text: ﻿/*
  Copyright (c) 2003-2012, CKSource - Frederico Knabben. All rights reserved.
  For licensing, see LICENSE.html or http://ckeditor.com/license
  */
  
  /**
   * @file Insert and remove numbered and bulleted lists.
   */
  
  (function()
  {
  	var listNodeNames = { ol : 1, ul : 1 },
  		emptyTextRegex = /^[\n\r\t ]*$/;
  
  	var whitespaces = CKEDITOR.dom.walker.whitespaces(),
  		bookmarks = CKEDITOR.dom.walker.bookmark(),
  		nonEmpty = function( node ){ return !( whitespaces( node ) || bookmarks( node ) );},
  		blockBogus = CKEDITOR.dom.walker.bogus();
  
  	function cleanUpDirection( element )
  	{
  		var dir, parent, parentDir;
  		if ( ( dir = element.getDirection() ) )
  		{
  			parent = element.getParent();
  			while ( parent && !( parentDir = parent.getDirection() ) )
  				parent = parent.getParent();
  
  			if ( dir == parentDir )
  				element.removeAttribute( 'dir' );
  		}
  	}
  
  	// Inheirt inline styles from another element.
  	function inheirtInlineStyles( parent, el )
  	{
  		var style = parent.getAttribute( 'style' );
  
  		// Put parent styles before child styles.
  		style && el.setAttribute( 'style',
  			style.replace( /([^;])$/, '$1;' ) +
  			( el.getAttribute( 'style' ) || '' ) );
  	}
  
  	CKEDITOR.plugins.list = {
  		/*
  		 * Convert a DOM list tree into a data structure that is easier to
  		 * manipulate. This operation should be non-intrusive in the sense that it
  		 * does not change the DOM tree, with the exception that it may add some
  		 * markers to the list item nodes when database is specified.
  		 */
  		listToArray : function( listNode, database, baseArray, baseIndentLevel, grandparentNode )
  		{
  			if ( !listNodeNames[ listNode.getName() ] )
  				return [];
  
  			if ( !baseIndentLevel )
  				baseIndentLevel = 0;
  			if ( !baseArray )
  				baseArray = [];
  
  			// Iterate over all list items to and look for inner lists.
  			for ( var i = 0, count = listNode.getChildCount() ; i < count ; i++ )
  			{
  				var listItem = listNode.getChild( i );
  
  				// Fixing malformed nested lists by moving it into a previous list item. (#6236)
  				if( listItem.type == CKEDITOR.NODE_ELEMENT && listItem.getName() in CKEDITOR.dtd.$list )
  					CKEDITOR.plugins.list.listToArray( listItem, database, baseArray, baseIndentLevel + 1 );
  
  				// It may be a text node or some funny stuff.
  				if ( listItem.$.nodeName.toLowerCase() != 'li' )
  					continue;
  
  				var itemObj = { 'parent' : listNode, indent : baseIndentLevel, element : listItem, contents : [] };
  				if ( !grandparentNode )
  				{
  					itemObj.grandparent = listNode.getParent();
  					if ( itemObj.grandparent && itemObj.grandparent.$.nodeName.toLowerCase() == 'li' )
  						itemObj.grandparent = itemObj.grandparent.getParent();
  				}
  				else
  					itemObj.grandparent = grandparentNode;
  
  				if ( database )
  					CKEDITOR.dom.element.setMarker( database, listItem, 'listarray_index', baseArray.length );
  				baseArray.push( itemObj );
  
  				for ( var j = 0, itemChildCount = listItem.getChildCount(), child; j < itemChildCount ; j++ )
  				{
  					child = listItem.getChild( j );
  					if ( child.type == CKEDITOR.NODE_ELEMENT && listNodeNames[ child.getName() ] )
  						// Note the recursion here, it pushes inner list items with
  						// +1 indentation in the correct order.
  						CKEDITOR.plugins.list.listToArray( child, database, baseArray, baseIndentLevel + 1, itemObj.grandparent );
  					else
  						itemObj.contents.push( child );
  				}
  			}
  			return baseArray;
  		},
  
  		// Convert our internal representation of a list back to a DOM forest.
  		arrayToList : function( listArray, database, baseIndex, paragraphMode, dir )
  		{
  			if ( !baseIndex )
  				baseIndex = 0;
  			if ( !listArray || listArray.length < baseIndex + 1 )
  				return null;
  			var i,
  				doc = listArray[ baseIndex ].parent.getDocument(),
  				retval = new CKEDITOR.dom.documentFragment( doc ),
  				rootNode = null,
  				currentIndex = baseIndex,
  				indentLevel = Math.max( listArray[ baseIndex ].indent, 0 ),
  				currentListItem = null,
  				orgDir,
  				block,
  				paragraphName = ( paragraphMode == CKEDITOR.ENTER_P ? 'p' : 'div' );
  			while ( 1 )
  			{
  				var item = listArray[ currentIndex ],
  					itemGrandParent = item.grandparent;
  
