var winCal;
var isOpen=false;
var dtToday=new Date();
var Cal;
var docCal;
var MonthName=["Январь", "Февраль", "Март", "Апрель", "Май", "Июнь", "Июль", "Август", "Сентябрь", "Октябрь", "Ноябрь", "Декабрь"];
//var MonthName=["jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sept", "oct", "nov", "dec"];
var WeekDayName=["Вс","Пн","Вт","Ср","Чт","Пт","Сб"];	
///var WeekDayName=["Su","Mn","Tu","Wd","Th","Fr","Sa"];		
var exDateTime;//Existing Date and Time


//Configurable parameters
var cnTop=0;//top coordinate of calendar window.
var cnLeft=0;//left coordinate of calendar window
var WindowTitle ="Выбор даты";//Date Time Picker title.
//var WindowTitle ="Date Picker";//Date Time Picker title.
var WeekChar=2;//number of character for week day. if 2 then Mo,Tu,We. if 3 then Mon,Tue,Wed.
var CellWidth=20;//Width of day cell.
var DateSeparator="-";//Date Separator, you can change it to "/" if you want.
var TimeMode=24;//default TimeMode value. 12 or 24
var ShowSeconds=1;//default value (shows seconds if the time ShowTime is on)
var ShowLongMonth=true;//Show long month name in Calendar header. example: "January".
var ShowMonthYear=true;//Show Month and Year in Calendar header.

var MonthYearClass="txtRed";//Font Color of Month and Year in Calendar header.

var WeekHeadColor="#336699";//Background Color in Week header.
var WeekHeadFontClass="txtWhite";//Background Color in Week header.

var SundayColor="#AACCFF";//Background color of Sunday.
var SaturdayColor="#BBDDFF";//Background color of Saturday.
var YrSelColor="#990000";//color of font of Year selector.
var BackgroundColor="#E4E7EB";//Background color of window 

var WeekDayColor="white";//Background color of weekdays.
var FontColor="#333333";//color of font in Calendar day cell.
var TodayColor="#FFFF33";//Background color of today.
var SelDateColor="#FFFF99";//Background color of selected date in textbox.

var ThemeBg="";//Background image of Calendar window.
//end Configurable parameters

//Configurable parameters initial
var MonthYearColor="white";//Font Color of Month and Year in Calendar header.
//end Configurable parameters
//end Global variable

function runDatePicker(pCtrl,pFormat,pShowTime,pTimeMode,pSeparator)
{
    if (pShowTime == 'false' ||  pShowTime == 'False' || pShowTime == '0') {
    pShowTime = null;
    }
    
	var lefter = (screen.width / 2) - 100;
    var topper = (screen.height / 2) - 100;

	NewCal(pCtrl,pFormat,pShowTime,pTimeMode,pSeparator,lefter,topper);
}

function NewCal(pCtrl,pFormat,pShowTime,pTimeMode,pSeparator,pLeft,pTop)
{
	Cal=new Calendar(dtToday);
	cnLeft=pLeft;
	cnTop=pTop;
	if (pSeparator!=null)
	{
		DateSeparator=pSeparator;
	}
	if ((pShowTime!=null) && (pShowTime))
	{
		Cal.ShowTime=true;
		if ((pTimeMode!=null) &&((pTimeMode=='12')||(pTimeMode=='24')))
		{
			TimeMode=pTimeMode;
			if((pFormat!=null) && (pFormat=='DDMMYYYY_HHMM'))
			{
				Cal.ShowSeconds=false;
			}
		}		
	}	
	if (pCtrl!=null)
		Cal.Ctrl=pCtrl;
	if (pFormat!=null)
		Cal.Format=pFormat.toUpperCase();
	
	exDateTime=document.getElementById(pCtrl).value;
	if (exDateTime!="")//Parse Date String
	{
		var Sp1;//Index of Date Separator 1
		var Sp2;//Index of Date Separator 2 
		var tSp1;//Index of Time Separator 1
		var tSp1;//Index of Time Separator 2
		var strMonth;
		var strDate;
		var strYear;
		var intMonth;
		var YearPattern;
		var strHour;
		var strMinute;
		var strSecond;
		//parse month
		Sp1=exDateTime.indexOf(DateSeparator,0)
		Sp2=exDateTime.indexOf(DateSeparator,(parseInt(Sp1)+1));
		
		if ((Cal.Format.toUpperCase()=="DDMMYYYY") || (Cal.Format.toUpperCase()=="DDMMMYYYY") || (Cal.Format.toUpperCase()=="DDMMYYYY_HHMM") || (Cal.Format.toUpperCase()=="DDMMYYYY_HHMMSS"))
		{
			strMonth=exDateTime.substring(Sp1+1,Sp2);
			strDate=exDateTime.substring(0,Sp1);
			
