var total_box=1;
  var boxes_ar=new Array(0,1); 
  var data_ar=new Array();
  
function RemoveBox(num){
   selection=document.getElementById('box_'+num);
   selection.parentNode.removeChild(selection);
    delete(boxes_ar[num]);    
}

 function AddNewBox(){
    area=document.getElementById('boxes_list');
    
	getDataValues();
	total_box+=1;
	numx=total_box;	
	boxes_ar[total_box]=numx;

	area.innerHTML+="<table border='0' cellspacing='0' cellpadding='3' id='box_"+numx+"' class='form_filed_text' style='border:1px solid #ffffff'><tr bgcolor='#CCCCCC'><td rowspan='2' bgcolor='#CCCCCC' class='form_filed_text'>&nbsp;</td><td>Length: <input name='box_length_"+numx+"' id='box_length_"+numx+"' type='text' class='form_input_text' size='6'></td><td>Width: <input name='box_width_"+numx+"' id='box_width_"+numx+"' type='text' class='form_input_text' size='6'></td><td>Height: <input name='box_height_"+numx+"' id='box_height_"+numx+"' type='text' class='form_input_text' size='6'></td><td rowspan='2' bgcolor='#CCCCCC'><a href='javascript:RemoveBox("+numx+");'><img src='"+_S2U_base_PATH+"images/icons/drop_red.png' alt='Remove' width='17' height='17' border='0'></a></td></tr><tr bgcolor='#CCCCCC'><td colspan='3' align='center' bgcolor='#CCCCCC'><table border='0' cellpadding='3' cellspacing='0' class='form_filed_text'><tr><td >Weight: <input name='box_weight_"+numx+"' id='box_weight_"+numx+"' type='text' class='form_input_text' size='6'></td><td >Number of boxes of same size: <input name='box_num_"+numx+"' id='box_num_"+numx+"' type='text' class='form_input_text' size='6'></td></tr></table></td></tr></table>";	
	
	if (parent.document.getElementById('content_frame')){ parent.document.getElementById('content_frame').style.height = (parseFloat(document.body.scrollHeight)) + 'px'; parent.document.getElementById('content_frame').style.width = (parseFloat(document.body.scrollWidth)) + 'px'}
	
	setDataValues()
 }
 
 function Calculate(){
  tw=0;tv=0;tn=0;
  err=false;
  for(i=1;i<boxes_ar.length;i++)
  if (boxes_ar[i])
  {  
		   l=GetObject("box_length_"+boxes_ar[i]);
		   w=GetObject("box_width_"+boxes_ar[i]);
		   h=GetObject("box_height_"+boxes_ar[i]);
		   wh=GetObject("box_weight_"+boxes_ar[i]);
		   n=GetObject("box_num_"+boxes_ar[i]);
		  
		  l.className='form_input_text';w.className='form_input_text';h.className='form_input_text';n.className='form_input_text';wh.className='form_input_text'; 
		  
		   if (!parseFloat(l.value)||l.value=='')
			{ l.className='input_text_err'; err=true;}
		
		   if (!parseFloat(w.value)||w.value=='')
			{ w.className='input_text_err'; err=true;}
			
		   if (!parseFloat(h.value)||h.value=='')
			{ h.className='input_text_err'; err=true;}
			
		   if (!parseFloat(wh.value)||wh.value=='')
			{ wh.className='input_text_err'; err=true;}
		
		   if (!parseFloat(n.value)||n.value=='')
			{ n.className='input_text_err'; err=true;}
			
			  tv+=
				 parseFloat(l.value)*
				 parseFloat(w.value)*
				 parseFloat(h.value)*parseFloat(n.value)/1728;
				 
			  tw+=parseFloat(wh.value)*parseFloat(n.value);
  	 		  
			  tn+=parseFloat(n.value);
		  } 
		 
		 if (err) alert("Field marked with red is incorrect!"); 
		 else 
		 {
			  document.getElementById("total_volume").value=Math.round(tv);
			  document.getElementById("total_weight").value=tw;
			  document.getElementById("boxes_num").value=tn;
		  }
 }
 
 
 
 function getDataValues(){	
	 for(i=0;i<=boxes_ar.length;i++) 	 
	  if (GetObject("box_length_"+boxes_ar[i]))
	  {		
           l=GetObject("box_length_"+boxes_ar[i]).value;
		   w=GetObject("box_width_"+boxes_ar[i]).value;
		   h=GetObject("box_height_"+boxes_ar[i]).value;
		   wh=GetObject("box_weight_"+boxes_ar[i]).value;
		   n=GetObject("box_num_"+boxes_ar[i]).value;
		   data_ar[boxes_ar[i]]=new Array(l,w,h,wh,n);
	  }	  	 
 }

 function setDataValues(){	
   for(i=0;i<=boxes_ar.length;i++) 
	 if (boxes_ar[i])
	  {				   
		  GetObject('box_length_'+boxes_ar[i]).value=data_ar[boxes_ar[i]][0];          
		   GetObject("box_width_"+boxes_ar[i]).value=data_ar[boxes_ar[i]][1];          
		   GetObject("box_height_"+boxes_ar[i]).value=data_ar[boxes_ar[i]][2];          
		   GetObject("box_weight_"+boxes_ar[i]).value=data_ar[boxes_ar[i]][3];          
		   GetObject("box_num_"+boxes_ar[i]).value=data_ar[boxes_ar[i]][4];          
	  }
	  
 }