/**********************************************************************
*          Calendar JavaScript [DOM] v3.09 by Michael Loesler          *
************************************************************************
* Copyright (C) 2005-08 by Michael Loesler, http//derletztekick.com    *
*                                                                      *
*                                                                      *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 3 of the License, or    *
* (at your option) any later version.                                  *
*                                                                      *
* This program is distributed in the hope that it will be useful,      *
* but WITHOUT ANY WARRANTY; without even the implied warranty of       *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
* GNU General Public License for more details.                         *
*                                                                      *
* You should have received a copy of the GNU General Public License    *
* along with this program; if not, see <http://www.gnu.org/licenses/>  *
* or write to the                                                      *
* Free Software Foundation, Inc.,                                      *
* 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.            *
*                                                                      *
 **********************************************************************/

/**
 *
 * @access public
 * @return void
 **/
function closeReturn(date, id) {
    $(id).hide();
    return date;

}


function CalendarJS() {
    this.id = null;
    this.input = null;
    /**
     * Aktuelles Datum
     */
    this.now = new Date();

    /**
     * Namen der Tage
     */
    this.dayname = ["Mo","Di","Mi","Do","Fr","Sa","So"];

    /**
     * Namen der Monate
     */
    this.monthname = ["Januar","Februar","März","April","Mai","Juni","Juli","August","September","Oktober","November","Dezember"];

    /**
     * Texte für Tooltips
     */
    this.tooltip = ["vorheriger Monat","nächster Monat","aktuelles Datum"];
    this.monthCell = document.createElement("th");
    this.tableHead = null;
    this.parEl = null;

    /**
     * init
     */
    this.init = function(id, input) {
        this.id = id;
        this.input = input;
        this.date = this.now.getDate();
        this.month = this.mm = this.now.getMonth();
        this.year = this.yy = this.now.getFullYear();
        this.monthCell.colSpan = 5;
        this.monthCell.appendChild(document.createTextNode( this.monthname[this.mm]+" "+this.yy ));
        this.tableHead = this.createTableHead();
        this.parEl = document.getElementById(id);
        this.show();
        this.checkDate();
    },

    /**
     * checkDate
     */
    this.checkDate = function() {
        var self = this;
        var today = new Date();
        if (this.date != today.getDate()) {
        this.date  = today.getDate();
        if (this.mm == this.month && this.yy == this.year)
        	this.switchMonth("current");
        this.month = today.getMonth();
        if (this.mm == this.month && this.yy == this.year)
        	this.switchMonth("current");
        this.year  = today.getFullYear();
        if (this.mm == this.month && this.yy == this.year)
        	this.switchMonth("current");
        }
        window.setTimeout(function() { self.checkDate(); }, Math.abs(new Date(this.year, this.month, this.date, 24, 0, 0)-this.now));
    },

    /**
     * removeElements
     */
    this.removeElements = function( Obj ) {
        for (var i=0; i<Obj.childNodes.length; i++) {
            Obj.removeChild(Obj.childNodes[i]);
        }
        return Obj;
    },

    /**
     * show
     */
    this.show = function() {
        this.parEl = this.removeElements( this.parEl );
        this.monthCell.firstChild.replaceData(0, this.monthCell.firstChild.nodeValue.length, this.monthname[this.mm]+" "+this.yy);
        var table = document.createElement("table");
        table.appendChild( this.createTableBody() );
        table.appendChild( this.tableHead );
        this.parEl.appendChild( table );
    },

    /**
     * createTableHead
     */
    this.createTableHead = function() {
        var thead = document.createElement("thead");
        var tr = document.createElement("tr");
        var th = this.getCell( "th", "\u00AB", "last_month" )
        th.Instanz = this;
        th.onclick = function() { this.Instanz.switchMonth("prev"); };
        th.title = this.tooltip[0];
        try { th.style.cursor = "pointer"; } catch(e){ th.style.cursor = "hand"; }
        tr.appendChild( th );
        this.monthCell.Instanz = this;
        this.monthCell.onclick = function() { this.Instanz.switchMonth("current"); };
        this.monthCell.title = this.tooltip[2];
        try { this.monthCell.style.cursor = "pointer"; } catch(e){ this.monthCell.style.cursor = "hand"; }
        tr.appendChild( this.monthCell );
        th = this.getCell( "th", "\u00BB", "next_month" )
        th.Instanz = this;
        th.onclick = function() { this.Instanz.switchMonth("next"); };
        th.title = this.tooltip[1];
        try { th.style.cursor = "pointer"; } catch(e){ th.style.cursor = "hand"; }
        tr.appendChild( th );
        thead.appendChild( tr );
        tr = document.createElement('tr');
        for (var i=0; i<this.dayname.length; i++)
        tr.appendChild( this.getCell("th", this.dayname[i], "weekday" ) );
        thead.appendChild( tr );
        return thead;
    },

