sAlert = "";
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function validateform()
{

	theForm = document.forms[0];

	if (theForm.elements['arvcountry'][theForm.elements['arvcountry'].selectedIndex].value == '')
	{
		sAlert+="Please specify a destination country.\n";
	}

	if (theForm.elements['arv'][theForm.elements['arv'].selectedIndex].value == '')
	{
		sAlert+="Please specify a destination airport.\n";
	}

	if (theForm.elements['dpt'][theForm.elements['dpt'].selectedIndex].value == '')
	{
		sAlert+="Please specify a departure region.\n";
	}

	if (theForm.elements['dptCounty'][theForm.elements['dptCounty'].selectedIndex].value == '')
	{
		sAlert+="Please specify a depature airport.\n";
	}

var sReturnDate = theForm.elements['flight-finder-return-day-control'][theForm.elements['flight-finder-return-day-control'].selectedIndex].value + '/' + theForm.elements['flight-finder-return-month-control'][theForm.elements['flight-finder-return-month-control'].selectedIndex].value + '/' + theForm.elements['flight-finder-return-year-control'][theForm.elements['flight-finder-return-year-control'].selectedIndex].value;

var sDepartureDate = theForm.elements['flight-finder-departure-day-control'][theForm.elements['flight-finder-departure-day-control'].selectedIndex].value + '/' + theForm.elements['flight-finder-departure-month-control'][theForm.elements['flight-finder-departure-month-control'].selectedIndex].value + '/' + theForm.elements['flight-finder-departure-year-control'][theForm.elements['flight-finder-departure-year-control'].selectedIndex].value;


	if (isDate(sReturnDate) == false && sReturnDate != '//') {
			sAlert+="Invalid return date\n";
	}

	if (isDate(sDepartureDate) == false) {
			sAlert+="Invalid departure date\n";
	}



	if (sAlert!=""){
		alert(sAlert);
		sAlert="";
		return false;
	}
	else
	{
		return true;
	}

}



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)
	strDay=dtStr.substring(0,pos1)
	strMonth=dtStr.substring(pos1+1,pos2)
	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 : 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;
	}
	
	now = new Date();

	if (parseInt(now.getFullYear()) > year ) {
		return false;
	}

	if (parseInt(now.getFullYear()) == year && parseInt(now.getMonth()) > month) {
		return false;
	}

	if (parseInt(now.getFullYear()) == year && parseInt(now.getMonth()) == month && parseInt(now.getDate()) > day){
		return false;
	}


	return true;
}

function CalcAge(fromdd,frommm,fromyy,todd,tomm,toyy) {
	age = toyy - fromyy;
	if((frommm == (tomm)) && (fromdd <= todd)) {
		age = age;
	}
	else {
		if(frommm < tomm) {
			age = age;
		}
		else {
			age = age - 1; 
   		}
   	}

	return age;
}