#!/usr/bin/python3
# -*- coding: utf-8 -*-
""" Onboard preferences utility """

from __future__ import division, print_function, unicode_literals

import os
import sys
import copy
import shutil
from subprocess import Popen
from xml.parsers.expat import ExpatError
from xml.dom import minidom
import gettext
try:
    import dbus.mainloop.glib
except ImportError:
    pass

from gi.repository import GObject, Pango, Gdk, Gtk

# install translation function _() for all modules
from Onboard.LayoutLoaderSVG import LayoutLoaderSVG
from Onboard.SnippetView     import SnippetView
from Onboard.Appearance      import Theme, ColorScheme
from Onboard.Scanner         import ScanMode, ScanDevice
from Onboard.XInput          import XIDeviceManager, XIEventType
from Onboard.utils           import show_ask_string_dialog, \
                                    show_confirmation_dialog, \
                                    unicode_str, open_utf8

app = "onboard"

### Logging ###
import logging
_logger = logging.getLogger("Settings")
###############

### Config Singleton ###
from Onboard.Config import Config, NumResizeHandles
config = Config()
########################


def LoadUI(filebase):
    builder = Gtk.Builder()
    builder.set_translation_domain(app)
    builder.add_from_file(os.path.join(config.install_dir, filebase+".ui"))
    return builder

def format_list_item(text, issystem):
    if issystem:
        return "<i>{0}</i>".format(text)
    return text


class DialogBuilder(object):
    """
    Utility class for simplified widget setup.
    Has helpers for connecting widgets to ConfigObject properties, i.e.
    indirectly to gsettings keys.
    Mostly borrowed from Gerd Kohlberger's ScannerDialog.
    """

    def __init__(self, builder):
        self._builder = builder

    def wid(self, name):
        widget = self._builder.get_object(name)
        assert(widget)
        return widget

    # push button
    def bind_button(self, name, callback):
        w = self.wid(name)
        w.connect("clicked", callback)

    # spin button
    def bind_spin(self, name, config_object, key):
        w = self.wid(name)
        w.set_value(getattr(config_object, key))
        w.connect("value-changed", self.bind_spin_callback, config_object, key)
        getattr(config_object, key + '_notify_add')(w.set_value)

    def bind_spin_callback(self, widget, config_object, key):
        setattr(config_object, key, widget.get_value())

    # scale
    def bind_scale(self, name, config_object, key, widget_callback = None):
        w = self.wid(name)
        w.set_value(getattr(config_object, key))
        w.connect("value-changed", self.bind_scale_callback,
                          config_object, key, widget_callback)
        getattr(config_object, key + '_notify_add')(w.set_value)

    def bind_scale_callback(self, widget, config_object, key, callback):
        value = widget.get_value()
        setattr(config_object, key, value)
        if callback:
            callback(value)

    # checkbox
    def bind_check(self, name, config_object, key,
                   config_get_callback = None, config_set_callback = None):
        w = self.wid(name)
        if config_get_callback:
            active = config_get_callback(config_object, key)
        else:
            active = getattr(config_object, key)
        w.set_active(active)
        w.connect("toggled", self._bind_check_callback,
                  config_object, key, config_set_callback)
        getattr(config_object, key + '_notify_add')( \
             lambda x: self._notify_check_callback(w, config_object, key,
                                                     config_get_callback))

    def _notify_check_callback(self, widget, config_object,
                              key, config_get_callback):
        if config_get_callback:
            active = config_get_callback(config_object, key)
        else:
            active = getattr(config_object, key)
        widget.set_active(active)

    def _bind_check_callback(self, widget, config_object,
                            key, config_set_callback):
        if config_set_callback:
            config_set_callback(config_object, key, widget.get_active())
        else:
            setattr(config_object, key, widget.get_active())

    # combobox with id column
    def bind_combobox_id(self, name, config_object, key,
                         config_get_callback = None, config_set_callback = None):
        w = self.wid(name)
        if config_get_callback:
            id = config_get_callback(config_object, key)
        else:
            id = str(getattr(config_object, key))
        w.set_active_id(id)
        w.connect("changed", self.bind_combobox_callback,
                  config_object, key, config_set_callback)
        notify_callback = lambda x : w.set_active_id(str(x))
        getattr(config_object, key + '_notify_add')( \
             lambda x: self.notify_combobox_callback(w, config_object, key,
                                                     config_get_callback))
    def notify_combobox_callback(self, widget,
                                 config_object, key, config_get_callback):
        if config_get_callback:
            id = config_get_callback(config_object, key)
        else:
            id = str(getattr(config_object, key))
        widget.set_active_id(id)

    def bind_combobox_callback(self, widget,
                               config_object, key, config_set_callback):
        if config_set_callback:
            config_set_callback(config_object, key, widget.get_active_id())
        else:
            id = widget.get_active_id()
            assert(not id is None)  # make sure ID-Column is 0
            if not id is None:
                setattr(config_object, key, int(widget.get_active_id()))

    def select_tree_view_row(self, view, column, value, _it = None):
        model = view.get_model()
        if _it is None:
            _it = model.get_iter_first()
        while _it:
            child_it = model.iter_children(_it)
            if child_it:
                self.select_tree_view_row(view, column, value, child_it)

            fn = model.get_value(_it, column)
            if fn == value:
                sel = view.get_selection()
                if sel:
                    sel.select_iter(_it)

            _it = model.iter_next(_it)


class Settings(DialogBuilder):

    # column ids of the layout view
    LAYOUT_COL_NAME = 0
    LAYOUT_COL_SUMMARY = 1
    LAYOUT_COL_FILENAME = 2
    LAYOUT_COL_HAS_ABOUT_INFO = 3
    LAYOUT_COL_IS_ROW_SENSITIVE = 4


    def __init__(self,mainwin):
        self.themes = {}       # cache of theme objects

        # Use D-bus main loop by default
        if "dbus" in globals():
            dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
        else:
            _logger.warning("D-Bus bindings unavailable.")

        # finish config initialization
        config.init()

        # init dialog builder
        builder = LoadUI("settings")
        DialogBuilder.__init__(self, builder)

        self.window = builder.get_object("settings_window")
        Gtk.Window.set_default_icon_name("onboard")
        self.window.set_title(_("Onboard Preferences"))

        # General tab
        self.status_icon_toggle = builder.get_object("status_icon_toggle")
        self.status_icon_toggle.set_active(config.show_status_icon)
        config.show_status_icon_notify_add(self.status_icon_toggle.set_active)

        self.start_minimized_toggle = builder.get_object(
            "start_minimized_toggle")
        self.start_minimized_toggle.set_active(config.start_minimized)
        config.start_minimized_notify_add(
            self.start_minimized_toggle.set_active)

        self.icon_palette_toggle = builder.get_object("icon_palette_toggle")
        self.icon_palette_toggle.set_active(config.icp.in_use)
        config.icp.in_use_notify_add(self.icon_palette_toggle.set_active)

        #self.modeless_gksu_toggle = builder.get_object("modeless_gksu_toggle")
        #self.modeless_gksu_toggle.set_active(config.modeless_gksu)
        #config.modeless_gksu_notify_add(self.modeless_gksu_toggle.set_active)

        self.onboard_xembed_toggle = builder.get_object("onboard_xembed_toggle")
        self.onboard_xembed_toggle.set_active(config.onboard_xembed_enabled)
        config.onboard_xembed_enabled_notify_add( \
                self.onboard_xembed_toggle.set_active)

        self.show_tooltips_toggle = builder.get_object("show_tooltips_toggle")
        self.show_tooltips_toggle.set_active(config.show_tooltips)
        config.show_tooltips_notify_add(self.show_tooltips_toggle.set_active)

        self.auto_show_toggle = builder.get_object("auto_show_toggle")
        self.auto_show_toggle.set_active(config.auto_show.enabled)
        config.auto_show.enabled_notify_add(self.auto_show_toggle.set_active)

