Limonciello <superm1@ubuntu.com>
#   Roman Shtylman <shtylman@gmail.com>
#
# This file is part of Ubiquity.
#
# Ubiquity is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free
# Software Foundation; either version 2 of the License, or at your option)
# any later version.
#
# Ubiquity is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along
# with Ubiquity; if not, write to the Free Software Foundation, Inc., 51
# Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import sys
import os
import traceback
import syslog
import atexit
import signal
import dbus

# kde gui specifics
from PyQt4 import QtCore, QtGui, uic

#import all our custom kde components
from ubiquity.frontend.kde_components import ProgressDialog, SqueezeLabel

from ubiquity import filteredcommand, i18n
from ubiquity import misc
from ubiquity.plugin import Plugin
from ubiquity.components import partman_commit, install, plugininstall
import ubiquity.progressposition
import ubiquity.frontend.base
from ubiquity.frontend.base import BaseFrontend

# Define global path
PATH = '/usr/share/ubiquity'

# Define locale path
LOCALEDIR = "/usr/share/locale"

#currently using for testing, will remove
UIDIR = os.path.join(PATH, 'qt')


class UbiquityUI(QtGui.QMainWindow):
    def __init__(self, parent=None):
        QtCore.QTextCodec.setCodecForCStrings(
            QtCore.QTextCodec.codecForName("UTF-8"))
        QtGui.QMainWindow.__init__(self, parent)
        uic.loadUi(os.path.join(UIDIR, "app.ui"), self)

        # QProcessManager sets a SIGCHLD handler without SA_RESTART; this
        # can cause ubiquity crashes, because Python's subprocess module
        # (and indeed much of Python in general) is not EINTR-safe.  Force
        # this to be restartable.
        signal.siginterrupt(signal.SIGCHLD, False)

        distro_name = "Kubuntu"
        distro_release = ""

        ## setup the release and codename
        fp = open("/etc/lsb-release", 'r')

        for line in fp:
            if "DISTRIB_ID=" in line:
                name = str.strip(line.split("=")[1], '\n')
                if name != "Ubuntu":
                    distro_name = name
            elif "DISTRIB_RELEASE=" in line:
                distro_release = str.strip(line.split("=")[1], '\n')

        fp.close()

        self.distro_name_label.setText(distro_name)
        self.distro_release_label.setText(distro_release)

        self.minimize_button.clicked.connect(self.showMinimized)

        self.setWindowTitle("%s %s" % (distro_name, distro_release))

        # don't use stylesheet cause we want to scale the wallpaper for various
        # screen sizes as well as support larger screens
        self.bgImage = QtGui.QImage("/usr/share/wallpapers/kde-default.png")
        self.scaledBgImage = self.bgImage

    def paintEvent(self, pe):
        p = QtGui.QPainter(self)
        p.drawImage(0, 0, self.scaledBgImage)

    def resizeEvent(self, re):
        self.scaledBgImage = self.bgImage.scaled(self.width(), self.height(),
                                        QtCore.Qt.KeepAspectRatioByExpanding,
                                        QtCore.Qt.SmoothTransformation)

    def setWizard(self, wizardRef):
        self.wizard = wizardRef

    def closeEvent(self, event):
        if not self.wizard.on_quit_clicked():
            event.ignore()

class Controller(ubiquity.frontend.base.Controller):
    def translate(self, lang=None, just_me=True, not_me=False, reget=False):
        if lang:
            self._wizard.locale = lang
        self._wizard.translate_pages(lang, just_me, not_me, reget)

    def allow_go_forward(self, allowed):
        self._wizard.allow_go_forward(allowed)

    def allow_go_backward(self, allowed):
        self._wizard.allow_go_backward(allowed)

    def allow_change_step(self, allowed):
        self._wizard.allow_change_step(allowed)

    def allowed_change_step(self):
        return self._wizard.allowed_change_step

    def go_forward(self):
        self._wizard.ui.next.click()

    def go_backward(self):
        self._wizard.ui.back.click()

    def go_to_page(self, widget):
        self._wizard.set_current_page(self._wizard.stackLayout.indexOf(widget))

    def toggle_top_level(self):
        if self._wizard.ui.isVisible():
            self._wizard.ui.hide()
        else:
            self._wizard.ui.show()
        self._wizard.refresh()

    def get_string(self, name, lang=None, prefix=None):
        return self._wizard.get_string(name, lang, prefix)

    def setNextButtonTextInstallNow(self, checked):
        self._wizard.ui.next.setText(self.get_string('install_button').replace('_', '&', 1))
        self._wizard.ui.next.setIcon(self._wizard.applyIcon)

    def setNextButtonTextNext(self, checked):
        self._wizard.ui.next.setText(self.get_string('next').replace('_', '&', 1))
        self._wizard.ui.next.setIcon(self._wizard.forwardIcon)

class Wizard(BaseFrontend):

    def __init__(self, distro):
        BaseFrontend.__init__(self, distro)

        self.previous_excepthook = sys.excepthook
        sys.excepthook = self.excepthook

        self.app = QtGui.QApplication([])
        with open(os.path.join(UIDIR, "style.qss")) as style:
            self.app.setStyleSheet(style.read())

        self.app.setWindowIcon(QtGui.QIcon(
         "/usr/share/icons/hicolor/128x128/apps/ubiquity.png"))
        import dbus.mainloop.qt
        dbus.mainloop.qt.DBusQtMainLoop(set_as_default=True)

        self.ui = UbiquityUI()

        # handle smaller screens (old school eee pc
        if (QtGui.QApplication.desktop().screenGeometry().height() < 560):
            self.ui.main_frame.setFixedHeight(470)
            self.ui.main_frame.setStyleSheet(file(os.path.join(UIDIR, "style_small.qss")).read())