  				orgDir = item.element.getDirection( 1 );
  
  				if ( item.indent == indentLevel )
  				{
  					if ( !rootNode || listArray[ currentIndex ].parent.getName() != rootNode.getName() )
  					{
  						rootNode = listArray[ currentIndex ].parent.clone( false, 1 );
  						dir && rootNode.setAttribute( 'dir', dir );
  						retval.append( rootNode );
  					}
  					currentListItem = rootNode.append( item.element.clone( 0, 1 ) );
  
  					if ( orgDir != rootNode.getDirection( 1 ) )
  						currentListItem.setAttribute( 'dir', orgDir );
  
  					for ( i = 0 ; i < item.contents.length ; i++ )
  						currentListItem.append( item.contents[i].clone( 1, 1 ) );
  					currentIndex++;
  				}
  				else if ( item.indent == Math.max( indentLevel, 0 ) + 1 )
  				{
  					// Maintain original direction (#6861).
  					var currDir = listArray[ currentIndex - 1 ].element.getDirection( 1 ),
  						listData = CKEDITOR.plugins.list.arrayToList( listArray, null, currentIndex, paragraphMode,
  						currDir != orgDir ? orgDir: null );
  
  					// If the next block is an <li> with another list tree as the first
  					// child, we'll need to append a filler (<br>/NBSP) or the list item
  					// wouldn't be editable. (#6724)
  					if ( !currentListItem.getChildCount() && CKEDITOR.env.ie && !( doc.$.documentMode > 7 ))
  						currentListItem.append( doc.createText( '\xa0' ) );
  					currentListItem.append( listData.listNode );
  					currentIndex = listData.nextIndex;
  				}
  				else if ( item.indent == -1 && !baseIndex && itemGrandParent )
  				{
  					if ( listNodeNames[ itemGrandParent.getName() ] )
  					{
  						currentListItem = item.element.clone( false, true );
  						if ( orgDir != itemGrandParent.getDirection( 1 ) )
  							currentListItem.setAttribute( 'dir', orgDir );
  					}
  					else
  						currentListItem = new CKEDITOR.dom.documentFragment( doc );
  
  					// Migrate all children to the new container,
  					// apply the proper text direction.
  					var dirLoose = itemGrandParent.getDirection( 1 ) != orgDir,
  						li = item.element,
  						className = li.getAttribute( 'class' ),
  						style = li.getAttribute( 'style' );
  
  					var needsBlock = currentListItem.type ==
  					                 CKEDITOR.NODE_DOCUMENT_FRAGMENT &&
  					                 ( paragraphMode != CKEDITOR.ENTER_BR || dirLoose ||
  					                   style || className );
  
  					var child, count = item.contents.length;
  					for ( i = 0 ; i < count; i++ )
  					{
  						child = item.contents[ i ];
  
  						if ( child.type == CKEDITOR.NODE_ELEMENT && child.isBlockBoundary() )
  						{
  							// Apply direction on content blocks.
  							if ( dirLoose && !child.getDirection() )
  								child.setAttribute( 'dir', orgDir );
  
  							inheirtInlineStyles( li, child );
  
  							className && child.addClass( className );
  						}
  						else if ( needsBlock )
  						{
  							// Establish new block to hold text direction and styles.
  							if ( !block )
  							{
  								block = doc.createElement( paragraphName );
  								dirLoose && block.setAttribute( 'dir', orgDir );
  							}
  
  							// Copy over styles to new block;
  							style && block.setAttribute( 'style', style );
  							className && block.setAttribute( 'class', className );
  
  							block.append( child.clone( 1, 1 ) );
  						}
  
  						currentListItem.append( block || child.clone( 1, 1 ) );
  					}
  
  					if ( currentListItem.type == CKEDITOR.NODE_DOCUMENT_FRAGMENT
  						 && currentIndex != listArray.length - 1 )
  					{
  						var last = currentListItem.getLast();
  						if ( last && last.type == CKEDITOR.NODE_ELEMENT
  								&& last.getAttribute( 'type' ) == '_moz' )
  						{
  							last.remove();
  						}
  
  						if ( !( last = currentListItem.getLast( nonEmpty )
  							&& last.type == CKEDITOR.NODE_ELEMENT
  							&& last.getName() in CKEDITOR.dtd.$block ) )
  						{
  							currentListItem.append( doc.createElement( 'br' ) );
  						}
  					}
  
  					var currentListItemName = currentListItem.$.nodeName.toLowerCase();
  					if ( !CKEDITOR.env.ie && ( currentListItemName == 'div' || currentListItemName == 'p' ) )
  						currentListItem.appendBogus();
  					retval.append( currentListItem );
  					rootNode = null;
  					currentIndex++;
  				}
  				else
  					return null;
  
  				block = null;
  
  				if ( listArray.length <= currentIndex || Math.max( listArray[ currentIndex ].indent, 0 ) < indentLevel )
  					break;
  			}
  
  			if ( database )
  			{
  				var currentNode = retval.getFirst(),
  					listRoot = listArray[ 0 ].parent;
  
  				while ( currentNode )
  				{
  					if ( currentNode.type == CKEDITOR.NODE_ELEMENT )
  					{
  						// Clear marker attributes for the new list tree made of cloned nodes, if any.
  						CKEDITOR.dom.element.clearMarkers( database, currentNode );
  
