function calcsurcharge(req) {
	//var form = document.taxcalc;
	form.surcharge.value = req.responseText;
	//alert("amit");
	
	}

	function calctax() {
		var form = document.taxcalc;

		form.surcharge.value='';
		
		//calculate net income
		form.net_income.value = +form.taxable_salary.value + +form.taxable_hra.value + +form.taxable_allowance.value + +form.taxable_education.value + +form.taxable_children.value - +form.prof_tax.value - +form.ent_allowance.value;
		if(form.net_income.value < 0) form.net_income.value = 0;
		//calculate house interest
		form.house_loss.value = +form.house_interest.value;

		//calculate gross income
		form.gross_income.value = (+form.net_income.value - +form.house_loss.value) + +form.other_income.value;
		if(form.gross_income.value < 0) form.gross_income.value = 0;
		//calculate total deducation
		form.total_deduction.value = +form.investments.value + +form.medical.value + +form.other_deduction.value;

		//calculate taxable income
		form.taxable_income.value = +form.gross_income.value - +form.total_deduction.value;
		if(form.taxable_income.value < 0) form.taxable_income.value = 0;

		var url = 'taxcalc.php?action=taxcalc' + '&category=' + form.category.value + '&net_income=' + form.net_income.value + '&house_loss=' + form.house_loss.value + '&other_income=' + form.other_income.value + '&gross_income=' + form.gross_income.value + '&total_deduction=' + form.total_deduction.value + '&taxable_income=' + form.taxable_income.value + '&income_tax=' + form.income_tax.value + '&surcharge=' + form.surcharge.value + '&edu_cess=' + form.edu_cess.value + '&add_edu_cess=' + form.add_edu_cess.value + '&total_tax=' + form.total_tax.value;
		
		ajaxpagefetcher.load('taxcalc', 'income_tax', url, true)

	}

	function surcharge() {

		var url = 'taxcalc.php?action=surcharge' + '&income_tax=' + form.income_tax.value + '&taxable_income=' + form.taxable_income.value + '&category=' + form.category.value;

		alert(url);
		
		ajaxpagefetcher.load('taxcalc', 'surcharge', url, true)
	}








	function showform()
	{

		var box = document.taxcalc.taxtype;
		var sallayer = document.getElementById('salariedlayer');
		var catlayer = document.getElementById('categorylayer');
		var inclayer = document.getElementById('incometext');

		if(box.options[box.selectedIndex].value=='Salaried')
		{
		sallayer.style.display = "block";
		catlayer.style.display = "block";
		inclayer.innerHTML = "Enter your Yearly Salary";
		}
		if(box.options[box.selectedIndex].value=='Self Employed')
		{
		sallayer.style.display = "none";
		catlayer.style.display = "block";
		inclayer.innerHTML = "Enter your Gross Income";
		}
		if(box.options[box.selectedIndex].value=='HUF')
		{
		sallayer.style.display = "none";
		catlayer.style.display = "none";
		inclayer.innerHTML = "Enter your Gross Income";
		}

		clearform();
	}

	function clearform()
	{
		var form = document.taxcalc;

		form.taxable_salary.value = 0;
		form.hra_recd.value= 0;
		form.rent_paid.value=0;
		form.metro.checked = false;
		form.conveyance.value = 0;
		form.education.value = 0;
		form.children.value = 0;
		form.lta.value = 0;
		form.medical.value = 0;
		form.telephone.value = 0;
		form.other_income.value = 0;
		$('ITText').innerHTML = '0';
	}

	function numOrdA(a, b){ return (a-b); }
	function numOrdD(a, b){ return (b-a); }


	function calchra() {

		var form = document.hracalc;

		//form.monthly_hra_recd.value = "10000";

		if(form.yearly_hra_recd.value != '' && form.yearly_rent_paid.value != '' && form.yearly_salary.value != '')
		{

		var hra = +form.yearly_rent_paid.value - +(form.yearly_salary.value*.10);

		var hra_paid = form.yearly_rent_paid.value;

		var hra_recd = form.yearly_hra_recd.value;
		

		if(form.yearlymetro.checked)
		{
			form.yearlymetro.value = 1;
		var fifty_salary = (form.yearly_salary.value)*.50;
		}
		else
		{
			form.yearlymetro.value = 0;
		var fifty_salary = (form.yearly_salary.value)*.40;
		}

		//var numArray = new Array(hra, hra_paid, fifty_salary);
		//numArray.sort( numOrdD );
	//	var taxfree_hra = numArray[0];

		if((form.yearly_salary.value*.10) < hra_paid)
		{
		var taxfree_hra = Math.min(hra, hra_recd, fifty_salary);
		}
		else
		{
		var taxfree_hra = 0;
		}
		//alert(hra_recd);
		var taxable_hra = +form.yearly_hra_recd.value - +taxfree_hra;


		form.yearly_taxfree_hra.value = taxfree_hra;
		form.yearly_taxable_hra.value = taxable_hra;

