function MakeError(element) {
			document.getElementById(element).style.background = '#ff0000';
			document.getElementById(element).style.color	  = '#FFFFFF';
			
	}
	
	function UnMakeError(element) {
			document.getElementById(element).style.background = '#FFFFFF';
			document.getElementById(element).style.color	  = '#000000';
	}
		
	function check_frm() {
		return (validate_frm());
	}

	function check_frm2(lang) {
	var wrn
		if (lang == 'EL') {
		wrn='Το όχημα αυτό δεν είναι διαθέσιμο για το συγκεκριμένο διάστημα ημερών';
		}
		else {
		wrn='This vehicle is not available for the specified period'
		}
		if (frm.chargerental.value == 0) {
		alert(wrn);
		return false;
		}
	}


	function check_frm3() {
		if (document.frm.fullname.value=='') {
			MakeError("fullname");
			return false;
		}
		if (document.frm.phone.value=='') {
			MakeError("phone");
			return false;
		}
		if (isValidEmail(frm.email.value)) {					
			UnMakeError("email");		
		} else 
		{
			MakeError("email");
			return false;	
		}
	}


	function validate_frm() {

		var hdate1 = new Date();
		var hdate2 = new Date();
		var now    = new Date();
		
			
		hdate1.setFullYear(frm.Year_from.value, frm.Month_from.value-1, frm.Day_from.value);
		hdate1.setHours(frm.Hour_from.value, frm.Min_from.value, 0, 0);	

		hdate2.setFullYear(frm.Year_to.value,   frm.Month_to.value-1,   frm.Day_to.value);
		hdate2.setHours(frm.Hour_to.value, frm.Min_to.value, 0, 0);	

		if (hdate1.getTime()<now.getTime()) {
			MakeError("Year_from");
			MakeError("Month_from");
			MakeError("Day_from");
			MakeError("Hour_from");
			MakeError("Min_from");
	    	frm.Day_from.focus();
	    	return false;
		} else
		{
			UnMakeError("Year_from");
			UnMakeError("Month_from");
			UnMakeError("Day_from");
			UnMakeError("Hour_from");
			UnMakeError("Min_from");
		}

		if (hdate2<now) {
			MakeError("Year_to");
			MakeError("Month_to");
			MakeError("Day_to");
			MakeError("Hour_to");
			MakeError("Min_to");
	    	frm.Day_to.focus();
	    	return false;
		} else
		{
			UnMakeError("Year_to");
			UnMakeError("Month_to");
			UnMakeError("Day_to");
			UnMakeError("Hour_to");
			UnMakeError("Min_to");
		}

		if (hdate1>hdate2) {
			// Senario 1: Date From > Date To
			MakeError("Year_to");
			MakeError("Month_to");
			MakeError("Day_to");
			MakeError("Hour_to");
			MakeError("Min_to");
	    	frm.Day_to.focus();
	    	return false;
		} else {
			UnMakeError("Year_to");
			UnMakeError("Month_to");
			UnMakeError("Day_to");
			UnMakeError("Hour_to");
			UnMakeError("Min_to");
		}		
		
		
		if (isValidDate(frm.Month_from.value+'/'+frm.Day_from.value+'/'+frm.Year_from.value, 'errorfrm') == false) {
			MakeError("Year_from");
			MakeError("Month_from");
			MakeError("Day_from");
			MakeError("Hour_from");
			MakeError("Min_from");
	    	frm.Day_from.focus();
			return false;	
		}
		
		if (isValidDate(frm.Month_to.value+'/'+frm.Day_to.value+'/'+frm.Year_to.value, 'errorto') == false) {
			MakeError("Year_to");
			MakeError("Month_to");
			MakeError("Day_to");
			MakeError("Hour_to");
			MakeError("Min_to");
			return false;	
		}

	}
	
function IsNumeric(sText)
{
   var ValidChars = "0123456789.";
   var IsNumber=true;
   var Char;

 
   for (i = 0; i < sText.length && IsNumber == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsNumber = false;
         }
      }
   return IsNumber; 
}

function isValidDate(dateStr, errorElement) {
// Checks for the following valid date formats:
// MM/DD/YY   MM/DD/YYYY   MM-DD-YY   MM-DD-YYYY
// Also separates date into month, day, and year variables


	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/;

	var matchArray = dateStr.match(datePat); // is the format ok?
	if (matchArray == null) {
		alert("Date is not in a valid format.");
		return false;
	}
	month = matchArray[1]; // parse date into variables
	day   = matchArray[3];
	year  = matchArray[4];
	
	if ((month==4 || month==6 || month==9 || month==11) && day==31) {
		document.getElementById(errorElement).innerHTML = '<font color="#FD750A"><b>You have selected an invalid date.</font>';
		return false;
	}
	if (month == 2) { // check for february 29th
		var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
		if (day>29 || (day==29 && !isleap)) {
			document.getElementById(errorElement).innerHTML = '<font color="#FD750A"><b>You have selected an invalid date.</font>';
			return false;
		}
	}
	return true;  // date is valid
}

function isValidEmail(str) {
   return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);
 
}