  						// Clear redundant direction attribute specified on list items.
  						if ( currentNode.getName() in CKEDITOR.dtd.$listItem )
  							cleanUpDirection( currentNode );
  					}
  
  					currentNode = currentNode.getNextSourceNode();
  				}
  			}
  
  			return { listNode : retval, nextIndex : currentIndex };
  		}
  	};
  
  	function onSelectionChange( evt )
  	{
  		if ( evt.editor.readOnly )
  			return null;
  
  		var path = evt.data.path,
  			blockLimit = path.blockLimit,
  			elements = path.elements,
  			element,
  			i;
  
  		// Grouping should only happen under blockLimit.(#3940).
  		for ( i = 0 ; i < elements.length && ( element = elements[ i ] )
  			  && !element.equals( blockLimit ); i++ )
  		{
  			if ( listNodeNames[ elements[ i ].getName() ] )
  				return this.setState( this.type == elements[ i ].getName() ? CKEDITOR.TRISTATE_ON : CKEDITOR.TRISTATE_OFF );
  		}
  
  		return this.setState( CKEDITOR.TRISTATE_OFF );
  	}
  
  	function changeListType( editor, groupObj, database, listsCreated )
  	{
  		// This case is easy...
  		// 1. Convert the whole list into a one-dimensional array.
  		// 2. Change the list type by modifying the array.
  		// 3. Recreate the whole list by converting the array to a list.
  		// 4. Replace the original list with the recreated list.
  		var listArray = CKEDITOR.plugins.list.listToArray( groupObj.root, database ),
  			selectedListItems = [];
  
  		for ( var i = 0 ; i < groupObj.contents.length ; i++ )
  		{
  			var itemNode = groupObj.contents[i];
  			itemNode = itemNode.getAscendant( 'li', true );
  			if ( !itemNode || itemNode.getCustomData( 'list_item_processed' ) )
  				continue;
  			selectedListItems.push( itemNode );
  			CKEDITOR.dom.element.setMarker( database, itemNode, 'list_item_processed', true );
  		}
  
  		var root = groupObj.root,
  			doc = root.getDocument(),
  			listNode,
  			newListNode;
  
  		for ( i = 0 ; i < selectedListItems.length ; i++ )
  		{
  			var listIndex = selectedListItems[i].getCustomData( 'listarray_index' );
  			listNode = listArray[ listIndex ].parent;
  
  			// Switch to new list node for this particular item.
  			if ( !listNode.is( this.type ) )
  			{
  				newListNode = doc.createElement( this.type );
  				// Copy all attributes, except from 'start' and 'type'.
  				listNode.copyAttributes( newListNode, { start : 1, type : 1 } );
  				// The list-style-type property should be ignored.
  				newListNode.removeStyle( 'list-style-type' );
  				listArray[ listIndex ].parent = newListNode;
  			}
  		}
  
  		var newList = CKEDITOR.plugins.list.arrayToList( listArray, database, null, editor.config.enterMode );
  		var child, length = newList.listNode.getChildCount();
  		for ( i = 0 ; i < length && ( child = newList.listNode.getChild( i ) ) ; i++ )
  		{
  			if ( child.getName() == this.type )
  				listsCreated.push( child );
  		}
  		newList.listNode.replace( groupObj.root );
  	}
  
  	var headerTagRegex = /^h[1-6]$/;
  
  	function createList( editor, groupObj, listsCreated )
  	{
  		var contents = groupObj.contents,
  			doc = groupObj.root.getDocument(),
  			listContents = [];
  
  		// It is possible to have the contents returned by DomRangeIterator to be the same as the root.
  		// e.g. when we're running into table cells.
  		// In such a case, enclose the childNodes of contents[0] into a <div>.
  		if ( contents.length == 1 && contents[0].equals( groupObj.root ) )
  		{
  			var divBlock = doc.createElement( 'div' );
  			contents[0].moveChildren && contents[0].moveChildren( divBlock );
  			contents[0].append( divBlock );
  			contents[0] = divBlock;
  		}
  
  		// Calculate the common parent node of all content blocks.
  		var commonParent = groupObj.contents[0].getParent();
  		for ( var i = 0 ; i < contents.length ; i++ )
  			commonParent = commonParent.getCommonAncestor( contents[i].getParent() );
  
  		var useComputedState = editor.config.useComputedState,
  			listDir, explicitDirection;
  
  		useComputedState = useComputedState === undefined || useComputedState;
  