        # initially the steps widget is not visible
        # it becomes visible once the first step becomes active
        self.ui.steps_widget.setVisible(False)
        self.ui.content_widget.setVisible(False)

        if 'UBIQUITY_GREETER' in os.environ:
            self.ui.minimize_button.hide()

        self.ui.setWindowState(self.ui.windowState() ^ QtCore.Qt.WindowFullScreen)

        self.ui.setWizard(self)
        # self.ui.setWindowFlags(QtCore.Qt.Window |
        # QtCore.Qt.CustomizeWindowHint | QtCore.Qt.WindowTitleHint |
        # QtCore.Qt.WindowMinMaxButtonsHint)

        #hide the minimize button if in "install only" mode
        if 'UBIQUITY_ONLY' in os.environ or 'UBIQUITY_GREETER' in os.environ:
            self.ui.minimize_button.setVisible(False)

        self.stackLayout = QtGui.QStackedLayout(self.ui.widgetStack)

        self.pages = []
        self.pagesindex = 0
        self.pageslen = 0
        for mod in self.modules:
            if hasattr(mod.module, 'PageKde'):
                mod.ui_class = mod.module.PageKde
                mod.controller = Controller(self)
                mod.ui = mod.ui_class(mod.controller)
                widgets = mod.ui.get('plugin_widgets')
                optional_widgets = mod.ui.get('plugin_optional_widgets')
                breadcrumb = mod.ui.get('plugin_breadcrumb')
                if widgets or optional_widgets:
                    def fill_out(widget_list):
                        rv = []
                        if not isinstance(widget_list, list):
                            widget_list = [widget_list]
                        for w in widget_list:
                            if not w: continue
                            if not isinstance(w, str):
                                # Until we ship with no pre-built pages, insert
                                # at 'beginning'
                                self.stackLayout.insertWidget(self.pageslen, w)
                            elif hasattr(self.ui, w):
                                w = getattr(self.ui, w)
                            rv.append(w)
                        return rv
                    mod.widgets = fill_out(widgets)
                    mod.optional_widgets = fill_out(optional_widgets)
                    if not hasattr(mod.ui, 'plugin_breadcrumb'):
                        breadcrumb = '------' # just a placeholder
                    if breadcrumb:
                        mod.breadcrumb_question = breadcrumb
                        mod.breadcrumb = SqueezeLabel.SqueezeLabel()
                        mod.breadcrumb.setObjectName(mod.breadcrumb_question)
                        label_index = self.ui.steps_widget.layout().count() - 2 # Room for install crumb
                        self.ui.steps_widget.layout().insertWidget(label_index, mod.breadcrumb)
                    else:
                        mod.breadcrumb_question = None
                        mod.breadcrumb = None # page intentionally didn't want a label (intro)
                    self.pageslen += 1
                    self.pages.append(mod)
        self.user_pageslen = self.pageslen

        # declare attributes
        self.language_questions = (
            'live_installer',
            'quit',
            'back',
            'next',
            'warning_dialog',
            'warning_dialog_label',
            'cancelbutton',
            'exitbutton',
            'install_process_label'
        )

        self.current_page = None
        self.first_seen_page = None
        self.allowed_change_step = True
        self.allowed_go_backward = True
        self.allowed_go_forward = True
        self.stay_on_page = False
        self.mainLoopRunning = False
        self.progress_position = ubiquity.progressposition.ProgressPosition()
        self.progress_cancelled = False
        self.previous_partitioning_page = self.step_index("stepPartAuto")
        self.installing = False
        self.installing_no_return = False
        self.returncode = 0
        self.backup = False
        self.history = []
        self.progressDialog = ProgressDialog.ProgressDialog(0, 0, self.ui)
        self.finished_installing = False
        self.finished_pages = False
        self.parallel_db = None

        self.laptop = misc.execute("laptop-detect")

        # set default language
        self.locale = i18n.reset_locale(self)

        self.socketNotifierRead = {}
        self.socketNotifierWrite = {}
        self.socketNotifierException = {}
        self.debconf_callbacks = {}    # array to keep callback functions needed by debconf file descriptors

        self.ui.setWindowIcon(QtGui.QIcon(
         "/usr/share/icons/hicolor/128x128/apps/ubiquity.png"))
        self.allow_go_backward(False)

        if not 'UBIQUITY_AUTOMATIC' in os.environ:
            self.ui.show()

        self.stop_debconf()
        self.translate_widgets(reget=True)

        if self.custom_title:
            self.ui.setWindowTitle(self.custom_title)
        elif self.oem_config:
            self.ui.setWindowTitle(self.get_string('oem_config_title'))
        elif self.oem_user_config:
            self.ui.setWindowTitle(self.get_string('oem_user_config_title'))
            self.ui.setWindowIcon(QtGui.QIcon(
          "/usr/share/icons/oxygen/128x128/categories/preferences-system.png"))
            flags = self.ui.windowFlags() ^ QtCore.Qt.WindowMinMaxButtonsHint
            if hasattr(QtCore.Qt, 'WindowCloseButtonHint'):
                flags = flags ^ QtCore.Qt.WindowCloseButtonHint
            self.ui.setWindowFlags(flags)
            self.ui.quit.hide()
            # TODO cjwatson 2010-04-07: provide alternative strings instead
            self.ui.install_process_label.hide()
            self.ui.breadcrumb_install.hide()

        self.forwardIcon = QtGui.QIcon(
         "/usr/share/icons/oxygen/128x128/actions/go-next.png")
        self.ui.next.setIcon(self.forwardIcon)

        #Used for the last step
        self.applyIcon = QtGui.QIcon(
         "/usr/share/icons/oxygen/128x128/actions/dialog-ok-apply.png")

        backIcon = QtGui.QIcon(
         "/usr/share/icons/oxygen/128x128/actions/go-previous.png")
        self.ui.back.setIcon(backIcon)

        quitIcon = QtGui.QIcon(
         "/usr/share/icons/oxygen/48x48/actions/dialog-close.png")
        self.ui.quit.setIcon(quitIcon)

        self.ui.progressBar.hide()
        self.ui.progressCancel.hide()

        misc.add_connection_watch(self.network_change)

    def excepthook(self, exctype, excvalue, exctb):
        """Crash handler."""