        # window tab
        self.window_decoration_toggle = \
                              builder.get_object("window_decoration_toggle")
        self.window_decoration_toggle.set_active(config.window.window_decoration)
        config.window.window_decoration_notify_add(lambda x:
                                    [self.window_decoration_toggle.set_active(x),
                                     self.update_window_widgets()])

        self.window_state_sticky_toggle = \
                             builder.get_object("window_state_sticky_toggle")
        self.window_state_sticky_toggle.set_active( \
                                             config.window.window_state_sticky)
        config.window.window_state_sticky_notify_add( \
                                    self.window_state_sticky_toggle.set_active)

        self.force_to_top_toggle = builder.get_object("force_to_top_toggle")
        self.force_to_top_toggle.set_active(config.is_force_to_top())
        config.window.force_to_top_notify_add(lambda x: \
                                       [self.force_to_top_toggle.set_active(x),
                                        self.update_window_widgets()])

        self.keep_aspect_ratio_toggle = builder.get_object(
            "keep_aspect_ratio_toggle")
        self.keep_aspect_ratio_toggle.set_active(config.window.keep_aspect_ratio)
        config.window.keep_aspect_ratio_notify_add(
            self.keep_aspect_ratio_toggle.set_active)

        self.transparent_background_toggle = \
                         builder.get_object("transparent_background_toggle")
        self.transparent_background_toggle.set_active(config.window.transparent_background)
        config.window.transparent_background_notify_add(lambda x:
                            [self.transparent_background_toggle.set_active(x),
                             self.update_window_widgets()])

        self.transparency_spinbutton = builder.get_object("transparency_spinbutton")
        self.transparency_spinbutton.set_value(config.window.transparency)
        config.window.transparency_notify_add(self.transparency_spinbutton.set_value)

        self.background_transparency_spinbutton = \
                           builder.get_object("background_transparency_spinbutton")
        self.background_transparency_spinbutton.set_value(config.window.background_transparency)
        config.window.background_transparency_notify_add(self.background_transparency_spinbutton.set_value)

        self.inactivity_frame = builder.get_object("inactive_behavior_frame")

        self.enable_inactive_transparency_toggle = \
                    builder.get_object("enable_inactive_transparency_toggle")
        self.enable_inactive_transparency_toggle.set_active( \
                                        config.window.enable_inactive_transparency)
        config.window.enable_inactive_transparency_notify_add(lambda x: \
                            [self.enable_inactive_transparency_toggle.set_active(x),
                             self.update_window_widgets()])

        self.inactive_transparency_spinbutton = \
                             builder.get_object("inactive_transparency_spinbutton")
        self.inactive_transparency_spinbutton.set_value(config.window.inactive_transparency)
        config.window.inactive_transparency_notify_add(self.inactive_transparency_spinbutton.set_value)

        self.inactive_transparency_delay_spinbutton = \
                             builder.get_object("inactive_transparency_delay_spinbutton")
        self.inactive_transparency_delay_spinbutton.set_value(config.window.inactive_transparency_delay)
        config.window.inactive_transparency_delay_notify_add(self.inactive_transparency_delay_spinbutton.set_value)

        # Keyboard - first page
        self.bind_check("touch_feedback_enabled_toggle",
                        config.keyboard, "touch_feedback_enabled")
        self.bind_check("audio_feedback_enabled_toggle",
                        config.keyboard, "audio_feedback_enabled")
        self.bind_check("show_secondary_labels_toggle",
                        config.keyboard, "show_secondary_labels")

        # Keyboard - Advanced page
        self.bind_combobox_id("default_key_action_combobox",
                        config.keyboard, "default_key_action")
        self.bind_combobox_id("key_synth_combobox",
                        config.keyboard, "key_synth")

        def get_sticky_key_behavior(config_object, key):
            behaviors = getattr(config_object, key)
            return behaviors.get("all", "")
        def set_sticky_key_behavior(config_object, key, value):
            behaviors = getattr(config_object, key).copy()
            behaviors["all"] = value
            setattr(config_object, key, behaviors)
        self.bind_combobox_id("sticky_key_behavior_combobox",
                        config.keyboard, "sticky_key_behavior",
                        get_sticky_key_behavior, set_sticky_key_behavior)
        self.bind_spin("sticky_key_release_delay_spinbutton",
                            config.keyboard, "sticky_key_release_delay")
        self.bind_combobox_id("touch_input_combobox",
                        config.keyboard, "touch_input")
        self.bind_combobox_id("input_event_source_combobox",
                        config.keyboard, "input_event_source")

        # word suggestions
        self._page_word_suggestions = PageWordSuggestions(builder)

        # window, docking
        self.docking_enabled_toggle = \
                             builder.get_object("docking_enabled_toggle")
        self.docking_box = builder.get_object("docking_box")

        def on_docking_enabled_config_set(config_object, key, value):
            setattr(config_object, key, value)
            self.update_window_widgets()
        self.bind_check("docking_enabled_toggle",
                        config.window, "docking_enabled",
                        config_set_callback = on_docking_enabled_config_set)
        self.bind_button("docking_settings_button",
                         lambda widget: DockingDialog().run(self.window))

        self.update_window_widgets()

        # layout view
        self.layout_view = builder.get_object("layout_view")
        self.user_layout_root = config.get_user_layout_dir()
        config.layout_notify_add(lambda x: self.update_layout_view_selection())
        self.update_layout_view()
        self.update_layout_widgets()

        # theme view
        self.theme_view = builder.get_object("theme_view")
        self.theme_view.append_column(Gtk.TreeViewColumn(None,
                                                         Gtk.CellRendererText(),
                                                         markup=0))
        self.delete_theme_button = builder.get_object("delete_theme_button")
        self.delete_theme_button
        self.customize_theme_button = \
                                   builder.get_object("customize_theme_button")

        self.update_themeList()
        config.theme_notify_add(self.on_theme_changed)

        self.system_theme_tracking_enabled_toggle = \
                    builder.get_object("system_theme_tracking_enabled_toggle")
        self.system_theme_tracking_enabled_toggle.set_active( \
                                        config.system_theme_tracking_enabled)
        config.system_theme_tracking_enabled_notify_add( \
                                        self.on_system_theme_tracking_changed)

        # Snippets
        self.snippet_view = SnippetView()
        builder.get_object("snippet_scrolled_window").add(self.snippet_view)

        # Universal Access
        scanner_enabled = builder.get_object("scanner_enabled")
        scanner_enabled.set_active(config.scanner.enabled)
        config.scanner.enabled_notify_add(scanner_enabled.set_active)

        self.hide_click_type_window_toggle = \
                builder.get_object("hide_click_type_window_toggle")
        self.hide_click_type_window_toggle.set_active( \
                      config.universal_access.hide_click_type_window)
        config.universal_access.hide_click_type_window_notify_add( \
                      self.hide_click_type_window_toggle.set_active)

        self.enable_click_type_window_on_exit_toggle = \
                builder.get_object("enable_click_type_window_on_exit_toggle")
        self.enable_click_type_window_on_exit_toggle.set_active( \
                      config.universal_access.enable_click_type_window_on_exit)
        config.universal_access.enable_click_type_window_on_exit_notify_add( \
                      self.enable_click_type_window_on_exit_toggle.set_active)

        self.num_resize_handles_combobox = \
                         builder.get_object("num_resize_handles_combobox")
        self.update_num_resize_handles_combobox()
        config.resize_handles_notify_add( \
                            lambda x: self.select_num_resize_handles())

        if config.mousetweaks:
            self.bind_spin("hover_click_delay_spinbutton",
                            config.mousetweaks, "dwell_time")
            self.bind_spin("hover_click_motion_threshold_spinbutton",
                            config.mousetweaks, "dwell_threshold")

        # select last active page
        page = config.current_settings_page
        self.settings_notebook = builder.get_object("settings_notebook")
        self.settings_notebook.set_current_page(page)

        self.pages_view = builder.get_object("pages_view")
        sel = self.pages_view.get_selection()
        if sel:
            sel.select_path(Gtk.TreePath(page))

        self.window.show_all()

        # disable hover click controls if mousetweaks isn't installed
        frame = builder.get_object("hover_click_frame")
        frame.set_sensitive(bool(config.mousetweaks))

        self.window.set_keep_above(not mainwin)

        self.window.connect("destroy", Gtk.main_quit)
        builder.connect_signals(self)

