/*!
* Aloha Editor
* Author & Copyright (c) 2010 Gentics Software GmbH
* aloha-sales@gentics.com
* Licensed unter the terms of http://www.aloha-editor.com/license.html
*/
define(
['aloha', 'aloha/jquery', 'aloha/contenthandlermanager'],
function(Aloha, jQuery, ContentHandlerManager) {
	

	var
		GENTICS = window.GENTICS;

	/**
	 * Register the generic content handler
	 */
	var GenericContentHandler = ContentHandlerManager.createHandler({
		/**
		 * Handle the pasting. Remove all unwanted stuff.
		 * @param content
		 */
		handleContent: function( content ) {
			if ( typeof content === 'string' ){
				content = jQuery( '<div>' + content + '</div>' );
			} else if ( content instanceof jQuery ) {
				content = jQuery( '<div>' ).append(content);
			}

			// If we find an aloha-block inside the pasted content,
			// we do not modify the pasted stuff, as it most probably
			// comes from Aloha and not from other sources, and does
			// not need to be cleaned up.
			if (content.find('.aloha-block').length > 0) {
				return;
			}

			// clean lists
			this.cleanLists(content);

			// transform tables
			this.transformTables(content);

			// remove comments
			this.removeComments(content);

			// unwrap font and span tags
			this.unwrapTags(content);

			// remove styles
			this.removeStyles(content);

			// remove namespaced elements
			this.removeNamespacedElements(content);

			// transform formattings
			this.transformFormattings(content);

			// transform links
			//this.transformLinks(content);

			return content.html();
		},

		/**
		 * Clean lists: The only allowed children of ol or ul elements are li's. Everything else will be removed
		 * @param content
		 */
		cleanLists: function(content) {
			content.find('ul,ol').each(function() {
				var $list = jQuery(this);
				$list.contents(':not(li,ul,ol)').each(function() {
					jQuery(this).remove();
				});
				// for all li's, trim the text contents
				$list.children('li').each(function() {
					var $li = jQuery(this);
					$li.contents().each(function() {
						if (this.nodeType === 3) {
							this.data = jQuery.trim(this.data);
						}
					});
				});
			});
		},

		/**
		 * Transform tables which were pasted
		 * @param content
		 */
		transformTables: function(content) {
			// remove border, cellspacing, cellpadding from all tables
			// @todo what about width, height?
			content.find('table').each(function() {
				jQuery(this).removeAttr('border').removeAttr('cellspacing').removeAttr('cellpadding');
			});
			
			// remove unwanted attributes and cleanup single empty p-tags
			content.find('td').each(function() {
				// remove width, height and valign from all table cells
				jQuery(this).removeAttr('width').removeAttr('height').removeAttr('valign');
				
				if ( this.innerHTML.replace(/[\s\xA0]+/g,'') === '<p><br></p>' ) {
					this.innerHTML = '&nbsp;';
				}
				
				if ( jQuery(this).find('p').length == 1) {
					jQuery(this).find('p').contents().unwrap();
				}
			});
			
			// remove unwanted attributes from tr also? (tested with paste from open/libre office)
			// @todo or do this all via sanitize.js 
			content.find('tr').each(function() {
				// remove width, height and valign from all table cells
				jQuery(this).removeAttr('width').removeAttr('height').removeAttr('valign');
			});
			
			// completely colgroup tags
			// @TODO should we remove colgroup? use sanitize for that?
			content.find('colgroup').remove();
		},

		/**
		 * Transform formattings
		 * @param content
		 */
		transformFormattings: function( content ) {
			// find all formattings we will transform
			content.find('strong,em,s,u').each(function() {
				if (this.nodeName.toLowerCase() == 'strong') {
					// transform strong to b
					Aloha.Markup.transformDomObject(jQuery(this), 'b');
				} else if (this.nodeName.toLowerCase() == 'em') {
					// transform em to i
					Aloha.Markup.transformDomObject(jQuery(this), 'i');
				} else if (this.nodeName.toLowerCase() == 's') {
					// transform s to del
					Aloha.Markup.transformDomObject(jQuery(this), 'del');
				} else if (this.nodeName.toLowerCase() == 'u') {
					// transform u?
					jQuery(this).contents().unwrap();
				}
			});
		},

		/**
		 * Transform links
		 * @param content
		 */
		transformLinks: function( content ) {
			// find all links and remove the links without href (will be destination anchors from word table of contents)
			// aloha is not supporting anchors at the moment -- maybe rewrite anchors in headings to "invisible"
			// in the test document there are anchors for whole paragraphs --> the whole P appear as link
			content.find('a').each(function() {
				if ( typeof jQuery(this).attr('href') === 'undefined' ) {
					jQuery(this).contents().unwrap();
				}
			});
		},

		/**
		 * Remove all comments
		 * @param content
		 */
		removeComments: function( content ) {
			var that = this;

			// ok, remove all comments
			content.contents().each(function() {
				if (this.nodeType == 8) {
					jQuery(this).remove();
				} else {
					// do recursion
					that.removeComments(jQuery(this));
				}
			});
		},

		/**
		 * Remove some unwanted tags from content pasted
		 * @param content
		 */
		unwrapTags: function( content ) {
			var that = this;

			content.find('span,font,div').each(function() {
				if (this.nodeName == 'DIV') {
					// safari and chrome cleanup for plain text paste with working linebreaks
					if (this.innerHTML == '<br>') {
						jQuery(this).contents().unwrap();
					} else {
						jQuery( Aloha.Markup.transformDomObject(jQuery(this), 'p').append('<br>') ).contents().unwrap();
					}
				} else {
					jQuery(this).contents().unwrap();
				}
			});
		},

		/**
		 * Remove styles
		 * @param content
		 */
		removeStyles: function( content ) {
			var that = this;

			// completely remove style tags
			content.children('style').filter(function() {
				return this.contentEditable != 'false';
			}).remove();

			// remove style attributes and classes
			content.children().filter(function() {
				return this.contentEditable != 'false';
			}).each(function() {
				jQuery(this).removeAttr('style').removeClass();
				that.removeStyles(jQuery(this));
			});
		},

		/**
		 * Remove all elements which are in different namespaces
		 * @param content
		 */
		removeNamespacedElements: function( content ) {
			// get all elements
			content.find('*').each(function() {
				// try to determine the namespace prefix ('prefix' works for W3C
				// compliant browsers, 'scopeName' for IE)

				var nsPrefix = this.prefix ? this.prefix
						: (this.scopeName ? this.scopeName : undefined);
				// when the prefix is set (and different from 'HTML'), we remove the
				// element
				if ((nsPrefix && nsPrefix != 'HTML') || this.nodeName.indexOf(':') >= 0 ) {
					var $this = jQuery(this), $contents = $this.contents();
					if ($contents.length) {
						// the element has contents, so unwrap the contents
						$contents.unwrap();
					} else {
						// the element is empty, so remove it
						$this.remove();
					}
				}
			});
		}
	});

	return GenericContentHandler;
});