		//var url = "hracalc.php?action=hracalc&rangeopt=" + form.rangeopt.options[form.rangeopt.selectedIndex].value + "&yearly_hra_recd=" + form.yearly_hra_recd.value + "&yearly_rent_paid=" + form.yearly_rent_paid.value + "&yearlymetro=" + form.yearlymetro.value + "&yearly_salary=" + form.yearly_salary.value + "&yearly_taxfree_hra=" + form.yearly_taxfree_hra.value + "&yearly_taxable_hra=" + form.yearly_taxable_hra.value + "&fff=";

		//alert(url);

		//ajaxpagefetcher.load("taxcalc", "taxable_hra", url, true)

		document.taxcalc.taxable_hra.value = form.yearly_taxable_hra.value;
		}
	}

	function calcmonthlyhra(month)
	{
		//alert(month);
		var form = document.hracalc;
		var mhra_recd = month + "_hra_recd";
		var mrent_paid = month + "_rent_paid";
		var metro = month + "metro";
		var msalary = month + "_salary";
		var mtaxfree_hra = month + "_taxfree_hra";
		var mtaxable_hra = month + "_taxable_hra";

		
		if(form[mhra_recd].value >0 && form[mrent_paid].value>0 && form[msalary].value >0)
		{
		
		var hra = +form[mrent_paid].value - +(form[msalary].value*.10);

		var hra_paid = form[mrent_paid].value;

		var hra_recd = form[mhra_recd].value;
		

		if(form[metro].checked)
		{
			form[metro].value = 1;
		var fifty_salary = (form[msalary].value)*.50;
		}
		else
		{
			form[metro].value = 0;
		var fifty_salary = (form[msalary].value)*.40;
		}

		//var numArray = new Array(hra, hra_paid, fifty_salary);
		//numArray.sort( numOrdD );
	//	var taxfree_hra = numArray[0];

		if((form[msalary].value*.10) < hra_paid)
		{
		var taxfree_hra = Math.min(hra, hra_recd, fifty_salary);
		}
		else
		{
		var taxfree_hra = 0;
		}
		//alert("amit");
		var taxable_hra = +form[mhra_recd].value - taxfree_hra;
		
		
		form[mtaxfree_hra].value = taxfree_hra;
		form[mtaxable_hra].value = taxable_hra;

		//var url = "hracalc.php?action=hracalc&rangeopt=" + form.rangeopt.options[form.rangeopt.selectedIndex].value + "&monthly_hra_recd=" + form.monthly_hra_recd.value + "&monthly_rent_paid=" + form.monthly_rent_paid.value + "&monthlymetro=" + form.monthlymetro.value + "&monthly_salary=" + form.monthly_salary.value + "&monthly_taxfree_hra=" + form.monthly_taxfree_hra.value + "&monthly_taxable_hra=" + form.monthly_taxable_hra.value + "&fff=";

		//alert(url);

		//ajaxpagefetcher.load("hracalc","monthly_taxable_hra", url, true)
		}

		form.monthly_hra_recd.value = +form.apr_hra_recd.value + +form.may_hra_recd.value + +form.jun_hra_recd.value + +form.jul_hra_recd.value + +form.aug_hra_recd.value + +form.sept_hra_recd.value + +form.oct_hra_recd.value + +form.nov_hra_recd.value + +form.dec_hra_recd.value + +form.jan_hra_recd.value + +form.feb_hra_recd.value + +form.mar_hra_recd.value;


		form.monthly_rent_paid.value = +form.apr_rent_paid.value + +form.may_rent_paid.value + 				+form.jun_rent_paid.value + +form.jul_rent_paid.value + +form.aug_rent_paid.value + +form.sept_rent_paid.value + +form.oct_rent_paid.value + +form.nov_rent_paid.value + +form.dec_rent_paid.value + +form.jan_rent_paid.value + +form.feb_rent_paid.value + +form.mar_rent_paid.value;

		form.monthly_salary.value = +form.apr_salary.value + +form.may_salary.value + 				+form.jun_salary.value + +form.jul_salary.value + +form.aug_salary.value + +form.sept_salary.value + +form.oct_salary.value + +form.nov_salary.value + +form.dec_salary.value + +form.jan_salary.value + +form.feb_salary.value + +form.mar_salary.value;

		form.monthly_taxfree_hra.value = +form.apr_taxfree_hra.value + +form.may_taxfree_hra.value + 				+form.jun_taxfree_hra.value + +form.jul_taxfree_hra.value + +form.aug_taxfree_hra.value + +form.sept_taxfree_hra.value + +form.oct_taxfree_hra.value + +form.nov_taxfree_hra.value + +form.dec_taxfree_hra.value + +form.jan_taxfree_hra.value + +form.feb_taxfree_hra.value + +form.mar_taxfree_hra.value;

