/**
 * DHTML date validation script for dd/mm/yyyy. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
 */
// Declaring valid date character, minimum year and maximum year
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function isInteger(s){
	var i;
    for (i = 0; i < s.length; i++){   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag){
	var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
	for (var i = 1; i <= n; i++) {
		this[i] = 31
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30}
		if (i==2) {this[i] = 29}
   } 
   return this
}

function isDate(dtStr){
	if(dtStr!=""){
		var daysInMonth = DaysArray(12)
		var pos1=dtStr.indexOf(dtCh)
		var pos2=dtStr.indexOf(dtCh,pos1+1)
		var strDay=dtStr.substring(0,pos1)
		var strMonth=dtStr.substring(pos1+1,pos2)
		var strYear=dtStr.substring(pos2+1)
		strYr=strYear
		if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
		if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
		for (var i = 1; i <= 3; i++) {
			if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
		}
		month=parseInt(strMonth)
		day=parseInt(strDay)
		year=parseInt(strYr)
		if (pos1==-1 || pos2==-1){
			alert("The date format should be : dd/mm/yyyy")
			return false
		}
		if (strMonth.length<1 || month<1 || month>12){
			alert("Please enter a valid month")
			return false
		}
		if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
			alert("Please enter a valid day")
			return false
		}
		if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
			alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
			return false
		}
		if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
			alert("Please enter a valid date")
			return false
		}
	}
return true
}

function ValidateForm(val){
	var dt=val;
	
	if (isDate(dt.value)==false){
		dt.value = "";
		//dt.focus()
		return false
	}else{
		var sd = dt.value;
		
		var ed = sd.split("/");
		var b  = ed[2];
		var a  = ed[1]-1;
		var c  = ed[0];
		var iDate = new Date(b,a,c);
     	var iToday = new Date();
		if(iDate > iToday)
	  	{
		alert("Date is  Greater than today's date");
		dt.value = "";
		return false
      	}
	}
    return true
 }