        _logger.info("Entering mainloop of Onboard-settings")
        Gtk.main()

    def on_pages_view_cursor_changed(self, widget):
        sel = widget.get_selection()
        if sel:
            paths = sel.get_selected_rows()[1]
            if paths:
                page_num = paths[0].get_indices()[0]
                config.current_settings_page = page_num
                self.settings_notebook.set_current_page(page_num)

    def on_settings_notebook_switch_page(self, widget, gpage, page_num):
        config.current_settings_page = page_num

    def on_snippet_add_button_clicked(self, event):
        _logger.info("Snippet add button clicked")
        self.snippet_view.append("","")

    def on_snippet_remove_button_clicked(self, event):
        _logger.info("Snippet remove button clicked")
        self.snippet_view.remove_selected()

    def on_auto_show_toggled(self, widget):
        active = widget.get_active()
        if active and \
           not config.check_gnome_accessibility(self.window):
            active = False
        config.auto_show.enabled = active
        self.update_window_widgets()

    def on_status_icon_toggled(self,widget):
        config.show_status_icon = widget.get_active()
        self.update_window_widgets()

    def on_start_minimized_toggled(self,widget):
        config.start_minimized = widget.get_active()

    def on_icon_palette_toggled(self, widget):
        if not config.is_icon_palette_last_unhide_option():
            config.icp.in_use = widget.get_active()
        self.update_window_widgets()

    def on_modeless_gksu_toggled(self, widget):
        config.modeless_gksu = widget.get_active()

    def on_xembed_onboard_toggled(self, widget):
        config.enable_gss_embedding(widget.get_active())

    def on_show_tooltips_toggled(self, widget):
        config.show_tooltips = widget.get_active()

    def on_window_decoration_toggled(self, widget):
        if not config.is_force_to_top():
            config.window.window_decoration = widget.get_active()
        self.update_window_widgets()

    def on_window_state_sticky_toggled(self, widget):
        if not config.is_force_to_top():
            config.window.window_state_sticky = widget.get_active()

    def on_force_to_top_toggled(self, widget):
        if not config.is_docking_enabled():
            config.window.force_to_top = widget.get_active()
        self.update_window_widgets()

    def on_keep_aspect_ratio_toggled(self,widget):
        config.window.keep_aspect_ratio = widget.get_active()

    def update_window_widgets(self):
        force_to_top =  config.is_force_to_top()

        self.icon_palette_toggle.set_sensitive( \
                             not config.is_icon_palette_last_unhide_option())
        active = config.is_icon_palette_in_use()
        if self.icon_palette_toggle.get_active() != active:
            self.icon_palette_toggle.set_active(active)

        self.window_decoration_toggle.set_sensitive(not force_to_top)
        active = config.has_window_decoration()
        if self.window_decoration_toggle.get_active() != active:
            self.window_decoration_toggle.set_active(active)

        self.window_state_sticky_toggle.set_sensitive( not force_to_top)
        active = config.get_sticky_state()
        if self.window_state_sticky_toggle.get_active() != active:
            self.window_state_sticky_toggle.set_active(active)

        self.force_to_top_toggle.set_sensitive(not config.is_docking_enabled())
        active = force_to_top
        if self.force_to_top_toggle.get_active() != active:
            self.force_to_top_toggle.set_active(active)

        self.background_transparency_spinbutton.set_sensitive( \
                                        not config.has_window_decoration())
        self.start_minimized_toggle.set_sensitive(\
                                        not config.auto_show.enabled)

        self.auto_show_toggle.set_active(config.auto_show.enabled)

        self.inactivity_frame.set_sensitive(not config.scanner.enabled)
        active = config.is_inactive_transparency_enabled()
        if self.enable_inactive_transparency_toggle.get_active() != active:
            self.enable_inactive_transparency_toggle.set_active(active)

    def update_all_widgets(self):
        pass

    def on_transparent_background_toggled(self, widget):
        config.window.transparent_background = widget.get_active()
        self.update_window_widgets()

    def on_transparency_changed(self, widget):
        config.window.transparency = widget.get_value()

    def on_background_transparency_spinbutton_changed(self, widget):
        config.window.background_transparency = widget.get_value()

    def on_enable_inactive_transparency_toggled(self, widget):
        if not config.scanner.enabled:
            config.window.enable_inactive_transparency = widget.get_active()

    def on_inactive_transparency_changed(self, widget):
        config.window.inactive_transparency = widget.get_value()

    def on_inactive_transparency_delay_changed(self, widget):
        config.window.inactive_transparency_delay = widget.get_value()

    def on_layout_new_button_clicked(self, widget):
        name = self.get_selected_layout_value(self.LAYOUT_COL_NAME)
        filename = self.get_selected_layout_filename()
        if filename:
            new_layout_name = show_ask_string_dialog(
                _format("Copy layout '{}' to this new name:", name), self.window)
            if new_layout_name:
                new_filename = \
                    os.path.join(self.user_layout_root, new_layout_name) + \
                    config.LAYOUT_FILE_EXTENSION
                LayoutLoaderSVG.copy_layout(filename, new_filename)
                self.update_layout_view()
                self.open_user_layout_dir()

    def on_layout_remove_button_clicked(self, event):
        name = self.get_selected_layout_value(self.LAYOUT_COL_NAME)
        filename = self.get_selected_layout_filename()
        if filename:
            question = _format("Delete layout '{}'?", name)
            if show_confirmation_dialog(question, self.window):
                LayoutLoaderSVG.remove_layout(filename)

                config.layout_filename = self.layout_view_model[0][1] \
                                        if len(self.layout_view_model) else ""
                self.update_layout_view()

    def open_user_layout_dir(self):
        if os.path.exists('/usr/bin/nautilus'):
            os.system(("nautilus --no-desktop %s" %self.user_layout_root))
        elif os.path.exists('/usr/bin/thunar'):
            os.system(("thunar %s" %self.user_layout_root))
        else:
            _logger.warning(_("No file manager to open layout folder"))

    def on_layout_folder_button_clicked(self, widget):
        self.open_user_layout_dir()

    def update_layout_widgets(self):
        filename = self.get_selected_layout_filename()
        self.wid("layout_new_button").set_sensitive(not filename is None)
        self.wid("layout_remove_button").set_sensitive(not filename is None and \
                                         os.access(filename, os.W_OK))
        has_about_info = bool( \
            self.get_selected_layout_value(self.LAYOUT_COL_HAS_ABOUT_INFO))
        self.wid("layout_about_button").set_sensitive(has_about_info)

    def on_scanner_enabled_toggled(self, widget):
        config.scanner.enabled = widget.get_active()
        self.update_window_widgets()

    def on_scanner_settings_clicked(self, widget):
        ScannerDialog().run(self.window)

    def on_hide_click_type_window_toggled(self, widget):
        config.universal_access.hide_click_type_window = widget.get_active()

    def on_enable_click_type_window_on_exit_toggle(self, widget):
        config.universal_access.enable_click_type_window_on_exit = widget.get_active()

    def on_hover_click_settings_clicked(self, widget):
        filename = "gnome-control-center"
        try:
            Popen([filename, "universal-access"])
        except OSError as e:
            _logger.warning(_format("System settings not found ({}): {}",
                                    filename, unicode_str(e)))

    def update_num_resize_handles_combobox(self):
        self.num_resize_handles_list = Gtk.ListStore(str, int)
        self.num_resize_handles_combobox.set_model(self.num_resize_handles_list)
        cell = Gtk.CellRendererText()
        self.num_resize_handles_combobox.clear()
        self.num_resize_handles_combobox.pack_start(cell, True)
        self.num_resize_handles_combobox.add_attribute(cell, 'markup', 0)

        self.num_resize_handles_choices = [
                           # Frame resize handles: None
                           [_("None"), NumResizeHandles.NONE],
                           # Frame resize handles: Corners only
                           [_("Corners only"), NumResizeHandles.SOME],
                           # Frame resize handles: All
                           [_("All corners and edges"),  NumResizeHandles.ALL]
                           ]

        for name, id in self.num_resize_handles_choices:
            it = self.num_resize_handles_list.append((name, id))

        self.select_num_resize_handles()

    def select_num_resize_handles(self):
        num = config.get_num_resize_handles()
        for row in self.num_resize_handles_list:
            if row[1] == num:
                it = row.model.get_iter(row.path)
                self.num_resize_handles_combobox.set_active_iter(it)
                break

    def on_num_resize_handles_combobox_changed(self, widget):
        value = self.num_resize_handles_list.get_value( \
                        self.num_resize_handles_combobox.get_active_iter(),1)
        config.set_num_resize_handles(value)

    def on_close_button_clicked(self, widget):
        self.window.destroy()
        Gtk.main_quit()

    def update_layout_view(self):
        model = self.layout_view.get_model()
        self.layout_view_model = model
        model.clear()

        sort_order = ["Small", "Compact", "Full Keyboard", "Phone", "Grid"]
        layout_infos = self._read_layouts(
            os.path.join(config.install_dir, "layouts"), sort_order)

        system = [li for li in layout_infos
                    if li.layout_section == "system"]
        contributed = [li for li in layout_infos
                    if li.layout_section == "contributions"]

        user = self._read_layouts(self.user_layout_root)

        self._add_layout_section(model, system, _("Core layouts"))
        self._add_layout_section(model, contributed, _("Contributions"))
        self._add_layout_section(model, user, _("User layouts"))

        self.layout_view.expand_all()
        self.update_layout_view_selection()

