//a collection of functions used to validate form input
//TODO - update style for consistency

function formOnError(form_object, input_object, object_value, error_message){
	alert(error_message);
    return false;	
}

function formHasValue(obj, obj_type){
    if (obj_type == "TEXT" || obj_type == "PASSWORD"){
    	if (obj.value.length == 0){
      		return false;
    	}else{
      		return true;
		}
    } else if (obj_type == "SELECT"){
        for (i=0; i < obj.length; i++){
			if (obj.options[i].selected){
				return true;
			}
		}
       	return false;	
	} else if (obj_type == "SINGLE_VALUE_RADIO" || obj_type == "SINGLE_VALUE_CHECKBOX"){
		if (obj.checked)
			return true;
		else
       		return false;	
	} else if (obj_type == "RADIO" || obj_type == "CHECKBOX"){
        for (i=0; i < obj.length; i++){
			if (obj[i].checked){
				return true;
			}
		}
       	return false;	
	}
}

function isLetter(c){
	return ( ((c >= "a") && (c <= "z")) || ((c >= "A") && (c <= "Z")) )
}

// Returns true if character c is a digit 
function isDigit (c){   
	return ((c >= "0") && (c <= "9"))
}

// Returns true if character c is a letter or digit.
function isLetterOrDigit (c){   
	return (isLetter(c) || isDigit(c))
}

function formCheckAlphanumeric(object_value){   
	var i;
	var validated = true;
    if (object_value.length < 1){
		return true;
	}
    // Search through string's characters one by one
    for (i = 0; i<object_value.length; i++){   
        // Check that current character is number or letter.
        c = object_value.charAt(i);
        if (!(isLetter(c) || isDigit(c) || (c == '_'))){//allows underscores as well
        	validated = false;
		}
    }
    return validated;
}


function formCheckDate(object_value)
    {
    //Returns true if value is a date format or is NULL
    //otherwise returns false	

    if (object_value.length == 0)
        return true;

    //Returns true if value is a date in the mm/dd/yyyy format
	isplit = object_value.indexOf('/');

	if (isplit == -1 || isplit == object_value.length)
		return false;

    sMonth = object_value.substring(0, isplit);

	if (sMonth.length == 0)
        return false;

	isplit = object_value.indexOf('/', isplit + 1);

	if (isplit == -1 || (isplit + 1 ) == object_value.length)
		return false;

    sDay = object_value.substring((sMonth.length + 1), isplit);

	if (sDay.length == 0)
        return false;

	sYear = object_value.substring(isplit + 1);

	if (!formCheckInteger(sMonth)) //check month
		return false;
	else
	if (!formCheckRange(sMonth, 1, 12)) //check month
		return false;
	else
	if (!formCheckInteger(sYear)) //check year
		return false;
	else
	if (!formCheckRange(sYear, 0, 9999)) //check year
		return false;
	else
	if (!formCheckInteger(sDay)) //check day
		return false;
	else
	if (!formCheckDay(sYear, sMonth, sDay)) // check day
		return false;
	else
		return true;
    }



function formCheckDay(checkYear, checkMonth, checkDay)
    {

	maxDay = 31;

	if (checkMonth == 4 || checkMonth == 6 ||
			checkMonth == 9 || checkMonth == 11)
		maxDay = 30;
	else
	if (checkMonth == 2)
	{
		if (checkYear % 4 > 0)
			maxDay =28;
		else
		if (checkYear % 100 == 0 && checkYear % 400 > 0)
			maxDay = 28;
		else
			maxDay = 29;
	}

	return formCheckRange(checkDay, 1, maxDay); //check day
    }



function formCheckInteger(object_value)
    {
    //Returns true if value is a number or is NULL
    //otherwise returns false	

    if (object_value.length == 0)
        return true;

    //Returns true if value is an integer defined as
    //   having an optional leading + or -.
    //   otherwise containing only the characters 0-9.
	var decimal_format = ".";
	var check_char;

    //The first character can be + -  blank or a digit.
	check_char = object_value.indexOf(decimal_format)
    //Was it a decimal?
    if (check_char < 1)
	return formCheckNumber(object_value);
    else
	return false;
}



function formCheckNumberRange(object_value, min_value, max_value)
    {
    // check minimum
    if (min_value != null)
	{
        if (object_value < min_value)
		return false;
	}

    // check maximum
    if (max_value != null)
	{
	if (object_value > max_value)
		return false;
	}
	
    //All tests passed, so...
    return true;
    }



function formCheckNumber(object_value)
    {
    //Returns true if value is a number or is NULL
    //otherwise returns false	

    if (object_value.length == 0)
        return true;

    //Returns true if value is a number defined as
    //   having an optional leading + or -.
    //   having at most 1 decimal point.
    //   otherwise containing only the characters 0-9.
	var start_format = " .+-0123456789";
	var number_format = " .0123456789";
	var check_char;
	var decimal = false;
	var trailing_blank = false;
	var digits = false;

