var DatePicker= function(){
	
	var datePickerDivID = "datepicker";
	var iFrameDivID = "datepickeriframe";
	var divno=1;

	var dayArrayShort = { 
		en: ['Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa','Su'],
		de: ['Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa','So']
	};
	var dayArrayMed = {
		en: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat','Sun'],
		de: ['Mon', 'Die', 'Mit', 'Don', 'Fre', 'Sam', 'Son']
	};
	var dayArrayLong = {
		en: ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday','Sunday'],
		de: ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday','Sunday']
	};
	var monthArrayShort = {
		en: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'],
		de: ['Jan', 'Feb', 'Mär', 'Apr', 'Mai', 'Jun', 'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dez']
	};
	var monthArrayMed = {
		en: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'June', 'July', 'Aug', 'Sept', 'Oct', 'Nov', 'Dec'],
		de: ['Jan', 'Feb', 'Mär', 'Apr', 'Mai', 'Jun', 'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dez']
	};
	var monthArrayLong = {
		en: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'],
		de: ['Januar', 'Februar', 'März', 'April', 'Mai', 'Juni', 'Juli', 'August', 'September', 'Oktober', 'November', 'Dezember']
	};
	
	var buttonText= {
		en: 'select',
		de: 'wählen'
	};
	
	var headline= {
		en: 'Date of Arrival',
		de: 'Anreisedatum'
	};
	
	var buttons={
		en: {
			close: 'close',
			thismonth: 'this month'
		},
		de: {
			close: 'schließen',
			thismonth: 'akt. Monat'
		}
	};
	// these variables define the date formatting we're expecting and outputting.
	// If you want to use a different format by default, change the defaultDateSeparator
	// and defaultDateFormat variables either here or on your HTML page.
	var defaultDateSeparator = "/";        // common values would be "/" or "."
	var defaultDateFormat = "dmy";    // valid values are "mdy", "dmy", and "ymd"
	var dateSeparator = defaultDateSeparator;
	var dateFormat = defaultDateFormat;
	var language='de';


	return {
		
		varPrefix: 'tx_shfrtkn',
		
		constructDatePicker: function(id,date,lang,head,varPrefix) {
			var el=$(id);
			
			if (!lang) lang='de';
			this.varPrefix=varPrefix || 'tx_shfrtkn';
			language=lang;
			//head = (typeof head=="undefined") ? headline[lang]+'<br />' : ((head) ? head+'<br />' : '');
			
			if (el) {
				var pickButton=document.createElement('IMG');
				pickButton.src="typo3conf/ext/shfr_tkn/res/calendar.png";
				pickButton.className='dpSelectButton';
				pickButton.formId=id;
				pickButton.lang=lang;
				pickButton.onclick=function() {
					DatePicker.displayDatePicker(this.formId, el, 'dmy', '.',this.lang);
				};
				var lastTD=$A(el.getElementsByTagName('td')).pop();
				var myTD=document.createElement('TD');
				myTD.className='pickerCell';
				myTD.appendChild(pickButton);
				lastTD.parentNode.appendChild(myTD);
				
			};
		},
		
		displayDatePicker: function(formId, displayBelowThisObject, dtFormat, dtSep, lang) {
		  this.formId=formId;
 
		  // if a date separator character was given, update the dateSeparator variable
		  if (dtSep)
		    dateSeparator = dtSep;
		  else
		    dateSeparator = defaultDateSeparator;
 
		  // if a date format was given, update the dateFormat variable
		  if (dtFormat)
		    dateFormat = dtFormat;
		  else
		    dateFormat = defaultDateFormat;
		
		  if (lang) language=lang;
		
		  var x = displayBelowThisObject.offsetLeft;
		  var y = displayBelowThisObject.offsetTop + displayBelowThisObject.offsetHeight ;
 
		  // deal with elements inside tables and such
		  var parent = displayBelowThisObject;
		  while (parent.offsetParent) {
		    parent = parent.offsetParent;
		    x += parent.offsetLeft;
		    y += parent.offsetTop ;
		  }
 
		  this.drawDatePicker(x, y);
		},

		/**
		Draw the datepicker object (which is just a table with calendar elements) at the
		specified x and y coordinates, using the targetDateField object as the input tag
		that will ultimately be populated with a date.

