// Updated 12:30, August 3, 2004
// Ross Olson

function calc(type)
	{
	var form = document.calcForm;
	
	if (type == "usage")
		{

		if (form.u_blocks.value != "")
			{
			form.u_blocks.value = formatdecimal(form.u_blocks.value,0);
			var B6 = form.u_blocks.value;
			form.u_blocks_sbs.value = "$"+formatdecimal((B6*1.95),2);
			if (form.u_blocks.value < 101)
				{
				form.u_blocks_bbs.value = "";
				}
			else {
				form.u_blocks_bbs.value = "$"+formatdecimal(((B6*0.7)+125),2);
				}
			}
		else {
			form.u_blocks_sbs.value = "";
			form.u_blocks_bbs.value = "";
			}


		if (form.u_kwh.value != "")
			{
			form.u_kwh.value = formatdecimalroundup(form.u_kwh.value,-2);
			var C6 = form.u_kwh.value;
			form.u_kwh_sbs.value = "$"+formatdecimal(((C6/100)*1.95),2);
			if (form.u_kwh.value < 10100)
				{
				form.u_kwh_bbs.value = "";
				}
			else {
				form.u_kwh_bbs.value = "$"+formatdecimal(((C6/100)*0.7+125),2);
				}
			}
		else {
			form.u_kwh_sbs.value = "";
			form.u_kwh_bbs.value = "";
			}


		if (form.u_yearly_kwh.value != "" && form.u_percent.value != "")
			{
			form.u_yearly_kwh.value = formatdecimal(form.u_yearly_kwh.value,0);
			form.u_percent.value = formatdecimal(form.u_percent.value,0);
			if (form.u_percent.value > 100) { form.u_percent.value = 100; }

			var A6 = form.u_yearly_kwh.value;
			var D6 = form.u_percent.value; 
			form.u_percent_sbs.value = "$"+formatdecimal((((((D6*0.01)*A6)/12)/100)*1.95),2);
			form.u_percent_bbs.value = "$"+formatdecimal((((((D6*0.01)*A6)/12)/100)*0.7+125),2);
			}
		else {
			form.u_percent_sbs.value = "";
			form.u_percent_bbs.value = "";
			}
		}

	if (type == "cost" && form.c_amount.value != "")
		{
		var A13 = form.c_amount.value;
		var minimumbulkblocks = 101;

		var blockpricestandard = formatdecimal(A13/1.95,0);
		var blockpricebulk = formatdecimal((A13-125)/0.7,0);

		if ( blockpricebulk < minimumbulkblocks ) { blockpricebulk = 0; }

		form.c_standard.value = blockpricestandard;
		form.c_bulk.value = blockpricebulk;
		}

	}

function formatdecimal(num,places)
	{
	roundnum = (Math.round(num * Math.pow(10,places))) / Math.pow(10,places);
	var oldnum = roundnum+""; 
	a = oldnum.split(".");
	if (a[1])
		{
		var before = a[0];
		var after = a[1].slice(0,places);
		if (after.length == 1) {after += "0";}
		var formattednum = before+"."+after;
		return formattednum;
		}
	else {return roundnum;}
	}


function formatdecimalroundup(num,places)
	{
	num = 
	roundnum = (Math.round(Math.ceil(num) * Math.pow(10,places))) / Math.pow(10,places);
	var oldnum = roundnum+""; 
	a = oldnum.split(".");
	if (a[1])
		{
		var before = a[0];
		var after = a[1].slice(0,places);
		if (after.length == 1) {after += "0";}
		var formattednum = before+"."+after;
		return formattednum;
		}
	else {return roundnum;}
	}