/*
Copyright (c) 2003-2011, CKSource - Frederico Knabben. All rights reserved.
For licensing, see LICENSE.html or http://ckeditor.com/license
*/

/**
 * @stylesheetParser plugin.
 */

(function()
{
    // We want to extract only the elements with classes defined in the stylesheets:
    function parseClasses( aRules, skipSelectors, validSelectors )
    {
        // aRules are just the different rules in the style sheets
        // We want to merge them and them split them by commas, so we end up with only
        // the selectors
        var s = aRules.join(' ');
        // Remove selectors splitting the elements, leave only the class selector (.)
        s = s.replace( /(,|>|\+|~)/g, ' ' );
        // Remove attribute selectors: table[border="0"]
        s = s.replace( /\[[^\]]*/g, '' );
        // Remove Ids: div#main
        s = s.replace( /#[^\s]*/g, '' );
        // Remove pseudo-selectors and pseudo-elements: :hover :nth-child(2n+1) ::before
        s = s.replace( /\:{1,2}[^\s]*/g, '' );

        s = s.replace( /\s+/g, ' ' );

        var aSelectors = s.split( ' ' ),
            aClasses = [];

        for ( var i = 0; i < aSelectors.length ; i++ )
        {
            var selector = aSelectors[ i ];

            if ( validSelectors.test( selector ) && !skipSelectors.test( selector ) )
            {
                // If we still don't know about this one, add it
                if ( CKEDITOR.tools.indexOf( aClasses, selector ) == -1 )
                    aClasses.push( selector );
            }
        }

        return aClasses;
    }

    function LoadStylesCSS( theDoc, skipSelectors, validSelectors )
    {
        var styles = [],
            // It will hold all the rules of the applied stylesheets (except those internal to CKEditor)
            aRules = [],
            i;

        for ( i = 0; i < theDoc.styleSheets.length; i++ )
        {
            var sheet = theDoc.styleSheets[ i ],
                node = sheet.ownerNode || sheet.owningElement;

            // Skip the internal stylesheets
            if ( node.getAttribute( 'data-cke-temp' ) )
                continue;

            // Exclude stylesheets injected by extensions
            if ( sheet.href && sheet.href.substr(0, 9) == 'chrome://' )
                continue;

            var sheetRules = sheet.cssRules || sheet.rules;
            for ( var j = 0; j < sheetRules.length; j++ )
                aRules.push( sheetRules[ j ].selectorText );
        }

        var aClasses = parseClasses( aRules, skipSelectors, validSelectors );

        // Add each style to our "Styles" collection.
        for ( i = 0; i < aClasses.length; i++ )
        {
            var oElement = aClasses[ i ].split( '.' ),
                element = oElement[ 0 ].toLowerCase(),
                sClassName = oElement[ 1 ];

            styles.push( {
                name : element + '.' + sClassName,
                element : element,
                attributes : {'class' : sClassName}
            });
        }

        return styles;
    }

    // Register a plugin named "stylesheetparser".
    CKEDITOR.plugins.add( 'stylesheetparser',
    {
        requires: [ 'styles' ],
        onLoad : function()
        {
            var obj = CKEDITOR.editor.prototype;
            obj.getStylesSet = CKEDITOR.tools.override( obj.getStylesSet,  function( org )
            {
                return function( callback )
                {
                    var self = this;
                    org.call( this, function( definitions )
                    {
                        // Rules that must be skipped
                        var skipSelectors = self.config.stylesheetParser_skipSelectors || ( /(^body\.|^\.)/i ),
                            // Rules that are valid
                            validSelectors = self.config.stylesheetParser_validSelectors || ( /\w+\.\w+/ );

                        callback( ( self._.stylesDefinitions = definitions.concat( LoadStylesCSS( self.document.$, skipSelectors, validSelectors ) ) ) );
                    });
                };
            });

        }
    });
})();


/**
 * A regular expression that defines whether a CSS rule will be
 * skipped by the Stylesheet Parser plugin. A CSS rule matching
 * the regular expression will be ignored and will not be available
 * in the Styles drop-down list.
 * @name CKEDITOR.config.stylesheetParser_skipSelectors
 * @type RegExp
 * @default /(^body\.|^\.)/i
 * @since 3.6
 * @see CKEDITOR.config.stylesheetParser_validSelectors
 * @example
 * // Ignore rules for body and caption elements, classes starting with "high", and any class defined for no specific element.
 * config.stylesheetParser_skipSelectors = /(^body\.|^caption\.|\.high|^\.)/i;
 */

 /**
 * A regular expression that defines which CSS rules will be used
 * by the Stylesheet Parser plugin. A CSS rule matching the regular
 * expression will be available in the Styles drop-down list.
 * @name CKEDITOR.config.stylesheetParser_validSelectors
 * @type RegExp
 * @default /\w+\.\w+/
 * @since 3.6
 * @see CKEDITOR.config.stylesheetParser_skipSelectors
 * @example
 * // Only add rules for p and span elements.
 * config.stylesheetParser_validSelectors = /\^(p|span)\.\w+/;
 */