		this.createTableBody = function() {
			var dayspermonth = [31,28,31,30,31,30,31,31,30,31,30,31];
			var sevendaysaweek = 0;
			var begin = new Date(this.yy, this.mm, 1);
			var firstday = begin.getDay()-1;
			if (firstday < 0)
				firstday = 6;
			if ((this.yy%4==0) && ((this.yy%100!=0) || (this.yy%400==0)))
				dayspermonth[1] = 29;
			var tbody = document.createElement("tbody");
			var tr = document.createElement('tr');
			if (firstday == 0) {
				for (var i=0; i<this.dayname.length; i++) {
					var prevMonth = (this.mm == 0)?11:this.mm-1;
					tr.appendChild( this.getCell( "td", dayspermonth[prevMonth]-6+i, "last_month" ) );
				}
				tbody.appendChild( tr );
				tr = document.createElement('tr');
			}

			for (var i=0; i<firstday; i++, sevendaysaweek++) {
				var prevMonth = (this.mm == 0)?11:this.mm-1;
				tr.appendChild( this.getCell( "td", dayspermonth[prevMonth]-firstday+i+1, "last_month" ) );

			}

			for (var i=1; i<=dayspermonth[this.mm]; i++, sevendaysaweek++){
				if (this.dayname.length == sevendaysaweek){
					tbody.appendChild( tr );
					tr = document.createElement('tr');
					sevendaysaweek = 0;
				}
				if (i==this.date && this.mm==this.month && this.yy==this.year && (sevendaysaweek == 5 || sevendaysaweek == 6))
					tr.appendChild( this.getCell( "td", i, "today weekend" ) );
				else if (i==this.date && this.mm==this.month && this.yy==this.year)
					tr.appendChild( this.getCell( "td", i, "today" ) );
				else if (sevendaysaweek == 5)
					tr.appendChild( this.getCell( "td", i, "saturday weekend" ) );
				else if (sevendaysaweek == 6)
					tr.appendChild( this.getCell( "td", i, "sunday weekend" ) );
				else
					tr.appendChild( this.getCell( "td", i, null ) );
			}

			var daysNextMonth = 1;
			for (var i=sevendaysaweek; i<this.dayname.length; i++)
				tr.appendChild( this.getCell( "td", daysNextMonth++, "next_month"  ) );

			tbody.appendChild( tr );

			while (tbody.getElementsByTagName("tr").length<6) {
				tr = document.createElement('tr');
				for (var i=0; i<this.dayname.length; i++)
					tr.appendChild( this.getCell( "td", daysNextMonth++, "next_month"  ) );
				tbody.appendChild( tr );
			}
			return tbody;

		},

		this.getCell = function(tag, str, cssClass) {
			var El = document.createElement( tag );
            if (typeof(str) == "number") {
                // Tag mit führender Null
                if (str < 10) {
                    str = "0" + str;
                }
                // Monat mir führender Null
                var month = (this.mm + 1);
                if (month<10) {
                    month = "0" + month;
                }
                var dateLastPart = "." + month + "." + this.yy;
                var id = this.id;
                var input = this.input;
                El.onclick = function() {
                    $(id).hide();

                    input.value=str + dateLastPart, id;
                };
                var Link = document.createElement('a');
                Link.appendChild(document.createTextNode( str ));
    			El.appendChild(Link);
           } else {
                El.appendChild(document.createTextNode( str ));
           }

			if (cssClass != null)
				El.className = cssClass;
			return El;
		},

		this.switchMonth = function( s ){
			switch (s) {
				case "prev":
					this.yy = (this.mm == 0)?this.yy-1:this.yy;
					this.mm = (this.mm == 0)?11:this.mm-1;
				break;

				case "next":
					this.yy = (this.mm == 11)?this.yy+1:this.yy;
					this.mm = (this.mm == 11)?0:this.mm+1;
				break;

				case "current":
					this.yy = this.year;
					this.mm = this.month;
				break;
			}
			this.show();
		}
	}

    /**
     *
     * @access public
     * @return void
     **/
    function showCalendar(element, id) {
        //Element.extend(element);
        var date = new CalendarJS().init(id, element);
        $(id).show();
        return date;
    }

    function hideCalendar(id) {
        $("calendar").hide();
        $("calendar2").hide();
    }

    addOnload(hideCalendar);