/*
'Author					: Stefan Kruger
'Date Created			: 18-Apr-2005
'Last Changed by		: Stefan Kruger
'Date Changed			: 18-Apr-2005
'Version				: 1.0.18042005
'Comments:
'Date:			Desc:															
'--------------------------------------------------------------------------------------------

'ToDoList:
'Date:		Desc:															Status:
'--------------------------------------------------------------------------------------------
*/

//Static declarations
var now = new Date();
var firstyear = now.getFullYear() - 100;		//Number of years back to display.
var lastyear = (now.getFullYear() + 1) + 10 ;	//Number of years forward to display.
var colour = "#BEBEBE";						//Text color of greyed out days.
var coltoday = "#D61010";					//Text color of today.

//Set up todays date
var day = now.getDate();
var month = now.getMonth();
var year = now.getFullYear();
//Not needed yet --> 'if (year < 2000) year = year + 1900;'

//Set up calendar display vars
var daycell = new Array();
var cellday = new Array();
var n;

//Draw calendar function (param = div tag object to display it in)
function calendar(div,gridmode){
	calobj = "";
	if (gridmode) {
		calobj += '<form name="' + cal_formname + '">';
	}
	var calobj
	calobj+='<table border="0" cellspacing="0" cellpadding="0">'
	calobj+='<tr><td>'
	calobj+='<table border="0" cellspacing="2" cellpadding="0" class="calender">'
	calobj+='<tr><td>'
	calobj+='<select name="calmonth_' + div.id + '" onChange="updatecalendar()" class="caldropdowns">'
	calobj+='<option>January</option><option>February</option><option>March</option>'
	calobj+='<option>April</option><option>May</option><option>June</option>'
	calobj+='<option>July</option><option>August</option><option>September</option>'
	calobj+='<option>October</option><option>November</option><option>December</option>'
	calobj+='</select></td>'
	calobj+='<td align="right">'
	calobj+='<select name="calyear_' + div.id + '" onChange="updatecalendar()" class="caldropdowns">'
	for (n=firstyear;n<lastyear;n++){
		if (n==year){
			calobj+='<option selected value="'+n+'">'+n+'</option>'
		}
		else {
			calobj+='<option value="'+n+'">'+n+'</option>'
		}
	}
	calobj+='</select>'
	calobj+='</td></tr>'
	
	calobj+='<tr><td colspan="2" class="calinsideborder">'
	calobj+='<table cellspacing="1" class="calinsidesettings" border="0">'
	calobj+='<tr align="center">'
	calobj+='<td width="29" height="15" class="caldays">Sun</td>'
	calobj+='<td width="29" height="15" class="caldays">Mon</td>'
	calobj+='<td width="29" height="15" class="caldays">Tue</td>'
	calobj+='<td width="29" height="15" class="caldays">Wed</td>'
	calobj+='<td width="29" height="15" class="caldays">Thu</td>'
	calobj+='<td width="29" height="15" class="caldays">Fri</td>'
	calobj+='<td width="29" height="15" class="caldays">Sat</td>'
	calobj+='</tr>'
	var calcell,calrow
	for (calcell=0;calcell<6;calcell++){
		calobj+='<tr>'
		calobj+='<td width="29" height="15" class="calwknd" id="cal'+(calcell*7)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwkdy" id="cal'+(calcell*7+1)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+1)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwkdy" id="cal'+(calcell*7+2)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+2)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwkdy" id="cal'+(calcell*7+3)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+3)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwkdy" id="cal'+(calcell*7+4)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+4)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwkdy" id="cal'+(calcell*7+5)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+5)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='<td width="29" height="15" class="calwknd" id="cal'+(calcell*7+6)+'_' + thecaldiv.id + '" onclick=message('+(calcell*7+6)+',thecaldiv,'+gridmode+');>&nbsp;</td>'
		calobj+='</tr>'
	}
	calobj+='</table>'
	calobj+='</td></tr>'
	
