/*
	Global javascript functions

	
		boolean isColor(colorInput)
		boolean isInteger(intInput)
		boolena isNumeric(numInput)
		boolean isDate(dateInput)
		
		
		void	attributeDiagnostic(HTMLelement) // handy in development

*/

function isColor(colorInput) {
	// we expect six hexadecimal characters
	regExpObj = /([0-9]|[A-F]){6}/
	return regExpObj.test(colorInput.toUpperCase());
}


/**
 * DHTML date validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/)
 *
 * Modified 12/20/2003 by John Larson to allow MM/DD and MM/DD/YY format in addition to
 * MM/DD/YYYY already implemented.
 */
// Declaring 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 isNumeric(sText) {
   var ValidChars = "0123456789";
   var decimalSeen = false;
   var IsNumber=true;
   var Char;

//	 alert("Checking numeric validity...");

   for (i = 0; i < sText.length && IsNumber; i++) {
      Char = sText.charAt(i);
//		  alert("Examining character " + i + ": " + Char);
      if (Char == '-') {
      	 if (i != 0) {
    	  	 IsNumber = false;     // only a leading negative sign is allowed
    	 }
      }
      else if (Char == '.') {
      	 if (decimalSeen)
      	    IsNumber = false;  // can't have two decimals!
      	 else
      	 	decimalSeen = true;
      }
      else if (ValidChars.indexOf(Char) == -1) {
         IsNumber = false;
      }
   }
   return IsNumber;
}

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 extractCharsInBag(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++){   
        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 strMonth=dtStr.substring(0,pos1)
	var strDay=dtStr.substring(pos1+1,pos2)
	var strYear=dtStr.substring(pos2+1)

	var strTodaysYear = new String(new Date().getFullYear());
	if (pos2 < 0) // no year given, so assume this year
		strYr = strTodaysYear;
	else if (strYear.length == 2) // assume only last two digits given, so append first two
		strYr = strTodaysYear.substring(0, 2) + strYear;
	else if (strYear.length == 4) // standard format.
		strYr=strYear
	else
		return false;  // bad year

	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){
		//alert("The date format should be : mm/dd/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 (year<minYear || year>maxYear){
		//alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false
	}
	if (!isInteger(stripCharsInBag(dtStr, dtCh))) {
		alert("Please enter a valid date")
		return false
	}
return true
}



function attributeDiagnostic(element)
{
	var attributes = element.attributes;
	var i = 0;
	var display = ""
	for (var item in attributes) {
		display = display + item + ": " + element.getAttribute(item) + "\n";
		
		i++;
		
		if (i >= 35) { // clear out to make room
			alert("Attributes:\n" + display);
			display = ""
			i = 0;
		}
	}
		
	if (display != "")
		alert("Attributes:\n" + display);
}