function getValue(theField)
{
	var theType
	theType = theField.type;

	if ( (theType == "hidden") || (theType == "password") || (theType == "select-one") || (theType == "text") || (theType == "textarea") || (theType == "select-multiple") )
		{
			return theField.value;
		}
	else //for "checkbox" and "radio" we just return the first value
		{
			if (theField.length >= 0)
				{
					for (var i=0; i<theField.length; i++) {
					  if (theField[i].checked)
					  {
						return theField[i].value;
					  }
					}
				}
			return "";
		}
	
}

function isblank(s)
{
for(var i=0;i<s.length;i++)
{
	var c = s.charAt(i);
	if ((c != ' ') && (c != '\n') && (c != '')) 
		{
			return false;
		}
}
return true;
}

function hasValue(fieldName,errorText)
{
	var theField, theValue;
	theField = MM_findObj(fieldName);
	if (theField != null)
	{
		theValue = getValue(theField);
		if ((theValue == null) || (theValue == '') || (isblank(theValue))) 
		{
			checkStr += '\n' + errorText;
			return false;
		}
	}
	else
	{
		checkStr += '\nOne of the expected questions in the survey could not be found. You may need to restart the survey'
		return false;
	}
	return true;
}

function isInNumberRange(fieldName,startValue,endValue,errorText)
{
	var theField, theValue;
	theField = MM_findObj(fieldName);
	if (theField != null)
	{
		theValue = getValue(theField);
		if (isNaN(theValue))
			{
				checkStr += '\n' + errorText;
				return false;
			}
		else
			{
				if (theValue.length > 0)
					{
						if (startValue.length > 0 && !isNaN(startValue) && theValue < startValue)
							{
								checkStr += '\n' + errorText;
								return false;
							}
						if (endValue.length > 0 && !isNaN(endValue) && theValue > endValue)
							{
								checkStr += '\n' + errorText;
								return false;
							}
					}
			}
	}
	else
	{
		checkStr += '\nOne of the expected questions in the survey could not be found. You may need to restart the survey'
		return false;
	}
	return true;
}

function isInDateRange(fieldName,startValue,endValue,errorText)
{
	var theField, theValue;
	theField = MM_findObj(fieldName);
	if (theField != null)
	{
		theValue = getValue(theField);
		if (theValue.length > 0)
		{
			if (!isDate(theValue))
			{
				checkStr += '\n' + errorText;
				return false;
			}
			else
			{
				if (    (startValue.length > 0 && isDate(startValue) && dateDiff(startValue,theValue) < 0)    ||   (endValue.length > 0 && isDate(endValue) && dateDiff(endValue,theValue) > 0) )
					{
						checkStr += '\n' + errorText;
						return false;
					}
			}
		}
	}
	else
	{
		checkStr += '\nOne of the expected questions in the survey could not be found. You may need to restart the survey'
		return false;
	}	
	return true;
}

function isEmail(fieldName,errorText)
{
	var theField, theValue;
	theField = MM_findObj(fieldName);
	if (theField != null)
	{
		theValue = getValue(theField);
		if (theValue.length > 0)
		{
			var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
			if (!filter.test(theValue))
				{
					checkStr += '\n' + errorText
					return false;
				}
		}
	}
	else
	{
		checkStr += '\nOne of the expected questions in the survey could not be found. You may need to restart the survey'
		return false;
	}
	return true;	
}

function isPostcode(fieldName,errorText)
{
	var theField, theValue;
	theField = MM_findObj(fieldName);
	if (theField != null)
	{
		theValue = getValue(theField);
		if (theValue.length > 0)
		{
			//var filter=/^[a-zA-Z]{2}\d{2}\s\d{1}[a-zA-Z]{2}$/
			var filter=/^([A-PR-UWYZ0-9][A-HK-Y0-9][AEHMNPRTVXY0-9]?[ABEHMNPRVWXY0-9]? {1,2}[0-9][ABD-HJLN-UW-Z]{2}|GIR 0AA)$/
			if (!filter.test(theValue))
				{
					checkStr += '\n' + errorText
					return false;
				}
		}
	}
	else
	{
		checkStr += '\nOne of the expected questions in the survey could not be found. You may need to restart the survey'
		return false;
	}
	return true;
}


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
}

function dateDiff(d1,d2)
{
var date1, date2, ms1, ms2;
date1 = new Date(d1);
date2 = new Date(d2);
ms1 = date1.getTime()
ms2 = date2.getTime()
if (ms2  > ms1) 
	{
		return 1
	}
if (ms2 < ms1) 
	{
		return -1
	}
	if (ms2 = ms1)
	{
		return 0
	}
//return Math.abs(date2.getTime() - date1.getTime());

}

function toggleDiv(divName)
{
  var theDiv;
  if (navigator.appName.indexOf('Microsoft') != -1) 
		{
		theDiv = MM_findObj(divName);
		if (theDiv != null)
			{
			var current = (theDiv.style.display == 'block') ? 'none' : 'block'
			theDiv.style.display = current;
			}
		}
}