    def update_layout_view_selection(self):
        self.select_tree_view_row(self.layout_view, self.LAYOUT_COL_FILENAME,
                                  config.layout_filename)

    def _add_layout_section(self, model, lis, section_name):
        if lis:
            parent_iter = model.append(None)
            model.set(parent_iter,
                    self.LAYOUT_COL_NAME, "<b>{}</b>".format(section_name))
            for li in lis:
                child_iter = model.append(parent_iter)
                model.set(child_iter,
                        self.LAYOUT_COL_NAME, li.id_string,
                        self.LAYOUT_COL_SUMMARY, li.summary,
                        self.LAYOUT_COL_FILENAME, li.filename,
                        self.LAYOUT_COL_HAS_ABOUT_INFO, li.has_about_info,
                        self.LAYOUT_COL_IS_ROW_SENSITIVE, bool(li.filename))

    def on_layout_about_button_clicked(self, event = None):
        fn = self.get_selected_layout_filename()
        li = self._read_layout(fn)
        if li is None:
            return

        markup = "<big>{}</big>\n".format(li.id)
        body = li.description or li.summary
        if body:
            markup += "\n{}\n".format(body)
        if li.author:
            markup += ("\n" + _("Author: {}") + "\n").format(li.author)
        markup += "\n <tt>{}</tt>\n".format(li.filename)

        dialog = Gtk.MessageDialog(title=_("About Layout"),
                                   message_type=Gtk.MessageType.QUESTION,
                                   buttons=Gtk.ButtonsType.OK)
        dialog.set_markup(markup)
        dialog.set_transient_for(self.window)
        dialog.run()
        dialog.destroy()

    def _read_layouts(self, path,  sort_order=()):
        filenames = self._find_layouts(path)

        layout_infos = []
        for filename in filenames:
            li = self._read_layout(filename, sort_order)
            if li:
                layout_infos.append(li)

        return sorted(layout_infos, key=lambda x: x.sort_key)

    def _read_layout(self, filename, sort_order=()):
        li = None

        if filename and os.path.exists(filename):
            file_object = open_utf8(filename)
            try:
                dom_node = minidom.parse(file_object).documentElement

                class LayoutInfo: pass
                li = LayoutInfo()
                id = dom_node.attributes["id"].value
                sort_priority = sort_order.index(id) \
                                if id in sort_order else 1000
                li.id = id
                li.filename = filename
                li.layout_section = self._get_dom_string(dom_node, "section")
                li.summary = _(self._get_dom_string(dom_node, "summary"))
                li.description = \
                    _(self._get_dom_string(dom_node, "description"))
                li.author = self._get_dom_string(dom_node, "author")
                li.sort_key = (li.layout_section.lower(), sort_priority, id.lower())
                li.has_about_info = True
                li.id_string = id

            except ExpatError as ex:
                _logger.error("XML in %s %s" % (filename, unicode_str(ex)))
                li = None
            except KeyError as ex:
                _logger.error("key %s required in %s" % (unicode_str(ex), filename))
                li = None

            file_object.close()

        return li

    @staticmethod
    def _get_dom_string(dom_node, attribute, default = ""):
        if dom_node.hasAttribute(attribute):
            return dom_node.attributes[attribute].value
        return default

    def _find_layouts(self, path):
        layouts = []
        try:
            files = os.listdir(path)
        except OSError:
            files = []
        for filename in files:
            if filename.endswith(".sok") or \
               filename.endswith(config.LAYOUT_FILE_EXTENSION):
                layouts.append(os.path.join(path, filename))
        return layouts

    def on_layout_view_select_cursor_row(self, treeview, *args):
        print(args)
        return False

    def on_layout_view_row_activated(self, treeview, path, view_column):
        #self.on_layout_about_button_clicked() # too annoying
        pass

    def on_layout_view_cursor_changed(self, widget):
        filename = self.get_selected_layout_filename()
        if filename:
            config.layout_filename = filename
        self.update_layout_widgets()

    def get_selected_layout_filename(self):
        sel = self.layout_view.get_selection()
        if sel:
            it = sel.get_selected()[1]
            if it:
                return self.layout_view_model.get_value(it,
                                                    self.LAYOUT_COL_FILENAME)
        return None

    def get_selected_layout_value(self, col_index):
        sel = self.layout_view.get_selection()
        if sel:
            it = sel.get_selected()[1]
            if it:
                return self.layout_view_model.get_value(it, col_index)
        return None

    def on_new_theme_button_clicked(self, widget):
        while True:
            new_name = show_ask_string_dialog(
                _("Enter a name for the new theme:"), self.window)
            if not new_name:
                return

            new_filename = Theme.build_user_filename(new_name)
            if not os.path.exists(new_filename):
                break

            question = _format("This theme file already exists.\n'{filename}'"
                               "\n\nOverwrite it?",
                               filename=new_filename)
            if show_confirmation_dialog(question, self.window):
                break

        theme = self.get_selected_theme()
        if not theme:
            theme = Theme()
        theme.save_as(new_name, new_name)
        config.theme_filename = theme.filename
        self.update_themeList()

    def on_delete_theme_button_clicked(self, widget):
        theme = self.get_selected_theme()
        if theme and not theme.is_system:
            if self.get_hidden_theme(theme):
                question = _("Reset selected theme to Onboard defaults?")
            else:
                question = _("Delete selected theme?")
            reply = show_confirmation_dialog(question, self.window)
            if reply == True:
                # be sure the file hasn't been deleted from outside already
                if os.path.exists(theme.filename):
                    os.remove(theme.filename)

                # Is there a system theme behind the deleted one?
                hidden_theme = self.get_hidden_theme(theme)
                if hidden_theme:
                    config.theme_filename = hidden_theme.filename

                else: # row will disappear
                    # find a neighboring theme to select after deletion
                    near_theme = self.find_neighbor_theme(theme)
                    config.theme_filename = near_theme.filename \
                                            if near_theme else ""

                self.update_themeList()

                # notify gsettings clients
                theme = self.get_selected_theme()
                if theme:
                    theme.apply()

    def find_neighbor_theme(self, theme):
        themes = self.get_sorted_themes()
        for i, tpl in enumerate(themes):
            if theme.basename == tpl[0].basename:
                if i < len(themes)-1:
                    return themes[i+1][0]
                else:
                    return themes[i-1][0]
        return None

    def on_system_theme_tracking_enabled_toggled(self, widget):
        config.system_theme_tracking_enabled = widget.get_active()

    def on_customize_theme_button_clicked(self, widget):
        self.customize_theme()

    def on_theme_view_row_activated(self, treeview, path, view_column):
        self.customize_theme()

    def on_theme_view_cursor_changed(self, widget):
        theme = self.get_selected_theme()
        if theme:
            theme.apply()
            config.theme_filename = theme.filename
        self.update_theme_buttons()

    def get_sorted_themes(self):
        #return sorted(self.themes.values(), key=lambda x: x[0].name)
        is_system = [x for x in list(self.themes.values()) if x[0].is_system or x[1]]
        user = [x for x in list(self.themes.values()) if not (x[0].is_system or x[1])]
        return sorted(is_system, key=lambda x: x[0].name.lower()) + \
               sorted(user, key=lambda x: x[0].name.lower())

    def find_theme_index(self, theme):
        themes = self.get_sorted_themes()
        for i,tpl in enumerate(themes):
            if theme.basename == tpl[0].basename:
                return i
        return -1

    def customize_theme(self):
        theme = self.get_selected_theme()
        if theme:
            system_theme = self.themes[theme.basename][1]

            dialog = ThemeDialog(self, theme)
            modified_theme = dialog.run()

            if modified_theme == system_theme:
                # same as the system theme, so delete the user theme
                _logger.info("Deleting theme '%s'" % theme.filename)
                if os.path.exists(theme.filename):
                    os.remove(theme.filename)

            elif not modified_theme == theme:
                # save as user theme
                modified_theme.save_as(theme.basename, theme.name)
                config.theme_filename = modified_theme.filename
                _logger.info("Saved theme '%s'" % theme.filename)

        self.update_themeList()

    def on_system_theme_tracking_changed(self, x):
        self.system_theme_tracking_enabled_toggle.set_active( \
                                        config.system_theme_tracking_enabled)
        config.load_theme()
        self.on_theme_changed()

    def on_theme_changed(self, theme_filename = None):
        selected = self.get_selected_theme_filename()
        if selected != config.theme_filename:
            self.update_themeList()

    def update_themeList(self):
        self.themeList = Gtk.ListStore(str, str)
        self.theme_view.set_model(self.themeList)

        self.themes = Theme.load_merged_themes()

        theme_basename = \
               os.path.splitext(os.path.basename(config.theme_filename))[0]
        it_selection = None
        for theme,hidden_theme in self.get_sorted_themes():
            it = self.themeList.append((
                         format_list_item(theme.name, theme.is_system),
                         theme.filename))
            if theme.basename == theme_basename:
                sel = self.theme_view.get_selection()
                if sel:
                    sel.select_iter(it)
                it_selection = it

