// A Utility that returns true if a string contains only whitespace characters
function isblank(s) {
    for(var i = 0; i < s.length; i++) {
        var c = s.charAt(i);
        if ((c != ' ') && (c != '\n') && (c != '\t')) return false;
    }
    return true;
}

// A Utility to check password validity.
function chkpass(p) {
	var pmin = 8;
	var pmax = 16;
	
	//If ((p.length < pmin) || (p.length > pmax)) {
		alert (p.length)
	//}
		
}
	
// This is the function that performs form verification. It is invoked
// from the onsubmit event handler. The handler should return whatever
// value this function returns.
function verify(f) {
    var msg;
    var empty_fields = "";
    var errors = "";
	var pmin =8;
	var pmax=16;
	var init_pass ="";
	var conf_pass ="";

    // Loop through the elements of the form, looking for all 
    // text and textarea elements that don't have an "optional" property
    // defined. Then, check for fields that are empty and make a list of them.
    // Also, if any of these elements have a "min" or a "max" property defined,
    // verify that they are numbers and in the right range.
    // If the element has a "numeric" property defined, verify that
    // it is a number, but don't check its range.
    // Put together error messages for fields that are wrong.
    for(var i = 0; i < f.length; i++) {
        var e = f.elements[i];
        if (((e.type == "text") || (e.type == "textarea") || (e.type == "select-one")) && !e.optional) {
            //alert(e.name);
			// first check if the field is empty
            if ((e.value == null) || (e.value == "") || isblank(e.value)) {
                empty_fields += "\n          " + e.name;
                continue;
            }

            // Now check for fields that are supposed to be numeric.
            if (e.numeric || (e.min != null) || (e.max != null)) { 
                var v = parseFloat(e.value);
                if (isNaN(v) || 
                    ((e.min != null) && (v < e.min)) || 
                    ((e.max != null) && (v > e.max))) {
                    errors += "- The field " + e.name + " must be a number";
                    if (e.min != null) 
                        errors += " that is greater than " + e.min;
                    if (e.max != null && e.min != null) 
                        errors += " and less than " + e.max;
                    else if (e.max != null)
                        errors += " that is less than " + e.max;
                    errors += ".\n";
                }
            }
        }
		else if ((e.type == "checkbox")  && !e.optional) {
            // first check if the field is empty
            if (!e.checked) {
                errors += "\n" + "- You have not accepted the Terms and Conditions";
                continue;
            }
			//alert(e.name + " " + e.type);
		}
		else if ((e.type == "password")  && !e.optional) {
            // first check if the field is empty
            if ((e.value == null) || (e.value == "") || isblank(e.value)) {
                empty_fields += "\n          " + e.name;
                continue;
            }
			
			if ((e.value.length > pmax) || (e.value.length < pmin)) {
				errors += "\n" + "- Incorrect Password Length";
				continue;
			}
			if (e.name == "Password") init_pass = e.value;
			if (e.name == "Confirm Password") conf_pass = e.value;
			if ((init_pass != "") && (conf_pass != "")) {
				if (init_pass != conf_pass) {
					errors += "\n" + "- Passwords do not match";
					continue;
				}
			}
			//alert(e.name + " " + e.type);
		}
    }

    // Now, if there were any errors, display the messages, and
    // return false to prevent the form from being submitted. 
    // Otherwise return true.
    if (!empty_fields && !errors) return true;

    msg  = "______________________________________________________\n\n"
    msg += "The form was not submitted because of the following error(s).\n";
    msg += "Please correct these error(s) and re-submit.\n";
    msg += "______________________________________________________\n\n"

    if (empty_fields) {
        msg += "- The following required field(s) are empty or invalid:" 
                + empty_fields + "\n";
        if (errors) msg += "\n";
    }
    msg += errors;
    alert(msg);
    return false;
}