	calobj+='<tr>'
	calobj+='<td align="center" colspan="2">'
	calobj+='<table cellpadding="0" cellspacing="0" border="0">'
	calobj+='<tr>'
	
	calobj+='<td width=18>'
	calobj+='<input type="button" name="backyear" value="&lt;&lt;" class="calbutts" onclick=gobackyear();updatecalendar()>'
	calobj+='</td>'
	calobj+='<td width=24 align=right>'
	calobj+='<input type="button" name="backmonth" value="&lt;" class="calbutts" onclick=gobackmonth();updatecalendar()>'
	calobj+='</td>'
	calobj+='<td width=80 align=center>'
	calobj+='<input type="button" name="TODAY" value="TODAY" class="calbutts" onclick=caltoday()>'
	calobj+='</td>'
	calobj+='<td width=24 align=left>'
	calobj+='<input type="button" name="onmonth" value="&gt;" class="calbutts" onclick=goonmonth();updatecalendar()>'
	calobj+='</td>'
	calobj+='<td width=18>'
	calobj+='<input type="button" name="onyear" value="&gt;&gt;" class="calbutts" onclick=goonyear();updatecalendar()>'
	calobj+='</td>'
	calobj+='</tr></table>'
	calobj+='</td></tr>'
	calobj+='</table></td>'
	calobj+='<td width=2 class=shadow valign=top>'
	calobj+='<table cellpadding="0" cellspacing="0" border="0">'
	calobj+='<tr>'
	calobj+='<td height=3 width=2>'
	

	calobj+='<table cellpadding="0" cellspacing="0" border="0"><tr><td height=1 width=1 class=white></td><td height=1 width=1 class=white></td></tr>'
	calobj+='<tr><td height=1 width=1></td><td height=1 width=1 class=white></td></tr></table>'
								
	calobj+='</td>'
	calobj+='</tr></table>'
	calobj+='</td>'
	calobj+='</tr>'
	calobj+='<tr>'
	calobj+='<td height=2 colspan="2" class=shadow align=left>'
	calobj+='<table cellpadding="0" cellspacing="0" border="0">'
	calobj+='<tr>'
	calobj+='<td width=3>'
	
	calobj+='<table cellpadding="0" cellspacing="0" border="0"><tr><td height=1 width=1 class=white></td><td height=1 width=1></td></tr><tr><td height=1 width=1 class=white></td><td height=1 width=1 class=white></td></tr></table>'
	
	calobj+='</td>'
	calobj+='</tr></table>'
	calobj+='</td></tr>'
	calobj+='</table>'
	
	if (gridmode) {
		calobj += '</form>';
	}
	/////////////////////////////////////////////////////////////////////
	//Writes the calender to div tag object
	div.innerHTML = calobj;
	/////////////////////////////////////////////////////////////////////