		form.monthly_taxable_hra.value = +form.apr_taxable_hra.value + +form.may_taxable_hra.value + 				+form.jun_taxable_hra.value + +form.jul_taxable_hra.value + +form.aug_taxable_hra.value + +form.sept_taxable_hra.value + +form.oct_taxable_hra.value + +form.nov_taxable_hra.value + +form.dec_taxable_hra.value + +form.jan_taxable_hra.value + +form.feb_taxable_hra.value + +form.mar_taxable_hra.value;

		document.taxcalc.taxable_hra.value = +form.monthly_taxable_hra.value;

	}


function calcconv()
{
	var form = document.convcalc;

	var yearly_conv = +form.yearly_conv_recd.value;

	if(yearly_conv <= 9600 )
	{
		form.yearly_taxfree_conv.value = yearly_conv;
		form.yearly_taxable_conv.value = 0;
	}
	else
	{
		form.yearly_taxfree_conv.value = 9600;
		form.yearly_taxable_conv.value = +yearly_conv - 9600;
	}

	document.taxcalc.taxable_allowance.value = +form.yearly_taxable_conv.value;
	calctax();
}

function calcmonthlyconv(month)
	{
		//alert(month);
		var form = document.convcalc;
		var mconv_recd = month + "_conv_recd";
		var mtaxfree_conv = month + "_taxfree_conv";
		var mtaxable_conv = month + "_taxable_conv";

		var monthly_conv_limit = 800;

		if(form[mconv_recd].value <= 800)
		{
			form[mtaxfree_conv].value = form[mconv_recd].value;
			form[mtaxable_conv].value = 0;
		}
		else
		{
			form[mtaxfree_conv].value = 800;
			form[mtaxable_conv].value = +form[mconv_recd].value - 800;
		}
		
		

		form.monthly_conv_recd.value = +form.apr_conv_recd.value + +form.may_conv_recd.value + +form.jun_conv_recd.value + +form.jul_conv_recd.value + +form.aug_conv_recd.value + +form.sept_conv_recd.value + +form.oct_conv_recd.value + +form.nov_conv_recd.value + +form.dec_conv_recd.value + +form.jan_conv_recd.value + +form.feb_conv_recd.value + +form.mar_conv_recd.value;

		form.monthly_taxfree_conv.value = +form.apr_taxfree_conv.value + +form.may_taxfree_conv.value + 				+form.jun_taxfree_conv.value + +form.jul_taxfree_conv.value + +form.aug_taxfree_conv.value + +form.sept_taxfree_conv.value + +form.oct_taxfree_conv.value + +form.nov_taxfree_conv.value + +form.dec_taxfree_conv.value + +form.jan_taxfree_conv.value + +form.feb_taxfree_conv.value + +form.mar_taxfree_conv.value;

		form.monthly_taxable_conv.value = +form.apr_taxable_conv.value + +form.may_taxable_conv.value + 				+form.jun_taxable_conv.value + +form.jul_taxable_conv.value + +form.aug_taxable_conv.value + +form.sept_taxable_conv.value + +form.oct_taxable_conv.value + +form.nov_taxable_conv.value + +form.dec_taxable_conv.value + +form.jan_taxable_conv.value + +form.feb_taxable_conv.value + +form.mar_taxable_conv.value;

		document.taxcalc.taxable_allowance.value = +form.monthly_taxable_conv.value;

		calctax();

	}


function showconv(elename)
	{

		var box = document.convcalc.rangeopt;
		var month = document.getElementById('convmonth');
		var year = document.getElementById('convyear');
		if(box.options[box.selectedIndex].value=='yearly')
		{
		year.style.display = "block";
		month.style.display = "none";
		}
		else
		{
		year.style.display = "none";
		month.style.display = "block";
		}
	}

	function showedu(elename)
	{

		var box = document.educalc.rangeopt;
		var month = document.getElementById('edumonth');
		var year = document.getElementById('eduyear');
		if(box.options[box.selectedIndex].value=='yearly')
		{
		year.style.display = "block";
		month.style.display = "none";
		}
		else
		{
		year.style.display = "none";
		month.style.display = "block";
		}
	}

	function calcedu()
	{
		var form = document.educalc;

		var childedu = 1200;

		if(form.yearly_edu_recd.value <= 2400 && form.yearly_edu_recd.value > 0)
		{
			if(form.yearly_children.value == 1)
			{
			form.yearly_taxfree_edu.value = 1200;
			}
			if(form.yearly_children.value >= 2)
			{
			form.yearly_taxfree_edu.value = 2400;
			}

