var prices = new Array();

prices['none'] = '0.00';  
prices['Auckland Poster'] = '29.95';  
prices['Wellington Poster'] = '29.95';  
prices['Christchurch Poster'] = '29.95';  
prices['Dunedin Poster'] = '29.95';  

function formatTotal (total) 
{ 
var i=0;
var k=0;
var result="" + (total + 0.00500000001 ); 
var j=result.indexOf ('.'); 
if (j<0) 
  { 
  result+='.00'; 
  } 
else 
  { 
  result=result.slice ( 0, j + 3 ); 
  k=3-(result.length - j ); 
  for (i=0; i<k; i++) 
    {
    result+='0'; 
    }
  } 
return result; 
} 


function doRecalcTotal()
{
var subtotal=0;
var gst=0;
var total=0;
for (i=1; i <= 5; i++)
   {
   ptr=eval('order.line_' + i + '_total')
   subtotal=subtotal+Number(ptr.value);
   }
subtotal=Math.round(subtotal*100)/100;
ptr=eval('order.subtotal');
if (isNaN(subtotal))
  {
  ptr.value='*error*';
  }
else
  {
  ptr.value=formatTotal(subtotal);
  gst=subtotal*0.125;
  ptr=eval('order.gst');
  ptr.value=formatTotal(gst);
  ptr=eval('order.total');
  ptr.value=formatTotal(subtotal+gst);
  }
}


function doRecalc(i)
{
code=eval('order.line_' + i + '_item.value');
if (code!='none')
  {
  a=eval('order.line_' + i + '_cost');
  a.value=prices[code];
  b=eval('order.line_' + i + '_total');
  c=eval('order.line_' + i + '_units.value');
  b.value=formatTotal(prices[code]*Number(c));
  doRecalcTotal();
  }
else
  {
  a=eval('order.line_' + i + '_cost');
  a.value='';
  b=eval('order.line_' + i + '_total');
  b.value='';
  c=eval('order.line_' + i + '_units');
  b.value='';
  }
}

function doRecalcAll()
{
var i=0;
for (i=1; i <= 5; j++)
   {
   doRecalc(i);
   }
doRecalcTotal();
}


function showLine(i)
{
if (i==1) 
  {
  document.write('Product name: ');
  }
document.write('<select type=text id=line_' + i + '_item class=field style="width:208;" onChange=doRecalc(' + i + ')>');
document.write('<option selected value=none></option>');
document.write('<option value="Auckland Poster">Auckland Poster</option>');
document.write('<option value="Wellington Poster">Wellington Poster</option>');
document.write('<option value="Christchurch Poster">Christchurch Poster</option>');
document.write('<option value="Dunedin Poster">Dunedin Poster</option>');
document.write('</select> ');
document.write('<select type=text id=line_' + i + '_units class=field style="width:75;" onChange=doRecalc(' + i + ')>');   
document.write('<option value=1>1</option>');
document.write('<option value=2>2</option>');
document.write('<option value=3>3</option>');
document.write('<option value=4>4</option>');
document.write('<option value=5>5</option>');
document.write('<option value=6>6</option>');
document.write('<option value=7>7</option>');
document.write('<option value=8>8</option>');
document.write('<option value=9>9</option>');
document.write('<option value=10>10</option>');
document.write('</select> ');
document.write('<input type=text id=line_' + i + '_cost class=field style="width:74;text-align:right;"></input> ');
document.write('<input type=text id=line_' + i + '_total class=field style="width:74;text-align:right;"></input><br>');
}

function doLines()
{
document.write('<td colspan=2 class=field>');
for (i=1;i<=5;i++)
  {
  showLine(i);
  }
document.write('</td>');
}