function validateDateSelection(dayPart, monthPart, yearPart, fName, langOpt) {

    var fromDate = "";
    var toDate = "";


    if ( parseInt(dayPart, 10) > totalDaysInMonth(parseInt(monthPart, 10)-1, parseInt(yearPart, 10)) ) {
        if (langOpt == "el") {
            alert("Επιλέξατε μια ημερομηνία που δεν είναι έγκυρη για το πεδίο '" + fName + "'.\nΠαρακαλώ δοκιμάστε ξανά.\n\n");
        }else{
            alert("Invalid date selection for field '" + fName + "'.\nPlease try again.\n\n");
        }
    }

}

function populateHiddenDates() {

    var fDate = "";
    var tDate = "";

    var fDay = document.getElementById('fDay').options[document.getElementById('fDay').selectedIndex].value;
    var fMonth = document.getElementById('fMonth').options[document.getElementById('fMonth').selectedIndex].value;
    var fYear = document.getElementById('fYear').options[document.getElementById('fYear').selectedIndex].value;

    var tDay = document.getElementById('tDay').options[document.getElementById('tDay').selectedIndex].value;
    var tMonth = document.getElementById('tMonth').options[document.getElementById('tMonth').selectedIndex].value;
    var tYear = document.getElementById('tYear').options[document.getElementById('tYear').selectedIndex].value;

    if (parseInt(fDay, 10) < 10) {
        fDate = fDate + "0" + fDay + "/"; 
    }else{
        fDate = fDate + fDay + "/";
    }

    if (parseInt(fMonth, 10) < 10) {
        fDate = fDate + "0" + fMonth + "/"; 
    }else{
        fDate = fDate + fMonth + "/";
    }

    fDate = fDate + fYear; 

    if (parseInt(tDay, 10) < 10) {
        tDate = tDate + "0" + tDay + "/"; 
    }else{
        tDate = tDate + tDay + "/";
    }

    if (parseInt(tMonth, 10) < 10) {
        tDate = tDate + "0" + tMonth + "/"; 
    }else{
        tDate = tDate + tMonth + "/";
    }

    tDate = tDate + tYear;

    document.getElementById('fDate').value = fDate;  
    document.getElementById('tDate').value = tDate;
    //alert(fDate);
    //alert(tDate);

}

function totalDaysInMonth (intMonth, intYear) {
    var dInMonth;

    if ( (intMonth == 3) || (intMonth == 5) || (intMonth == 8) || (intMonth == 10) ) { 
		dInMonth = 30;
  	}else if (intMonth == 1) {
        if (isLeapYear(intYear)) {
            dInMonth = 29;
        }else{
            dInMonth = 28;
        }
    }else{
        dInMonth = 31;
    }
    return dInMonth;
}

function isLeapYear(intYear) {
	if (intYear % 100 == 0) 
	{
		if (intYear % 400 == 0) { return true; }
	}
	else 
	{
		if ((intYear % 4) == 0) { return true; }
	}	
	return false;
}