using System;
using Gdk;
using GLib;
using Gtk;

namespace DMX2
{
	public class ContextMenuEventArgs : EventArgs
	{
		private Widget widget;

		public Widget Widget { get { return widget; } }

		private bool rightClick;

		public bool RightClick { get { return rightClick; } }

		public ContextMenuEventArgs (Widget widget, bool rightClick)
		{
			this.widget = widget;
			this.rightClick = rightClick;
		}
	}

	public class ContextMenuHelper
	{
		public event EventHandler<ContextMenuEventArgs> ContextMenu;

		public ContextMenuHelper ()
		{
		}

		public ContextMenuHelper (Widget widget)
		{
			AttachToWidget (widget);
		}

		public ContextMenuHelper (Widget widget, EventHandler<ContextMenuEventArgs>  handler)
		{
			AttachToWidget (widget);
			ContextMenu += handler;
		}

		public void AttachToWidget (Widget widget)
		{
			widget.PopupMenu += Widget_PopupMenu;
			widget.ButtonPressEvent += Widget_ButtonPressEvent;
		}

		public void DetachFromWidget (Widget widget)
		{
			widget.PopupMenu -= Widget_PopupMenu;
			widget.ButtonPressEvent -= Widget_ButtonPressEvent;
		}

		[GLib.ConnectBefore]
		private void Widget_PopupMenu (object o, PopupMenuArgs args)
		{
			RaiseContextMenuEvent (args, (Widget)o, false);
		}

		[GLib.ConnectBefore]
		private void Widget_ButtonPressEvent (object o, ButtonPressEventArgs args)
		{
			if (args.Event.Button == 3 && args.Event.Type == EventType.ButtonPress) {
				RaiseContextMenuEvent (args, (Widget)o, true);
			}
		}

		private bool propagating = false;   //Prevent reentry

		private void RaiseContextMenuEvent (SignalArgs signalArgs, Widget widget, bool rightClick)
		{
			if (!propagating) {
//Propagate the event
				Event evnt = Gtk.Global.CurrentEvent;
				propagating = true;
				Gtk.Global.PropagateEvent (widget, evnt);
				propagating = false;
				signalArgs.RetVal = true;     //The widget already processed the event in the propagation

//Raise the context menu event
				ContextMenuEventArgs args = new ContextMenuEventArgs (widget, rightClick);
				if (ContextMenu != null) {
					ContextMenu.Invoke (this, args);
				}
			}
		}
	}
}