//$Id: lib.js,v 1.11 2004/12/14 16:48:04 ed Exp $
//library of useful js functions

//trim string
function trimString (str) {
  str = this != window? this : str;
  return str.replace(/^\s+/g, '').replace(/\s+$/g, '');
}


var weouPop = null;
//all new star rewards popup window variable
var srPop = null;
var termsPop = null;
var weouPopScratch = null;

//open pop-up window
function openPop(winPop, winName, url, popWidth, popHeight, scrolling){
  
  if (scrolling === true) scrolling = 'yes';
  
  var details = "height=" + popHeight + ",width=" + popWidth + ",left=150,top=150,status=no,resizable=yes,titlebar=no,toolbar=no,location=no,scrollbars=" + scrolling + ",directories=no";

  if (winPop && winPop.open && !winPop.closed){
    winPop.resizeTo(popWidth, popHeight);				//only works in IE
    winPop.location = url;
    winPop.focus();
  }
  else { 
    winPop = window.open(url, winName, details);
    if(winPop) {winPop.focus();}
  }
  return winPop;
}


//close pop-up window
function closePop(winPop){
  if (winPop && winPop.open && !winPop.closed){
    winPop.close();
  }
}

/* for creating links from popup to main window */
function targetopener(mylink, closeme, closeonly)
{
	if (! (window.focus && window.opener))
		return true;
	window.opener.focus();
	if (! closeonly)
		window.opener.location.href = mylink.href;
	if (closeme)
		window.close();
	return false;
}

/*
Date Validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
*/

// Declare valid date character, minimum year and maximum year
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function isInteger(s)
{
	var i;
  for (i = 0; i < s.length; i++){   
      // Check that current character is number.
      var c = s.charAt(i);
      if (((c < "0") || (c > "9"))) return false;
  }
  // All characters are numbers.
  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++){   
      var c = s.charAt(i);
      if (bag.indexOf(c) == -1) returnString += c;
  }
  return returnString;
}

function daysInFebruary (year)
{
	// February has 29 days in any year evenly divisible by four,
  // EXCEPT for centurial years which are not also divisible by 400.
	return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}

function DaysArray(n) 
{
	for (var i = 1; i <= n; i++) {
		this[i] = 31;
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30;}
		if (i==2) {this[i] = 29;}
	} 
	return this;
}

function isDate(dtStr) 
{
	var daysInMonth = DaysArray(12);
	var pos1=dtStr.indexOf(dtCh);
	var pos2=dtStr.indexOf(dtCh,pos1+1);
	var strDay=dtStr.substring(0,pos1);
	var strMonth=dtStr.substring(pos1+1,pos2);
	var strYear=dtStr.substring(pos2+1);
	strYr=strYear;
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1);
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1);
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1);
	}
	month=parseInt(strMonth);
	day=parseInt(strDay);
	year=parseInt(strYr);
	if (pos1==-1 || pos2==-1){
		alert("The date format should be : dd/mm/yyyy");
		return false;
	}
	if (strMonth.length<1 || month<1 || month>12){
		alert("Please enter a valid month");
		return false;
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		alert("Please enter a valid day");
		return false;
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear);
		return false;
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		alert("Please enter a valid date");
		return false;
	}
	return true;
}


/* an array prototype function to return the key of a value if set */
function inArray(array, value)
{
  for (index in array)
	{
		if (array[index] == value) return index;
	}
  return false;
}



/* checks whether card number is valid */
function luhnCheck( CardNumber ) 
{
	if (isNaN(CardNumber)) 
	{
		return false;
	}

	var no_digit = CardNumber.length;
	var oddoeven = no_digit & 1;
	var sum = 0;

	for (var count = 0; count < no_digit; count++) 
	{
		var digit =	parseInt(CardNumber.charAt(count));
		if (!((count & 1) ^ oddoeven)) 
		{
			digit *= 2;
			if (digit > 9)
			{
				// very cleverly adds in one as well
				digit -= 9;
			}
		}
		sum += digit;
	}
	return (sum % 10 == 0);
}