        # scroll to selection
        if it_selection:
            path = self.themeList.get_path(it_selection)
            self.theme_view.scroll_to_cell(path)

        self.update_theme_buttons()

    def update_theme_buttons(self):
        theme = self.get_selected_theme()

        if theme and (self.get_hidden_theme(theme) or theme.is_system):
            self.delete_theme_button.set_label(_("Reset"))
        else:
            self.delete_theme_button.set_label(Gtk.STOCK_DELETE)

        self.delete_theme_button.set_sensitive(bool(theme) and not theme.is_system)
        self.customize_theme_button.set_sensitive(bool(theme))

    def get_hidden_theme(self, theme):
        if theme:
            return self.themes[theme.basename][1]
        return None

    def get_selected_theme(self):
        filename = self.get_selected_theme_filename()
        if filename:
            basename = os.path.splitext(os.path.basename(filename))[0]
            if basename in self.themes:
                return self.themes[basename][0]
        return None

    def get_selected_theme_filename(self):
        sel = self.theme_view.get_selection()
        if sel:
            it = sel.get_selected()[1]
            if it:
                return self.themeList.get_value(it, 1)
        return None


class PageWordSuggestions(DialogBuilder):
    """ Word Suggestions """

    def __init__(self, builder):
        DialogBuilder.__init__(self, builder)

        self.wid("enable_word_suggestions_toggle") \
                .connect_after("toggled", lambda x: self._update_ui())
        self.bind_check("enable_word_suggestions_toggle",
                        config.word_suggestions, "enabled")

        self.wid("auto_learn_toggle") \
                .connect_after("toggled", lambda x: self._update_ui())
        self.bind_check("auto_learn_toggle",
                            config.wp, "auto_learn")

        self.bind_check("punctuation_assistence_toggle",
                            config.wp, "punctuation_assistance")
        self.bind_check("auto_capitalization_toggle",
                            config.typing_assistance, "auto_capitalization")
        self.bind_check("auto_correction_toggle",
                            config.typing_assistance, "auto_correction")
        self.bind_check("enable_spell_check_toggle",
                            config.word_suggestions, "spelling_suggestions_enabled")

        self.bind_check("language_button_toggle",
            config.word_suggestions, "wordlist_buttons",
            config_get_callback = lambda co, key: \
                    config.word_suggestions.can_show_language_button(),
            config_set_callback = lambda co, key, value: \
                    config.word_suggestions.show_language_button(value))

        self.bind_check("pause_learning_button_toggle",
            config.word_suggestions, "wordlist_buttons",
            config_get_callback = lambda co, key: \
                    config.word_suggestions.can_show_pause_learning_button(),
            config_set_callback = lambda co, key, value: \
                    config.word_suggestions.show_pause_learning_button(value))

        #self.bind_check("show_context_line_toggle",
        #                config.word_suggestions, "show_context_line")
        self._init_spell_checker_backend_combo()

        self._update_ui()

    def _init_spell_checker_backend_combo(self):
        combo = self.wid("spell_check_backend_combobox")
        combo.set_active(config.typing_assistance.spell_check_backend)
        combo.connect("changed", self.on_spell_check_backend_changed)
        config.typing_assistance.spell_check_backend_notify_add(self._backend_notify)

    def on_spell_check_backend_changed(self, widget):
        config.typing_assistance.spell_check_backend = widget.get_active()

    def _backend_notify(self, mode):
        self.wid("spell_check_backend_combobox").set_active(mode)

    def _update_ui(self):
        self.wid("word_suggestions_general_box1") \
                .set_sensitive(config.are_word_suggestions_enabled())
        self.wid("pause_learning_button_toggle") \
                .set_sensitive(config.word_suggestions.auto_learn)


class DockingDialog(DialogBuilder):
    """ Dialog "Docking Settings" """

    def __init__(self):

        builder = LoadUI("settings_docking_dialog")

        DialogBuilder.__init__(self, builder)

        self.bind_check("docking_shrink_workarea_toggle",
                        config.window, "docking_shrink_workarea")
        self.bind_check("landscape_dock_expand_toggle",
                        config.window.landscape, "dock_expand")
        self.bind_check("portrait_dock_expand_toggle",
                        config.window.portrait, "dock_expand")
        self.bind_combobox_id("docking_edge_combobox",
                        config.window, "docking_edge")

        self.update_ui()

    def run(self, parent):
        dialog = self.wid("dialog")
        dialog.set_transient_for(parent)
        dialog.run()
        dialog.destroy()

    def update_ui(self):
        pass


class ThemeDialog(DialogBuilder):
    """ Customize theme dialog """

    current_page = 0

    def __init__(self, settings, theme):

        self.original_theme = theme
        self.theme = copy.deepcopy(theme)

        builder = LoadUI("settings_theme_dialog")
        DialogBuilder.__init__(self, builder)

        self.dialog = builder.get_object("customize_theme_dialog")

        self.theme_notebook = builder.get_object("theme_notebook")

        self.key_style_combobox = builder.get_object("key_style_combobox")
        self.color_scheme_combobox = builder.get_object("color_scheme_combobox")
        self.font_combobox = builder.get_object("font_combobox")
        self.font_attributes_view = builder.get_object("font_attributes_view")
        self.background_gradient_scale = builder.get_object(
                                               "background_gradient_scale")
        self.key_roundness_scale = builder.get_object(
                                               "key_roundness_scale")
        self.key_size_scale = builder.get_object(
                                               "key_size_scale")
        self.gradients_box = builder.get_object("gradients_box")
        self.key_fill_gradient_scale = builder.get_object(
                                               "key_fill_gradient_scale")
        self.key_stroke_gradient_scale = builder.get_object(
                                               "key_stroke_gradient_scale")
        self.key_gradient_direction_scale = builder.get_object(
                                               "key_gradient_direction_scale")
        self.key_shadow_strength_scale = builder.get_object(
                                               "key_shadow_strength_scale")
        self.key_shadow_size_scale = builder.get_object(
                                               "key_shadow_size_scale")
        self.revert_button = builder.get_object("revert_button")
        self.superkey_label_combobox = builder.get_object(
                                               "superkey_label_combobox")
        self.superkey_label_size_checkbutton = builder.get_object(
                                            "superkey_label_size_checkbutton")
        self.superkey_label_model = builder.get_object("superkey_label_model")

        def on_key_stroke_width_value_changed(value):
            self.theme.key_stroke_width = value
            self.update_sensivity()
        self.bind_scale("key_stroke_width_scale",
                        config.theme_settings, "key_stroke_width",
                        widget_callback = on_key_stroke_width_value_changed)

        self.update_ui()

        self.dialog.set_transient_for(settings.window)
        self.theme_notebook.set_current_page(ThemeDialog.current_page)

        builder.connect_signals(self)

    def run(self):
        # do response processing ourselves to stop the
        # revert button from closing the dialog
        self.dialog.set_modal(True)
        self.dialog.show()
        Gtk.main()
        self.dialog.destroy()
        return self.theme

    def on_response(self, dialog, response_id):
        if response_id == Gtk.ResponseType.DELETE_EVENT:
            pass
        if response_id == \
            self.dialog.get_response_for_widget(self.revert_button):

