function calc(f) // id of the form we're working with
{
	pound = document.getElementById('pound').value;
	switch(f)
	{
		case 'fp': // selling
			p = document.getElementById('fpp').value;
			if(isNaN(p))
			{
				document.getElementById('fptp').value='Invalid Number';
				document.getElementById('fptc').value='';
				document.getElementById('fptl').value='';
				document.getElementById('fptw').value='';
				document.getElementById('fpte').value='';
				document.getElementById('fptb').value='';
				document.getElementById('fptf').value='';
				document.getElementById('fptt').value='';
				document.getElementById('fpth').value='';
				document.getElementById('fpts').value='';
				return;
			}
			else
			{
				if(p == 0)
				{
					document.getElementById('fptp').value='';
					document.getElementById('fptc').value='';
					document.getElementById('fptl').value='';
					document.getElementById('fptw').value='';
					document.getElementById('fpte').value='';
					document.getElementById('fptb').value='';
					document.getElementById('fptf').value='';
					document.getElementById('fptt').value='';
					document.getElementById('fpsth').value='';
					document.getElementById('fpth').value='';
					document.getElementById('fpsts').value='';
					document.getElementById('fpts').value='';
					return;
				}
				else if(p <= 90000)
				{
					document.getElementById('fptp').value=pound+'295 +VAT';
					l = 295*1.175;
				}
				else if(p <= 120000)
				{
					document.getElementById('fptp').value=pound+'325 +VAT';
					l = 325*1.175;
				}
				else if(p <= 240000)
				{
					document.getElementById('fptp').value=pound+'350 +VAT';
					l = 350*1.175;
				}
				else if(p <= 300000)
				{
					document.getElementById('fptp').value=pound+'375 +VAT';
					l = 375*1.175;
				}
				else if(p <= 350000)
				{
					document.getElementById('fptp').value=pound+'400 +VAT';
					l = 400*1.175;
				}
				else if(p <= 400000)
				{
					document.getElementById('fptp').value=pound+'425 +VAT';
					l = 425*1.175;
				}
				else if(p <= 450000)
				{
					document.getElementById('fptp').value=pound+'450 +VAT';
					l = 450*1.175;
				}
				else if(p <= 500000)
				{
					document.getElementById('fptp').value=pound+'475 +VAT';
					l = 475*1.175;
				}
				else
				{   
				    pr = Math.round(p*0.0015);
					document.getElementById('fptp').value=pound+pr+' +VAT';
					l = Math.round(p*0.0015*1.175);
				}
				
				t = Math.round( (23.99 + l )*100) / 100;
				document.getElementById('fptc').value = pound+t;
				t = Math.round( (t + 65.00 )*100) / 100;
				document.getElementById('fptl').value = pound+t;
				if(document.getElementById('fpw').checked==1)
				{
					t = Math.round( (t+29.38)*100 )/100;
					document.getElementById('fptw').value = pound+t;
				}
				else
				{
					document.getElementById('fptw').value ='';
				}

				if(document.getElementById('fpe').checked==1)
				{
					t = Math.round( (t+43.00)*100 )/100;
					document.getElementById('fpte').value = pound+t;
				}
				else
				{
					document.getElementById('fpte').value='';
				}
				
				if(document.getElementById('fpx').checked==1)
				{
					t = Math.round( (t+15.00)*100 )/100;
					document.getElementById('fptx').value = pound+t;
				}
				else
				{
					document.getElementById('fptx').value ='';
				}
				
				b = document.getElementById('fpb').selectedIndex+1;

				t = Math.round( (( b* 3.05)+t) * 100) / 100
				document.getElementById('fptb').value = pound+t ;
				
				t = Math.round( (t+5.20) * 100) / 100;
				document.getElementById('fptf').value=pound+t;
				
				t = Math.round( (t+23.50) * 100) / 100;
				document.getElementById('fptt').value=pound+t;
				
				if(p <= 50000)
				{
					h = 40.00;
				}
				else if(p <= 80000)
				{
					h = 60.00
				}
				else if(p <= 100000)
				{
					h = 100.00
				}
				else if(p <= 200000)
				{
					h = 150.00;
				}
				else if(p <= 500000)
				{
					h = 220.00
				}
				else if(p <= 1000000)
				{
					h = 420.00;
				}
				else
				{
						h = 700.00;
				}
				
				t = Math.round( (t+h) * 100) / 100;
				document.getElementById('fpsth').value=pound+h;
				document.getElementById('fpth').value=pound+t;
				
				if(p <= 175000)
				{
					s = 0.00;
				}
				else if(p <= 250000)
				{
					s = Math.round((p *1)) / 100
				}
				else if(p <= 500000)
				{
					s = Math.round((p *3)) / 100;
				}
				else
				{
					s = Math.round((p *4)) / 100
				}
				// document.getElementById('fpsts').value=pound+s;
				document.getElementById('fpsts').value= (pound+Math.round(s));
				
				t = Math.round( (t+Math.round(s)) * 100) / 100;
				document.getElementById('fpts').value=(pound+t);
				

				
			}
			break;
			
		case 'fs': // purchasing
			p = document.getElementById('fsp').value;
			if(isNaN(p))
			{
				document.getElementById('fstp').value='Invalid Number';

				return;
			}
			else
			{
				if(p == 0)
				{
					document.getElementById('fstp').value='';
					return;
				}
				else if(p <= 90000)
				{
					document.getElementById('fstp').value=pound+'250 +VAT';
					l = 250*1.175;
				}
				else if(p <= 120000)
				{
					document.getElementById('fstp').value=pound+'275 +VAT';
					l = 275*1.175;
				}
				else if(p <= 240000)
				{
					document.getElementById('fstp').value=pound+'300 +VAT';
					l = 300*1.175;
				}
				else if(p <= 300000)
				{
					document.getElementById('fstp').value=pound+'325 +VAT';
					l = 325*1.175;
				}
				else if(p <= 350000)
				{
					document.getElementById('fstp').value=pound+'350 +VAT';
					l = 350*1.175;
				}
				else if(p <= 400000)
				{
					document.getElementById('fstp').value=pound+'375 +VAT';
					l = 375*1.175;
				}
				else if(p <= 450000)
				{
					document.getElementById('fstp').value=pound+'400 +VAT';
					l = 400*1.175;
				}
				else if(p <= 500000)
				{
					document.getElementById('fstp').value=pound+'425 +VAT';
					l = 425*1.175;
				}
				else
				{
				    pri = Math.round(0.01*p);
					document.getElementById('fstp').value=pound+pri+' +VAT';
					l = Math.round(pri*1.175);
				}
				
				//fstt
				//fsth
				
				t = Math.round((l+23.50)*100) / 100;
				document.getElementById('fstt').value = pound+t;
				
				t = Math.round((t+7.95)*100) / 100;
				document.getElementById('fsth').value = pound+t;
			}
			break;
	}
}


function change(id)
{
	switch(id)
	{
		case 'p':
			document.getElementById('calc_lt').className='calc_ltc';
			document.getElementById('calc_rt').className='calc_rt';
			document.getElementById('calc_r').style.display = 'none';
			document.getElementById('calc_l').style.display = 'block';
			break
			
		case 's':
			document.getElementById('calc_rt').className='calc_rtc';
			document.getElementById('calc_lt').className='calc_lt';
			document.getElementById('calc_l').style.display = 'none';
			document.getElementById('calc_r').style.display = 'block';
			break;
	}
}