# Copyright (C) 2007, Red Hat, Inc.
# Copyright (C) 2012, Daniel Francis
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.

"""
STABLE.
"""

import logging

from gi.repository import GObject
from gi.repository import Gtk

from sugar3.graphics.icon import Icon
from sugar3.graphics.palette import Palette, ToolInvoker


def _add_accelerator(tool_button):
    if not tool_button.props.accelerator or not tool_button.get_toplevel() or \
            not tool_button.get_child():
        return

    # TODO: should we remove the accelerator from the prev top level?
    if not hasattr(tool_button.get_toplevel(), 'sugar_accel_group'):
        logging.debug('No Gtk.AccelGroup in the top level window.')
        return

    accel_group = tool_button.get_toplevel().sugar_accel_group
    keyval, mask = Gtk.accelerator_parse(tool_button.props.accelerator)
    # the accelerator needs to be set at the child, so the Gtk.AccelLabel
    # in the palette can pick it up.
    accel_flags = Gtk.AccelFlags.LOCKED | Gtk.AccelFlags.VISIBLE
    tool_button.get_child().add_accelerator('clicked', accel_group,
                                            keyval, mask, accel_flags)


def _hierarchy_changed_cb(tool_button, previous_toplevel):
    _add_accelerator(tool_button)


def setup_accelerator(tool_button):
    _add_accelerator(tool_button)
    tool_button.connect('hierarchy-changed', _hierarchy_changed_cb)


class ToggleToolButton(Gtk.ToggleToolButton):
    '''
    UI for toggletoolbutton.
    A ToggleToolButton is a ToolItem that contains a toggle button,
    having an icon, a tooltip palette, and an accelerator.
    Use ToggleToolButton.new() to create a new ToggleToolButton.

    Args:
        accelerator (string): keyboard shortcut to be used to
        activate this button.
        Find about format here :
        https://developer.gnome.org/gtk3/stable/gtk3-Keyboard-Accelerators.html#gtk-accelerator-parse

        tooltip (string): tooltip to be displayed when user
        hovers over toggle button.

    Keyword Args:
        icon_name(string): name of themed icon which is to be used.
    '''

    __gtype_name__ = 'SugarToggleToolButton'

    def __init__(self, icon_name=None):
        GObject.GObject.__init__(self)

        self._palette_invoker = ToolInvoker(self)

        if icon_name:
            self.set_icon_name(icon_name)

        self.connect('destroy', self.__destroy_cb)

    def __destroy_cb(self, icon):
        if self._palette_invoker is not None:
            self._palette_invoker.detach()

    def set_icon_name(self, icon_name):
        '''
        Sets the icon for the tool button from a named themed icon.
        If it is none then no icon will be shown.

        Args:
            icon_name(string): The name for a themed icon.
            It can be set as 'None' too.

        Example:
            set_icon_name('view-radial')
        '''
        icon = Icon(icon_name=icon_name)
        self.set_icon_widget(icon)
        icon.show()

    def get_icon_name(self):
        '''
        The get_icon_name() method returns the value of the icon_name
        property that contains the name of a themed icon or None.
        '''
        if self.props.icon_widget is not None:
            return self.props.icon_widget.props.icon_name
        else:
            return None

    icon_name = GObject.property(type=str, setter=set_icon_name,
                                 getter=get_icon_name)

    def create_palette(self):
        return None

    def get_palette(self):
        return self._palette_invoker.palette

    def set_palette(self, palette):
        self._palette_invoker.palette = palette

    palette = GObject.property(
        type=object, setter=set_palette, getter=get_palette)

    def get_palette_invoker(self):
        return self._palette_invoker

    def set_palette_invoker(self, palette_invoker):
        self._palette_invoker.detach()
        self._palette_invoker = palette_invoker

    palette_invoker = GObject.property(
        type=object, setter=set_palette_invoker, getter=get_palette_invoker)

    def set_tooltip(self, text):
        '''
        Sets the tooltip of the toogle tool button. Displays when
        user hovers over the button with cursor.

        Args:
            tooltip (string): tooltip to be added to the button
        '''
        self.set_palette(Palette(text))

    def set_accelerator(self, accelerator):
        '''
        Sets keyboard shortcut that activates this button.

        Args:
            accelerator(string): accelerator to be set. Should be in
            form <modifier>Letter
            Find about format here :
            https://developer.gnome.org/gtk3/stable/gtk3-Keyboard-Accelerators.html#gtk-accelerator-parse

        Example:
            set_accelerator(self, 'accel')
        '''
        self._accelerator = accelerator
        setup_accelerator(self)

    def get_accelerator(self):
        '''
        Returns above accelerator string.
        '''
        return self._accelerator

    accelerator = GObject.property(type=str, setter=set_accelerator,
                                   getter=get_accelerator)

    def do_draw(self, cr):
        '''
        Implementation method for drawing the toogle tool button
        '''
        if self.palette and self.palette.is_up():
            allocation = self.get_allocation()
            # draw a black background, has been done by the engine before
            cr.set_source_rgb(0, 0, 0)
            cr.rectangle(0, 0, allocation.width, allocation.height)
            cr.paint()

        Gtk.ToggleToolButton.do_draw(self, cr)

        if self.palette and self.palette.is_up():
            invoker = self.palette.props.invoker
            invoker.draw_rectangle(cr, self.palette)

        return False

    def do_clicked(self):
        '''
        Implementation method for hiding the tooltip when the
        toggle button is clicked
        '''
        if self.palette:
            self.palette.popdown(True)

    palette = property(get_palette, set_palette)
