var nbsp = 160;		// non-breaking space char
var node_text = 3;	// DOM text node-type
var emptyString = /^\s*$/ ;
var global_valfield;	// retain valfield for timer thread

// --------------------------------------------
//                  trim
// Trim leading/trailing whitespace off string
// --------------------------------------------

function trim(str)
{
  return str.replace(/^\s+|\s+$/g, '');
}


// --------------------------------------------
//                  setfocus
// Delayed focus setting to get around IE bug
// --------------------------------------------

function setFocusDelayed()
{
  global_valfield.focus();
}

function setfocus(valfield)
{
  // save valfield in global variable so value retained when routine exits
  global_valfield = valfield;
  setTimeout( 'setFocusDelayed()', 100 );
}


// --------------------------------------------
//                  msg
// Display warn/error message in HTML element.
// commonCheck routine must have previously been called
// --------------------------------------------

function msg(fld,     // id of element to display message in
             msgtype, // class to give element ("warn" or "error")
             message) // string to display
{
  // setting an empty string can give problems if later set to a 
  // non-empty string, so ensure a space present. (For Mozilla and Opera one could 
  // simply use a space, but IE demands something more, like a non-breaking space.)
  var dispmessage;
  if (emptyString.test(message)) 
    dispmessage = String.fromCharCode(nbsp);    
  else  
    dispmessage = message;

  var elem = document.getElementById(fld);
  elem.firstChild.nodeValue = dispmessage;  
  
  elem.className = msgtype;   // set the CSS class to adjust appearance of message
}

// --------------------------------------------
//            commonCheck
// Common code for all validation routines to:
// (a) check for older / less-equipped browsers
// (b) check if empty fields are required
// Returns true (validation passed), 
//         false (validation failed) or 
//         proceed (don't know yet)
// --------------------------------------------

var proceed = 2;  

function commonCheck    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  if (!document.getElementById) 
    return true;  // not available on this browser - leave validation to the server
  var elem = document.getElementById(infofield);
  if (!elem.firstChild) return true;  // not available on this browser 
  if (elem.firstChild.nodeType != node_text) return true;  // infofield is wrong type of node  

  if (emptyString.test(valfield.value)) {
    if (required) {
      msg (infofield, "*", "* required");  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "*", "");   // OK
      return true;  
    }
  }
  return proceed;
}

// --------------------------------------------
//            validatePresent
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validatePresent(valfield,   // element to be validated
                         infofield ) // id of element to receive info/error msg
{
  var stat = commonCheck (valfield, infofield, true);
  if (stat != proceed) return stat;

  msg (infofield, "*", "");  
  return true;
}

// --------------------------------------------
//               validateEmail
// Validate if e-mail address
// Returns true if so (and also if could not be executed because of old browser)
// --------------------------------------------

function validateEmail  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);  // value of field with whitespace trimmed off
  var email = /^[^@]+@[^@.]+\.[^@]*\w\w$/  ;
  if (!email.test(tfld)) {
    msg (infofield, "error", "* not a valid e-mail address");
    setfocus(valfield);
    return false;
  }

  var email2 = /^[A-Za-z][\w.-]+@\w[\w.-]+\.[\w.-]*[A-Za-z][A-Za-z]$/  ;
  if (!email2.test(tfld)) 
    msg (infofield, "warn", "* unusual e-mail address - check if correct");
  else
    msg (infofield, "warn", "");
  return true;
}


// --------------------------------------------
//            validateTelnr
// Validate telephone number
// Returns true if so (and also if could not be executed because of old browser)
// Permits spaces, hyphens, and parenthesis
// --------------------------------------------

function validateTelnr  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);  // value of field with whitespace trimmed off
  var telnr = /^\+?[0-9 ()-]+[0-9]$/  ;
  if (!telnr.test(tfld)) {
    msg (infofield, "error", "* not a valid telephone number");
    setfocus(valfield);
    return false;
  }

  var numdigits = 0;
  for (var j=0; j<tfld.length; j++)
    if (tfld.charAt(j)>='0' && tfld.charAt(j)<='9') numdigits++;

  if (numdigits<6) {
    msg (infofield, "error", "* " + numdigits + " digits - too short");
    setfocus(valfield);
    return false;
  }

  if (numdigits>14)
    msg (infofield, "*", "* " + numdigits + " digits - check if correct");
  else { 
    if (numdigits<10)
      msg (infofield, "*", "* only " + numdigits + " digits - check if correct");
    else
      msg (infofield, "*", "");
  }
  return true;
}




// --------------------------------------------
//            validateCCnr
// Validate credit card number
// Returns true if so (and also if could not be executed because of old browser)
// --------------------------------------------

function validateCCnr  (valfield,   // element to be validated
                        infofield,  // id of element to receive info/error msg
                        required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