		}
		else if ((Cal.Format.toUpperCase()=="MMDDYYYY") || (Cal.Format.toUpperCase()=="MMMDDYYYY"))
		{
			strMonth=exDateTime.substring(0,Sp1);
			strDate=exDateTime.substring(Sp1+1,Sp2);
		}
		if (isNaN(strMonth))
			intMonth=Cal.GetMonthIndex(strMonth);
		else
			intMonth=parseInt(strMonth,10)-1;	
		if ((parseInt(intMonth,10)>=0) && (parseInt(intMonth,10)<12))
			Cal.Month=intMonth;
		//end parse month
		//parse Date
		if ((parseInt(strDate,10)<=Cal.GetMonDays()) && (parseInt(strDate,10)>=1))
			Cal.Date=strDate;
			
		//end parse Date
		//parse year
		strYear=exDateTime.substring(Sp2+1,Sp2+5);
		YearPattern=/^\d{4}$/;
		if (YearPattern.test(strYear))
			Cal.Year=parseInt(strYear,10);
		//end parse year
		//parse time
		if (Cal.ShowTime==true)
		{
			tSp1=exDateTime.indexOf(":",0)
			tSp2=exDateTime.indexOf(":",(parseInt(tSp1)+1));
			strHour=exDateTime.substring(tSp1,(tSp1)-2);
			Cal.SetHour(strHour);
			strMinute=exDateTime.substring(tSp1+1,tSp2);
			Cal.SetMinute(strMinute);
			//if(Cal.ShowSeconds==true)
			//{
				strSecond=exDateTime.substring(tSp2+1,tSp2+3);
				Cal.SetSecond(strSecond);
			//}
		}	
	}
	if (isOpen) {
		CloseWinCal();
		//winCal.focus();
	}
	winCal=window.open("","","toolbar=0,status=0,menubar=0,fullscreen=0,width=200,height=200,resizable=0,top="+cnTop+",left="+cnLeft);
	isOpen=true;
	docCal=winCal.document;
	RenderCal();

	// keep winCal on top
	//var ontopIntervalHandle = winCal.setInterval("window.opener.winCal.focus();", 1000);
	//window.clearInterval(ontopIntervalHandle);
	window.onbeforeunload = function() {CloseWinCal();};
	document.body.onbeforeunload = function() {CloseWinCal();};
}
function SetWinCalFalse() {isOpen=false;}
function CloseWinCal() {if (isOpen) {winCal.close();SetWinCalFalse();}}

function RenderCal()
{
	var vCalHeader;
	var vCalData;
	var vCalTime;
	var i;
	var j;
	var SelectStr;
	var vDayCount=0;
	var vFirstDay;