        if (issubclass(exctype, KeyboardInterrupt) or
            issubclass(exctype, SystemExit)):
            return

        tbtext = ''.join(traceback.format_exception(exctype, excvalue, exctb))
        syslog.syslog(syslog.LOG_ERR,
                      "Exception in KDE frontend (invoking crash handler):")
        for line in tbtext.split('\n'):
            syslog.syslog(syslog.LOG_ERR, line)
        print >>sys.stderr, ("Exception in KDE frontend"
                             " (invoking crash handler):")
        print >>sys.stderr, tbtext

        self.post_mortem(exctype, excvalue, exctb)

        if os.path.exists('/usr/share/apport/apport-qt'):
            self.previous_excepthook(exctype, excvalue, exctb)
        else:
            dialog = QtGui.QDialog(self.ui)
            uic.loadUi("%s/crashdialog.ui" % UIDIR, dialog)
            dialog.crash_detail.setText(tbtext)
            dialog.exec_()
            sys.exit(1)

    def network_change(self, online=False):
        from PyQt4.QtCore import QTimer, SIGNAL
        if not online:
            self.set_online_state(False)
            return
        QTimer.singleShot(300, self.check_returncode)
        self.timer = QTimer(self.ui)
        self.timer.connect(self.timer, SIGNAL("timeout()"), self.check_returncode)
        self.timer.start(300)

    def check_returncode(self, *args):
        from PyQt4.QtCore import SIGNAL
        if not BaseFrontend.check_returncode(self, args):
            self.timer.disconnect(self.timer, SIGNAL("timeout()"),
                self.check_returncode)

    def set_online_state(self, state):
        for p in self.pages:
            if hasattr(p.ui, 'plugin_set_online_state'):
                p.ui.plugin_set_online_state(state)

    # Disable the KDE media notifier to avoid problems during partitioning.
    def disable_volume_manager(self):
        # FIXME, medianotifier unload port to KDE 4"
        # misc.execute('dcop', 'kded', 'kded', 'unloadModule', 'medianotifier')
        atexit.register(self.enable_volume_manager)

    def enable_volume_manager(self):
        # FIXME, medianotifier unload port to KDE 4"
        # misc.execute('dcop', 'kded', 'kded', 'loadModule', 'medianotifier')
        pass

    def run(self):
        """run the interface."""

        if os.getuid() != 0:
            title = ('This installer must be run with administrative '
                     'privileges, and cannot continue without them.')
            QtGui.QMessageBox.critical(self.ui, "Must be root", title)
            sys.exit(1)

        self.disable_volume_manager()

        self.allow_change_step(True)

        # Declare SignalHandler
        self.ui.next.clicked.connect(self.on_next_clicked)
        self.ui.back.clicked.connect(self.on_back_clicked)
        self.ui.quit.clicked.connect(self.on_quit_clicked)

        if 'UBIQUITY_AUTOMATIC' in os.environ:
            self.debconf_progress_start(0, self.pageslen,
                self.get_string('ubiquity/install/checking'))
            self.progressDialog.setWindowTitle(
                self.get_string('ubiquity/install/title'))
            self.refresh()

        # Start the interface
        self.set_current_page(0)

        while(self.pagesindex < self.pageslen):
            if self.current_page == None:
                break

            self.backup = False
            if not self.pages[self.pagesindex].filter_class:
                # This page is just a UI page
                self.dbfilter = None
                self.dbfilter_status = None
                if self.set_page(self.pages[self.pagesindex].module.NAME):
                    self.allow_change_step(True)
                    self.app.exec_()
            else:
                old_dbfilter = self.dbfilter
                if issubclass(self.pages[self.pagesindex].filter_class, Plugin):
                    ui = self.pages[self.pagesindex].ui
                else:
                    ui = None
                self.start_debconf()
                self.dbfilter = self.pages[self.pagesindex].filter_class(self, ui=ui)

                # Non-debconf steps are no longer possible as the interface is now
                # driven by whether there is a question to ask.
                if self.dbfilter is not None and self.dbfilter != old_dbfilter:
                    self.allow_change_step(False)
                    QtCore.QTimer.singleShot(0, lambda: self.dbfilter.start(auto_process=True))

                self.pages[self.pagesindex].controller.dbfilter = self.dbfilter
                self.app.exec_()
                self.pages[self.pagesindex].controller.dbfilter = None

            if self.backup or self.dbfilter_handle_status():
                if self.current_page is not None and not self.backup:
                    self.process_step()
                    if not self.stay_on_page:
                        self.pagesindex = self.pagesindex + 1
                    if 'UBIQUITY_AUTOMATIC' in os.environ:
                        # if no debconf_progress, create another one, set start to pageindex
                        self.debconf_progress_step(1)
                        self.refresh()
                if self.backup:
                    self.pagesindex = self.pop_history()

            self.app.processEvents()

        if self.current_page is not None:
            borderCSS = "border-width: 6px; border-image: " \
                        "url(/usr/share/ubiquity/qt/images/label_border.png) " \
                        "6px;"
            currentSS = "%s color: %s; " % (borderCSS, "#0088aa")
            inactiveSS = "color: %s; " % "#b3b3b3"
            for page in self.pages:
                if page.breadcrumb:
                    page.breadcrumb.setStyleSheet(inactiveSS)
            self.ui.breadcrumb_install.setStyleSheet(currentSS)
            self.start_slideshow()
            self.run_main_loop()

            quitText = '<qt>%s</qt>' % self.get_string("finished_label")
            rebootButtonText = self.get_string("reboot_button")
            shutdownButtonText = self.get_string("shutdown_button")
            quitButtonText = self.get_string("quit_button")
            titleText = self.get_string("finished_dialog")

