// Form Validation Functions  v1.1.6
// http://www.dithered.com/javascript/form_validation/index.html
// code by Chris Nott (chris@NOSPAMdithered.com - remove NOSPAM)
// modified for colehaan.com


function checkFormSection(form, formFields, emailField, errorMessageElementId) {

   // required fields left blank
   var emptyElements = new Array();
   for (var i = 0; i < formFields.length; i++) {
      var formFieldElement = document.getElementById(formFields[i].id);
      if (formFieldElement != null) {
         if (formFieldElement.nodeName == 'INPUT' && formFieldElement.value == '') {
            emptyElements[emptyElements.length] = formFields[i];
         }
         else if (formFieldElement.nodeName == 'SELECT' && formFieldElement.selectedIndex < 1) {
            emptyElements[emptyElements.length] = formFields[i];
         }
         else {
            formFieldElement.style.color = '#666666';
         }
      }
   }
   
   // non-blank fields with incorrectly formed values
   var badElements = new Array();
   if (emailField != null) {
      var formField = document.getElementById(emailField.id)
      if (isValidEmailStrict(formField.value) != true) {
         badElements[badElements.length] = emailField;
      }
   }
   
   // show error messages
   if (emptyElements.length > 0 || badElements.length > 0) {
      var errorMessages = '';
      var errorMessageHolder = document.getElementById(errorMessageElementId);
      
      for (var i = 0; i < emptyElements.length; i++) {
         var element = emptyElements[i];
         document.getElementById(element.id).style.color = '#ff0000';
         errorMessages += '*&nbsp;The ' + element.name + ' field is not filled in<br />';
      }
      
      for (var i = 0; i < badElements.length; i++) {
         var element = badElements[i];
         document.getElementById(element.id).style.color = '#ff0000';
         errorMessages += '*&nbsp;The ' + element.name + ' field value is not valid<br />';
      }
            
      errorMessageHolder.innerHTML = errorMessages;
      return false;
   }
   else {
      return true;
   }
}

// Check that the number of characters in a string is between a max and a min
function isValidLength(string, min, max) {
	if (string.length < min || string.length > max) return false;
	else return true;
}

//Check if password is a valid length.
function isValidPasswordLength(password){
	var passwordMinLength = 6;
	return password != undefined && trimWhitespace(password).length >= passwordMinLength;
}

// Check that a credit card number is valid based using the LUHN formula (mod10 is 0)
function isValidCreditCard(number) {
	number = '' + number;
	
	if (number.length > 16 || number.length < 13 ) return false;
	else if (getMod10(number) != 0) return false;
	else if (arguments[1]) {
		var type = arguments[1];
		var first2digits = number.substring(0, 2);
		var first4digits = number.substring(0, 4);
		
		if (type.toLowerCase() == 'visa' && number.substring(0, 1) == 4 &&
			(number.length == 16 || number.length == 13 )) return true;
		else if (type.toLowerCase() == 'mastercard' && number.length == 16 &&
			(first2digits == '51' || first2digits == '52' || first2digits == '53' || first2digits == '54' || first2digits == '55')) return true;
		else if (type.toLowerCase() == 'american express' && number.length == 15 && 
			(first2digits == '34' || first2digits == '37')) return true;
		else if (type.toLowerCase() == 'diners club' && number.length == 14 && 
			(first2digits == '30' || first2digits == '36' || first2digits == '38')) return true;
		else if (type.toLowerCase() == 'discover' && number.length == 16 && first4digits == '6011') return true;
		else if (type.toLowerCase() == 'enroute' && number.length == 15 && 
			(first4digits == '2014' || first4digits == '2149')) return true;
		else if (type.toLowerCase() == 'jcb' && number.length == 16 &&
			(first4digits == '3088' || first4digits == '3096' || first4digits == '3112' || first4digits == '3158' || first4digits == '3337' || first4digits == '3528')) return true;
		
    // if the above card types are all the ones that the site accepts, change the line below to 'else return false'
    else return true;
	}
	else return true;
}

// Check that an email address is valid based on RFC 821 (?)
function isValidEmail(address) {
	if (address != '' && address.search) {
      if (address.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1) return true;
      else return false;
	}
	
   // allow empty strings to return true - screen these with either a 'required' test or a 'length' test
   else return true;
}

// Check that an email address has the form something@something.something
// This is a stricter standard than RFC 821 (?) which allows addresses like postmaster@localhost
function isValidEmailStrict(address) {
	if (isValidEmail(address) == false) return false;
	var domain = address.substring(address.indexOf('@') + 1);
	if (domain.indexOf('.') == -1) return false;
	if (domain.indexOf('.') == 0 || domain.indexOf('.') == domain.length - 1) return false;
	return true;
}

