var whitespace = " \t\n\r";
var defaultEmptyOK = false

// m is an abbreviation for "missing"
var mPrefix = ""
var mSuffix = " is a required field. Please enter it now."


function checkBarcode(field){
   var s = "The barcode you entered is invalid. It should match the pattern 22101 123456789.  Please try again.";
   bcode = field.value;
   if (isWhitespace(bcode)) return warnEmpty (field, "Barcode");
   bcode = stripWhitespace(bcode);
   bcode = bcode.substr(5);
   if (bcode.length != 9) return warnInvalid(field, s);
   for (i = 0; i < 9; i++){   
     		var c = bcode.charAt(i);
   		if (!isDigit(c)) return warnInvalid(field, s);
   	}
   document.regForm.barcode.value = bcode;
   return true;
}

function checkRoom(list){
	if ( list.selectedIndex == 0) {
		list.focus();
		alert ("Please select a room from the list");
		return false;
	}
	else {return true;}
}

function checkSubmitter(form){
		if (form.elements["Submitter"].selectedIndex == 0){
			return (
				checkString(form.elements["lName"],"Last Name") &&
				checkString(form.elements["fName"],"First Name") &&
				checkString(form.elements["Phone"],"Campus Phone") &&
				checkString(form.elements["Email"],"E-mail Address")
			)
		}
		else return true;
}

function checkDate(field){
	str = field.value;
	re1 = /^\d{1,2}\/\d{1,2}(\/\d{2})$/;
	re2 = /^\d{1,2}\/\d{1,2}$/
 	if (re1.test(str) || re2.test(str)) return true;
	else return warnInvalid(field, "Enter the date in the form 3/5/01")
}

function checkTime(field){
	str = field.value;
	re1 = /^\d{1,2}\s[ap]m$/;
	re2 = /^\d{1,2}:\d{2}\s[ap]m$/;
	if (re1.test(str) || re2.test(str)) return true;
	else return warnInvalid(field, "Enter the time in the form 10 am or 3:30 pm")
}


function checkZero(theField, m){
			s = theField[theField.selectedIndex].value;
			t = theField[theField.selectedIndex].text;
			if ((s == null) || (s.length == 0) || (s == 0)){
				theField.focus();
				alert("Please select " + m);
				return false;
			}
			else return true;
		}
	
function isDigit (c)
{   return ((c >= "0") && (c <= "9"))
}


function isEmpty(s){
   return ((s == null) || (s.length == 0))
}
	
function isWhitespace (s){
   var i;

    // Is s empty?
    if (isEmpty(s)) return true;

    // Search through string's characters one by one
    // until we find a non-whitespace character.
    // When we do, return false; if we don't, return true.

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);

        if (whitespace.indexOf(c) == -1) return false;
    }

    // All characters are whitespace.
    return true;
}		
		
function stripWhitespace (s){
   return stripCharsInBag (s, whitespace)
}
	
// Removes all characters which appear in string bag from string s.

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++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }

    return returnString;
}
		
function warnEmpty (theField, s)
{   theField.focus()
    alert(mPrefix + s + mSuffix)
    return false
}


function warnInvalid (theField, s){
   theField.focus()
   theField.select()
   alert(s)
   return false
}



// checkString (TEXTFIELD theField, STRING s, [, BOOLEAN emptyOK==false])
//
// Check that string theField.value is not all whitespace.
//
// For explanation of optional argument emptyOK,
// see comments of function isInteger.

function checkString (theField, s, emptyOK)
{   // Next line is needed on NN3 to avoid "undefined is not a number" error
    // in equality comparison below.
    if (checkString.arguments.length == 2) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    if (isWhitespace(theField.value)) 
       return warnEmpty (theField, s);
    else return true;
}