    //The first character can be + - .  blank or a digit.
	check_char = start_format.indexOf(object_value.charAt(0))
    //Was it a decimal?
	if (check_char == 1)
	    decimal = true;
	else if (check_char < 1)
		return false;
        
	//Remaining characters can be only . or a digit, but only one decimal.
	for (var i = 1; i < object_value.length; i++)
	{
		check_char = number_format.indexOf(object_value.charAt(i))
		if (check_char < 0)
			return false;
		else if (check_char == 1)
		{
			if (decimal)		// Second decimal.
				return false;
			else
				decimal = true;
		}
		else if (check_char == 0)
		{
			if (decimal || digits)	
				trailing_blank = true;
        // ignore leading blanks

		}
	        else if (trailing_blank)
			return false;
		else
			digits = true;
	}	
    //All tests passed, so...
    return true
    }



function formCheckRange(object_value, min_value, max_value)
    {
    //if value is in range then return true else return false

    if (object_value.length == 0)
        return true;


    if (!formCheckNumber(object_value))
	{
	return false;
	}
    else
	{
	return (formCheckNumberRange((eval(object_value)), min_value, max_value));
	}
	
    //All tests passed, so...
    return true;
    }



function formCheckPhone(object_value)
    {
    if (object_value.length == 0)
        return true;
		
    if (object_value.length != 12)
        return false;

	// check if first 3 characters represent a valid area code
    if (!formCheckNumber(object_value.substring(0,3)))
		return false;
    else
	if (!formCheckNumberRange((eval(object_value.substring(0,3))), 100, 1000))
		return false;

	// check if area code/exchange separator is either a'-' or ' '
	if (object_value.charAt(3) != "-" && object_value.charAt(3) != " ")
        return false

	// check if  characters 5 - 7 represent a valid exchange
    if (!formCheckNumber(object_value.substring(4,7)))
		return false;
    else
	if (!formCheckNumberRange((eval(object_value.substring(4,7))), 100, 1000))
		return false;
	
	// check if exchange/number separator is either a'-' or ' '
	if (object_value.charAt(7) != "-" && object_value.charAt(7) != " ")
        return false;

	// make sure last for digits are a valid integer
	if (object_value.charAt(8) == "-" || object_value.charAt(8) == "+")
        return false;
	else
	{
		return (formCheckInteger(object_value.substring(8,12)));
	}
    }



function formCheckZip(object_value)
    {
    if (object_value.length == 0)
        return true;
		
    if (object_value.length != 5 && object_value.length != 10)
        return false;

	// make sure first 5 digits are a valid integer
	if (object_value.charAt(0) == "-" || object_value.charAt(0) == "+")
        return false;

	if (!formCheckInteger(object_value.substring(0,5)))
		return false;

	if (object_value.length == 5)
		return true;
	
	// make sure

	// check if separator is either a'-' or ' '
	if (object_value.charAt(5) != "-" && object_value.charAt(5) != " ")
        return false;

	// check if last 4 digits are a valid integer
	if (object_value.charAt(6) == "-" || object_value.charAt(6) == "+")
        return false;

	return (formCheckInteger(object_value.substring(6,10)));
    }



function formCheckCreditCard(object_value)
    {
	var white_space = " -";
	var creditcard_string="";
	var check_char;


    if (object_value.length == 0)
        return true;

	// squish out the white space
	for (var i = 0; i < object_value.length; i++)
	{
		check_char = white_space.indexOf(object_value.charAt(i))
		if (check_char < 0)
			creditcard_string += object_value.substring(i, (i + 1));
	}	

	// if all white space return error
    if (creditcard_string.length == 0)
        return false;
	 
	 	
	// make sure number is a valid integer
	if (creditcard_string.charAt(0) == "+")
        return false;

	if (!formCheckInteger(creditcard_string))
		return false;

    // now check mod10

	var doubledigit = creditcard_string.length % 2 == 1 ? false : true;
	var checkdigit = 0;
	var tempdigit;

	for (var i = 0; i < creditcard_string.length; i++)
	{
		tempdigit = eval(creditcard_string.charAt(i))

		if (doubledigit)
		{
			tempdigit *= 2;
			checkdigit += (tempdigit % 10);

			if ((tempdigit / 10) >= 1.0)
			{
				checkdigit++;
			}

			doubledigit = false;
		}
		else
		{
			checkdigit += tempdigit;
			doubledigit = true;
		}
	}	
	return (checkdigit % 10) == 0 ? true : false;

    }
	
	
function formCheckEmail(object_value){
	var Email, AtPos, DotPos, badCharArray, validated
	validated = true;
	badCharArray = '( ) < > [ ] , ; : \\ /'.split(' ');
	