// Check that a US zip code is valid
function isValidZipcode(zipcode) {
	zipcode = removeSpaces(zipcode);
	if (!(zipcode.length == 5 || zipcode.length == 9 || zipcode.length == 10)) return false;
   if ((zipcode.length == 5 || zipcode.length == 9) && !isNumeric(zipcode)) return false;
   if (zipcode.length == 10 && zipcode.search && zipcode.search(/^\d{5}-\d{4}$/) == -1) return false;
   return true;
}

// Check that a Canadian postal code is valid
function isValidPostalcode(postalcode) {
	if (postalcode.search) {
		postalcode = removeSpaces(postalcode);
		if (postalcode.length == 6 && postalcode.search(/^[a-zA-Z]\d[a-zA-Z]\d[a-zA-Z]\d$/) != -1) return true;
		else if (postalcode.length == 7 && postalcode.search(/^[a-zA-Z]\d[a-zA-Z]-\d[a-zA-Z]\d$/) != -1) return true;
		else return false;
	}
	return true;
}

// Check that a US or Canadian phone number is valid
function isValidUSPhoneNumber(areaCode, prefixNumber, suffixNumber) {
   if (arguments.length == 1) {
      var phoneNumber = arguments[0];
      phoneNumber = phoneNumber.replace(/\D+/g, '');
      var length = phoneNumber.length;
      if (phoneNumber.length >= 7) {
         var areaCode = phoneNumber.substring(0, length-7);
         var prefixNumber = phoneNumber.substring(length-7, length-4);
         var suffixNumber = phoneNumber.substring(length-4);
      }
      else return false;
   }
   else if (arguments.length == 3) {
      var areaCode = arguments[0];
      var prefixNumber = arguments[1];
      var suffixNumber = arguments[2];
   }
   else return true;

   if (areaCode.length != 3 || !isNumeric(areaCode) || prefixNumber.length != 3 || !isNumeric(prefixNumber) || suffixNumber.length != 4 || !isNumeric(suffixNumber)) return false;
   return true;
}

// Check that a string contains only letters and numbers
function isAlphanumeric(string, ignoreWhiteSpace) {
	if (string.search) {
		if ((ignoreWhiteSpace && string.search(/[^\w\s]/) != -1) || (!ignoreWhiteSpace && string.search(/\W/) != -1)) return false;
	}
	return true;
}

// Check that a string contains only letters
function isAlphabetic(string, ignoreWhiteSpace) {
	if (string.search) {
		if ((ignoreWhiteSpace && string.search(/[^a-zA-Z\s]/) != -1) || (!ignoreWhiteSpace && string.search(/[^a-zA-Z]/) != -1)) return false;
	}
	return true;
}

// Check that a string contains only numbers
function isNumeric(string, ignoreWhiteSpace) {
	if (string.search) {
		if ((ignoreWhiteSpace && string.search(/[^\d\s]/) != -1) || (!ignoreWhiteSpace && string.search(/\D/) != -1)) return false;
	}
	return true;
}

// Remove characters that might cause security problems from a string 
function removeBadCharacters(string) {
	if (string.replace) {
		string.replace(/[<>\"\'%;\)\(&\+]/, '');
	}
	return string;
}

// Remove all spaces from a string
function removeSpaces(string) {
	var newString = '';
	for (var i = 0; i < string.length; i++) {
		if (string.charAt(i) != ' ') newString += string.charAt(i);
	}
	return newString;
}

// Remove leading and trailing whitespace from a string
function trimWhitespace(string) {
	var newString  = '';
	var substring  = '';
	beginningFound = false;
	
	// copy characters over to a new string
	// retain whitespace characters if they are between other characters
	for (var i = 0; i < string.length; i++) {
		
		// copy non-whitespace characters
		if (string.charAt(i) != ' ' && string.charCodeAt(i) != 9) {
			
			// if the temporary string contains some whitespace characters, copy them first
			if (substring != '') {
				newString += substring;
				substring = '';
			}
			newString += string.charAt(i);
			if (beginningFound == false) beginningFound = true;
		}
		
		// hold whitespace characters in a temporary string if they follow a non-whitespace character
		else if (beginningFound == true) substring += string.charAt(i);
	}
	return newString;
}

// Returns a checksum digit for a number using mod 10
function getMod10(number) {
	
	// convert number to a string and check that it contains only digits
	// return -1 for illegal input
	number = '' + number;
	number = removeSpaces(number);
	if (!isNumeric(number)) return -1;
	
	// calculate checksum using mod10
	var checksum = 0;
	for (var i = number.length - 1; i >= 0; i--) {
		var isOdd = ((number.length - i) % 2 != 0) ? true : false;
		digit = number.charAt(i);
		
		if (isOdd) checksum += parseInt(digit);
		else {
			var evenDigit = parseInt(digit) * 2;
			if (evenDigit >= 10) checksum += 1 + (evenDigit - 10);
			else checksum += evenDigit;
		}
	}
	return (checksum % 10);
}