var Calendar = {
        /*
        * parses the date string in the format yyyy-mm-dd
        * can be overloaded to support other date string formats
        *
        * returns the date object
        */
    parse : function( dateString) {
        datePattern = /(\d\d\d\d)-(\d\d)-(\d\d)/;
        if ( result=dateString.match( datePattern)) 
        { 
            date = new Date();
            date.setFullYear( result[1], result[2]-1, result[3]);
            return date;
        }
        else
        {
            return "Orangevolt Calendar : Parsing date '" + dateString + "' using pattern '" + datePattern + "' failed.";
        }
    },
    
        /*
        * returns the html replacing the blogger date
        */
    renderHTML : function( date, origDateString) {
        months = [ 'Jan', 'Feb', 'Mar', 'Apr', 'Maj', 'Jun', 'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dec'];
        
        return "<span class='cal' title='" + 
            origDateString + 
            "'><span class='cal_month'>" + 
            months[ date.getMonth()] + 
            "</span><span class='cal_day'>" + 
            date.getDate() + 
            "</span></span>";
    },
    
    inject : function() {
        $$('h2.date-header').each( function( date_header) {
            text = date_header.lastChild.nodeValue;
            date = Calendar.parse( text);         
            if( 'object'== typeof date)  // date object was returned (i.e. as expected)
            {
                    date_header.lastChild.nodeValue="";
                    new Insertion.Bottom( 
                        date_header,
                        Calendar.renderHTML( date, text)
                    )
            }
            else                            // not-a-date-object-but-something-else was returned -> error
            {
                new Insertion.Bottom(
                    date_header,
                    "<span style='color:red;font-style:italic'>" + date + "</span>"
                );
            }
        });
    },

    Calendar : function() {
        /*
        * make calendar widget unobtrusive
        * and call it after the dom tree is completely loaded
        */
        //Event.observe( window, 'load', Calendar.inject, false);
        FastInit.addOnLoad( Calendar.inject);
    }
};

Calendar.Calendar();