	docCal.open();
	docCal.writeln("<html><head><title>"+WindowTitle+"</title>");
	docCal.writeln("<script>");
	docCal.writeln("<!--");
	docCal.writeln("var winMain=window.opener;");
	//docCal.writeln("window.onbeforeunload = function() {winMain.SetWinCalFalse();}");
	docCal.writeln("function checkForEnter()");
	docCal.writeln("{");
	docCal.writeln("var evt = (evt) ? evt : window.event;");
	docCal.writeln("var charCode = (evt.which) ? evt.which : evt.keyCode;");
	docCal.writeln("if (charCode == 13) {");
	docCal.writeln("var hour = document.getElementById('hour');");
	docCal.writeln("if (hour!=null)");
	docCal.writeln("winMain.Cal.SetHour(document.getElementById('hour').value);");
	docCal.writeln("var min = document.getElementById('minute');");
	docCal.writeln("if (min!=null)");
	docCal.writeln("winMain.Cal.SetMinute(document.getElementById('minute').value);");
	docCal.writeln("winMain.document.getElementById('"+Cal.Ctrl+"').value=winMain.Cal.getSelectedDate();");
	docCal.writeln("window.close();");
	docCal.writeln("}");
	docCal.writeln("return true");
	docCal.writeln("}")
	docCal.writeln("-->");
	docCal.writeln("</script>");
	docCal.writeln("<style type='text/css'>");
	docCal.writeln("<!--");
	docCal.writeln("body {margin-left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px;}");
	docCal.writeln("-->");
	docCal.writeln("</style>");
	docCal.writeln("</head><body onKeyPress='checkForEnter()' bgcolor='"+BackgroundColor+"' background='"+ThemeBg+"' link="+FontColor+" vlink="+FontColor+"><form name='Calendar'>");
	vCalHeader="<table border=0 cellpadding=1 cellspacing=1 width='100%' align=\"center\" valign=\"top\">\n";
	//Month Selector
	vCalHeader+="<tr>\n<td colspan='7'><table border=0 width='100%' cellpadding=0 cellspacing=0><tr><td align='left'>\n";
	vCalHeader+="<select name=\"MonthSelector\" onChange=\"javascript:winMain.Cal.SwitchMth(this.selectedIndex);winMain.RenderCal();\">\n";
	for (i=0;i<12;i++)
	{
		if (i==Cal.Month)
			SelectStr="Selected";
		else
			SelectStr="";	
		vCalHeader+="<option "+SelectStr+" value >"+MonthName[i]+"\n";
	}
	vCalHeader+="</select></td>";
	//Year selector
	vCalHeader+="\n<td align='right'><a href=\"javascript:winMain.Cal.DecYear();winMain.RenderCal()\"><b><font color=\""+YrSelColor+"\"><</font></b></a><font face=\"Verdana\" color=\""+YrSelColor+"\" size=2><b> "+Cal.Year+" </b></font><a href=\"javascript:winMain.Cal.IncYear();winMain.RenderCal()\"><b><font color=\""+YrSelColor+"\">></font></b></a>&nbsp;&nbsp;</td></tr></table></td>\n";	
	//vCalHeader+="\n<td align='right'><input type=submit onClick=\"javascript:winMain.document.getElementById('"+Cal.Ctrl+"').value='"+Cal.getToday()+"';"+vTimeStr+";winMain.Cal.loseFocus(winMain);window.close();\" value='OK'></td>\n";
	vCalHeader+="</tr>";
	//Calendar header shows Month and Year
	if (ShowMonthYear)
		vCalHeader+="<tr><td colspan='7'><font face='Verdana' size='2' align='center' color='"+MonthYearColor+"'><b>"+Cal.GetMonthName(ShowLongMonth)+" "+Cal.Year+"</b></font></td></tr>\n";
	//Week day header
	vCalHeader+="<tr bgcolor="+WeekHeadColor+">";
	for (i=0;i<7;i++)
	{
		vCalHeader+="<td align='center'><font face='Verdana' size='2'>"+WeekDayName[i].substr(0,WeekChar)+"</font></td>";
	}
	vCalHeader+="</tr>";	
	docCal.write(vCalHeader);
	
	//Calendar detail
	CalDate=new Date(Cal.Year,Cal.Month);
	CalDate.setDate(1);
	vFirstDay=CalDate.getDay();
	vCalData="<tr>";
	for (i=0;i<vFirstDay;i++)
	{
		vCalData=vCalData+GenCell();
		vDayCount=vDayCount+1;
	}
	for (j=1;j<=Cal.GetMonDays();j++)
	{
		var strCell;
		vDayCount=vDayCount+1;
		if ((j==dtToday.getDate())&&(Cal.Month==dtToday.getMonth())&&(Cal.Year==dtToday.getFullYear()))
			strCell=GenCell(j,true,TodayColor);//Highlight today's date
		else
		{
			if (j==Cal.Date)
			{
				strCell=GenCell(j,true,SelDateColor);
			}
			else
			{	 
				if (vDayCount%7==0)
					strCell=GenCell(j,false,SaturdayColor);
				else if ((vDayCount+6)%7==0)
					strCell=GenCell(j,false,SundayColor);
				else
					strCell=GenCell(j,null,WeekDayColor);
			}		
		}						
		vCalData=vCalData+strCell;