  		// We want to insert things that are in the same tree level only, so calculate the contents again
  		// by expanding the selected blocks to the same tree level.
  		for ( i = 0 ; i < contents.length ; i++ )
  		{
  			var contentNode = contents[i],
  				parentNode;
  			while ( ( parentNode = contentNode.getParent() ) )
  			{
  				if ( parentNode.equals( commonParent ) )
  				{
  					listContents.push( contentNode );
  
  					// Determine the lists's direction.
  					if ( !explicitDirection && contentNode.getDirection() )
  						explicitDirection = 1;
  
  					var itemDir = contentNode.getDirection( useComputedState );
  
  					if ( listDir !== null )
  					{
  						// If at least one LI have a different direction than current listDir, we can't have listDir.
  						if ( listDir && listDir != itemDir )
  							listDir = null;
  						else
  							listDir = itemDir;
  					}
  
  					break;
  				}
  				contentNode = parentNode;
  			}
  		}
  
  		if ( listContents.length < 1 )
  			return;
  
  		// Insert the list to the DOM tree.
  		var insertAnchor = listContents[ listContents.length - 1 ].getNext(),
  			listNode = doc.createElement( this.type );
  
  		listsCreated.push( listNode );
  
  		var contentBlock, listItem;
  
  		while ( listContents.length )
  		{
  			contentBlock = listContents.shift();
  			listItem = doc.createElement( 'li' );
  
  			// Preserve preformat block and heading structure when converting to list item. (#5335) (#5271)
  			if ( contentBlock.is( 'pre' ) || headerTagRegex.test( contentBlock.getName() ) )
  				contentBlock.appendTo( listItem );
  			else
  			{
  				contentBlock.copyAttributes( listItem );
  				// Remove direction attribute after it was merged into list root. (#7657)
  				if ( listDir && contentBlock.getDirection() )
  				{
  					listItem.removeStyle( 'direction' );
  					listItem.removeAttribute( 'dir' );
  				}
  				contentBlock.moveChildren( listItem );
  				contentBlock.remove();
  			}
  
  			listItem.appendTo( listNode );
  		}
  
  		// Apply list root dir only if it has been explicitly declared.
  		if ( listDir && explicitDirection )
  			listNode.setAttribute( 'dir', listDir );
  
  		if ( insertAnchor )
  			listNode.insertBefore( insertAnchor );
  		else
  			listNode.appendTo( commonParent );
  	}
  
  	function removeList( editor, groupObj, database )
  	{
  		// This is very much like the change list type operation.
  		// Except that we're changing the selected items' indent to -1 in the list array.
  		var listArray = CKEDITOR.plugins.list.listToArray( groupObj.root, database ),
  			selectedListItems = [];
  
  		for ( var i = 0 ; i < groupObj.contents.length ; i++ )
  		{
  			var itemNode = groupObj.contents[i];
  			itemNode = itemNode.getAscendant( 'li', true );
  			if ( !itemNode || itemNode.getCustomData( 'list_item_processed' ) )
  				continue;
  			selectedListItems.push( itemNode );
  			CKEDITOR.dom.element.setMarker( database, itemNode, 'list_item_processed', true );
  		}
  
  		var lastListIndex = null;
  		for ( i = 0 ; i < selectedListItems.length ; i++ )
  		{
  			var listIndex = selectedListItems[i].getCustomData( 'listarray_index' );
  			listArray[listIndex].indent = -1;
  			lastListIndex = listIndex;
  		}
  
  		// After cutting parts of the list out with indent=-1, we still have to maintain the array list
  		// model's nextItem.indent <= currentItem.indent + 1 invariant. Otherwise the array model of the
  		// list cannot be converted back to a real DOM list.
  		for ( i = lastListIndex + 1 ; i < listArray.length ; i++ )
  		{
  			if ( listArray[i].indent > listArray[i-1].indent + 1 )
  			{
  				var indentOffset = listArray[i-1].indent + 1 - listArray[i].indent;
  				var oldIndent = listArray[i].indent;
  				while ( listArray[i] && listArray[i].indent >= oldIndent )
  				{
  					listArray[i].indent += indentOffset;
  					i++;
  				}
  				i--;
  			}
  		}
  
  		var newList = CKEDITOR.plugins.list.arrayToList( listArray, database, null, editor.config.enterMode,
  			groupObj.root.getAttribute( 'dir' ) );
  
  		// Compensate <br> before/after the list node if the surrounds are non-blocks.(#3836)
  		var docFragment = newList.listNode, boundaryNode, siblingNode;
  		function compensateBrs( isStart )
  		{
  			if ( ( boundaryNode = docFragment[ isStart ? 'getFirst' : 'getLast' ]() )
  				 && !( boundaryNode.is && boundaryNode.isBlockBoundary() )
  				 && ( siblingNode = groupObj.root[ isStart ? 'getPrevious' : 'getNext' ]
  				      ( CKEDITOR.dom.walker.whitespaces( true ) ) )
  				 && !( siblingNode.is && siblingNode.isBlockBoundary( { br : 1 } ) ) )
  				editor.document.createElement( 'br' )[ isStart ? 'insertBefore' : 'insertAfter' ]( boundaryNode );
  		}
  		compensateBrs( true );
  		compensateBrs();
  
  		docFragment.replace( groupObj.root );
  	}
  
  	function listCommand( name, type )
  	{
  		this.name = name;
  		this.type = type;
  	}
  
  	var elementType = CKEDITOR.dom.walker.nodeType( CKEDITOR.NODE_ELEMENT );
  