//*************
var ccNumb = valfield.value;
var valid = "0123456789"  // Valid digits in a credit card number
var len = ccNumb.length;  // The length of the submitted cc number
var iCCN = parseInt(ccNumb);  // integer of ccNumb
var sCCN = ccNumb.toString();  // string of ccNumb
sCCN = sCCN.replace (/^\s+|\s+$/g,'');  // strip spaces
var iTotal = 0;  // integer total set at zero
var bNum = true;  // by default assume it is a number
var bResult = false;  // by default assume it is NOT a valid cc
var temp;  // temp variable for parsing string
var calc;  // used for calculation of each digit

// Determine if the ccNumb is in fact all numbers
for (var j=0; j<len; j++) {
  temp = "" + sCCN.substring(j, j+1);
  if (valid.indexOf(temp) == "-1"){bNum = false;}
}

// if it is NOT a number, you can either alert to the fact, or just pass a failure
if(!bNum){
  /*alert("Not a Number");*/bResult = false;
  msg (infofield, "error", "* not a valid credit card");
  setfocus(valfield);
  return false;
}

// Determine if it is the proper length 
if((len == 0)&&(bResult)){  // nothing, field is blank AND passed above # check
  bResult = false;
  msg (infofield, "error", "* not a valid credit card");
  setfocus(valfield);
  return false;
} else{  // ccNumb is a number and the proper length - let's see if it is a valid card number
  if(len >= 15){  // 15 or 16 for Amex or V/MC
    for(var i=len;i>0;i--){  // LOOP throught the digits of the card
      calc = parseInt(iCCN) % 10;  // right most digit
      calc = parseInt(calc);  // assure it is an integer
      iTotal += calc;  // running total of the card number as we loop - Do Nothing to first digit
      i--;  // decrement the count - move to the next digit in the card
      iCCN = iCCN / 10;                               // subtracts right most digit from ccNumb
      calc = parseInt(iCCN) % 10 ;    // NEXT right most digit
      calc = calc *2;                                 // multiply the digit by two
      // Instead of some screwy method of converting 16 to a string and then parsing 1 and 6 and then adding them to make 7,
      // I use a simple switch statement to change the value of calc2 to 7 if 16 is the multiple.
      switch(calc){
        case 10: calc = 1; break;       //5*2=10 & 1+0 = 1
        case 12: calc = 3; break;       //6*2=12 & 1+2 = 3
        case 14: calc = 5; break;       //7*2=14 & 1+4 = 5
        case 16: calc = 7; break;       //8*2=16 & 1+6 = 7
        case 18: calc = 9; break;       //9*2=18 & 1+8 = 9
        default: calc = calc;           //4*2= 8 &   8 = 8  -same for all lower numbers
      }                                               
    iCCN = iCCN / 10;  // subtracts right most digit from ccNum
    iTotal += calc;  // running total of the card number as we loop
  }  // END OF LOOP
  
  if ((iTotal%10)==0){  // check to see if the sum Mod 10 is zero
    bResult = true;  // This IS (or could be) a valid credit card number.
  } else {
    bResult = false;
    msg (infofield, "error", "* not a valid credit card");
    setfocus(valfield);
    return false;  // This could NOT be a valid credit card number
    }
  }
}
// change alert to on-page display or other indication as needed.

  if(!bResult){
  msg (infofield, "error", "* not a valid credit card");
  setfocus(valfield);
  } else {
         msg (infofield, "*", "");   // OK
  }
  return bResult; // Return the results
}




            

// --------------------------------------------
//               validateExpiry
// Returns true if so (and also if could not be executed because of old browser)
// --------------------------------------------

function validateExpiry (infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var tfld = parseInt(document.payment_info.expire_month.options[document.payment_info.expire_month.selectedIndex].value);
  var tfld2 = parseInt(document.payment_info.expire_year.options[document.payment_info.expire_year.selectedIndex].value);
 
  var currentDate = new Date();
  
  var currentMonth = parseInt(currentDate.getMonth()+1);
  var currentYear = parseInt(currentDate.getFullYear());
  
  if (tfld2 == currentYear)
      {
        if (tfld < currentMonth){
            msg (infofield, "error", "* date cannot be prior to " + currentMonth + "/" + currentYear);
            return false;
       } else {
            msg (infofield, "*", "");   // OK
            return true;
       }
      
        
  } else {
        msg (infofield, "*", "");   // OK
        return true;
  }
  
  
}


// --------------------------------------------
//               validateChargeTotal
// --------------------------------------------
function validateChargeTotal(valfield,   // element to be validated
                            infofield,  // id of element to receive info/error msg
                            required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

   var strValidChars = "0123456789.-";
   var strChar;
   var blnResult = true;
   var strString = valfield.value
   
   if (strString.length == 0) return false;

   //  test strString consists of valid characters listed above
   for (i = 0; i < strString.length && blnResult == true; i++)
      {
      strChar = strString.charAt(i);
      if (strValidChars.indexOf(strChar) == -1)
         {
         blnResult = false;
         msg (infofield, "error", "* amount must be numeric");
         setfocus(valfield);
         return false;
 
         }
    }
    
    if (parseFloat(strString) > 0)
    {
        msg (infofield, "*", "");   // OK
        return true;
    } else {
        msg (infofield, "error", "* amount must be > $0.00");
        setfocus(valfield);
        return false;
    }
 
        
}