		This function will normally be called by the displayDatePicker function.*/
		drawDatePicker: function(x, y) {
		  var dt = this.getFieldDate();
		
 
		  // the datepicker table will be drawn inside of a <div> with an ID defined by the
		  // global datePickerDivID variable. If such a div doesn't yet exist on the HTML
		  // document we're working with, add one.
		  if (!document.getElementById(datePickerDivID)) {
		    // don't use innerHTML to update the body, because it can cause global variables
		    // that are currently pointing to objects on the page to have bad references
		    //document.body.innerHTML += "<div id='" + datePickerDivID + "' class='dpDiv'></div>";
		    var newNode = document.createElement("div");
		    newNode.setAttribute("id", datePickerDivID);
		    newNode.setAttribute("class", "dpDiv");
		    newNode.setAttribute("style", "visibility: hidden;");
		    document.body.appendChild(newNode);
		  }
 
		  // move the datepicker div to the proper x,y coordinate and toggle the visiblity
		  var pickerDiv = document.getElementById(datePickerDivID);
		  pickerDiv.style.position = "absolute";
		  pickerDiv.style.left = x + "px";
		  pickerDiv.style.top = y + "px";
		  pickerDiv.style.visibility = (pickerDiv.style.visibility == "visible" ? "hidden" : "visible");
		  pickerDiv.style.display = (pickerDiv.style.display == "block" ? "none" : "block");
		  pickerDiv.style.zIndex = 10000;
 
		  // draw the datepicker table
		  this.refreshDatePicker(dt.getFullYear(), dt.getMonth(), dt.getDate());
		},
		/**
		This is the function that actually draws the datepicker calendar.*/
		refreshDatePicker: function(year, month, day) {
		  // if no arguments are passed, use today's date; otherwise, month and year
		  // are required (if a day is passed, it will be highlighted later)
		  var thisDay = new Date();
 
		  if ((month >= 0) && (year > 0)) {
		    thisDay = new Date(year, month, 1);
		  } else {
		    day = thisDay.getDate();
		    thisDay.setDate(1);
		  }
 
		  // the calendar will be drawn as a table
		  // you can customize the table elements with a global CSS style sheet,
		  // or by hardcoding style and formatting elements below
		  var crlf = "\n";
		  var TABLE = "<table cols=7 class='dpTable'>" + crlf;
		  var xTABLE = "</table>" + crlf;
		  var TR = "<tr class='dpTR'>";
		  var TR_title = "<tr class='dpTitleTR'>";
		  var TR_days = "<tr class='dpDayTR'>";
		  var TR_todaybutton = "<tr class='dpTodayButtonTR'>";
		  var xTR = "</tr>" + crlf;
		  var TD = "<td class='dpTD' onMouseOut='this.className=\"dpTD\";' onMouseOver=' this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
		  var TD_title = "<td colspan=5 class='dpTitleTD'>";
		  var TD_buttons = "<td class='dpButtonTD'>";
		  var TD_todaybutton = "<td colspan=7 class='dpTodayButtonTD'>";
		  var TD_days = "<td class='dpDayTD'>";
		  var TD_selected = "<td class='dpDayHighlightTD' onMouseOut='this.className=\"dpDayHighlightTD\";' onMouseOver='this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
		  var xTD = "</td>" + crlf;
		  var DIV_title = "<div class='dpTitleText'>";
		  var DIV_selected = "<div class='dpDayHighlight'>";
		  var xDIV = "</div>";
 
		  // start generating the code for the calendar table
		  var html = TABLE;
 
		  // this is the title bar, which displays the month and the buttons to
		  // go back to a previous month or forward to the next month
		  html += TR_title;
			html+='<td colspan="7"><table width="100%"><tr>';
		  html += TD_buttons + this.getButtonCode(thisDay, -1, "&lt;") + xTD;
		  html += TD_title + DIV_title + monthArrayLong[language][ thisDay.getMonth()] + " " + thisDay.getFullYear() + xDIV + xTD;
		  html += TD_buttons + this.getButtonCode(thisDay, 1, "&gt;") + xTD;
			html+='</tr></table></td>';
		  html += xTR;
 
		  // this is the row that indicates which day of the week we're on
		  html += TR_days;
		  for(i = 0; i < dayArrayShort[language].length; i++)
		    html += TD_days + dayArrayShort[language][i] + xTD;
		  html += xTR;
 
		  // now we'll start populating the table with days of the month
		  html += TR;
 
		  // first, the leading blanks
		  for (i = 0; i < (thisDay.getDay()+6)%7; i++)
		    html += TD + "&nbsp;" + xTD;
 
		  // now, the days of the month
		  do {
		    dayNum = thisDay.getDate();
		    var TD_onclick = " onclick=\"DatePicker.updateDateField("+thisDay.getTime() + ");\">";
    
		    if (dayNum == day)
		      html += TD_selected + TD_onclick + DIV_selected + dayNum + xDIV + xTD;
		    else
		      html += TD + TD_onclick + dayNum + xTD;
    
		    // if this is a Saturday, start a new row
		    if (thisDay.getDay() == 0)
		      html += xTR + TR;
    
		    // increment the day
		    thisDay.setDate(thisDay.getDate() + 1);
		  } while (thisDay.getDate() > 1)
 
		  // fill in any trailing blanks
		  if (thisDay.getDay() > 0) {
		    for (i = 6; i > thisDay.getDay(); i--)
		      html += TD + "&nbsp;" + xTD;
		  }
		  html += xTR;
 