  	// Merge child nodes with direction preserved. (#7448)
  	function mergeChildren( from, into, refNode, forward )
  	{
  		var child, itemDir;
  		while ( ( child = from[ forward ? 'getLast' : 'getFirst' ]( elementType ) ) )
  		{
  			if ( ( itemDir = child.getDirection( 1 ) ) !== into.getDirection( 1 ) )
  				child.setAttribute( 'dir', itemDir );
  
  			child.remove();
  
  			refNode ?
  				child[ forward ? 'insertBefore' : 'insertAfter' ]( refNode ) :
  				into.append( child, forward  );
  		}
  	}
  
  	listCommand.prototype = {
  		exec : function( editor )
  		{
  			var doc = editor.document,
  				config = editor.config,
  				selection = editor.getSelection(),
  				ranges = selection && selection.getRanges( true );
  
  			// There should be at least one selected range.
  			if ( !ranges || ranges.length < 1 )
  				return;
  
  			// Midas lists rule #1 says we can create a list even in an empty document.
  			// But DOM iterator wouldn't run if the document is really empty.
  			// So create a paragraph if the document is empty and we're going to create a list.
  			if ( this.state == CKEDITOR.TRISTATE_OFF )
  			{
  				var body = doc.getBody();
  				if ( !body.getFirst( nonEmpty ) )
  				{
  					config.enterMode == CKEDITOR.ENTER_BR ?
  						body.appendBogus() :
  						ranges[ 0 ].fixBlock( 1, config.enterMode == CKEDITOR.ENTER_P ? 'p' : 'div' );
  
  					selection.selectRanges( ranges );
  				}
  				// Maybe a single range there enclosing the whole list,
  				// turn on the list state manually(#4129).
  				else
  				{
  					var range = ranges.length == 1 && ranges[ 0 ],
  						enclosedNode = range && range.getEnclosedNode();
  					if ( enclosedNode && enclosedNode.is
  						&& this.type == enclosedNode.getName() )
  							this.setState( CKEDITOR.TRISTATE_ON );
  				}
  			}
  
  			var bookmarks = selection.createBookmarks( true );
  
  			// Group the blocks up because there are many cases where multiple lists have to be created,
  			// or multiple lists have to be cancelled.
  			var listGroups = [],
  				database = {},
  				rangeIterator = ranges.createIterator(),
  				index = 0;
  
  			while ( ( range = rangeIterator.getNextRange() ) && ++index )
  			{
  				var boundaryNodes = range.getBoundaryNodes(),
  					startNode = boundaryNodes.startNode,
  					endNode = boundaryNodes.endNode;
  
  				if ( startNode.type == CKEDITOR.NODE_ELEMENT && startNode.getName() == 'td' )
  					range.setStartAt( boundaryNodes.startNode, CKEDITOR.POSITION_AFTER_START );
  
  				if ( endNode.type == CKEDITOR.NODE_ELEMENT && endNode.getName() == 'td' )
  					range.setEndAt( boundaryNodes.endNode, CKEDITOR.POSITION_BEFORE_END );
  
  				var iterator = range.createIterator(),
  					block;
  
  				iterator.forceBrBreak = ( this.state == CKEDITOR.TRISTATE_OFF );
  
  				while ( ( block = iterator.getNextParagraph() ) )
  				{
  					// Avoid duplicate blocks get processed across ranges.
  					if( block.getCustomData( 'list_block' ) )
  						continue;
  					else
  						CKEDITOR.dom.element.setMarker( database, block, 'list_block', 1 );
  
  					var path = new CKEDITOR.dom.elementPath( block ),
  						pathElements = path.elements,
  						pathElementsCount = pathElements.length,
  						listNode = null,
  						processedFlag = 0,
  						blockLimit = path.blockLimit,
  						element;
  
  					// First, try to group by a list ancestor.
  					for ( var i = pathElementsCount - 1; i >= 0 && ( element = pathElements[ i ] ); i-- )
  					{
  						if ( listNodeNames[ element.getName() ]
  							 && blockLimit.contains( element ) )     // Don't leak outside block limit (#3940).
  						{
  							// If we've encountered a list inside a block limit
  							// The last group object of the block limit element should
  							// no longer be valid. Since paragraphs after the list
  							// should belong to a different group of paragraphs before
  							// the list. (Bug #1309)
  							blockLimit.removeCustomData( 'list_group_object_' + index );
  
  							var groupObj = element.getCustomData( 'list_group_object' );
  							if ( groupObj )
  								groupObj.contents.push( block );
  							else
  							{
  								groupObj = { root : element, contents : [ block ] };
  								listGroups.push( groupObj );
  								CKEDITOR.dom.element.setMarker( database, element, 'list_group_object', groupObj );
  							}
  							processedFlag = 1;
  							break;
  						}
  					}
  
  					if ( processedFlag )
  						continue;
  
