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

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)
    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 : 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
    }
    return true
}

function validate(frm) {


    var errcode = 0;
    var filter = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
    var msg = "";
    var fullmsg = "";
    var msgReq = " - The following field(s) are required:\n";
    var Titlemsg = "_________________________________________________\n\n";
    Titlemsg += "The following error(s) were detected within your application.\n";
    Titlemsg += "Please correct these error(s) and re-submit the application.\n";
    Titlemsg += "_________________________________________________\n\n";

    fullmsg = Titlemsg;
    if (frm.name.value == "" || frm.name.value == "Name") {
        msg += "\tName\n";
        if (errcode == 0)
            errcode = 1;
    }
    if (frm.email.value == "" || frm.email.value == "Email") {
        msg += "\tEmail address\n";
        if (errcode == 0)
            errcode = 2;
    } else {
        if (!filter.test(frm.email.value)) {
            msg += "\n - The email entered is not in a valid format\n"
            if (errcode == 0)
                errcode = 2;
        }
    }
    if (frm.Telephone.value == "" || frm.Telephone.value == "Telephone") {
        msg += "\tTelephone Number\n";
        if (errcode == 0)
            errcode = 3;
    }
    if (frm.Comments.value == "" || frm.Comments.value == "Please enter your comments") {
        msg += "\tComments\n";
        if (errcode == 0)
            errcode = 4;
    }

    if (errcode != 0) {
        switch (errcode) {
            case 1:
                fullmsg += msgReq + msg;
                frm.name.focus();
                break
            case 2:
                fullmsg += msgReq + msg;
                frm.email.focus();
                break;
            case 3:
                fullmsg += msgReq + msg;
                frm.Telephone.focus();
                break;
            case 4:
                fullmsg += msgReq + msg;
                frm.Comments.focus();
                break;

        }
        alert(fullmsg);
        return false;
    } else {
        return true;
    }

}