		if((vDayCount%7==0)&&(j<Cal.GetMonDays()))
		{
			vCalData=vCalData+"</tr>\n<tr>";
		}
	}
	docCal.writeln(vCalData);	
	//Time picker
	if (Cal.ShowTime)
	{
		var showHour;
		showHour=Cal.getShowHour();		
		vCalTime="<tr>\n<td colspan='7' align='center'>";
		vCalTime+="<input type='text' name='hour' maxlength=2 size=1 style=\"WIDTH: 22px\" value="+showHour+" onchange=\"javascript:winMain.Cal.SetHour(this.value)\" >";
		vCalTime+=" : ";
		vCalTime+="<input type='text' name='minute' maxlength=2 size=1 style=\"WIDTH: 22px\" value="+Cal.Minutes+" onchange=\"javascript:winMain.Cal.SetMinute(this.value)\" >";
		if(Cal.ShowSeconds)
		{
			vCalTime+=" : ";
			vCalTime+="<input  type='text' name='second' maxlength=2 size=1 style=\"WIDTH: 22px\" value="+Cal.Seconds+" onchange=\"javascript:winMain.Cal.SetSecond(this.value)\">";
		}
		if (TimeMode==12)
		{
			var SelectAm =(parseInt(Cal.Hours,10)<12)? "Selected":"";
			var SelectPm =(parseInt(Cal.Hours,10)>=12)? "Selected":"";

			vCalTime+="<select name=\"ampm\" onchange=\"javascript:winMain.Cal.SetAmPm(this.options[this.selectedIndex].value);\">";
			vCalTime+="<option "+SelectAm+" value=\"AM\">AM</option>";
			vCalTime+="<option "+SelectPm+" value=\"PM\">PM<option>";
			vCalTime+="</select>";
		}	
		vCalTime+="\n</td>\n</tr>";
		docCal.write(vCalTime);
	}	
	//end time picker
	docCal.writeln("\n</table>");
	docCal.writeln("</form></body></html>");
	docCal.close();
}

function GenCell(pValue,pHighLight,pColor)//Generate table cell with value
{
	var PValue;
	var PCellStr;
	var vColor;
	var vHLstr1;//HighLight string
	var vHlstr2;
	var vTimeStr;
	
	if (pValue==null)
		PValue="";
	else
		PValue=pValue;
	//alert(pValue);
	if (pColor!=null)
		vColor="bgcolor=\""+pColor+"\"";
	else
		vColor="";	
	if ((pHighLight!=null)&&(pHighLight))
		{vHLstr1="color='red'><b>";vHLstr2="</b>";}
	else
		{vHLstr1=">";vHLstr2="";}	
	
	if (Cal.ShowTime)
	{
		if(Cal.ShowSeconds)
		{
			vTimeStr="winMain.document.getElementById('"+Cal.Ctrl+"').value+=' '+"+"winMain.Cal.getShowHour()"+"+':'+"+"winMain.Cal.Minutes"+"+':'+"+"winMain.Cal.Seconds";
		}
		else
		{
			vTimeStr="winMain.document.getElementById('"+Cal.Ctrl+"').value+=' '+"+"winMain.Cal.getShowHour()"+"+':'+"+"winMain.Cal.Minutes";
		}

		if (TimeMode==12)
			vTimeStr+="+' '+winMain.Cal.AMorPM";
	}	
	else
		vTimeStr="";
			//alert(Cal.FormatDate(PValue));
	PCellStr="<td "+vColor+" width="+CellWidth+" align='center'><font face='verdana' size='2'"+vHLstr1+"<a href=\"javascript:winMain.document.getElementById('"+Cal.Ctrl+"').value='"+Cal.FormatDate(PValue)+"';"+vTimeStr+";winMain.Cal.loseFocus(winMain);window.close();\">"+PValue+"</a>"+vHLstr2+"</font></td>";
	return PCellStr;
}

function Calendar(pDate,pCtrl)
{
	//Properties
	this.Date=pDate.getDate();//selected date
	this.Month=pDate.getMonth();//selected month number
	this.Year=pDate.getFullYear();//selected year in 4 digits
	this.Hours=pDate.getHours();
		
	if (pDate.getMinutes()<10)
		this.Minutes="0"+pDate.getMinutes();
	else
		this.Minutes=pDate.getMinutes();
	
	if (pDate.getSeconds()<10)
		this.Seconds="0"+pDate.getSeconds();
	else		
		this.Seconds=pDate.getSeconds();
		