  					// No list ancestor? Group by block limit, but don't mix contents from different ranges.
  					var root = blockLimit;
  					if ( root.getCustomData( 'list_group_object_' + index ) )
  						root.getCustomData( 'list_group_object_' + index ).contents.push( block );
  					else
  					{
  						groupObj = { root : root, contents : [ block ] };
  						CKEDITOR.dom.element.setMarker( database, root, 'list_group_object_' + index, groupObj );
  						listGroups.push( groupObj );
  					}
  				}
  			}
  
  			// Now we have two kinds of list groups, groups rooted at a list, and groups rooted at a block limit element.
  			// We either have to build lists or remove lists, for removing a list does not makes sense when we are looking
  			// at the group that's not rooted at lists. So we have three cases to handle.
  			var listsCreated = [];
  			while ( listGroups.length > 0 )
  			{
  				groupObj = listGroups.shift();
  				if ( this.state == CKEDITOR.TRISTATE_OFF )
  				{
  					if ( listNodeNames[ groupObj.root.getName() ] )
  						changeListType.call( this, editor, groupObj, database, listsCreated );
  					else
  						createList.call( this, editor, groupObj, listsCreated );
  				}
  				else if ( this.state == CKEDITOR.TRISTATE_ON && listNodeNames[ groupObj.root.getName() ] )
  					removeList.call( this, editor, groupObj, database );
  			}
  
  			// For all new lists created, merge into adjacent, same type lists.
  			for ( i = 0 ; i < listsCreated.length ; i++ )
  				mergeListSiblings( listsCreated[ i ] );
  
  			// Clean up, restore selection and update toolbar button states.
  			CKEDITOR.dom.element.clearAllMarkers( database );
  			selection.selectBookmarks( bookmarks );
  			editor.focus();
  		}
  	};
  
  	// Merge list adjacent, of same type lists.
  	function mergeListSiblings( listNode )
  	{
  		var mergeSibling;
  		( mergeSibling = function( rtl )
  		{
  			var sibling = listNode[ rtl ? 'getPrevious' : 'getNext' ]( nonEmpty );
  			if ( sibling && sibling.type == CKEDITOR.NODE_ELEMENT &&
  			     sibling.is( listNode.getName() ) )
  			{
  				// Move children order by merge direction.(#3820)
  				mergeChildren( listNode, sibling, null, !rtl );
  
  				listNode.remove();
  				listNode = sibling;
  			}
  		} )();
  		mergeSibling( 1 );
  	}
  
  	var dtd = CKEDITOR.dtd;
  	var tailNbspRegex = /[\t\r\n ]*(?:&nbsp;|\xa0)$/;
  
  	function indexOfFirstChildElement( element, tagNameList )
  	{
  		var child,
  			children = element.children,
  			length = children.length;
  
  		for ( var i = 0 ; i < length ; i++ )
  		{
  			child = children[ i ];
  			if ( child.name && ( child.name in tagNameList ) )
  				return i;
  		}
  
  		return length;
  	}
  
  	function getExtendNestedListFilter( isHtmlFilter )
  	{
  		// An element filter function that corrects nested list start in an empty
  		// list item for better displaying/outputting. (#3165)
  		return function( listItem )
  		{
  			var children = listItem.children,
  				firstNestedListIndex = indexOfFirstChildElement( listItem, dtd.$list ),
  				firstNestedList = children[ firstNestedListIndex ],
  				nodeBefore = firstNestedList && firstNestedList.previous,
  				tailNbspmatch;
  
  			if ( nodeBefore
  				&& ( nodeBefore.name && nodeBefore.name == 'br'
  					|| nodeBefore.value && ( tailNbspmatch = nodeBefore.value.match( tailNbspRegex ) ) ) )
  			{
  				var fillerNode = nodeBefore;
  
  				// Always use 'nbsp' as filler node if we found a nested list appear
  				// in front of a list item.
  				if ( !( tailNbspmatch && tailNbspmatch.index ) && fillerNode == children[ 0 ] )
  					children[ 0 ] = ( isHtmlFilter || CKEDITOR.env.ie ) ?
  					                 new CKEDITOR.htmlParser.text( '\xa0' ) :
  									 new CKEDITOR.htmlParser.element( 'br', {} );
  
  				// Otherwise the filler is not needed anymore.
  				else if ( fillerNode.name == 'br' )
  					children.splice( firstNestedListIndex - 1, 1 );
  				else
  					fillerNode.value = fillerNode.value.replace( tailNbspRegex, '' );
  			}
  