		  // add a button to allow the user to easily return to today, or close the calendar
		  var today = new Date();
		  var todayString = "Today is " + dayArrayMed[language][today.getDay()] + ", " + monthArrayMed[language][ today.getMonth()] + " " + today.getDate();
		  html += TR_todaybutton + TD_todaybutton;
		  html += "<button class='dpTodayButton' onClick='DatePicker.refreshDatePicker();'>"+buttons[language].thismonth+"</button> ";
		  html += "<button class='dpTodayButton' onClick='DatePicker.updateDateField();'>"+buttons[language].close+"</button>";
		  html += xTD + xTR;
 
		  // and finally, close the table
		  html += xTABLE;
 
		  document.getElementById(datePickerDivID).innerHTML = html;
		  // add an "iFrame shim" to allow the datepicker to display above selection lists
		  this.adjustiFrame();
		},

		/**
		Convenience function for writing the code for the buttons that bring us back or forward
		a month.*/
		getButtonCode: function(dateVal, adjust, label) {
		  var newMonth = (dateVal.getMonth () + adjust) % 12;
		  var newYear = dateVal.getFullYear() + parseInt((dateVal.getMonth() + adjust) / 12,10);
		  if (newMonth < 0) {
		    newMonth += 12;
		    newYear += -1;
		  };
 
		  return "<button class='dpButton' onClick='DatePicker.refreshDatePicker("+newYear + ", " + newMonth + ");'>" + label + "</button>";
		},

		/**
		Convert a string to a JavaScript Date object.*/
		getFieldDate: function() {
			
		  try {
			var d=document.getElementsByName(this.varPrefix+'['+this.formId+'][day]').item(0).value;
			var m=document.getElementsByName(this.varPrefix+'['+this.formId+'][month]').item(0).value-1;
			var y=document.getElementsByName(this.varPrefix+'['+this.formId+'][year]').item(0).value;
		
		    dateVal = new Date(y, m, d);
		  } catch(e) {
			console.log(e);
		    dateVal = new Date();
		  }
 
		  return dateVal;
		},
		updateDateField: function(timestamp) {
			
			var a=new Date();
			a.setTime(timestamp);
			
			document.getElementsByName(this.varPrefix+'['+this.formId+'][day]').item(0).value=a.getDate();
			document.getElementsByName(this.varPrefix+'['+this.formId+'][month]').item(0).value=a.getMonth()+1;
			document.getElementsByName(this.varPrefix+'['+this.formId+'][year]').item(0).value=a.getFullYear();
 
		  var pickerDiv = document.getElementById(datePickerDivID);
		  pickerDiv.style.visibility = "hidden";
		  pickerDiv.style.display = "none";
 
		  this.adjustiFrame();
		  
		},
		/**
		Use an "iFrame shim" to deal with problems where the datepicker shows up behind
		selection list elements, if they're below the datepicker. The problem and solution are
		described at:

		http://dotnetjunkies.com/WebLog/jking/archive/2003/07/21/488.aspx
		http://dotnetjunkies.com/WebLog/jking/archive/2003/10/30/2975.aspx*/
		adjustiFrame: function(pickerDiv, iFrameDiv) {
		  // we know that Opera doesn't like something about this, so if we
		  // think we're using Opera, don't even try
		  var is_opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1);
		  if (is_opera)
		    return;
  
		  // put a try/catch block around the whole thing, just in case
		  try {
		    if (!document.getElementById(iFrameDivID)) {
		      // don't use innerHTML to update the body, because it can cause global variables
		      // that are currently pointing to objects on the page to have bad references
		      //document.body.innerHTML += "<iframe id='" + iFrameDivID + "' src='javascript:false;' scrolling='no' frameborder='0'>";
		      var newNode = document.createElement("iFrame");
		      newNode.setAttribute("id", iFrameDivID);
		      newNode.setAttribute("src", "javascript:false;");
		      newNode.setAttribute("scrolling", "no");
		      newNode.setAttribute ("frameborder", "0");
		      document.body.appendChild(newNode);
		    }
    
		    if (!pickerDiv)
		      pickerDiv = document.getElementById(datePickerDivID);
		    if (!iFrameDiv)
		      iFrameDiv = document.getElementById(iFrameDivID);
    
		    try {
		      iFrameDiv.style.position = "absolute";
		      iFrameDiv.style.width = pickerDiv.offsetWidth;
		      iFrameDiv.style.height = pickerDiv.offsetHeight ;
		      iFrameDiv.style.top = pickerDiv.style.top;
		      iFrameDiv.style.left = pickerDiv.style.left;
		      iFrameDiv.style.zIndex = pickerDiv.style.zIndex - 1;
		      iFrameDiv.style.visibility = pickerDiv.style.visibility ;
		      iFrameDiv.style.display = pickerDiv.style.display;
		    } catch(e) {
				console.log(e);
		    }
 
		  } catch (ee) {
			console.log(ee);
		  }
 
		}
	}
}();