            self.ui.hide()
            self.run_success_cmd()
            if self.oem_user_config:
                self.quit()
            elif not (self.get_reboot_seen() or self.get_shutdown_seen()):
                if ('UBIQUITY_ONLY' in os.environ or
                    'UBIQUITY_GREETER' in os.environ):
                    quitText = self.get_string('ubiquity/finished_restart_only')
                quitText = quitText.replace('${RELEASE}', misc.get_release().name)
                messageBox = QtGui.QMessageBox(QtGui.QMessageBox.Question, titleText,
                                         quitText, QtGui.QMessageBox.NoButton,
                                         self.ui)
                messageBox.addButton(rebootButtonText, QtGui.QMessageBox.AcceptRole)
                if self.show_shutdown_button:
                    messageBox.addButton(shutdownButtonText,
                                         QtGui.QMessageBox.AcceptRole)
                if ('UBIQUITY_ONLY' not in os.environ and
                    'UBIQUITY_GREETER' not in os.environ):
                    messageBox.addButton(quitButtonText, QtGui.QMessageBox.RejectRole)
                messageBox.setWindowFlags(messageBox.windowFlags() |
                                          QtCore.Qt.WindowStaysOnTopHint)
                quitAnswer = messageBox.exec_()

                if quitAnswer == 0:
                    self.reboot()
            elif self.get_reboot():
                self.reboot()
            elif self.get_shutdown():
                self.shutdown()

        return self.returncode

    def start_slideshow(self):
        slideshow_dir = '/usr/share/ubiquity-slideshow'
        slideshow_locale = self.slideshow_get_available_locale(slideshow_dir,
                                                               self.locale)
        slideshow_main = slideshow_dir + '/slides/index.html'
        if not os.path.exists(slideshow_main) or self.hide_slideshow:
            self.ui.pageMode.hide()
            return

        slides = 'file://' + slideshow_main
        if slideshow_locale != 'c': #slideshow will use default automatically
            slides += '#?locale=' + slideshow_locale
            ltr = i18n.get_string('default-ltr', slideshow_locale,
                                  'ubiquity/imported')
            if ltr == 'default:RTL':
                slides += '?rtl'

        from PyQt4.QtWebKit import QWebView
        from PyQt4.QtWebKit import QWebPage
        def openLink(qUrl):
            QtGui.QDesktopServices.openUrl(qUrl)

        webView = QWebView()
        webView.linkClicked.connect(openLink)
        webView.setContextMenuPolicy(QtCore.Qt.NoContextMenu)
        webView.page().setLinkDelegationPolicy(QWebPage.DelegateExternalLinks)
        webView.page().mainFrame().setScrollBarPolicy(QtCore.Qt.Horizontal,
                                                      QtCore.Qt.ScrollBarAlwaysOff)
        webView.page().mainFrame().setScrollBarPolicy(QtCore.Qt.Vertical,
                                                      QtCore.Qt.ScrollBarAlwaysOff)
        webView.setFixedSize(700,420)
        webView.load(QtCore.QUrl(slides))

        self.ui.pageMode.setCurrentIndex(1)
        self.ui.pageMode.widget(1).layout().addWidget(webView)
        webView.show()

    def set_layout_direction(self, lang=None):
        if not lang:
            lang = self.locale
        # TODO: At the moment we have to special-case languages. This will
        # be easier to fix when we move to cdebconf and have the
        # debconf/text-direction template easily available.
        if lang.startswith('ar') or lang.startswith('he'):
            direction = QtCore.Qt.RightToLeft
        else:
            direction = QtCore.Qt.LeftToRight
        self.app.setLayoutDirection(direction)

    def all_children(self, parentWidget=None):
        if parentWidget is None:
            parentWidget = self.ui

        def recurse(x, y):
            return x + self.all_children(y)
        rv = reduce(recurse, parentWidget.children(), [parentWidget])
        return rv

    def translate_pages(self, lang=None, just_current=True, not_current=False, reget=False):
        current_page = self.pages[self.pagesindex]
        if just_current:
            pages = [self.pages[self.pagesindex]]
        else:
            pages = self.pages
        widgets = []
        for p in pages:
            # There's no sense retranslating the page we're leaving.
            if not_current and p == current_page:
                continue
            prefix = p.ui.get('plugin_prefix')
            for w in p.widgets:
                for c in self.all_children(w):
                    widgets.append((c, prefix))

        #if not just_current:
        #for toplevel in self.toplevels:
            #if toplevel.name != 'live_installer':
                #for c in self.all_children(toplevel):
                    #widgets.append((c, None))
        self.translate_widgets(lang=lang, widgets=widgets, reget=reget)
        # Allow plugins to provide a hook for translation.
        for p in pages:
            # There's no sense retranslating the page we're leaving.
            if not_current and p == current_page:
                continue
            if hasattr(p.ui, 'plugin_translate'):
                try:
                    p.ui.plugin_translate(lang or self.locale)
                except Exception, e:
                    print >>sys.stderr, 'Could not translate page (%s): %s' \
                                        % (p.module.NAME, str(e))

    # translates widget text based on the object names
    # widgets is a list of (widget, prefix) pairs
    def translate_widgets(self, lang=None, widgets=None, reget=True):
        if lang is None:
            lang = self.locale
        if lang is None:
            languages = []
        else:
            languages = [lang]
        if widgets is None:
            widgets = [(x, None) for x in self.all_children()]

        if reget:
            core_names = ['ubiquity/text/%s' % q for q in self.language_questions]
            core_names.append('ubiquity/text/oem_config_title')
            core_names.append('ubiquity/text/oem_user_config_title')
            core_names.append('ubiquity/text/breadcrumb_install')
            core_names.append('ubiquity/text/release_notes_only')
            core_names.append('ubiquity/text/update_installer_only')
            core_names.append('ubiquity/text/USB')
            core_names.append('ubiquity/text/CD')
            for stock_item in ('cancel', 'close', 'go-back', 'go-forward',
                               'ok', 'quit', 'yes', 'no'):
                core_names.append('ubiquity/imported/%s' % stock_item)
            prefixes = []
            for p in self.pages:
                prefix = p.ui.get('plugin_prefix')
                if not prefix:
                    prefix = 'ubiquity/text'
                if p.ui.get('plugin_is_language'):
                    children = reduce(lambda x,y: x + self.all_children(y), p.widgets, [])
                    core_names.extend([prefix+'/'+c.objectName() for c in children])
                if p.breadcrumb_question:
                    core_names.append(p.breadcrumb_question)
                prefixes.append(prefix)
            i18n.get_translations(languages=languages, core_names=core_names, extra_prefixes=prefixes)

