//* Environement variables (browsers)
var ns4 = (document.layers)? true:false;
var ie4 = (document.all)? true:false;
var ns6 = (document.getElementById)? true:false;

//* Utilities functions
function isDigit(num) {
  if (num.length > 1)
    return false;
  
  var string = new String("1234567890");
  if (string.indexOf(num) != -1)
    return true;
  
  return false;
}

function isStringNumeric(stringValue) {
  var valid = false;
  var stringValue = new String(stringValue);
  if (stringValue.match(/^\d+$/)) valid = true;
  return valid;
}

function isInteger(val) {
	for (var i=0;i<val.length;i++) {
	  if (!isDigit(val.charAt(i)))
      return false;
  }
	return true;
}

//*************************************************
//* Fields function
//*************************************************

//**************************************************************************
//* checkPhoneNumber(regCode, prefix, suffix)
//* 
//* returned errorCodes :
//* [regCode] : -1 = empty ; -2 = not numeric ; -3 = length<3
//* [prefix]  : -4 = empty ; -5 = not numeric ; -6 = length<3
//* [suffix]  : -7 = empty ; -8 = not numeric ; -9 = length<3
//**************************************************************************
function checkPhoneNumber(regCode, prefix, suffix) {
  var valid = true;
  
  if (regCode.length == 0)
    valid = -1;
  else if (!isStringNumeric(regCode))
    valid = -2;
  else if (regCode.length != 3)
    valid = -3;
  
  else if (prefix.length == 0)
    valid = -4;
  else if (!isStringNumeric(prefix))
    valid = -5;
  else if (prefix.length != 3)
    valid = -6;
  
  else if (suffix.length == 0)
    valid = -7;
  else if (!isStringNumeric(suffix))
    valid = -8;
  else if (suffix.length != 4)
    valid = -9;
  
  return valid;
}

//**************************************************************************
//* checkZipCode(zipCodePrefix, zipCodeSuffix, country)
//* 
//* returned errorCodes [ca/us] :
//* [prefix]  : -1 = empty
//* [suffix]  : -2 = empty
//* [prefix]  : -3 = invalid format (ca: h1h; us: 12345)
//* [suffix]  : -4 = invalid format (ca: 1h1; us: 1234)
//**************************************************************************
function checkZipCode(zipCodePrefix, zipCodeSuffix, country) {
  var valid = true;
  
  var reg_ca_prefix  = /([a-zA-Z]{1})([0-9]{1})([a-zA-Z]{1})/;
  var reg_ca_suffix  = /([0-9]{1})([a-zA-Z]{1})([0-9]{1})/;
  var reg_us_prefix  = /([0-9]{5})/;
  var reg_us_suffix  = /([0-9]{4})/;
  
  switch (country.toLowerCase()) {
    case "ca":  if (zipCodePrefix == "")      //* If prefix empty
                  valid = -1;
                else if (zipCodeSuffix == "") //* If suffix empty
                  valid = -2;
                else if (!reg_ca_prefix.test(zipCodePrefix))    //* Invalid format
                  valid = -3;
                else if (!reg_ca_suffix.test(zipCodeSuffix))    //* Invalid format
                  valid = -4;
                
                break;
    
    case "us":  if (zipCodePrefix == "")      //* If prefix empty
                  valid = -1;
                else if (zipCodeSuffix == "") //* If suffix empty
                  valid = -2;
                else if (!reg_us_prefix.test(zipCodePrefix))    //* Invalid format
                  valid = -3;
                else if (!reg_us_suffix.test(zipCodeSuffix))    //* Invalid format
                  valid = -4;
                
                break;
  }
  
  return valid;
}

function checkEmail(emailStr) {
	/* The following pattern is used to check if the entered e-mail address
	   fits the user@domain format.  It also is used to separate the username
	   from the domain. */
	var emailPat=/^(.+)@(.+)$/
	/* The following string represents the pattern for matching all special
	   characters.  We don't want to allow special characters in the address. 
	   These characters include ( ) < > @ , ; : \ " . [ ]    */
	var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
	/* The following string represents the range of characters allowed in a 
	   username or domainname.  It really states which chars aren't allowed. */
	var validChars="\[^\\s" + specialChars + "\]"
	/* The following pattern applies if the "user" is a quoted string (in
	   which case, there are no rules about which characters are allowed
	   and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
	   is a legal e-mail address. */
	var quotedUser="(\"[^\"]*\")"
	/* The following pattern applies for domains that are IP addresses,
	   rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
	   e-mail address. NOTE: The square brackets are required. */
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
	/* The following string represents an atom (basically a series of
	   non-special characters.) */
	var atom=validChars + '+'
	/* The following string represents one word in the typical username.
	   For example, in john.doe@somewhere.com, john and doe are words.
	   Basically, a word is either an atom or quoted string. */
	var word="(" + atom + "|" + quotedUser + ")"
	// The following pattern describes the structure of the user
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
	/* The following pattern describes the structure of a normal symbolic
	   domain, as opposed to ipDomainPat, shown above. */
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")


	/* Finally, let's start trying to figure out if the supplied address is
	   valid. */

	/* Begin with the coarse pattern to simply break up user@domain into
	   different pieces that are easy to analyze. */
	var matchArray=emailStr.match(emailPat)
	if (matchArray==null) {
	  /* Too many/few @'s or something; basically, this address doesn't
		 even fit the general mould of a valid e-mail address. */
		//alert("Email address seems incorrect (check @ and .'s)")
		return false
	}
	var user=matchArray[1]
	var domain=matchArray[2]

	// See if "user" is valid 
	if (user.match(userPat)==null) {
		// user is not valid
		//alert("The username doesn't seem to be valid.")
		return false
	}

	/* if the e-mail address is at an IP address (as opposed to a symbolic
	   host name) make sure the IP address is valid. */
	var IPArray=domain.match(ipDomainPat)
	if (IPArray!=null) {
		// this is an IP address
		  for (var i=1;i<=4;i++) {
			if (IPArray[i]>255) {
				//alert("Destination IP address is invalid!")
			return false
			}
		}
		return true
	}

	// Domain is symbolic name
	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
		//alert("The domain name doesn't seem to be valid.")
		return false
	}

	/* domain name seems valid, but now make sure that it ends in a
	   three-letter word (like com, edu, gov) or a two-letter word,
	   representing country (uk, nl), and that there's a hostname preceding 
	   the domain or country. */

	/* Now we need to break up the domain to get a count of how many atoms
	   it consists of. */
	var atomPat=new RegExp(atom,"g")
	var domArr=domain.match(atomPat)
	var len=domArr.length
	if (domArr[domArr.length-1].length<2 || 
		domArr[domArr.length-1].length>3) {
	   // the address must end in a two letter or three letter word.
	   //alert("The address must end in a three-letter domain, or two letter country.")
	   return false
	}

	// Make sure there's a host name preceding the domain.
	if (len<2) {
	   var errStr="This address is missing a hostname!"
	   //alert(errStr)
	   return false
	}

	// If we've gotten this far, everything's valid!
	return true;
}