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){
	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var pos2=dtStr.indexOf(dtCh,pos1+1)
	var strMonth=dtStr.substring(0,pos1)
	var strDay=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)
	}
	*/
	
	if (strYear.length ==2){
		if (strYear <= '20'){
			strYear = '20' + strYear
		}
		else
			strYear = '19' + strYear
	}
	
	
	month=parseInt(strMonth)
	day=parseInt(strDay)
	year=parseInt(strYear)
	
	
	
	if (pos1==-1 || pos2==-1){
		alert(' -1');
		alert("The date format should be : mm/dd/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 FilterData(e) {
	for (i=0; i<(document.forms[0].elements.length); i++) 
	{
	if (e.target == document.forms[0].elements["shares"+i])
		return FilterNumNN(e)
	if (e.target == document.forms[0].elements["tid"+i])
		return FilterNumNN(e)
	if (e.target == document.register_two.elements["Odenom"+i])
		return FilterNumNN(e)
	if (e.target == document.register_two.elements["num_shares"+i])
		return FilterNumNN(e)
	}
}
function compareDates(sFrom, sTo)
{
	fromDate = new Date(sFrom)
	toDate = new Date(sTo)
	//alert(fromDate);
	//alert(toDate);
	
	if (fromDate > toDate){
		alert ("The date range is invalid!")
		return false;
	}
	return true;
}

function isValidDate(formname,elementname)
{
	//alert(document.forms[formname].elements[elementname].value);
	if (!(checkdate(document.forms[formname].elements[elementname].value)))		  	
		{
		return false;
		}					
	return true;
}


function checkdate(date)
{
	if ( !isDate(date) )
		{
		return false;
		}
	return true;
}


function doDateCheck(from, to) {	
	//var dateFrom = new Date(from.substring(6,10),
    //                        from.substring(0,2)-1,
    //                        from.substring(3,5));
	var dateFrom = new Date(from)
	
	//var dateEnd = new Date(to.substring(6,10),
    //                        to.substring(0,2)-1,
    //                        to.substring(3,5));
	var dateEnd = new Date(to)
	
	
	if (dateFrom <= dateEnd)
        return true;
    else{
		alert("To date must occur after the From date.");
        return false;
    }
}


function after20041201(from, to) {
	
	//var dateFrom = new Date(from.substring(6,10),
    //                        from.substring(0,2)-1,
    //                        from.substring(3,5));

	var dateFrom = new Date(from)
			
	//var dateEnd = new Date(to.substring(6,10),
    //                        to.substring(0,2)-1,
    //                        to.substring(3,5));
	var dateEnd = new Date(to)
	
	if (dateFrom >= dateEnd)
        return true;
    else{
		alert("The from date has to be 12/01/2004 or after.");
        return false;
    }
}


function after20060106(from, to) {
	
	//var dateFrom = new Date(from.substring(6,10),
    //                        from.substring(0,2)-1,
    //                        from.substring(3,5));

	var dateFrom = new Date(from)
			
	//var dateEnd = new Date(to.substring(6,10),
    //                        to.substring(0,2)-1,
    //                        to.substring(3,5));
	var dateEnd = new Date(to)
	
	if (dateFrom >= dateEnd)
        return true;
    else{
		alert("The from date has to be 01/06/2006 or after.");
        return false;
    }
}
//Check for date entered, must not be greater than current date
function nofuturedate(formname,elementname) {
	var str_newdate = new Date(document.forms[formname].elements[elementname].value)
	var str_currdate = new Date()	
	if (str_newdate <= str_currdate)
        return true;
    else{
		alert("Date has to be on or before current date.");
        return false;
    }
}




function checkFutureDate(date,currentdate)
{
	if ( !isDate(date) ){
		return false;
	}
		
	objdate=new Date(date);
	objcurrentdate= new Date(currentdate);
	if ( objdate>objcurrentdate)
	{
		alert("This date is in the future.");
		return false;
	}
	
	return true;
}