            # revert changes and keep the dialog open
            self.theme = copy.deepcopy(self.original_theme)

            self.update_ui()
            self.theme.apply()
            return

        Gtk.main_quit()

    def update_ui(self):
        self.in_update = True

        self.update_key_styleList()
        self.update_color_schemeList()
        self.update_fontList()
        self.update_font_attributesList()
        self.background_gradient_scale.set_value(self.theme.background_gradient)
        self.key_roundness_scale.set_value(self.theme.roundrect_radius)
        self.key_size_scale.set_value(self.theme.key_size)
        self.key_fill_gradient_scale.set_value(self.theme.key_fill_gradient)
        self.key_stroke_gradient_scale. \
                set_value(self.theme.key_stroke_gradient)
        self.key_gradient_direction_scale. \
                set_value(self.theme.key_gradient_direction)
        self.key_shadow_strength_scale. \
                set_value(self.theme.key_shadow_strength)
        self.key_shadow_size_scale. \
                set_value(self.theme.key_shadow_size)
        self.update_superkey_labelList()
        self.superkey_label_size_checkbutton. \
                set_active(bool(self.theme.get_superkey_size_group()))

        self.update_sensivity()

        self.in_update = False

    def update_sensivity(self):
        self.revert_button.set_sensitive(not self.theme == self.original_theme)

        has_gradient = self.theme.key_style != "flat"
        self.gradients_box.set_sensitive(has_gradient)
        self.superkey_label_size_checkbutton.\
                      set_sensitive(bool(self.theme.get_superkey_label()))

    def update_key_styleList(self):
        self.key_style_list = Gtk.ListStore(str,str)
        self.key_style_combobox.set_model(self.key_style_list)
        cell = Gtk.CellRendererText()
        self.key_style_combobox.clear()
        self.key_style_combobox.pack_start(cell, True)
        self.key_style_combobox.add_attribute(cell, 'markup', 0)

        self.key_styles = [
                           # Key style with flat fill- and border colors
                           [_("Flat"), "flat"],
                           # Key style with simple gradients
                           [_("Gradient"), "gradient"],
                           # Key style for dish-like key caps
                           [_("Dish"), "dish"]
                           ]
        for name, id in self.key_styles:
            it = self.key_style_list.append((name, id))
            if id == self.theme.key_style:
                self.key_style_combobox.set_active_iter(it)

    def update_color_schemeList(self):
        self.color_scheme_list = Gtk.ListStore(str,str)
        self.color_scheme_combobox.set_model(self.color_scheme_list)
        cell = Gtk.CellRendererText()
        self.color_scheme_combobox.clear()
        self.color_scheme_combobox.pack_start(cell, True)
        self.color_scheme_combobox.add_attribute(cell, 'markup', 0)

        self.color_schemes = ColorScheme.get_merged_color_schemes()
        color_scheme_filename = self.theme.get_color_scheme_filename()
        for color_scheme in sorted(list(self.color_schemes.values()),
                                   key=lambda x: x.name):
            it = self.color_scheme_list.append((
                      format_list_item(color_scheme.name, color_scheme.is_system),
                      color_scheme.filename))
            if color_scheme.filename == color_scheme_filename:
                self.color_scheme_combobox.set_active_iter(it)

    def update_fontList(self):
        self.font_list = Gtk.ListStore(str,str)
        self.font_combobox.set_model(self.font_list)
        cell = Gtk.CellRendererText()
        self.font_combobox.clear()
        self.font_combobox.pack_start(cell, True)
        self.font_combobox.add_attribute(cell, 'markup', 0)
        self.font_combobox.set_row_separator_func(
                                    self.font_combobox_row_separator_func,
                                    None)

        # work around https://bugzilla.gnome.org/show_bug.cgi?id=654957
        # "SIGSEGV when trying to call Pango.Context.list_families twice"
        global font_families
        if not "font_families" in globals():
            widget = Gtk.DrawingArea()
            context = widget.create_pango_context()
            font_families = context.list_families()
            widget.destroy()

        families = [(font.get_name(), font.get_name()) \
                    for font in font_families]

        families.sort(key=lambda x: x[0])
        families = [(_("Default"), "Normal"),
                    ("-", "-")] + families
        fd = Pango.FontDescription(self.theme.key_label_font)
        family = fd.get_family()
        for f in families:
            it = self.font_list.append(f)
            if  f[1] == family or \
               (f[1] == "Normal" and not family):
                self.font_combobox.set_active_iter(it)

    def font_combobox_row_separator_func(self, model, iter, data):
        return unicode_str(model.get_value(iter, 0)) == "-"

    def update_font_attributesList(self):
        treeview = self.font_attributes_view

        if not treeview.get_columns():
            liststore = Gtk.ListStore(bool, str, str)
            self.font_attributes_list = liststore
            treeview.set_model(liststore)

            column_toggle = Gtk.TreeViewColumn("Toggle")
            column_text = Gtk.TreeViewColumn("Text")
            treeview.append_column(column_toggle)
            treeview.append_column(column_text)

            cellrenderer_toggle = Gtk.CellRendererToggle()
            column_toggle.pack_start(cellrenderer_toggle, False)
            column_toggle.add_attribute(cellrenderer_toggle, "active", 0)

            cellrenderer_text = Gtk.CellRendererText()
            column_text.pack_start(cellrenderer_text, True)
            column_text.add_attribute(cellrenderer_text, "text", 1)
            cellrenderer_toggle.connect("toggled",
                             self.on_font_attributesList_toggle, liststore)

        liststore = treeview.get_model()
        liststore.clear()

        fd = Pango.FontDescription(self.theme.key_label_font)
        items = [[fd.get_weight() == Pango.Weight.BOLD,
                  _("Bold"), "bold"],
                 [fd.get_style() == Pango.Style.ITALIC,
                  _("Italic"), "italic"],
                 [fd.get_stretch() == Pango.Stretch.CONDENSED,
                  _("Condensed"), "condensed"],
                ]
        for checked, name, id in items:
            it = liststore.append((checked, name, id))
            if id == "":
                treeview.set_active_iter(it)

    def update_superkey_labelList(self):
        # block premature signals when calling model.clear()
        self.superkey_label_combobox.set_model(None)

        self.superkey_label_model.clear()
        self.superkey_labels = [["",      _("Default")],
                                [_(""), _("Ubuntu Logo")]
                               ]

        for label, descr in self.superkey_labels:
            self.superkey_label_model.append((label, descr))

        label = self.theme.get_superkey_label()
        self.superkey_label_combobox.get_child().set_text(label \
                                                          if label else "")

        self.superkey_label_combobox.set_model(self.superkey_label_model)

    def on_background_gradient_value_changed(self, widget):
        value = float(widget.get_value())
        config.theme_settings.background_gradient = value
        self.theme.background_gradient = value
        self.update_sensivity()

    def on_key_style_combobox_changed(self, widget):
        value = self.key_style_list.get_value( \
                            self.key_style_combobox.get_active_iter(),1)
        self.theme.key_style = value
        config.theme_settings.key_style = value
        self.update_sensivity()

    def on_key_roundness_value_changed(self, widget):
        radius = int(widget.get_value())
        config.theme_settings.roundrect_radius = radius
        self.theme.roundrect_radius = radius
        self.update_sensivity()

    def on_key_size_value_changed(self, widget):
        value = int(widget.get_value())
        config.theme_settings.key_size = value
        self.theme.key_size = value
        self.update_sensivity()

    def on_color_scheme_combobox_changed(self, widget):
        filename = self.color_scheme_list.get_value( \
                               self.color_scheme_combobox.get_active_iter(),1)
        self.theme.set_color_scheme_filename(filename)
        config.theme_settings.color_scheme_filename = filename
        self.update_sensivity()

    def on_key_fill_gradient_value_changed(self, widget):
        value = int(widget.get_value())
        config.theme_settings.key_fill_gradient = value
        self.theme.key_fill_gradient = value
        self.update_sensivity()

    def on_key_stroke_gradient_value_changed(self, widget):
        value = int(widget.get_value())
        config.theme_settings.key_stroke_gradient = value
        self.theme.key_stroke_gradient = value
        self.update_sensivity()

    def on_key_gradient_direction_value_changed(self, widget):
        value = int(widget.get_value())
        config.theme_settings.key_gradient_direction = value
        self.theme.key_gradient_direction = value
        self.update_sensivity()

    def on_key_shadow_strength_value_changed(self, widget):
        value = float(widget.get_value())
        config.theme_settings.key_shadow_strength = value
        self.theme.key_shadow_strength = value
        self.update_sensivity()

    def on_key_shadow_size_value_changed(self, widget):
        value = float(widget.get_value())
        config.theme_settings.key_shadow_size = value
        self.theme.key_shadow_size = value
        self.update_sensivity()

    def on_font_combobox_changed(self, widget):
        if not self.in_update:
            self.store_key_label_font()
            self.update_sensivity()

    def on_font_attributesList_toggle(self, widget, path, model):
        model[path][0] = not model[path][0]
        self.store_key_label_font()
        self.update_sensivity()

    def store_key_label_font(self):
        font = self.font_list.get_value(self.font_combobox.get_active_iter(),1)
        for row in self.font_attributes_list:
            if row[0]:
                font += " " + row[2]

        self.theme.key_label_font = font
        config.theme_settings.key_label_font = font

    def on_superkey_label_combobox_changed(self, widget):
        self.store_superkey_label_override()
        self.update_sensivity()

    def on_superkey_label_size_checkbutton_toggled(self, widget):
        self.store_superkey_label_override()
        self.update_sensivity()

    def store_superkey_label_override(self):
        label = self.superkey_label_combobox.get_child().get_text()
        if sys.version_info.major == 2:
            label = label.decode("utf8")
        if not label:
            label = None   # removes the override
        checked = self.superkey_label_size_checkbutton.get_active()
        size_group = config.SUPERKEY_SIZE_GROUP if checked else ""
        self.theme.set_superkey_label(label, size_group)
        config.theme_settings.key_label_overrides = \
                                          dict(self.theme.key_label_overrides)

    def on_theme_notebook_switch_page(self, widget, gpage, page_num):
        ThemeDialog.current_page = page_num


class ScannerDialog(DialogBuilder):
    """ Scanner settings dialog """