	this.MyWindow=winCal;
	this.Ctrl=pCtrl;
	this.Format="ddMMyyyy";
	this.Separator=DateSeparator;
	this.ShowTime=false;
	this.ShowSeconds=true;
	if (pDate.getHours()<12)
		this.AMorPM="AM";
	else
		this.AMorPM="PM";	
}
function getSelectedDate()
{
var selectedDate = Cal.FormatDate(Cal.getUnformattedDate(Cal.Date));
	if (this.Format.toUpperCase()=="DDMMYYYY_HHMM")
		selectedDate += ' ' + Cal.Hours + ':' + Cal.Minutes;	
	else if (this.Format.toUpperCase()=="DDMMYYYY_HHMMSS")
		selectedDate += ' ' + Cal.Hours + ':' + Cal.Minutes + ':' + Cal.Seconds;	

return selectedDate
}
Calendar.prototype.getSelectedDate=getSelectedDate;
function getUnformattedDate(dt)
{
	if (dt < 10)//Not display zeros in date
	{
		dt = Cal.deleteString(dt,"0");
		return dt
	}
	else
	return dt
}
Calendar.prototype.getUnformattedDate=getUnformattedDate;

function loseFocus(win)
{
	try
	{
		try {win.document.FormReg.txtDTimeDeparture.focus();}
		catch(ex3){}
		try {win.document.FormReg.txtDTimeArrival.focus();}
		catch(ex2){}
		try {win.document.FormReg.txtDTimeArrivalFact.focus();}
		catch(ex1){}
	}
	catch(ex)
	{
	//alert(ex);
	}
}
Calendar.prototype.loseFocus=loseFocus;

function GetMonthIndex(shortMonthName)
{
	for (i=0;i<12;i++)
	{
		if (MonthName[i].substring(0,3).toUpperCase()==shortMonthName.toUpperCase())
		{	return i;}
	}
}
Calendar.prototype.GetMonthIndex=GetMonthIndex;

function IncYear()
{	Cal.Year++;}
Calendar.prototype.IncYear=IncYear;

function DecYear()
{	Cal.Year--;}
Calendar.prototype.DecYear=DecYear;
	
function SwitchMth(intMth)
{	Cal.Month=intMth;}
Calendar.prototype.SwitchMth=SwitchMth;

function SetHour(intHour)
{	
	var MaxHour;
	var MinHour;
	if (TimeMode==24)
	{	MaxHour=23;MinHour=0}
	else if (TimeMode==12)
	{	MaxHour=12;MinHour=1}
	else
		alert("TimeMode can only be 12 or 24");		
	var HourExp=new RegExp("^\\d\\d$");
	if (HourExp.test(intHour) && (parseInt(intHour,10)<=MaxHour) && (parseInt(intHour,10)>=MinHour))
	{	
		if ((TimeMode==12) && (Cal.AMorPM=="PM"))
		{
			if (parseInt(intHour,10)==12)
				Cal.Hours=12;
			else	
				Cal.Hours=parseInt(intHour,10)+12;
		}	
		else if ((TimeMode==12) && (Cal.AMorPM=="AM"))
		{
			if (intHour==12)
				intHour-=12;
			Cal.Hours=parseInt(intHour,10);
		}
		else if (TimeMode==24)
			Cal.Hours=parseInt(intHour,10);	
	}
}
Calendar.prototype.SetHour=SetHour;

function SetMinute(intMin)
{
	var MinExp=new RegExp("^\\d\\d$");
	if (MinExp.test(intMin) && (intMin<60))
	{
		Cal.Minutes=intMin;
	}
}
Calendar.prototype.SetMinute=SetMinute;

function SetSecond(intSec)
{	
	var SecExp=new RegExp("^\\d\\d$");
	if (SecExp.test(intSec) && (intSec<60))
		Cal.Seconds=intSec;
}
Calendar.prototype.SetSecond=SetSecond;

function SetAmPm(pvalue)
{
	this.AMorPM=pvalue;
	if (pvalue=="PM")
	{
		this.Hours=(parseInt(this.Hours,10))+12;
		if (this.Hours==24)
			this.Hours=12;
	}	
	else if (pvalue=="AM")
		this.Hours-=12;	
}
Calendar.prototype.SetAmPm=SetAmPm;