        # We always translate always-visible widgets
        for q in self.language_questions:
            if hasattr(self.ui, q):
                widgets.append((getattr(self.ui, q), None))
            elif q == 'live_installer':
                widgets.append((self.ui, None))
        widgets.extend([(x, None) for x in self.all_children(self.ui.steps_widget)])

        for w in widgets:
            self.translate_widget(w[0], lang=lang, prefix=w[1])

        self.set_layout_direction()

    def translate_widget_children(self, parentWidget):
        for w in self.all_children(parentWidget):
            self.translate_widget(w)

    def translate_widget(self, widget, lang=None, prefix=None):
        if lang is None:
            lang = self.locale
        #FIXME needs translations for Next, Back and Cancel
        if not isinstance(widget, QtGui.QWidget):
            return

        name = str(widget.objectName())

        text = self.get_string(name, lang, prefix)

        if str(name) == "UbiquityUIBase":
            text = self.get_string("live_installer", lang, prefix)

        if text is None:
            return

        if isinstance(widget, QtGui.QLabel):
            if name == 'select_language_label' and self.oem_user_config:
                text = self.get_string('select_language_oem_user_label', lang, prefix)

            if 'heading_label' in name:
                widget.setText("<h2>" + text + "</h2>")
            elif 'extra_label' in name:
                widget.setText("<small>" + text + "</small>")
            elif ('group_label' in name or 'warning_label' in name or
                  name in ('drives_label', 'partition_method_label')):
                widget.setText("<strong>" + text + "</strong>")
            else:
                widget.setText(text)

        elif isinstance(widget, QtGui.QAbstractButton):
            widget.setText(text.replace('_', '&', 1))

        elif isinstance(widget, QtGui.QWidget) and str(name) == "UbiquityUIBase":
            if self.custom_title:
                text = self.custom_title
            elif self.oem_config:
                text = self.get_string('oem_config_title', lang, prefix)
            elif self.oem_user_config:
                text = self.get_string('oem_user_config_title', lang, prefix)
            widget.setWindowTitle(text)

        else:
            print "WARNING: unknown widget: " + name
            print "Type: ", type(widget)

    def allow_change_step(self, allowed):
        if allowed:
            cursor = QtGui.QCursor(QtCore.Qt.ArrowCursor)
        else:
            cursor = QtGui.QCursor(QtCore.Qt.WaitCursor)
        self.ui.setCursor(cursor)
        self.ui.back.setEnabled(allowed and self.allowed_go_backward)
        self.ui.next.setEnabled(allowed and self.allowed_go_forward)
        self.allowed_change_step = allowed

    def allow_go_backward(self, allowed):
        self.ui.back.setEnabled(allowed and self.allowed_change_step)
        self.allowed_go_backward = allowed

    def allow_go_forward(self, allowed):
        self.ui.next.setEnabled(allowed and self.allowed_change_step)
        self.allowed_go_forward = allowed

    def dbfilter_handle_status(self):
        """If a dbfilter crashed, ask the user if they want to continue anyway.

        Returns True to continue, or False to try again."""

        if not self.dbfilter_status or self.current_page is None:
            return True

        syslog.syslog('dbfilter_handle_status: %s' % str(self.dbfilter_status))

        # TODO cjwatson 2007-04-04: i18n
        text = ('%s failed with exit code %s. Further information may be '
                'found in /var/log/syslog. Do you want to try running this '
                'step again before continuing? If you do not, your '
                'installation may fail entirely or may be broken.' %
                (self.dbfilter_status[0], self.dbfilter_status[1]))
        #FIXME QMessageBox seems to have lost the ability to set custom labels
        # so for now we have to get by with these not-entirely meaningful stock labels
        answer = QtGui.QMessageBox.warning(self.ui,
                                     '%s crashed' % self.dbfilter_status[0],
                                     text, QtGui.QMessageBox.Retry,
                                     QtGui.QMessageBox.Ignore,
                                     QtGui.QMessageBox.Close)
        self.dbfilter_status = None
        syslog.syslog('dbfilter_handle_status: answer %d' % answer)
        if answer == QtGui.QMessageBox.Ignore:
            return True
        elif answer == QtGui.QMessageBox.Close:
            self.quit()
        else:
            step = self.step_name(self.get_current_page())
            if str(step) == "partman":
                self.set_current_page(self.step_index("stepPartAuto"))
            return False

    def step_name(self, step_index):
        if step_index < 0:
            step_index = 0
        return str(self.stackLayout.widget(step_index).objectName())

    def step_index(self, step_name):
        if hasattr(self.ui, step_name):
            step = getattr(self.ui, step_name)
            return self.stackLayout.indexOf(step)
        else:
            return 0

    def set_page(self, n):
        self.run_automation_error_cmd()
        self.ui.show()

        borderCSS = "border-width: 6px; border-image: url(/usr/share/ubiquity/qt/images/label_border.png) 6px;"
        activeSS = "color: %s; " % "#666666"
        inactiveSS = "color: %s; " % "#b3b3b3"
        currentSS = "%s color: %s; " % (borderCSS, "#0088aa")