	//Assign cells of calendar days to an array
	/*Changed from eval --> document.getElementById*/
	daycell[0]=document.getElementById('cal0_' + thecaldiv.id);
	daycell[1]=document.getElementById('cal1_' + thecaldiv.id);
	daycell[2]=document.getElementById('cal2_' + thecaldiv.id);
	daycell[3]=document.getElementById('cal3_' + thecaldiv.id);
	daycell[4]=document.getElementById('cal4_' + thecaldiv.id);
	daycell[5]=document.getElementById('cal5_' + thecaldiv.id);
	daycell[6]=document.getElementById('cal6_' + thecaldiv.id);
	daycell[7]=document.getElementById('cal7_' + thecaldiv.id);
	daycell[8]=document.getElementById('cal8_' + thecaldiv.id);
	daycell[9]=document.getElementById('cal9_' + thecaldiv.id);
	daycell[10]=document.getElementById('cal10_' + thecaldiv.id);
	daycell[11]=document.getElementById('cal11_' + thecaldiv.id);
	daycell[12]=document.getElementById('cal12_' + thecaldiv.id);
	daycell[13]=document.getElementById('cal13_' + thecaldiv.id);
	daycell[14]=document.getElementById('cal14_' + thecaldiv.id);
	daycell[15]=document.getElementById('cal15_' + thecaldiv.id);
	daycell[16]=document.getElementById('cal16_' + thecaldiv.id);
	daycell[17]=document.getElementById('cal17_' + thecaldiv.id);
	daycell[18]=document.getElementById('cal18_' + thecaldiv.id);
	daycell[19]=document.getElementById('cal19_' + thecaldiv.id);
	daycell[20]=document.getElementById('cal20_' + thecaldiv.id);
	daycell[21]=document.getElementById('cal21_' + thecaldiv.id);
	daycell[22]=document.getElementById('cal22_' + thecaldiv.id);
	daycell[23]=document.getElementById('cal23_' + thecaldiv.id);
	daycell[24]=document.getElementById('cal24_' + thecaldiv.id);
	daycell[25]=document.getElementById('cal25_' + thecaldiv.id);
	daycell[26]=document.getElementById('cal26_' + thecaldiv.id);
	daycell[27]=document.getElementById('cal27_' + thecaldiv.id);
	daycell[28]=document.getElementById('cal28_' + thecaldiv.id);
	daycell[29]=document.getElementById('cal29_' + thecaldiv.id);
	daycell[30]=document.getElementById('cal30_' + thecaldiv.id);
	daycell[31]=document.getElementById('cal31_' + thecaldiv.id);
	daycell[32]=document.getElementById('cal32_' + thecaldiv.id);
	daycell[33]=document.getElementById('cal33_' + thecaldiv.id);
	daycell[34]=document.getElementById('cal34_' + thecaldiv.id);
	daycell[35]=document.getElementById('cal35_' + thecaldiv.id);
	daycell[36]=document.getElementById('cal36_' + thecaldiv.id);
	daycell[37]=document.getElementById('cal37_' + thecaldiv.id);
	daycell[38]=document.getElementById('cal38_' + thecaldiv.id);
	daycell[39]=document.getElementById('cal39_' + thecaldiv.id);
	daycell[40]=document.getElementById('cal40_' + thecaldiv.id);
	daycell[41]=document.getElementById('cal41_' + thecaldiv.id);

	caltoday()
}

//Set today function
function caltoday(){
	day = now.getDate();
	eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex=now.getMonth();
	eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value=now.getFullYear();
	updatecalendar()
}

//Refresh calendar display function
function updatecalendar(){
	month = eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex
	year  = eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value

	var firstOfMonth = new Date (year, month, 1);
	var startingPos = firstOfMonth.getDay();
	var curday=1
	var days=monthdays(month,year)
	var prevdays=monthdays(month-1,year)
	var str
	for (n=0; n<42; n++){
		if (startingPos==n){
			if (month==now.getMonth()&year==now.getFullYear()&curday==now.getDate()){
				str=curday
				daycell[n].innerHTML="<font color='"+coltoday+"'>"+str.toString()+"</font>"
			}
			else {
				daycell[n].innerHTML=curday
			}
			setday(n,month,year,curday);
			startingPos++
			curday++
		}
		else {	
  			if (startingPos==66){
				setday(n,month+1,year,curday);
				str=curday
 				curday++
			}
			else {
				setday(n,month-1,year,prevdays-startingPos+n+1);
				str=prevdays-startingPos+n+1
			}
			daycell[n].innerHTML="<font color='"+colour+"'>"+str.toString()+"</font>"
		}
		if (curday>days){
			curday=1
			startingPos=66
		}
	}
}

//Set day variables function
function setday(cell,month,year,day){
	month++
	if (month==13){month=1;year++}
	if (month==0){month=12;year--}

	var strmon;
	var stryear;
	var strday;

	strmon=month.toString();
	if (strmon.length==1){strmon="0"+strmon}
	strday=day.toString();
	if (strday.length==1){strday="0"+strday}
	stryear=year.toString();
	cellday[cell]=strday+strmon+stryear
}

