var imperial;
var ie4 = ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4 ));

var subtotala=0;
var subtotalb=0;
var consheight=0;
var constype=0;
var floor_area=0;
var wall_length=0;



var floorm = new Array();
floorm['00'] = '113'; 
floorm['01'] = '116';
floorm['02'] = '119';
floorm['03'] = '122';
floorm['10'] = '90';
floorm['11'] = '93';	 
floorm['12'] = '96';
floorm['13'] = '99';
floorm['20'] = '76';
floorm['21'] = '79';
floorm['22'] = '82';
floorm['23'] = '85';	 


var floori = new Array();
floori['00'] = '10.2'; 
floori['01'] = '10.4';
floori['02'] = '10.6';
floori['03'] = '10.8';
floori['10'] = '8.2';
floori['11'] = '8.4';	 
floori['12'] = '8.6';
floori['13'] = '8.8';
floori['20'] = '6.9';
floori['21'] = '7.1';
floori['22'] = '7.3';
floori['23'] = '7.5';	 


var wallsm = new Array();
wallsm['00'] = '130'; 
wallsm['01'] = '150';
wallsm['02'] = '170';
wallsm['03'] = '190';
wallsm['10'] = '98';
wallsm['11'] = '113';	 
wallsm['12'] = '128';
wallsm['13'] = '143';
wallsm['20'] = '78';
wallsm['21'] = '89';
wallsm['22'] = '100';
wallsm['23'] = '111';


var wallsi = new Array();
wallsi['00'] = '39'; 
wallsi['01'] = '45';
wallsi['02'] = '51';
wallsi['03'] = '57';
wallsi['10'] = '30';
wallsi['11'] = '34';	 
wallsi['12'] = '38';
wallsi['13'] = '42';
wallsi['20'] = '23';
wallsi['21'] = '26';
wallsi['22'] = '29';
wallsi['23'] = '32';


	  
function init()
{	
	if (document.heatcalc.elements["resultboxi"])	
		imperial = true;	
	else
		imperial = false;		
	consheight=0;
	constype=0;
	wall_length=0;
	floor_area=0;
	subtotala=0;
	subtotalb=0;
		
}


function calculate()
{
	floor_area = document.heatcalc.floorarea.value;
	wall_length = document.heatcalc.walllength.value;
	consheight = document.heatcalc.height.value;
	constype = document.heatcalc.type.value;
	subtotala = step1();
	//alert(subtotala);
	subtotalb = step2();
	//alert(subtotalb);		
	result = subtotala+subtotalb;
	if (document.heatcalc.bground.checked)
		result = result * 0.6;			
	if (imperial)
		document.heatcalc.resultboxi.value = Math.round(result);
	else
		document.heatcalc.resultboxm.value = Math.round(result);
}


function step1()
{
	if (imperial)
	{
		floor_tabval = floori[constype + consheight];
		subtotala = floor_tabval * floor_area;
	}
	else
	{
		floor_tabval = floorm[constype + consheight];
		subtotala = floor_tabval * floor_area;	
	}
	
	return subtotala;	
}

function step2()
{
	if (imperial)
	{
		wall_tabval = wallsi[constype + consheight];
		subtotalb = wall_tabval * wall_length;
	}
	else
	{
		wall_tabval = wallsm[constype + consheight];
		subtotalb = wall_tabval * wall_length;	
	}
	
	return subtotalb;
}


function reset()
{
	init();
	document.heatcalc.reset();
}