// FormChek.js

// 18 Feb 97 created Eric Krock
//
// (c) 1997 Netscape Communications Corporation


// VARIABLE DECLARATIONS

var digits = "0123456789";

var lowercaseLetters = "abcdefghijklmnopqrstuvwxyz"

var uppercaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"


// whitespace characters
var whitespace = " \t\n\r";




// non-digit characters which are allowed in 
// Social Security Numbers
var SSNDelimiters = "- ";






// i is an abbreviation for "invalid"


var iEmail = "This field must be a valid email address (like user@bar.org). Please reenter it now."
var iCreditCardPrefix = "This is not a valid "
var iCreditCardSuffix = " credit card number. (Click the link on this form to see a list of sample numbers.) Please reenter it now."



// p is an abbreviation for "prompt"

var pEntryPrompt = "Please enter a "
var pStateCode = "2 character code (like CA)."
var pZIPCode = "5 or 9 digit U.S. ZIP Code (like 94043)."
var pUSPhone = "10 digit U.S. phone number (like 415 555 1212)."
var pWorldPhone = "international phone number."
var pSSN = "9 digit U.S. social security number (like 123 45 6789)."
var pEmail = "valid email address (like foo@bar.org)."




var defaultEmptyOK = false



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 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 stripCharsNotInBag (s, bag)

{   var i;
    var returnString = "";

    // Search through string's characters one by one.
    // If character is 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 stripWhitespace (s)

{   return stripCharsInBag (s, whitespace)
}




function charInString (c, s)
{   for (i = 0; i < s.length; i++)
    {   if (s.charAt(i) == c) return true;
    }
    return false
}



// Removes initial (leading) whitespace characters from s.
// Global variable whitespace (see above)
// defines which characters are considered whitespace.

function stripInitialWhitespace (s)

{   var i = 0;

    while ((i < s.length) && charInString (s.charAt(i), whitespace))
       i++;
    
    return s.substring (i, s.length);
}



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


function isDigit (c)
{   return ((c >= "0") && (c <= "9"))
}


function isEmail (s)
{   if (isEmpty(s)) 
       if (isEmail.arguments.length == 1) return defaultEmptyOK;
       else return (isEmail.arguments[1] == true);
   
    // is s whitespace?
    if (isWhitespace(s)) return false;
    
    // there must be >= 1 character before @, so we
    // start looking at character position 1 
    // (i.e. second character)
    var i = 1;
    var sLength = s.length;

    // look for @
    while ((i < sLength) && (s.charAt(i) != "@"))
    { i++
    }

    if ((i >= sLength) || (s.charAt(i) != "@")) return false;
    else i += 2;

    // look for .
    while ((i < sLength) && (s.charAt(i) != "."))
    { i++
    }

    // there must be at least one character after the .
    if ((i >= sLength - 1) || (s.charAt(i) != ".")) return false;
    else return true;
}

function warnEmpty (theField, s)
{   theField.focus()
    theField.select()
    alert("You did not enter a value into the " + s + " field. This is a required field. Please enter it now.")
    return false
}



function warnInvalid (theField, s)
{   
    theField.value="";
    theField.focus();
    theField.select();
    alert(s + " Not valid!");
    return false
}

function warnInvalid2 (theField, s)
{   
    theField.value="";
    theField.focus();
    theField.select();
    alert(s);
    return false
}


function checkStatus( theField, s)
{

 if (theField[0].checked||theField[1].checked)return true;
 else
 { 
      alert("Please choose the " +s+" field!");
      
      return false;
   }

    
}


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;
}

function checkNum (theField,s)
{
   if (isEmpty(theField.value)||theField.value.length<3) return warnInvalid (theField, s);
   
   for (i = 0; i < theField.value.length; i++)
    {   
    t = theField.value.charAt(i);
    if (!isDigit(t)) return warnInvalid (theField, s);
    }
    return true;
}

function checkNum2 (theField,s)
{

   if(isEmpty(theField.value)||theField.value.length<4) return warnInvalid (theField, s);
   
   for (i = 0; i < theField.value.length; i++)
    {   
    t = theField.value.charAt(i);
    if (!isDigit(t)) return warnInvalid (theField, s);
    }
    return true;
}




function checkEmail (theField, emptyOK)
{   if (checkEmail.arguments.length == 1) emptyOK = defaultEmptyOK;
    if ((emptyOK == true) && (isEmpty(theField.value))) return true;
    else if (!isEmail(theField.value, false)) 
       return warnInvalid2 (theField,"Email address is not valid!!");
    else return true;
}