function switchStageDatum(selfName, objName) {
	var obj = document.getElementById(objName);
	var check = document.getElementById(selfName);

	if (check.checked == true) {
		obj.style.display = 'block';
	} else {
		obj.style.display = 'none';
	}
		
}

function isLeapYear(datea) {
	datea = parseInt(datea);

	if(datea%4 == 0) {
		if(datea%100 != 0) {
			return true;
		} else {
			if(datea%400 == 0)
				return true;
			else
				return false;
		}
	}
	return false;
}

Array.prototype.inArray = function (value) {
	var i;
	for (i=0; i < this.length; i++) {
		if (this[i] === value) {
			return true;
		}
	}
	return false;
};		
	
function verifyMonth(objMonthId, objDaysId, objYearId) {

	var selectedMonth;
	var thirtyOneDayMonths;
	var dayDdl;
	var selectedYear;
    
	thirtyOneDayMonths = new Array('1','3','5','7','8','10','12');          
	selectedMonth = document.getElementById(objMonthId).value;
	selectedYear = document.getElementById(objYearId).value;
	dayDdl = document.getElementById(objDaysId);

	if (dayDdl.options.length<29) { dayDdl.options[28] = new Option(29,29); }
	if (dayDdl.options.length<30) { dayDdl.options[29] = new Option(30,30); }
	if (dayDdl.options.length<31) { dayDdl.options[30] = new Option(31,31); }
                
	if (!thirtyOneDayMonths.inArray(selectedMonth)) {
		if (selectedMonth==2) {
		dayDdl.options[30] = null;
		dayDdl.options[29] = null;
           
			if (isLeapYear(selectedYear)) {
				dayDdl.options[28] = null;
			}
		} else {
			if (dayDdl.options.length>30) { 
				dayDdl.options[30] = null;
			}
		}
	} else {
		if (dayDdl.options.length<31) {
			dayDdl.options[30] = new Option(31,31);
		}
	}
    
}

function switchTab(clickedTab) {
					
	resetTabs()
						
	document.getElementById('tab' + clickedTab + '_middle').className = 'middleBlue';													
	
	if (clickedTab>1) {
		document.getElementById('tab' + clickedTab + '_right').className = 'BlueGrey';
		document.getElementById('tab' + (clickedTab - 1) + '_right').className = 'GreyBlue';
	} else {
		document.getElementById('tab1_left').className = 'leftEdgeBlue';
	}
	
	if (clickedTab<3) {
		document.getElementById('tab' + clickedTab + '_right').className = 'BlueGrey';
	} else {
		document.getElementById('tab3_right').className = 'rightEdgeBlue';
	}
	
	document.getElementById('table' + clickedTab).style.display='block';
}

function resetTabs() {
	for (i=1;i<4;i++) {
		document.getElementById('tab' + i + '_middle').className = 'middleGrey';
		document.getElementById('tab' + i + '_right').className = 'GreyGrey';
		document.getElementById('table' + i).style.display='none';
	}
	document.getElementById('tab1_left').className = 'leftEdgeGrey';
	document.getElementById('tab3_right').className = 'rightEdgeGrey';
}