        #set all the steps active
        #each step will set its previous ones as inactive
        #this handles the ability to go back

        found = False
        is_install = False
        for page in self.pages:
            if page.module.NAME == n:
                # Now ask ui class which page we want to be showing right now
                if hasattr(page.ui, 'plugin_get_current_page'):
                    cur = page.ui.call('plugin_get_current_page')
                    if isinstance(cur, str) and hasattr(self.ui, cur):
                        cur = getattr(self.ui, cur) # for not-yet-plugins
                elif page.widgets:
                    cur = page.widgets[0]
                if not cur:
                    return False
                index = self.stackLayout.indexOf(cur)
                self.add_history(page, cur)
                self.set_current_page(index)
                if page.breadcrumb:
                    page.breadcrumb.setStyleSheet(currentSS)
                found = True
                is_install = page.ui.get('plugin_is_install')
            elif page.breadcrumb:
                if found:
                    page.breadcrumb.setStyleSheet(activeSS)
                else:
                    page.breadcrumb.setStyleSheet(inactiveSS)
        self.ui.breadcrumb_install.setStyleSheet(activeSS)

        if is_install:
            self.ui.next.setText(
                self.get_string('install_button').replace('_', '&', 1))
            self.ui.next.setIcon(self.applyIcon)
        else:
            self.ui.next.setText(self.get_string("next").replace('_', '&', 1))
            self.ui.next.setIcon(self.forwardIcon)
            self.translate_widget(self.ui.next)

        if self.pagesindex == 0:
            self.allow_go_backward(False)
        elif self.pages[self.pagesindex - 1].module.NAME == 'partman':
            # We're past partitioning.  Unless the install fails, there is no
            # going back.
            self.allow_go_backward(False)
            self.ui.quit.hide()
        else:
            self.allow_go_backward(True)

        return True

    def page_name(self, step_index):
        if step_index < 0:
            step_index = 0
        return str(self.stackLayout.widget(step_index).objectName())

    def set_current_page(self, current):
        widget = self.stackLayout.widget(current)
        if self.stackLayout.currentWidget() == widget:
            # self.ui.widgetStack.raiseWidget() will do nothing.
            # Update state ourselves.
            self.on_steps_switch_page(current)
        else:
            self.stackLayout.setCurrentWidget(widget)
            self.on_steps_switch_page(current)

    def reboot(self, *args):
        """reboot the system after installing process."""
        self.returncode = 10
        self.quit()
    def shutdown(self, *args):
        """Shutdown the system after installing process."""

        self.returncode = 11
        self.quit()
    def do_reboot(self):
        """Callback for main program to actually reboot the machine."""
        try:
            session = dbus.Bus.get_session()
            ksmserver = session.name_has_owner('org.kde.ksmserver')
        except dbus.exceptions.DBusException:
            ksmserver = False
        if ksmserver:
            ksmserver = session.get_object('org.kde.ksmserver', '/KSMServer')
            ksmserver = dbus.Interface(ksmserver, 'org.kde.KSMServerInterface')
            # ShutdownConfirmNo, ShutdownTypeReboot, ShutdownModeForceNow
            ksmserver.logout(0, 1, 2)
        else:
            misc.execute_root('reboot')

    def do_shutdown(self):
        """Callback for main program to actually shutdown the machine."""
        try:
            session = dbus.Bus.get_session()
            ksmserver = session.name_has_owner('org.kde.ksmserver')
        except dbus.exceptions.DBusException:
            ksmserver = False
        if ksmserver:
            ksmserver = session.get_object('org.kde.ksmserver', '/KSMServer')
            ksmserver = dbus.Interface(ksmserver, 'org.kde.KSMServerInterface')
            # ShutdownConfirmNo, ShutdownTypeReboot, ShutdownModeForceNow
            ksmserver.logout(0, 2, 2)
        else:
            misc.execute_root('poweroff')


    def quit(self):
        """quit installer cleanly."""
        self.current_page = None
        if self.dbfilter is not None:
            self.dbfilter.cancel_handler()

        self.app.exit()

    def quit_installer(self):
        """quit installer cleanly."""

        # exiting from application
        self.current_page = None
        if self.dbfilter is not None:
            self.dbfilter.cancel_handler()
        self.quit_main_loop()

    def on_quit_clicked(self):
        warning_dialog_label = self.get_string("warning_dialog_label")
        abortTitle = self.get_string("warning_dialog")
        yes = self.get_string('yes', prefix='ubiquity/imported')
        no = self.get_string('no', prefix='ubiquity/imported')
        messageBox = QtGui.QMessageBox()
        messageBox.setWindowTitle(abortTitle)
        messageBox.setText(warning_dialog_label)
        messageBox.setStandardButtons(QtGui.QMessageBox.Yes |
                                                          QtGui.QMessageBox.No)
        messageBox.setDefaultButton(QtGui.QMessageBox.Yes)
        messageBox.button(QtGui.QMessageBox.Yes).setText(
                                                      yes.replace('_', '&', 1))
        messageBox.button(QtGui.QMessageBox.No).setText(
                                                       no.replace('_', '&', 1))
        response = messageBox.exec_()
        if response == QtGui.QMessageBox.Yes:
            self.current_page = None
            self.quit()
            return True
        else:
            return False

    def on_next_clicked(self):
        """Callback to control the installation process between steps."""
        if not self.allowed_change_step or not self.allowed_go_forward:
            return

        self.allow_change_step(False)

        if self.dbfilter is not None:
            self.dbfilter.ok_handler()
            # expect recursive main loops to be exited and
            # debconffilter_done() to be called when the filter exits
        else:
            self.app.exit()

    def process_step(self):
        """Process and validate the results of this step."""

        # setting actual step
        step_num = self.get_current_page()
        step = self.page_name(step_num)
        syslog.syslog('Step_before = %s' % step)

        if step.startswith("stepPart"):
            self.previous_partitioning_page = step_num

        # Automatic partitioning
        if step == "stepPartAuto":
            self.process_autopartitioning()

    def process_autopartitioning(self):
        """Processing automatic partitioning step tasks."""
        self.app.processEvents()

