var dropMenu = Class.create();
dropMenu.prototype =
{
	initialize: function(div_id, container_class, dropper_id)
	{

		this.menu_source = $('source_menu_container');
		this.menu_destination = $('msr');
		this.menu_destination.innerHTML = this.menu_source.innerHTML;
		Element.remove(this.menu_source);
		Element.addClassName(this.menu_destination,'msr');
		this.menu_source = null;

		this.menu_container = $(div_id);
		if( ! this.menu_container ) return false;
		Element.addClassName( this.menu_container, 'absolute');
		Element.addClassName( this.menu_container, 'menu_container');
		Element.addClassName( this.menu_container, 'hidden_element');

		var drop_menu_object_copy = this;

		this.dropper = $(dropper_id);
		Element.addClassName( this.dropper, 'menu_dropper');

		this.all_menus = $A(this.menu_container.getElementsByTagName('div'));

		this.temp_array = new Array();
		this.temp_index = 0;

		this.containers = new Array();
		this.openers = new Array();
		this.selected_branch = -1;

		for( var i=0; i<this.all_menus.length; i++)
		{
			if( this.all_menus[i].id )
			{
				this.matches = this.all_menus[i].id.split('_');

				if( this.matches[0].indexOf('sub') != -1 )
				{
					if( typeof( this.containers[ this.matches[1] ] ) != 'object' )
					{
						this.containers[ this.matches[1] ] = new Array();
					}
					this.containers[ this.matches[1] ][ this.matches[2] - 1 ] = this.all_menus[i].id;
					Element.addClassName( this.all_menus[i], 'absolute');
				}
				else
				{
					if( typeof( this.openers[ this.matches[1] ] ) != 'object' )
					{
						this.openers[ this.matches[1] ] = new Array();
					}
					this.openers[ this.matches[1] ][ this.matches[2] - 1 ] = this.all_menus[i].id;
					Element.addClassName( this.all_menus[i], 'float');
				}
				this.matches = null;
			}

			if ( this.all_menus[i].className.indexOf(container_class) == -1 )
			{
				this.temp_array[this.temp_index] = this.all_menus[i];
				this.temp_index++;
			}
		}
		this.all_menus = this.temp_array;

// set up mouse listeners for the main menu container
		Event.observe(this.menu_container, 'mouseover', function(event) { Element.removeClassName(div_id,'hidden_element') ; });
		Event.observe(this.menu_container, 'mouseout', function(event) { Element.addClassName(div_id,'hidden_element') ; });

// Changing background color for all menu elements
		for( var i=0; i< this.all_menus.length; i++)
		{
			Event.observe
			(
				this.all_menus[i],
				'mouseover',
				function(event)
				{
					some_obj = ( Event.element(event).tagName == 'A' ) ? Event.element(event).parentNode : Event.element(event);
					drop_menu_object_copy.setBG(some_obj,1);
					some_id = ( some_obj.id ) ? some_obj.id : ( (some_obj.parentNode) ? some_obj.parentNode.id : '' );
					if( some_id && some_id != div_id )
					{
						this.matches = some_id.split('_');
						if( this.matches ) drop_menu_object_copy.showMenu( this.matches[1],this.matches[2] );
					}
					if( some_id == div_id )
					{
						drop_menu_object_copy.closeAll();
					}
					return true;
				}
			);

			Event.observe
			(
				this.all_menus[i],
				'mouseout',
				function(event)
				{
					some_obj = ( Event.element(event).tagName == 'A' ) ? Event.element(event).parentNode : Event.element(event);
					drop_menu_object_copy.setBG(some_obj);
					some_id = ( some_obj.id ) ? some_obj.id : ( (some_obj.parentNode) ? some_obj.parentNode.id : '' );
					if( some_id && some_id != div_id )
					{
						this.matches = some_id.split('_');
						if( this.matches ) drop_menu_object_copy.closeMenu( this.matches[1],this.matches[2] );
					}
					return true;
				}
			);

			Event.observe
			(
				this.all_menus[i],
				'click',
				function(event)
				{
					if( Event.element(event).firstChild && Event.element(event).firstChild.tagName == 'A' && Event.element(event).firstChild.href != '' )
					{
						drop_menu_object_copy.closeAll();
						Element.addClassName( drop_menu_object_copy.dropper, 'hidden' );
						document.location.href = Event.element(event).firstChild.href ;
					}
					if( Event.element(event).tagName == 'A' && Event.element(event).href != '' )
					{
						drop_menu_object_copy.closeAll();
						Element.addClassName( drop_menu_object_copy.dropper, 'hidden' );
					}
					return true;
				}
			);

		}
		this.all_menus = null;
		this.temp_array = null;
		this.temp_index = null;

// set up mouse listener for the dropper
		Event.observe
		(
			this.dropper,
			'mouseover',
			function(event)
			{
				if( document.styleSheets[0].disabled )
				{
					//alert('В Вашем браузере отключена поддержка стилей CSS!\nДля правильного отображения меню Вам необходимо включить стили!');
					return false;
				}
				drop_menu_object_copy.closeAll();
				Element.removeClassName(div_id,'hidden_element');
				return true;
			}
		);
		Event.observe
		(
			this.dropper,
			'mouseout',
			function(event)
			{
				Element.addClassName(div_id,'hidden_element');
				return true;
			}
		);

		return true;
	},

	showMenu: function(branch_index, menu_level)
	{
		if( this.selected_branch == -1 )
		{
			this.selected_branch = branch_index;
		}
		if( this.selected_branch != branch_index )
		{
			this.closeAll(this.selected_branch);
			this.selected_branch = branch_index;
		}
		for( var i=0; i < menu_level; i++)
		{
			if( Element.hasClassName(this.containers[branch_index][i]), 'hidden_element' )
			{
				Element.removeClassName(this.containers[branch_index][i],'hidden_element');
				this.setBG(this.openers[branch_index][i],1);
			}
		}
		return true;
	},

	closeMenu: function(branch_index, menu_level)
	{
		for( var i= menu_level-1; i<this.containers[branch_index].length; i++)
		{
			Element.addClassName( this.containers[branch_index][i], 'hidden_element');
		}
		return true;
	},

	closeAll: function( branch_number )
	{
		if( typeof (branch_number) == 'undefined')
		{
			for( var i=0; i< this.containers.length; i++)
			{
				for( var j=0; j< this.containers[i].length; j++)
				{
					Element.addClassName( this.containers[i][j],'hidden_element' ) ;
					this.setBG(this.openers[i][j]);
				}
			}
			Element.addClassName(this.menu_container,'hidden_element');
		}
		else
		{
			for( var k=0; k< this.containers[branch_number].length; k++)
			{
				Element.addClassName( this.containers[branch_number][k], 'hidden_element' ) ;
				this.setBG(this.openers[branch_number][k]);
			}
		}
		return true;
	},

	setBG: function(some_obj_id, is_over )
	{
		//$(some_obj_id).style.backgroundColor = (is_over ) ? '#D1E3FA' : 'white';
		if( is_over )
		{
			Element.addClassName(some_obj_id,'over');
		}
		else
		{
			Element.removeClassName(some_obj_id,'over');
		}
		return true;
	}
};