How to add a new box to admin/categories

[♥14steve14]

I may be wanting to bite of more than I can chew here. I am trying to include a feature in the admin categories page that will make it easier for my new staff member to compare various supplier prices.

 

I use the margin report add on which includes a cost price which is added in the admin/categories.php page. What I want to try and do is to add a cost price and a cost price including VAT (20%), which will also be entered into the database for the margin report add on. The cost price is already installed and working.

 

I dont particularly want to sit with a calculaor to work this out every time a product is added, or current products are updated.

 

So what I really want is a box above the cost price which will contain a price, then turn the cost price box to a box that will include the price plus the VAT which will then be used in the margin report add on.

 

I have tried looking to see how the product gross price is calculated in the admin/categories.php file so that I can copy and work with that, but I cannot seem to get the box to fill.

 

Does anyone have any help or advice on how to achieve this? I hope I have explained this well enough

[♥14steve14]

Been playing a bit. I have coppied the install again for the products_cost code that was added during the margin report addon. Changed product cost to product_cost_net and added a new table to the database. This figure can now be manually entered into the database and all is working fine.

 

Now is there a way to have the price for the cost_price automatically fill from the cost_price_gross times the vat rate of 20%.

 

The code for the products_cost is

 

<tr bgcolor="#ebebff">
	    <td class="main"><?php echo TEXT_PRODUCTS_PRICE_COST; ?></td>
	    <td class="main"><?php echo tep_draw_separator('pixel_trans.gif', '24', '15') . ' ' . tep_draw_input_field('products_cost', $pInfo->products_cost, ''); ?></td>
	  </tr>

[♥14steve14]

With help from another forum, I eventually got this working. The cost price box now adds vat to the price and automatically fills the box, just like the gross price box on the categories page.