// JavaScript Document

/**
 * DHTML date validation script. Courtesy of SmartWebby.com (http://www.smartwebby.com/dhtml/) mm/dd/yyyy
 */
// 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 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(day_select_id, month_select_id, year_select_id){
	
	day = document.getElementById(day_select_id).options[document.getElementById(day_select_id).selectedIndex].value;
	month = document.getElementById(month_select_id).options[document.getElementById(month_select_id).selectedIndex].value;
	year = document.getElementById(year_select_id).options[document.getElementById(year_select_id).selectedIndex].value;
	
	dtStr = month + "/" + day + "/" + year;
	
	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)
	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 : 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 in " + document.getElementById(year_select_id).title)
		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 replaceCarriageReturn(string,text,by) {
// Replaces text with by in string
	var strLength = string.length, txtLength = text.length;
	if ((strLength == 0) || (txtLength == 0)) return string;

	var i = string.indexOf(text);
	if ((!i) && (text != string.substring(0,txtLength))) return string;
	if (i == -1) return string;

	var newstr = string.substring(0,i) + by;

	if (i+txtLength < strLength)
		newstr += replaceCarriageReturn(string.substring(i+txtLength,strLength),text,by);

	return newstr;
}

function format(id)
{
	var trn_object = document.getElementById(id);
	formatted_string = "";
	raw_string = replaceCarriageReturn(trn_object.value,'-','');
	hyphen_count = 0;
	for(i = 0, count = 1; i < raw_string.length; i++, count++ )
	{
		formatted_string += raw_string.charAt(i);
		
		if(count != 0 && ((count % 3) == 0 && hyphen_count <= 2))
		{
			if(formatted_string.lastIndexOf('-') < 7)
			   formatted_string += '-';
			hyphen_count++;
		}
	}		
	trn_object.value = formatted_string;
}