    """ Input device columns """
    COL_ICON_NAME   = 0
    COL_DEVICE_NAME = 1
    COL_DEVICE      = 2

    """ Device mapping columns """
    COL_NAME    = 0
    COL_ACTION  = 1
    COL_BUTTON  = 2
    COL_KEY     = 3
    COL_VISIBLE = 4
    COL_WEIGHT  = 5

    """ UI strings for scan actions """
    action_names = { ScanMode.ACTION_STEP     : _("Step"),
                     ScanMode.ACTION_LEFT     : _("Left"),
                     ScanMode.ACTION_RIGHT    : _("Right"),
                     ScanMode.ACTION_UP       : _("Up"),
                     ScanMode.ACTION_DOWN     : _("Down"),
                     ScanMode.ACTION_ACTIVATE : _("Activate") }

    """ List of actions a profile supports """
    supported_actions = [ [ScanMode.ACTION_STEP],
                          [ScanMode.ACTION_STEP],
                          [ScanMode.ACTION_STEP,
                           ScanMode.ACTION_ACTIVATE],
                          [ScanMode.ACTION_LEFT,
                           ScanMode.ACTION_RIGHT,
                           ScanMode.ACTION_UP,
                           ScanMode.ACTION_DOWN,
                           ScanMode.ACTION_ACTIVATE] ]

    def __init__(self):

        builder = LoadUI("settings_scanner_dialog")
        DialogBuilder.__init__(self, builder)

        self.device_manager = XIDeviceManager()
        self.device_manager.connect("device-event", self._on_device_event)
        self.pointer_selected = None
        self.mapping_renderer = None

        # order of execution is important
        self.init_input_devices()
        self.init_scan_modes()
        self.init_device_mapping()

        scanner = config.scanner
        self.bind_spin("cycles", scanner, "cycles")
        self.bind_spin("cycles_overscan", scanner, "cycles")
        self.bind_spin("cycles_stepscan", scanner, "cycles")
        self.bind_spin("step_interval", scanner, "interval")
        self.bind_spin("backtrack_interval", scanner, "interval")
        self.bind_spin("forward_interval", scanner, "interval_fast")
        self.bind_spin("backtrack_steps", scanner, "backtrack")
        self.bind_check("user_scan", scanner, "user_scan")
        self.bind_check("alternate", scanner, "alternate")
        self.bind_check("device_detach", scanner, "device_detach")

    def __del__(self):
        _logger.debug("ScannerDialog.__del__()")

    def run(self, parent):
        dialog = self.wid("dialog")
        dialog.set_transient_for(parent)
        dialog.run()
        dialog.destroy()

        config.scanner.disconnect_notifications()
        self.device_manager = None

    def init_scan_modes(self):
        combo = self.wid("scan_mode_combo")
        combo.set_active(config.scanner.mode)
        combo.connect("changed", self.on_scan_mode_changed)
        config.scanner.mode_notify_add(self._scan_mode_notify)
        self.wid("scan_mode_notebook").set_current_page(config.scanner.mode)

    def on_scan_mode_changed(self, widget):
        config.scanner.mode = widget.get_active()

    def _scan_mode_notify(self, mode):
        self.wid("scan_mode_combo").set_active(mode)
        self.wid("scan_mode_notebook").set_current_page(mode)
        self.update_device_mapping()

    def init_input_devices(self):
        combo = self.wid("input_device_combo")
        combo.set_model(Gtk.ListStore(str, str, GObject.TYPE_PYOBJECT))
        combo.add_attribute(self.wid("input_device_icon_renderer"),
                            "icon-name", self.COL_ICON_NAME)
        combo.add_attribute(self.wid("input_device_text_renderer"),
                            "text", self.COL_DEVICE_NAME)

        self.update_input_devices()

        combo.connect("changed", self.on_input_device_changed)
        config.scanner.device_name_notify_add(self._device_name_notify)

    def update_input_devices(self):
        devices = self.list_devices()
        model = self.wid("input_device_combo").get_model()
        model.clear()

        model.append(["input-mouse", ScanDevice.DEFAULT_NAME, None])

        for dev in devices:
            if dev.is_pointer():
                model.append(["input-mouse", dev.name, dev])

        for dev in devices:
            if not dev.is_pointer():
                model.append(["input-keyboard", dev.name, dev])

        self.select_current_device(config.scanner.device_name)

    def select_current_device(self, name):
        combo = self.wid("input_device_combo")
        model = combo.get_model()
        it = model.get_iter_first()
        if it is None:
            return

        if name == ScanDevice.DEFAULT_NAME:
            self.pointer_selected = True
            self.wid("device_detach").set_sensitive(False)
            combo.set_active_iter(it)
        else:
            while it:
                device = model.get_value(it, self.COL_DEVICE)
                if device and name == device.get_config_string():
                    self.pointer_selected = device.is_pointer()
                    self.wid("device_detach").set_sensitive(True)
                    combo.set_active_iter(it)
                    break
                it = model.iter_next(it)

        if self.mapping_renderer:
            self.mapping_renderer.set_property("pointer-mode",
                                               self.pointer_selected)

    def on_input_device_changed(self, combo):
        model = combo.get_model()
        it = combo.get_active_iter()
        if it is None:
            return

        config.scanner.device_detach = False
        device = model.get_value(it, self.COL_DEVICE)

        if device:
            config.scanner.device_name = device.get_config_string()
            self.wid("device_detach").set_sensitive(True)
            self.pointer_selected = device.is_pointer()
        else:
            config.scanner.device_name = ScanDevice.DEFAULT_NAME
            self.wid("device_detach").set_sensitive(False)
            self.pointer_selected = True

        if self.mapping_renderer:
            self.mapping_renderer.set_property("pointer-mode",
                                               self.pointer_selected)

    def _device_name_notify(self, name):
        self.select_current_device(name)
        self.update_device_mapping()

    def init_device_mapping(self):
        self.update_device_mapping()

        self.mapping_renderer = CellRendererMapping()
        self.mapping_renderer.set_property("pointer-mode", self.pointer_selected)
        self.mapping_renderer.connect("mapping-edited", self.on_mapping_edited)
        self.mapping_renderer.connect("mapping-cleared", self.on_mapping_cleared)

        column = self.wid("column_mapping")
        column.pack_start(self.mapping_renderer, False)
        column.add_attribute(self.mapping_renderer, "button", self.COL_BUTTON)
        column.add_attribute(self.mapping_renderer, "key", self.COL_KEY)
        column.add_attribute(self.mapping_renderer, "visible", self.COL_VISIBLE)

    def update_device_mapping(self):
        view = self.wid("device_mapping")
        model = view.get_model()
        model.clear()

        parent_iter = model.append(None)
        model.set(parent_iter,
                  self.COL_NAME, _("Action:"),
                  self.COL_WEIGHT, Pango.Weight.BOLD)

        for action in self.supported_actions[config.scanner.mode]:
            child_iter = model.append(parent_iter)
            model.set(child_iter,
                      self.COL_NAME, self.action_names[action],
                      self.COL_ACTION, action,
                      self.COL_VISIBLE, True,
                      self.COL_WEIGHT, Pango.Weight.NORMAL)

            if self.pointer_selected:
                button = self.get_value_for_action \
                    (action, config.scanner.device_button_map)
                if button:
                    model.set(child_iter, self.COL_BUTTON, button)
            else:
                key = self.get_value_for_action \
                    (action, config.scanner.device_key_map)
                if key:
                    model.set(child_iter, self.COL_KEY, key)

        view.expand_all()

    def on_mapping_edited(self, cell, path, value, pointer_mode):
        model = self.wid("device_mapping_model")
        it = model.get_iter_from_string(path)
        if it is None:
            return

        if pointer_mode:
            col = self.COL_BUTTON
            dev_map = config.scanner.device_button_map.copy()
        else:
            col = self.COL_KEY
            dev_map = config.scanner.device_key_map.copy()