function getShowHour()
{
	var finalHour;
    if (TimeMode==12)
    {
    	if (parseInt(this.Hours,10)==0)
		{
			this.AMorPM="AM";
			finalHour=parseInt(this.Hours,10)+12;	
		}
		else if (parseInt(this.Hours,10)==12)
		{
			this.AMorPM="PM";
			finalHour=12;
		}		
		else if (this.Hours>12)
		{
			this.AMorPM="PM";
			if ((this.Hours-12)<10)
				finalHour="0"+((parseInt(this.Hours,10))-12);
			else
				finalHour=parseInt(this.Hours,10)-12;	
		}
		else
		{
			this.AMorPM="AM";
			if (this.Hours<10)
				finalHour="0"+parseInt(this.Hours,10);
			else
				finalHour=this.Hours;	
		}
	}
	else if (TimeMode==24)
	{
		if (this.Hours<10)
			finalHour="0"+parseInt(this.Hours,10);
		else	
			finalHour=this.Hours;
	}	
	return finalHour;	
}				
Calendar.prototype.getShowHour=getShowHour;		

function GetMonthName(IsLong)
{
	var Month=MonthName[this.Month];
	if (IsLong)
		return Month;
	else
		return Month.substr(0,3);
}
Calendar.prototype.GetMonthName=GetMonthName;

function GetMonDays()//Get number of days in a month
{
	var DaysInMonth=[31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
	if (this.IsLeapYear())
	{
		DaysInMonth[1]=29;
	}	
	return DaysInMonth[this.Month];	
}
Calendar.prototype.GetMonDays=GetMonDays;

function IsLeapYear()
{
	if ((this.Year%4)==0)
	{
		if ((this.Year%100==0) && (this.Year%400)!=0)
		{
			return false;
		}
		else
		{
			return true;
		}
	}
	else
	{
		return false;
	}
}
Calendar.prototype.IsLeapYear=IsLeapYear;

function FormatDate(pDate)
{

var month; 
month = this.Month+1;
if (month < 10)//Display zeros in month
{month = "0" + month;}

if (pDate < 10)//Display zeros in date
{pDate = "0" + pDate;}


	if (this.Format.toUpperCase()=="DDMMYYYY")
		return (pDate+DateSeparator+(month)+DateSeparator+this.Year);
	else if (this.Format.toUpperCase()=="DDMMMYYYY")
		return (pDate+DateSeparator+this.GetMonthName(false)+DateSeparator+this.Year);
	else if (this.Format.toUpperCase()=="DDMMYYYY_HHMM")
		return (pDate+DateSeparator+(month)+DateSeparator+this.Year);	
	else if (this.Format.toUpperCase()=="DDMMYYYY_HHMMSS")
		return (pDate+DateSeparator+(month)+DateSeparator+this.Year);	
	else if (this.Format.toUpperCase()=="MMDDYYYY")
		return ((month)+DateSeparator+pDate+DateSeparator+this.Year);
	else if (this.Format.toUpperCase()=="MMMDDYYYY")
		return (this.GetMonthName(false)+DateSeparator+pDate+DateSeparator+this.Year);			
}
Calendar.prototype.FormatDate=FormatDate;

/*STRING FUNCTIONS*/

// extract front part of string prior to searchString
function getFront(mainStr,searchStr){
	foundOffset = mainStr.indexOf(searchStr)
	if (foundOffset == -1) {
		return null
	}
	return mainStr.substring(0,foundOffset)
}
Calendar.prototype.getFront=getFront;
// extract back end of string after searchString
function getEnd(mainStr,searchStr) {
	foundOffset = mainStr.indexOf(searchStr)
	if (foundOffset == -1) {
		return null
	}
	return mainStr.substring(foundOffset+searchStr.length,mainStr.length)
}
Calendar.prototype.getEnd=getEnd;
// insert insertString immediately before searchString
function insertString(mainStr,searchStr,insertStr) {
	var front = Cal.getFront(mainStr,searchStr)
	var end = Cal.getEnd(mainStr,searchStr)
	if (front != null && end != null) {
		return front + insertStr + searchStr + end
	}
	return null
}
Calendar.prototype.insertString=insertString;
// remove deleteString
function deleteString(mainStr,deleteStr) {
	return Cal.replaceString(mainStr,deleteStr,"")
}
Calendar.prototype.deleteString=deleteString;
// replace searchString with replaceString
function replaceString(mainStr,searchStr,replaceStr) {
	var front = Cal.getFront(mainStr,searchStr)
	var end = Cal.getEnd(mainStr,searchStr)
	if (front != null && end != null) {
		return front + replaceStr + end
	}
	return null
}
Calendar.prototype.replaceString=replaceString;
/*STRING FUNCTIONS END*/