			form.yearly_taxable_edu.value = +form.yearly_edu_recd.value - +form.yearly_taxfree_edu.value;
		}
		if(form.yearly_edu_recd.value > 2400 && form.yearly_edu_recd.value > 0)
		{
			if(form.yearly_children.value == 1)
			{
				form.yearly_taxfree_edu.value = 1200;
				form.yearly_taxable_edu.value = +form.yearly_edu_recd.value - 1200;
			}
			if(form.yearly_children.value >= 2)
			{
				form.yearly_taxfree_edu.value = 2400;
				form.yearly_taxable_edu.value = +form.yearly_edu_recd.value - 2400;
			}

			form.yearly_taxable_edu.value = +form.yearly_edu_recd.value - +form.yearly_taxfree_edu.value;
		}
			
			document.taxcalc.taxable_education.value = +form.yearly_taxable_edu.value;
			calctax();

	}

function calcmonthlyedu(month)
	{
		//alert(month);
		var form = document.educalc;

		var mchildren = month + "_children"
		var medu_recd = month + "_edu_recd";
		var mtaxfree_edu = month + "_taxfree_edu";
		var mtaxable_edu = month + "_taxable_edu";

		if(form[medu_recd].value <= 200 && form[medu_recd].value > 0)
		{
			if(form[mchildren].value == 1)
			{
			form[mtaxfree_edu].value = 100;
			}
			if(form[mchildren].value >= 2)
			{
			form[mtaxfree_edu].value = 200;
			}

			form[mtaxable_edu].value = +form[medu_recd].value - +form[mtaxfree_edu].value;
		}
		if(form[medu_recd].value > 200 && form[medu_recd].value > 0)
		{
			if(form[mchildren].value == 1)
			{
				form[mtaxfree_edu].value = 100;
				form[mtaxable_edu].value = +form[mtaxfree_edu].value - 100;
			}
			if(form[mchildren].value >= 2)
			{
				form[mtaxfree_edu].value = 200;
				form[mtaxable_edu].value = +form[mtaxfree_edu].value - 200;
			}

			form[mtaxable_edu].value = +form[medu_recd].value - +form[mtaxfree_edu].value;
		}
		
		

		form.monthly_edu_recd.value = +form.apr_edu_recd.value + +form.may_edu_recd.value + +form.jun_edu_recd.value + +form.jul_edu_recd.value + +form.aug_edu_recd.value + +form.sept_edu_recd.value + +form.oct_edu_recd.value + +form.nov_edu_recd.value + +form.dec_edu_recd.value + +form.jan_edu_recd.value + +form.feb_edu_recd.value + +form.mar_edu_recd.value;

		form.monthly_taxfree_edu.value = +form.apr_taxfree_edu.value + +form.may_taxfree_edu.value + 				+form.jun_taxfree_edu.value + +form.jul_taxfree_edu.value + +form.aug_taxfree_edu.value + +form.sept_taxfree_edu.value + +form.oct_taxfree_edu.value + +form.nov_taxfree_edu.value + +form.dec_taxfree_edu.value + +form.jan_taxfree_edu.value + +form.feb_taxfree_edu.value + +form.mar_taxfree_edu.value;

		form.monthly_taxable_edu.value = +form.apr_taxable_edu.value + +form.may_taxable_edu.value + 				+form.jun_taxable_edu.value + +form.jul_taxable_edu.value + +form.aug_taxable_edu.value + +form.sept_taxable_edu.value + +form.oct_taxable_edu.value + +form.nov_taxable_edu.value + +form.dec_taxable_edu.value + +form.jan_taxable_edu.value + +form.feb_taxable_edu.value + +form.mar_taxable_edu.value;

		document.taxcalc.taxable_education.value = +form.monthly_taxable_edu.value;

		calctax();

	}

	function chkinvestments()
	{
		var form = document.taxcalc;

		if(form.investments.value > 100000)
		{
			alert("Deductions under Section 80C is limited upto Rs. 100000 /- only");
			form.investments.value = 100000;
		}
		calctax();

	}

	function chkmedical() 
	{
		var form = document.taxcalc;

		if(form.category.value == 'Senior')
		{
			if(form.medical.value > 20000)
			{
				alert("Maximum Medical Insurance limit is Rs. 20000 for Senior Citizens");
				form.medical.value = 20000;
			}
		}
		else
		{
			if(form.medical.value > 15000)
			{
				alert("Maximum Medical Insurance limit is Rs. 15000 for General and Female Category");
				form.medical.value = 15000;
			}
		}

	}

	function chktelephone() 
	{
		var form = document.taxcalc;

		
			if(form.telephone.value > 15000)
			{
				alert("Maximum Telephone Reimbursement limit is Rs. 15000");
				form.telephone.value = 15000;
			}

	}