        dup_it = model.get_iter_from_string("0:0")
        dup_val = None
        while dup_it:
            if value == model.get_value(dup_it, col):
                dup_val = model.get_value(dup_it, col)
                model.set(dup_it, col, 0)
                break
            dup_it = model.iter_next(dup_it)

        model.set(it, col, value)

        if dup_val in dev_map:
            del dev_map[dup_val]

        action = model.get_value(it, self.COL_ACTION)
        dev_map[value] = action

        for k, v in dev_map.items():
            if k != value and v == action:
                del dev_map[k]
                break

        if pointer_mode:
            config.scanner.device_button_map = dev_map
        else:
            config.scanner.device_key_map = dev_map

    def on_mapping_cleared(self, cell, path, pointer_mode):
        model = self.wid("device_mapping_model")
        it = model.get_iter_from_string(path)
        if it is None:
            return

        if pointer_mode:
            old_value = model.get_value(it, self.COL_BUTTON)
            model.set(it, self.COL_BUTTON, 0)
            if old_value in config.scanner.device_button_map:
                copy = config.scanner.device_button_map.copy()
                del copy[old_value]
                config.scanner.device_button_map = copy
        else:
            old_value = model.get_value(it, self.COL_KEY)
            model.set(it, self.COL_KEY, 0)
            if old_value in config.scanner.device_key_map:
                copy = config.scanner.device_key_map.copy()
                del copy[old_value]
                config.scanner.device_key_map = copy

    def list_devices(self):
        return [d for d in self.device_manager.get_devices() \
                if ScanDevice.is_useable(d) ]

    def _on_device_event(self, event):
        if event.xi_type in [XIEventType.DeviceAdded,
                             XIEventType.DeviceRemoved]:
            self.update_input_devices()

    def get_value_for_action(self, action, dev_map):
        for k, v in dev_map.items():
            if v == action:
                return k


MAX_GINT32 = (1 << 31) - 1

class CellRendererMapping(Gtk.CellRendererText):
    """
    Custom cell renderer that displays device buttons as labels.
    """

    __gproperties__ = { str('button')      : (GObject.TYPE_INT,
                                             '', '', 0, MAX_GINT32, 0,
                                             GObject.PARAM_READWRITE),
                        str('key')         : (GObject.TYPE_INT,
                                             '', '', 0, MAX_GINT32, 0,
                                             GObject.PARAM_READWRITE),
                        str('pointer-mode') : (bool, '', '', True,
                                             GObject.PARAM_READWRITE) }

    __gsignals__ = { str('mapping-edited') : (GObject.SIGNAL_RUN_LAST,
                                             None, (str, int, bool)),
                     str('mapping-cleared'): (GObject.SIGNAL_RUN_LAST,
                                             None, (str, bool)) }

    def __init__(self):
        super(CellRendererMapping, self).__init__(editable=True)

        self.key = 0
        self.button = 0
        self.pointer_mode = True

        self._edit_widget = None
        self._grab_widget = None
        self._grab_pointer = None
        self._grab_keyboard = None
        self._path = None
        self._bp_id = 0
        self._kp_id = 0
        self._se_id = 0
        self._sizing_label = None

        self._update_text_props()

    def do_get_property(self, prop):
        if prop.name == 'button':
            return self.button
        elif prop.name == 'key':
            return self.key
        elif prop.name == 'pointer-mode':
            return self.pointer_mode

    def do_set_property(self, prop, value):
        if prop.name == 'button':
            self.button = value
        elif prop.name == 'key':
            self.key = value
        elif prop.name == 'pointer-mode':
            self.pointer_mode = value

        self._update_text_props()

    def _update_text_props(self):

        if (self.pointer_mode and self.button == 0) or \
           (not self.pointer_mode and self.key == 0):
            self.set_property("style", Pango.Style.ITALIC)
            self.set_property("foreground-rgba", Gdk.RGBA(0.6, 0.6, 0.6, 1.0))
            text = _("Disabled")
        else:
            self.set_property("style", Pango.Style.NORMAL)
            self.set_property("foreground-set", False)

            if self.pointer_mode:
                text = "{} {!s}".format(_("Button"), self.button)
            else:
                text = Gdk.keyval_name(self.key)

        self.set_property("text", text)

    def _on_edit_widget_unrealize(self, widget):
        Gtk.device_grab_remove(self._grab_widget, self._grab_pointer)

        time = Gtk.get_current_event_time()
        self._grab_pointer.ungrab(time)
        self._grab_keyboard.ungrab(time)

    def _editing_done(self):
        self._grab_widget.handler_disconnect(self._bp_id)
        self._grab_widget.handler_disconnect(self._kp_id)
        self._grab_widget.handler_disconnect(self._se_id)
        self._edit_widget.editing_done()
        self._edit_widget.remove_widget()

    def _on_button_press(self, widget, event):
        self._editing_done()

        if self.pointer_mode:
            self.emit("mapping-edited",
                      self._path, event.button, self.pointer_mode)
        return True

    def _on_key_press(self, widget, event):
        self._editing_done()

        value = Gdk.keyval_to_lower(event.keyval)

        if value == Gdk.KEY_BackSpace:
            self.emit("mapping-cleared", self._path, self.pointer_mode)
        elif value == Gdk.KEY_Escape:
            pass
        else:
            if not self.pointer_mode:
                self.emit("mapping-edited",
                          self._path, value, self.pointer_mode)
        return True

    def _on_scroll_event(self, widget, event):
        self._editing_done()

        if self.pointer_mode:
            # mouse buttons 4 - 7 are delivered as scroll-events
            button = 4 + event.direction
            self.emit("mapping-edited",
                      self._path, button, self.pointer_mode)
        return True

    def do_get_preferred_width(self, widget):
        if self._sizing_label is None:
            self._sizing_label = Gtk.Label(label=_("Press a button..."))

        return self._sizing_label.get_preferred_width()

    def do_start_editing(self, event, widget, path, bg_area, cell_area, state):
        if not event: # else SEGFAULT when pressing a keyboard key twice
            return

        time = event.get_time()
        device = event.get_device()
        if device.get_source() == Gdk.InputSource.KEYBOARD:
            keyboard = device
            pointer = device.get_associated_device()
        else:
            pointer = device
            keyboard = device.get_associated_device()

        if keyboard.grab(widget.get_window(),
                         Gdk.GrabOwnership.WINDOW, False,
                         Gdk.EventMask.KEY_PRESS_MASK,
                         None, time) != Gdk.GrabStatus.SUCCESS:
            return

        if pointer.grab(widget.get_window(),
                        Gdk.GrabOwnership.WINDOW, False,
                        Gdk.EventMask.BUTTON_PRESS_MASK,
                        None, time) != Gdk.GrabStatus.SUCCESS:
            keyboard.ungrab(time)
            return

        Gtk.device_grab_add(widget, pointer, True)

        self._path = path
        self._grab_pointer = pointer
        self._grab_keyboard = keyboard
        self._grab_widget = widget
        self._bp_id = widget.connect("button-press-event", self._on_button_press)
        self._kp_id = widget.connect("key-press-event", self._on_key_press)
        self._se_id = widget.connect("scroll-event", self._on_scroll_event)

        style = widget.get_style_context()
        bg = style.get_background_color(Gtk.StateFlags.SELECTED)
        fg = style.get_color(Gtk.StateFlags.SELECTED)

        if self.pointer_mode:
            text = _("Press a button...")
        else:
            text = _("Press a key...")

        label = Gtk.Label(label=text,
                          halign=Gtk.Align.START,
                          valign=Gtk.Align.CENTER)
        label.override_color(Gtk.StateFlags.NORMAL, fg)

        self._edit_widget = EditableBox(label)
        self._edit_widget.override_background_color(Gtk.StateFlags.NORMAL, bg)
        self._edit_widget.connect("unrealize", self._on_edit_widget_unrealize)
        self._edit_widget.show_all()

        return self._edit_widget


class EditableBox(Gtk.EventBox, Gtk.CellEditable):
    """
    Container that implements the Gtk.CellEditable interface.
    """

    __gproperties__ = { str('editing-canceled'): (bool, '', '', False,
                                                  GObject.PARAM_READWRITE) }

    def __init__(self, child=None):
        super(EditableBox, self).__init__()

        self.editing_canceled = False

        if child:
            self.add(child)

    def do_get_property(self, prop):
        if prop.name == 'editing-canceled':
            return self.editing_canceled

    def do_set_property(self, prop, value):
        if prop.name == 'editing-canceled':
            self.editing_canceled = value

    def do_start_editing(self, event):
        pass


if __name__ == '__main__':
    s = Settings(True)

