// JavaScript Document


//Volume / Area conversion calculator

function process_rect_form(form){
    var firstvalue = 0;
    
    if (form.width.value == "") 
    {
		var message = "Please fill in the width field"
		alert(message);
		form.width.focus();
		return false;
	}
  if (form.length.value == "") 
    {
		var message = "Please fill in the length field"
		alert(message);
		form.length.focus();
		return false;
	}
    if (form.depth.value == "")  
    {
		var message = "Please fill in the depth field"
		alert(message);
		form.depth.focus();
		return false;
	}
    else
    {
		
		var length = form.length.value;
		var width = form.width.value;
		var depth = form.depth.value;
		var material_conv = form.material.value

        // Multiply area by 144 to convert to square inches.
        // There are 46656 cubic inches to the cubic yard...
        // Before rounding, multiply by 100 (144 becomes 14400) to preserve 2 decimal positions.
        // After rounding, divide by 100 to restore the 2 decimal positions.
       if (material_conv == 1.081)
	{
		 form.elements[6].value = "cubic yards";
	}
       else 
       {
		 form.elements[6].value = "tons";
       }		

       form.elements[5].value =  Math.round(length * width * depth * 14400 / 46656 * material_conv) / 100 ;

    }
    return true;
}


function process_round_form(form){
    var firstvalue = 0;
    
    if (form.diameter.value == "") 
    {
		var message = "Please fill in the diameter field"
		alert(message);
		form.width.focus();
		return false;
	}

    if (form.depth.value == "")  
    {
		var message = "Please fill in the depth field"
		alert(message);
		form.depth.focus();
		return false;
	}
    else
    {
		
		var area = Math.PI*Math.pow(form.diameter.value/2,2);
		var depth = form.depth.value;
		var material_conv = form.material.value

        // Multiply area by 144 to convert to square inches.
        // There are 46656 cubic inches to the cubic yard...
        // Before rounding, multiply by 100 (144 becomes 14400) to preserve 2 decimal positions.
        // After rounding, divide by 100 to restore the 2 decimal positions.
       if (material_conv == 1.081)
	{
		 form.elements[5].value = "cubic yards";
	}
       else 
       {
		 form.elements[5].value = "tons";
       }		

       form.elements[4].value =  Math.round(area * depth * 14400 / 46656 * material_conv) / 100 ;

    }
    return true;
}


function process_triangle_form(form){
    var firstvalue = 0;
    
    if (form.side_one.value == "") 
    {
		var message = "Please fill in the first side field"
		alert(message);
		form.side_one.focus();
		return false;
	}
    if (form.side_two.value == "") 
    {
		var message = "Please fill in the second side field"
		alert(message);
		form.side_two.focus();
		return false;
	}

    if (form.depth.value == "")  
    {
		var message = "Please fill in the depth field"
		alert(message);
		form.depth.focus();
		return false;
	}
    else
    {
		
		var area = (form.side_one.value * form.side_two.value)/2;
		var depth = form.depth.value;
		var material_conv = form.material.value

        // Multiply area by 144 to convert to square inches.
        // There are 46656 cubic inches to the cubic yard...
        // Before rounding, multiply by 100 (144 becomes 14400) to preserve 2 decimal positions.
        // After rounding, divide by 100 to restore the 2 decimal positions.
       if (material_conv == 1.081)
	{
		 form.elements[6].value = "cubic yards";
	}
       else 
       {
		 form.elements[6].value = "tons";
       }		

       form.elements[5].value =  Math.round(area * depth * 14400 / 46656 * material_conv) / 100 ;

    }
    return true;
}



function reset_round_form(form) {
    clear_form(form);
    form.elements[0].value = 0;
    form.elements[1].value = 0;
    process_round_form(form);
    return true;
}

function reset_rect_form(form) {
    clear_form(form);
    form.elements[0].value = 0;
    form.elements[1].value = 0;
    form.elements[2].value = 0;
    process_rect_form(form);
    return true;
}

function reset_triangle_form(form) {
    clear_form(form);
    form.elements[0].value = 0;
    form.elements[1].value = 0;
    form.elements[2].value = 0;
    process_triangle_form(form);
    return true;
}

function clear_form(form) {
    for (var i = 1; i <= form.count; i++) form.elements[i].value = "";
    return true;
}

function checkmaterialtype(form) {
    if (form.material.value == "1.08" || form.material.value == ".6")  
    {
        if (form.depth.value == ""){
		form.depth.value = 3;
		}	
	}
	return true;
}