Product price / free delivery in custom module

[cilecek]

hello,
i am trying to modify custom bought module and i have stucked.
 
i have an array of carriers with name and price;

if carrier price = 0, then show "free delivery" else show price

 

1/ i need to show "free delivery" also when product price > free delivery limit 

(free delivery limit should be taken automatically from settings or manually hard coded)

 

2/ showing "free delivery" also when there is product price < free delivery limit but (cart ammount + product price) > free delivery limit

 

 

any clues how to do it in .tpl? 

{foreach from=$final_carriers item=carrier}
  {if $carrier.price == 0 }
    <li>{$carrier.name} : <strong>Free delivery!</strong></li>
  {else}
    <li>{$carrier.name} : <strong>{convertPrice price=$carrier.price}</strong></li>
  {/if}
{/foreach}