  	Email = new String(object_value);
  	AtPos = Email.indexOf("@");
  	DotPos = Email.lastIndexOf(".");
	 
	//check for @ and .
  	if (AtPos < 1 || DotPos <= AtPos +1 || DotPos == Email.length -1){
    	 validated = false;
 	}
	
	//check for illegal characters
	for (i=0;i<badCharArray.length;i++){
		if (Email.indexOf(badCharArray[i]) != -1) {
			validated = false;
		}
	}
	
	if (Email.indexOf(' ') > -1 || Email.split('@').length-1 > 1) {
    	 validated = false;
 	}

	return validated;
 }
	
	
	function formCheckLength(object_value, object_length){
    	if (object_value.length == object_length){
      		return true;
		}
    	else {
      		return false;
		}
    }
	
	
//simple search and replace function for strings
function replaceString(searchString, findString, replaceWithString){
	var newString = searchString;
	while (newString.indexOf(findString) != -1){
		startPos = newString.indexOf(findString);
		endPos = findString.length + startPos;
		newString = newString.substr(0, (startPos)) + replaceWithString + newString.substr(endPos, newString.length);
	}
	return newString;
}

//removes dashes and spaces from credit card numbers
function formatCreditCart(theCardNumber){
	var parsedCardNumber = '';
	parsedCardNumber = replaceString(theCardNumber, '-', '')
	parsedCardNumber = replaceString(parsedCardNumber, ' ', '')
	return parsedCardNumber;
}
	
function formCheckCC(CC_Num,CC_Type) {
	//format the cc number to remove dashes and spaces
	CC_Num = formatCreditCart(CC_Num)
	var theError = "";
    var CCN_digits = "";
	
    for (var i = 0; i < CC_Num.length; i++) {
        if ((CC_Num.charAt(i) == "0") || (CC_Num.charAt(i) == "1") || (CC_Num.charAt(i) == "2") || (CC_Num.charAt(i) == "3") || (CC_Num.charAt(i) == "4") || (CC_Num.charAt(i) == "5") || (CC_Num.charAt(i) == "6") || (CC_Num.charAt(i) == "7") || (CC_Num.charAt(i) == "8") || (CC_Num.charAt(i) == "9")) {
             CCN_digits = CCN_digits + CC_Num.charAt(i);
        }
	}
	
    var validcard = false;
    var msgind = 0;
	
	// validate length and prefix values against the card type
    if (CC_Type.toLowerCase() == "american express") {
        if (CCN_digits.length == 15) {
            if ((CCN_digits.substring (0, 2) == "34") || (CCN_digits.substring (0, 2) == "37")) {
                validcard = true;
			} else {
                msgind = 1;
			}
		} else { 
            msgind = 2;
		}
    } else if (CC_Type.toLowerCase() == "discover") {
        if (CCN_digits.length == 16) {
            if (CCN_digits.substring (0, 4) == "6011") {
                validcard = true;
            } else {
                msgind = 1;
			}
        } else {
            msgind = 2;
		}
    } else if (CC_Type.toLowerCase() == "mastercard") {
        if (CCN_digits.length == 16){
            if ((CCN_digits.substring (0, 2) >= "51") && (CCN_digits.substring (0, 2) <= "55")) {
                validcard = true;
            } else {
                msgind = 1;
			}
        } else {
            msgind = 2;
		}
    } else if (CC_Type.toLowerCase() == "visa") {
        if ((CCN_digits.length == 16) || (CCN_digits.length ==13)) {
            if (CCN_digits.substring (0, 1) == "4") {
                validcard = true;
            } else {
                msgind = 1;
			}
        } else {
            msgind = 2;
		}
    } else {
    	if (!validcard){
        	if (msgind == 1) {
            	theError = 'The Card Number (' + CC_Num + ') and the Card Type (' + CC_Type + ') do not match.';
        	} else if (msgind == 2) {
            	theError =  'The Card Number (' + CC_Num + ') is not the right length for the Card Type (' + CC_Type + ').';
			}
		}
    }  
	
	
	
	//now we know if the card type matches the number
    if (!validcard) {
        return (validcard);
	}
	
    var CheckSum = 0;
    for (var x = 1; x <= CCN_digits.length; x++) {
        var CurrentDigit = CCN_digits.charAt(CCN_digits.length - x);
        if (x % 2 == 0) {
            var WorkDigit = CurrentDigit * 2;    
            if (WorkDigit > 9) { 
                CheckSum = CheckSum + (1 - 0);
                CheckSum = CheckSum + (WorkDigit % 10);
            } else {
                CheckSum = CheckSum + (WorkDigit - 0);
            }     
        } else {
            CheckSum = CheckSum + (CurrentDigit - 0);
        }
    }
    if (CheckSum % 10) { 
        validcard = false; 
        theError = "I'm sorry, the Credit Card Number format is not valid, please try again."; 
    }
	
    return (validcard); 
}