# Copyright (c) 2015-2016 Ruby-GNOME2 Project Team
# This program is licenced under the same licence as Ruby-GNOME2.
#
=begin
=  Menus

 There are several widgets involved in displaying menus. The
 GtkMenuBar widget is a menu bar, which normally appears horizontally
 at the top of an application, but can also be layed out vertically.
 The GtkMenu widget is the actual menu that pops up. Both GtkMenuBar
 and GtkMenu are subclasses of GtkMenuShell; a GtkMenuShell contains
 menu items (GtkMenuItem). Each menu item contains text and/or images
 and can be selected by the user.

 There are several kinds of menu item, including plain GtkMenuItem,
 GtkCheckMenuItem which can be checked/unchecked, GtkRadioMenuItem
 which is a check menu item that's in a mutually exclusive group,
 GtkSeparatorMenuItem which is a separator bar, GtkTearoffMenuItem
 which allows a GtkMenu to be torn off, and GtkImageMenuItem which
 can place a GtkImage or other widget next to the menu text.

 A GtkMenuItem can have a submenu, which is simply a GtkMenu to pop
 up when the menu item is selected. Typically, all menu items in a menu bar
 have submenus.
=end
class MenusDemo
  def initialize(main_window)
    @window = Gtk::Window.new(:toplevel)
    @window.screen = main_window.screen
    @window.title = "Menus"
    @window.border_width = 0

    accel_group = Gtk::AccelGroup.new
    @window.add_accel_group(accel_group)

    box = Gtk::Box.new(:horizontal, 0)
    @window.add(box)

    box1 = Gtk::Box.new(:horizontal, 0)
    box.add(box1)

    @menubar = Gtk::MenuBar.new
    @menubar.expand = true
    box1.pack_start(@menubar, :expand => false, :fill => true, :padding => 0)

    { "test\nline2" => 2, "foo" => 3, "bar" => 4 }.each do |k, v|
      create_menu_item(k, v)
    end

    box2 = Gtk::Box.new(:vertical, 10)
    box2.border_width = 10
    box1.pack_start(box2, :expand => false, :fill => true, :padding => 0)

    button = generate_flip_button
    box2.pack_start(button, :expand => true, :fill => true, :padding => 0)
    button = generate_close_button
    box2.pack_start(button, :expand => true, :fill => true, :padding => 0)
  end

  def run
    if !@window.visible?
      @window.show_all
    else
      @window.destroy
    end
    @window
  end

  private

  def create_menu(depth)
    return nil if depth < 1

    menu = Gtk::Menu.new
    last_item = nil
    (0..5).each do |i|
      j = i + 1
      label = "item #{depth} - #{j}"
      menu_item = Gtk::RadioMenuItem.new(nil, label)
      menu_item.join_group(last_item) if last_item
      last_item = menu_item
      menu.append(menu_item)
      menu_item.sensitive = false if i == 3
      menu_item.submenu = create_menu(depth - 1)
    end

    menu
  end

  def create_menu_item(label, depth)
    menuitem = Gtk::MenuItem.new(:label => label)
    menuitem.submenu = create_menu(depth)
    @menubar.append(menuitem)
  end

  def generate_flip_button
    button = Gtk::Button.new(:label => "Flip")
    button.signal_connect("clicked") do |_widget|
      parent = @menubar.parent
      orientation = parent.orientation.to_i
      parent.orientation = 1 - orientation

      if orientation == Gtk::Orientation::VERTICAL
        @menubar.set_property("pack-direction", Gtk::PackDirection::TTB)
      else
        @menubar.set_property("pack-direction", Gtk::PackDirection::LTR)
      end
    end

    button
  end

  def generate_close_button
    button = Gtk::Button.new(:label => "Close")
    button.signal_connect("clicked") { @window.destroy }
    button.can_default = true
    button.grab_default
    button
  end
end