//Function to check number of days in a month
function monthdays(month,year)  {
	var days;
	if (month==0 || month==2 || month==4 || month==6 || month==7 || month==9 || month==11 || month==-1 || month==12)  days=31;
	else if (month==3 || month==5 || month==8 || month==10) days=30;
	else if (month==1)  {
		if (leapyear(year)) { days=29; }
		else { days=28; }
	}
	return (days);
}

//Leap year checking function
function leapyear (Year) {
	if (((Year % 4)==0) && ((Year % 100)!=0) || ((Year % 400)==0)){
		return (true);
	} 
	else {
		return (false);
	}
}

//Display toggle functions
function goonmonth(){
	month = eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex;
	month++;
	if (month==12){
		month=0;
		goonyear();
	}
	eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex=month;
}

function goonyear(){
	year = eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value;
	year++;
	if (year==lastyear){year=firstyear}
	eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value=year;
}

function gobackmonth(){
	month = eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex;
	month--;
	if (month==-1){
		month=11;
		gobackyear();
	}
	eval('document.' + cal_formname + '.calmonth_' + thecaldiv.id).selectedIndex=month;
}

function gobackyear(){
	year  = eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value;
	year--;
	if (year<firstyear){year=lastyear-1}
	eval('document.' + cal_formname + '.calyear_' + thecaldiv.id).value=year;
}

///////////////////////////////////////////////////////////////////////////////////
//THE ACTUAL INTERFACE TO THE CALENDAR STARTS HERE								 //
///////////////////////////////////////////////////////////////////////////////////
//Vars for the storage of the currently open calendar
var cal_formname = '';
var cal_textboxname = '';
var cal_divname = '';
var thecalspan;
var thecaldiv;

/*
The entry point function
Parameters :	nameOfForm
				nameOfTextBoxContainingDate
				divTagObject
				displaySpanShowingSelectedDate
*/
function showCalendar(form,textbox,div,span,gridmode){
	var proceedflag = false;
	//If a calendar is currently open...try this...
	if (thecaldiv){
		//...if it the same calendar trying to close itself,allow it to...
		if (thecaldiv.id == div.id){
			proceedflag = true;
		}
	}
	else {
		//else no calendar is open Open it
		proceedflag = true;
	}
	if (proceedflag) {
		//Set the current calendar div as active
		thecaldiv = div;
		//If it was hidden show it and load it..
		if (div.style.display == 'none'){
			div.style.display = '';
			cal_formname = form;
			cal_textboxname = textbox;
			cal_divname = div.id;
			thecalspan = span;
			calendar(div,gridmode);
		}
		//...else hide it and unload the calendar.
		else {
			div.innerHTML == '';
			div.style.display = 'none';
			cal_formname = '';
			cal_textboxname = '';
			cal_divname = '';
			thecalspan = null;
			thecaldiv = null;
		}
	}
	else {
		alert("Please close the other open calendar first.");
	}
}

//Wrapping handler for a speficic date click event.
function message(cell,div,gridmode){
	storeSelectedDate(cellday[cell],div,gridmode);
}

//The function used to save the selected date to the specified textbox.
function storeSelectedDate(date,div,gridmode){
	var formattedDate = date.substr(0,2) + "-" + nameMonth(date.substr(2,2)) + "-" + date.substr(4,4);
	try {
		if (gridmode) {
			document.getElementById(cal_textboxname).value = formattedDate;
		}
		else {
			eval('document.' + cal_formname + '.' + cal_textboxname + '.value="' + formattedDate + '"');
			thecalspan.innerHTML = formattedDate;
		}
		showCalendar(cal_formname,cal_textboxname,div,thecalspan);
	}
	catch (ex){
		alert(ex.message);
	}
}

//Fuction returns the first three letters of month
function nameMonth(month){
      switch (month){
            case '01': return "Jan"; 
            case '02': return "Feb";
            case '03': return "Mar"; 
            case '04': return "Apr";
            case '05': return "May";
            case '06': return "Jun";
            case '07': return "Jul";
            case '08': return "Aug";
            case '09': return "Sep";
            case '10': return "Oct";
            case '11': return "Nov";
            case '12': return "Dec";
      }
}