  		};
  	}
  
  	var defaultListDataFilterRules = { elements : {} };
  	for ( var i in dtd.$listItem )
  		defaultListDataFilterRules.elements[ i ] = getExtendNestedListFilter();
  
  	var defaultListHtmlFilterRules = { elements : {} };
  	for ( i in dtd.$listItem )
  		defaultListHtmlFilterRules.elements[ i ] = getExtendNestedListFilter( true );
  
  	// Check if node is block element that recieves text.
  	function isTextBlock( node )
  	{
  		return node.type == CKEDITOR.NODE_ELEMENT &&
  			   ( node.getName() in CKEDITOR.dtd.$block ||
  				 node.getName() in CKEDITOR.dtd.$listItem ) &&
  			   CKEDITOR.dtd[ node.getName() ][ '#' ];
  	}
  
  	// Merge the visual line content at the cursor range into the block.
  	function joinNextLineToCursor( editor, cursor, nextCursor )
  	{
  		editor.fire( 'saveSnapshot' );
  
  		// Merge with previous block's content.
  		nextCursor.enlarge( CKEDITOR.ENLARGE_LIST_ITEM_CONTENTS );
  		var frag = nextCursor.extractContents();
  
  		cursor.trim( false, true );
  		var bm = cursor.createBookmark();
  
  		// Kill original bogus;
  		var currentPath = new CKEDITOR.dom.elementPath( cursor.startContainer );
  		var currentLi = currentPath.lastElement.getAscendant( 'li', 1 );
  
  		var bogus = currentPath.block.getBogus();
  		bogus && bogus.remove();
  
  		// Kill the tail br in extracted.
  		var last = frag.getLast();
  		if ( last && last.type == CKEDITOR.NODE_ELEMENT && last.is( 'br' ) )
  			last.remove();
  
  		// Insert fragment at the range position.
  		var nextNode = cursor.startContainer.getChild( cursor.startOffset );
  		if ( nextNode )
  			frag.insertBefore( nextNode );
  		else
  			cursor.startContainer.append( frag );
  
  		var nextPath = new CKEDITOR.dom.elementPath( nextCursor.startContainer );
  		var nextLi = nextCursor.startContainer.getAscendant( 'li', 1 );
  
  		// Move the sub list nested in the next list item.
  		if ( nextLi )
  		{
  			var sublist = getSubList( nextLi );
  			if ( sublist )
  			{
  				// If next line is in the sub list of the current list item.
  				if ( currentLi.contains( nextLi ) )
  				{
  					mergeChildren( sublist, nextLi.getParent(), nextLi );
  					sublist.remove();
  				}
  				// Migrate the sub list to current list item.
  				else
  					currentLi.append( sublist );
  			}
  		}
  
  		// Remove any remaining empty path blocks at next line after merging.
  		while ( nextCursor.checkStartOfBlock() &&
  			 nextCursor.checkEndOfBlock() )
  		{
  			nextPath = new CKEDITOR.dom.elementPath( nextCursor.startContainer );
  			var nextBlock = nextPath.block, parent;
  
  			// Check if also to remove empty list.
  			if ( nextBlock.is( 'li' ) )
  			{
  				parent = nextBlock.getParent();
  				if ( nextBlock.equals( parent.getLast( nonEmpty ) )
  						&& nextBlock.equals( parent.getFirst( nonEmpty ) ) )
  					nextBlock = parent;
  			}
  
  			nextCursor.moveToPosition( nextBlock, CKEDITOR.POSITION_BEFORE_START );
  			nextBlock.remove();
  		}
  
  		// Check if need to further merge with the list resides after the merged block. (#9080)
  		var walkerRng = nextCursor.clone(), body = editor.document.getBody();
  		walkerRng.setEndAt( body, CKEDITOR.POSITION_BEFORE_END );
  		var walker = new CKEDITOR.dom.walker( walkerRng );
  		walker.evaluator = function( node ) { return nonEmpty( node ) && !blockBogus( node ); };
  		var next = walker.next();
  		if ( next && next.type == CKEDITOR.NODE_ELEMENT && next.getName() in CKEDITOR.dtd.$list )
  			mergeListSiblings( next );
  
  		cursor.moveToBookmark( bm );
  
  		// Make fresh selection.
  		cursor.select();
  
  		editor.selectionChange( 1 );
  		editor.fire( 'saveSnapshot' );
  	}
  
  	function getSubList( li )
  	{
  		var last = li.getLast( nonEmpty );
  		return last && last.type == CKEDITOR.NODE_ELEMENT && last.getName() in listNodeNames ? last : null;
  	}
  
  	CKEDITOR.plugins.add( 'list',
  	{
  		init : function( editor )
  		{
  			// Register commands.
  			var numberedListCommand = editor.addCommand( 'numberedlist', new listCommand( 'numberedlist', 'ol' ) ),
  				bulletedListCommand = editor.addCommand( 'bulletedlist', new listCommand( 'bulletedlist', 'ul' ) );
  