        # For safety, if we somehow ended up improperly initialised
        # then go to manual partitioning.
        choice = self.get_autopartition_choice()[0]
        if self.manual_choice is None or choice == self.manual_choice:
            self.set_current_page(self.step_index("stepPartAdvanced"))
        else:
            self.set_current_page(self.step_index("stepUserInfo"))

    def on_back_clicked(self):
        """Callback to set previous screen."""
        if not self.allowed_change_step:
            return

        self.allow_change_step(False)

        self.backup = True
        self.stay_on_page = False

        # Enabling next button
        self.allow_go_forward(True)
        self.ui.setCursor(QtGui.QCursor(QtCore.Qt.WaitCursor))

        if self.dbfilter is not None:
            self.dbfilter.cancel_handler()
            # expect recursive main loops to be exited and
            # debconffilter_done() to be called when the filter exits
        else:
            self.app.exit()

    def on_steps_switch_page(self, newPageID):
        self.ui.content_widget.show()
        self.current_page = newPageID
        name = self.step_name(newPageID)
        syslog.syslog('switched to page %s' % name)
        if 'UBIQUITY_GREETER' in os.environ:
            if name == 'language':
                self.ui.steps_widget.hide()
                self.ui.navigation.hide()
            else:
                self.ui.steps_widget.show()
                self.ui.navigation.show()
        else:
            self.ui.steps_widget.show()
            self.ui.navigation.show()

    def watch_debconf_fd (self, from_debconf, process_input):
        if from_debconf in self.debconf_callbacks:
            self.watch_debconf_fd_helper_disconnect(from_debconf)
        self.socketNotifierRead[from_debconf] = QtCore.QSocketNotifier(from_debconf, QtCore.QSocketNotifier.Read, self.app)
        self.socketNotifierRead[from_debconf].activated[int].connect(self.watch_debconf_fd_helper_read)

        self.socketNotifierWrite[from_debconf] = QtCore.QSocketNotifier(from_debconf, QtCore.QSocketNotifier.Write, self.app)
        self.socketNotifierWrite[from_debconf].activated[int].connect(self.watch_debconf_fd_helper_write)

        self.socketNotifierException[from_debconf] = QtCore.QSocketNotifier(from_debconf, QtCore.QSocketNotifier.Exception, self.app)
        self.socketNotifierException[from_debconf].activated[int].connect(self.watch_debconf_fd_helper_exception)

        self.debconf_callbacks[from_debconf] = process_input

    def watch_debconf_fd_helper_disconnect (self, source):
        del self.debconf_callbacks[source]
        self.socketNotifierRead[source].activated[int].disconnect(self.watch_debconf_fd_helper_read)
        self.socketNotifierWrite[source].activated[int].disconnect(self.watch_debconf_fd_helper_write)
        self.socketNotifierException[source].activated[int].disconnect(self.watch_debconf_fd_helper_exception)
        del self.socketNotifierRead[source]
        del self.socketNotifierWrite[source]
        del self.socketNotifierException[source]

    def watch_debconf_fd_helper_read (self, source):
        debconf_condition = 0
        debconf_condition |= filteredcommand.DEBCONF_IO_IN
        callback = self.debconf_callbacks[source]
        if not callback(source, debconf_condition):
            # The parallel dbfilter code in debconffilter_done could re-open
            # this fd before we reach this point.
            if callback == self.debconf_callbacks[source]:
                self.watch_debconf_fd_helper_disconnect(source)

    def watch_debconf_fd_helper_write(self, source):
        debconf_condition = 0
        debconf_condition |= filteredcommand.DEBCONF_IO_OUT
        callback = self.debconf_callbacks[source]
        if not callback(source, debconf_condition):
            if callback == self.debconf_callbacks[source]:
                self.watch_debconf_fd_helper_disconnect(source)

    def watch_debconf_fd_helper_exception(self, source):
        debconf_condition = 0
        debconf_condition |= filteredcommand.DEBCONF_IO_ERR
        callback = self.debconf_callbacks[source]
        if not callback(source, debconf_condition):
            if callback == self.debconf_callbacks[source]:
                self.watch_debconf_fd_helper_disconnect(source)

    def debconf_progress_start (self, progress_min, progress_max, progress_title):
        self.progress_position.start(progress_min, progress_max,
                                     progress_title)
        self.debconf_progress_set(0)
        self.debconf_progress_info(progress_title)
        total_steps = progress_max - progress_min
        self.ui.progressBar.setMaximum(total_steps)
        self.ui.progressBar.setFormat(progress_title + " %p%")

    def debconf_progress_set (self, progress_val):
        self.progress_cancelled = self.progressDialog.wasCanceled()
        if self.progress_cancelled:
            return False
        self.progress_position.set(progress_val)
        fraction = self.progress_position.fraction()

        self.ui.progressBar.setValue(int(fraction * self.ui.progressBar.maximum()))

        return True

    def debconf_progress_step (self, progress_inc):
        self.progress_cancelled = self.progressDialog.wasCanceled()
        if self.progress_cancelled:
            return False
        self.progress_position.step(progress_inc)
        fraction = self.progress_position.fraction()

        self.ui.progressBar.setValue(int(fraction * self.ui.progressBar.maximum()))

        return True

    def debconf_progress_info (self, progress_info):
        self.progress_cancelled = self.progressDialog.wasCanceled()
        if self.progress_cancelled:
            return False

        self.ui.progressBar.setFormat(progress_info + " %p%")

        return True

    def debconf_progress_stop (self):
        self.progress_cancelled = False
        self.progress_position.stop()

    def debconf_progress_region (self, region_start, region_end):
        self.progress_position.set_region(region_start, region_end)

    def debconf_progress_cancellable (self, cancellable):
        if cancellable:
            self.progressDialog.setCancellable(True)
            self.ui.progressCancel.show()
        else:
            self.ui.progressCancel.hide()
            self.progressDialog.setCancellable(False)
            self.progress_cancelled = False

