/*
Copyright (c) 2003-2012, CKSource - Frederico Knabben. All rights reserved.
For licensing, see LICENSE.html or http://ckeditor.com/license
*/

CKEDITOR.plugins.add( 'removeformat',
{
	requires : [ 'selection' ],

	init : function( editor )
	{
		editor.addCommand( 'removeFormat', CKEDITOR.plugins.removeformat.commands.removeformat );
		editor.ui.addButton( 'RemoveFormat',
			{
				label : editor.lang.removeFormat,
				command : 'removeFormat'
			});

		editor._.removeFormat = { filters: [] };
	}
});

CKEDITOR.plugins.removeformat =
{
	commands :
	{
		removeformat :
		{
			exec : function( editor )
			{
				var tagsRegex = editor._.removeFormatRegex ||
					( editor._.removeFormatRegex = new RegExp( '^(?:' + editor.config.removeFormatTags.replace( /,/g,'|' ) + ')$', 'i' ) );

				var removeAttributes = editor._.removeAttributes ||
					( editor._.removeAttributes = editor.config.removeFormatAttributes.split( ',' ) );

				var filter = CKEDITOR.plugins.removeformat.filter;
				var ranges = editor.getSelection().getRanges( 1 ),
					iterator = ranges.createIterator(),
					range;

				while ( ( range = iterator.getNextRange() ) )
				{
					if ( ! range.collapsed )
						range.enlarge( CKEDITOR.ENLARGE_ELEMENT );

					// Bookmark the range so we can re-select it after processing.
					var bookmark = range.createBookmark(),
						// The style will be applied within the bookmark boundaries.
						startNode	= bookmark.startNode,
						endNode		= bookmark.endNode,
						currentNode;

					// We need to check the selection boundaries (bookmark spans) to break
					// the code in a way that we can properly remove partially selected nodes.
					// For example, removing a <b> style from
					//		<b>This is [some text</b> to show <b>the] problem</b>
					// ... where [ and ] represent the selection, must result:
					//		<b>This is </b>[some text to show the]<b> problem</b>
					// The strategy is simple, we just break the partial nodes before the
					// removal logic, having something that could be represented this way:
					//		<b>This is </b>[<b>some text</b> to show <b>the</b>]<b> problem</b>

					var breakParent = function( node )
					{
						// Let's start checking the start boundary.
						var path = new CKEDITOR.dom.elementPath( node ),
							pathElements = path.elements;

						for ( var i = 1, pathElement ; pathElement = pathElements[ i ] ; i++ )
						{
							if ( pathElement.equals( path.block ) || pathElement.equals( path.blockLimit ) )
								break;

							// If this element can be removed (even partially).
							if ( tagsRegex.test( pathElement.getName() ) && filter( editor, pathElement ) )
								node.breakParent( pathElement );
						}
					};

					breakParent( startNode );
					if ( endNode )
					{
						breakParent( endNode );

						// Navigate through all nodes between the bookmarks.
						currentNode = startNode.getNextSourceNode( true, CKEDITOR.NODE_ELEMENT );

						while ( currentNode )
						{
							// If we have reached the end of the selection, stop looping.
							if ( currentNode.equals( endNode ) )
								break;

							// Cache the next node to be processed. Do it now, because
							// currentNode may be removed.
							var nextNode = currentNode.getNextSourceNode( false, CKEDITOR.NODE_ELEMENT );

							// This node must not be a fake element.
							if ( !( currentNode.getName() == 'img'
								&& currentNode.data( 'cke-realelement' ) )
								&& filter( editor, currentNode ) )
							{
								// Remove elements nodes that match with this style rules.
								if ( tagsRegex.test( currentNode.getName() ) )
									currentNode.remove( 1 );
								else
								{
									currentNode.removeAttributes( removeAttributes );
									editor.fire( 'removeFormatCleanup', currentNode );
								}
							}

							currentNode = nextNode;
						}
					}

					range.moveToBookmark( bookmark );
				}

				editor.getSelection().selectRanges( ranges );
			}
		}
	},

	/**
	 * Perform the remove format filters on the passed element.
	 * @param {CKEDITOR.editor} editor
	 * @param {CKEDITOR.dom.element} element
	 */
	filter : function ( editor, element )
	{
		var filters = editor._.removeFormat.filters;
		for ( var i = 0; i < filters.length; i++ )
		{
			if ( filters[ i ]( element ) === false )
				return false;
		}
		return true;
	}
};

/**
 * Add to a collection of functions to decide whether a specific
 * element should be considered as formatting element and thus
 * could be removed during <b>removeFormat</b> command,
 * Note: Only available with the existence of 'removeformat' plugin.
 * @since 3.3
 * @param {Function} func The function to be called, which will be passed a {CKEDITOR.dom.element} element to test.
 * @example
 *  // Don't remove empty span
 *  editor.addRemoveFormatFilter.push( function( element )
 *		{
 *			return !( element.is( 'span' ) && CKEDITOR.tools.isEmpty( element.getAttributes() ) );
 *		});
 */
CKEDITOR.editor.prototype.addRemoveFormatFilter = function( func )
{
	this._.removeFormat.filters.push( func );
};

/**
 * A comma separated list of elements to be removed when executing the "remove
 " format" command. Note that only inline elements are allowed.
 * @type String
 * @default 'b,big,code,del,dfn,em,font,i,ins,kbd,q,samp,small,span,strike,strong,sub,sup,tt,u,var'
 * @example
 */
CKEDITOR.config.removeFormatTags = 'b,big,code,del,dfn,em,font,i,ins,kbd,q,samp,small,span,strike,strong,sub,sup,tt,u,var';

/**
 * A comma separated list of elements attributes to be removed when executing
 * the "remove format" command.
 * @type String
 * @default 'class,style,lang,width,height,align,hspace,valign'
 * @example
 */
CKEDITOR.config.removeFormatAttributes = 'class,style,lang,width,height,align,hspace,valign';

/**
 * Fired after an element was cleaned by the removeFormat plugin.
 * @name CKEDITOR.editor#removeFormatCleanup
 * @event
 * @param {Object} data.element The element that was cleaned up.
 */