  			// Register the toolbar button.
  			editor.ui.addButton( 'NumberedList',
  				{
  					label : editor.lang.numberedlist,
  					command : 'numberedlist'
  				} );
  			editor.ui.addButton( 'BulletedList',
  				{
  					label : editor.lang.bulletedlist,
  					command : 'bulletedlist'
  				} );
  
  			// Register the state changing handlers.
  			editor.on( 'selectionChange', CKEDITOR.tools.bind( onSelectionChange, numberedListCommand ) );
  			editor.on( 'selectionChange', CKEDITOR.tools.bind( onSelectionChange, bulletedListCommand ) );
  
  				// Handled backspace/del key to join list items. (#8248,#9080)
  				editor.on( 'key', function( evt )
  				{
  					var key = evt.data.keyCode;
  
  					// DEl/BACKSPACE
  					if ( editor.mode == 'wysiwyg' && key in { 8 : 1, 46 : 1 } )
  					{
  						var sel = editor.getSelection(),
  						range = sel.getRanges()[ 0 ];
  
  						if ( !range.collapsed )
  							return;
  
  						var isBackspace = key == 8;
  						var body = editor.document.getBody();
  						var walker = new CKEDITOR.dom.walker( range.clone() );
  						walker.evaluator = function( node ) { return nonEmpty( node ) && !blockBogus( node ); };
  
  						var cursor = range.clone();
  
  						if ( isBackspace )
  						{
  							var previous, joinWith;
  
  							var path = new CKEDITOR.dom.elementPath( range.startContainer );
  
  							// Join a sub list's first line, with the previous visual line in parent.
  							if ( ( previous = path.contains( listNodeNames ) ) &&
  							     range.checkBoundaryOfElement( previous, CKEDITOR.START ) &&
  							     ( previous = previous.getParent() ) && previous.is( 'li' ) &&
  							     ( previous = getSubList( previous ) ) )
  							{
  								joinWith = previous;
  								previous = previous.getPrevious( nonEmpty );
  								// Place cursor before the nested list.
  								cursor.moveToPosition(
  									previous && blockBogus( previous ) ? previous : joinWith,
  									CKEDITOR.POSITION_BEFORE_START );
  							}
  							// Join any line following a list, with the last visual line of the list.
  							else
  							{
  								walker.range.setStartAt( body, CKEDITOR.POSITION_AFTER_START );
  								walker.range.setEnd( range.startContainer, range.startOffset );
  								previous = walker.previous();
  
  								if ( previous && previous.type == CKEDITOR.NODE_ELEMENT &&
  								   ( previous.getName() in listNodeNames || previous.is( 'li' ) ) )
  								{
  									if ( !previous.is( 'li' ) )
  									{
  										walker.range.selectNodeContents( previous );
  										walker.reset();
  										walker.evaluator = isTextBlock;
  										previous = walker.previous();
  									}
  
  									joinWith = previous;
  									// Place cursor at the end of previous block.
  									cursor.moveToElementEditEnd( joinWith );
  								}
  							}
  
  							if ( joinWith )
  							{
  								joinNextLineToCursor( editor, cursor, range );
  								evt.cancel();
  							}
  						}
  						else
  						{
  							var li = range.startContainer.getAscendant( 'li', 1 );
  							if ( li )
  							{
  								walker.range.setEndAt( body, CKEDITOR.POSITION_BEFORE_END );
  
  								var last = li.getLast( nonEmpty );
  								var block = last && isTextBlock( last ) ? last : li;
  
  								// Indicate cursor at the visual end of an list item.
  								var isAtEnd = 0;
  
  								var next = walker.next();
  
  								// When list item contains a sub list.
  								if ( next && next.type == CKEDITOR.NODE_ELEMENT &&
  									 next.getName() in listNodeNames
  									 && next.equals( last ) )
  								{
  									isAtEnd = 1;
  
  									// Move to the first item in sub list.
  									next = walker.next();
  								}
  								// Right at the end of list item.
  								else if ( range.checkBoundaryOfElement( block, CKEDITOR.END ) )
  									isAtEnd = 1;
  
  
  								if ( isAtEnd && next )
  								{
  									// Put cursor range there.
  									var nextLine = range.clone();
  									nextLine.moveToElementEditStart( next );
  
  									joinNextLineToCursor( editor, cursor, nextLine );
  									evt.cancel();
  								}
  							}
  						}
  
  						// The backspace/del could potentially put cursor at a bad position,
  						// being it handled or not, check immediately the selection to have it fixed.
  						setTimeout( function() { editor.selectionChange( 1 ); } );
  					}
  				} );
  		},
  
  		afterInit : function ( editor )
  		{
  			var dataProcessor = editor.dataProcessor;
  			if ( dataProcessor )
  			{
  				dataProcessor.dataFilter.addRules( defaultListDataFilterRules );
  				dataProcessor.htmlFilter.addRules( defaultListHtmlFilterRules );
  			}
  		},
  
  		requires : [ 'domiterator' ]
  	} );
  })();
  