    #def on_progress_cancel_button_clicked (self, button):
    #    self.progress_cancelled = True

    def debconffilter_done (self, dbfilter):
        # processing events here prevents GUI from hanging until mouse moves
        # (LP #556376)
        self.app.processEvents()
        if not dbfilter.status:
            self.find_next_step(dbfilter.__module__)
        elif dbfilter.__module__ in ('ubiquity.components.install',
                                     'ubiquity.components.plugininstall'):
            # We don't want to try to retry a failing step here, because it
            # will have the same set of inputs, and thus likely the same
            # result.
            # TODO: We may want to call return_to_partitioning after the crash
            # dialog instead.
            dialog = QtGui.QDialog(self.ui)
            uic.loadUi("%s/crashdialog.ui" % UIDIR, dialog)
            dialog.exec_()
            sys.exit(1)
        if BaseFrontend.debconffilter_done(self, dbfilter):
            self.app.exit()
            return True
        else:
            return False

    def find_next_step(self, finished_step):
        # TODO need to handle the case where debconffilters launched from
        # here crash.  Factor code out of dbfilter_handle_status.
        last_page = self.pages[-1].module.__name__
        if finished_step == last_page and not self.backup:
            self.finished_pages = True
            if self.finished_installing or self.oem_user_config:
                self.debconf_progress_info('')
                self.ui.progressBar.show()
                dbfilter = plugininstall.Install(self)
                dbfilter.start(auto_process=True)

        elif finished_step == 'ubi-partman':
            # Flush changes to the database so that when the parallel db
            # starts, it does so with the most recent changes.
            self.stop_debconf()
            self.start_debconf()
            self.ui.progressBar.show()
            self.installing = True
            from ubiquity.debconfcommunicator import DebconfCommunicator
            if self.parallel_db is not None:
                # Partitioning failed and we're coming back through again.
                self.parallel_db.shutdown()
            env = os.environ.copy()
            # debconf-apt-progress, start_debconf()
            env['DEBCONF_DB_REPLACE'] = 'configdb'
            env['DEBCONF_DB_OVERRIDE'] = 'Pipe{infd:none outfd:none}'
            self.parallel_db = DebconfCommunicator('ubiquity', cloexec=True,
                                                   env=env)
            dbfilter = partman_commit.PartmanCommit(self, db=self.parallel_db)
            dbfilter.start(auto_process=True)

        # FIXME OH DEAR LORD.  Use isinstance.
        elif finished_step == 'ubiquity.components.partman_commit':
            dbfilter = install.Install(self, db=self.parallel_db)
            dbfilter.start(auto_process=True)

        elif finished_step == 'ubiquity.components.install':
            self.finished_installing = True
            if self.finished_pages:
                dbfilter = plugininstall.Install(self)
                dbfilter.start(auto_process=True)
            else:
                self.ui.progressBar.hide()

        elif finished_step == 'ubiquity.components.plugininstall':
            self.installing = False
            self.quit_main_loop()

    def installation_medium_mounted (self, message):
        self.ui.part_advanced_warning_message.setText(message)
        self.ui.part_advanced_warning_hbox.show()

    def return_to_partitioning (self):
        """If the install progress bar is up but still at the partitioning
        stage, then errors can safely return us to partitioning.
        """
        if self.installing and not self.installing_no_return:
            # Stop the currently displayed page.
            if self.dbfilter is not None:
                self.dbfilter.cancel_handler()
            # Go back to the partitioner and try again.
            self.pagesindex = -1
            for page in self.pages:
                if page.module.NAME == 'partman':
                    self.pagesindex = self.pages.index(page)
                    break
            if self.pagesindex == -1: return
            self.start_debconf()
            ui = self.pages[self.pagesindex].ui
            self.dbfilter = self.pages[self.pagesindex].filter_class(self, ui=ui)
            self.allow_change_step(False)
            self.dbfilter.start(auto_process=True)
            self.ui.next.setText(self.get_string("next").replace('_', '&', 1))
            self.ui.next.setIcon(self.forwardIcon)
            self.translate_widget(self.ui.next)
            self.installing = False
            self.ui.progressBar.hide()
            self.ui.quit.show()

    def error_dialog (self, title, msg, fatal=True):
        self.run_automation_error_cmd()
        # TODO cjwatson 2009-04-16: We need to call allow_change_step here
        # to get a normal cursor, but that also enables the Back/Forward
        # buttons. Cursor handling should be controllable independently.
        saved_allowed_change_step = self.allowed_change_step
        self.allow_change_step(True)
        # TODO: cancel button as well if capb backup
        QtGui.QMessageBox.warning(self.ui, title, msg, QtGui.QMessageBox.Ok)
        self.allow_change_step(saved_allowed_change_step)
        if fatal:
            self.return_to_partitioning()

    def question_dialog (self, title, msg, options, use_templates=True):
        self.run_automation_error_cmd()
        # I doubt we'll ever need more than three buttons.
        assert len(options) <= 3, options

        # TODO cjwatson 2009-04-16: We need to call allow_change_step here
        # to get a normal cursor, but that also enables the Back/Forward
        # buttons. Cursor handling should be controllable independently.
        saved_allowed_change_step = self.allowed_change_step
        self.allow_change_step(True)
        buttons = {}
        messageBox = QtGui.QMessageBox(QtGui.QMessageBox.Question, title, msg,
                                       QtGui.QMessageBox.NoButton, self.ui)
        for option in options:
            if use_templates:
                text = self.get_string(option)
            else:
                text = option
            if text is None:
                text = option
            text = text.replace("_", "&")
            # Convention for options is to have the affirmative action last; KDE
            # convention is to have it first.
            if option == options[-1]:
                button = messageBox.addButton(text, QtGui.QMessageBox.AcceptRole)
            else:
                button = messageBox.addButton(text, QtGui.QMessageBox.RejectRole)
            buttons[button] = option

        response = messageBox.exec_()
        self.allow_change_step(saved_allowed_change_step)

        if response < 0:
            return None
        else:
            return buttons[messageBox.clickedButton()]

    def refresh (self):
        self.app.processEvents()

    # Run the UI's main loop until it returns control to us.
    def run_main_loop (self):
        self.allow_change_step(True)
        self.mainLoopRunning = True
        while self.mainLoopRunning:  # nasty, but works OK
            self.app.processEvents(QtCore.QEventLoop.WaitForMoreEvents)

    # Return control to the next level up.
    def quit_main_loop (self):
        self.mainLoopRunning = False

    # returns the current wizard page
    def get_current_page(self):
        return self.stackLayout.indexOf(self.stackLayout.currentWidget())
