// COMMON JS ROUTINES
// Function to Trim
function trim( val ) {
	return rTrim( lTrim( val ) );
}

function lTrim( val ) { // Trim leading spaces
	while( '' + val.charAt(0)==' ' ) {
		val = val.substring(1,val.length);
	}
	return val;
}

function rTrim( val ) {	// Trim trailing spaces
	while( '' + val.charAt(val.length-1)==' ') {
		val = val.substring(0,val.length-1)
	}
	return val;
}

// Validate E-Mail Address
function validateEmail(addr) {
	addr = trim(addr);
	
	var exclude=/[^@\-\.\w\_]|^[_@\.\-]|[\._\-]{2}|[@\.]{2}|(@)[^@]*\1/;
	var check=/@[\w\-]+\./;
	var checkend=/\.[a-zA-Z]{2,3}$/;
	var strEmail = addr;
	var checkEmail = "false";
	var email_array=strEmail.split(",");

	var email_num=0;

	while (email_num < email_array.length) { 
		var trimemail = trim(email_array[email_num]);
		if(((trimemail.search(exclude) != -1) || (trimemail.search(check)) == -1) || (trimemail.search(checkend) == -1)) {
			checkEmail = "false";
		} else {
			checkEmail = "true";
		}
		email_num++;

		if(checkEmail == "false") {
			return false;
		}
	}
	return true;
}

/**
 * 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;
// VALIDATE DATE: UTILITY 1
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;
}
// VALIDATE DATE : UTILITY : 2
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;
}
// VALIDATE DATE: UTILITY 3
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 );
}
// VALIDATE DATE: UTILITY 4
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;
}
// VALIDATE DATE : MAIN FUNCTION
function isDate(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;
}