var dtCh = "/";
var minYear = 1900;

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 isValidDate(dtStr, checkforMaxYear) {
    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;

    var today = new Date();
    maxYear = today.getFullYear();

    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 (checkforMaxYear == true) {
        if (strYear.length != 4 || year == 0 || year < minYear || year > maxYear) {
           // alert("Please enter a valid 4 digit year between " + minYear + " and " + maxYear);
            return false;
        }
    }
    else {
        if (strYear.length != 4 || year == 0 || year < minYear) {
          //  alert("Please enter a valid 4 digit year greater than " + minYear);
            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 validateDate(sender, args) {
    if (isValidDate(args.Value, false) == false)
        args.IsValid = false;
    else
        args.IsValid = true;
    return;
}

function validateAge(sender, args) {
   // alert("in function");
    // first make sure its a valid date
    //alert(args.Value);
    if (isValidDate(args.Value, false) == false) {
        args.IsValid = false;
        return;
    }

    try {

        // now make sure > 21 years old
        var bDate3 = new Date(args.Value);
        var todayDate = new Date();

        var year = bDate3.getFullYear();
        var month = bDate3.getMonth();
        var day = bDate3.getDate();

        // min age 21
        var date1 = new Date((year + 21), month, day);
        //Are they old enough?
        if ((todayDate.getTime() - date1.getTime()) < 0) {
            //alert("too young");
            args.IsValid = false;
            return;
        }
        else {
            //They are old enough
            //alert("good");  
            args.IsValid = true;
            return;
        }

    }
    catch (err) {
        //alert('not date');
        args.IsValid = false;
        return;
    }
}

function isValidExpDate(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;

    var today = new Date();
    maxYear = today.getFullYear();
    //minYear = today.getFullYear() - 1;

    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) {
       // alert("Please enter a valid 4 digit year greater than " + minYear);
        return false;
    }

    if (dtStr.indexOf(dtCh, pos2 + 1) != -1 || isInteger(stripCharsInBag(dtStr, dtCh)) == false) {
       // alert("Please enter a valid date");
        return false;
    }
    if (Date.parse(dtStr) <= Date.parse(today)) {
       // alert("Date must be greater than today");
        return false;
    }
    return true
}

function validateExpIDDate(sender, args) {
    
    if (isValidExpDate(args.Value) == false) {
        args.IsValid = false;
        return;
    }
    else {
        args.IsValid = true;
        return;
    }
}