name key -> unique key for promotion

README.md

@@ -38,7 +38,7 @@ class Model_Purchase extends Kohana_Model_Purchase {
  ));
  }
 }
-```php
+```
 
 And you'll need to add actual promotions to the database. The promtion modle uses single table inheritence to have a different class for each promotion. Each of these has to define "applies_to" and "price_for_purchase_item" which your promotions will have to implement. There is also the ``Model_Promotion_Promocode`` class which gives the promotion the ability to use promo codes which exhaust themselves when are used.
 

classes/Kohana/Model/Promotion.php

@@ -17,7 +17,9 @@ class Kohana_Model_Promotion extends Jam_Model implements Sellable {
  public static function initialize(Jam_Meta $meta)
  {
  $meta
- ->name_key('identifier')
+ ->unique_key(function($key){
+ return is_numeric($key) ? 'id' : 'identifier';
+ })
  ->table('promotions')
  ->associations(array(
  'purchase_items' => Jam::association('hasmany', array(
@@ -59,6 +61,10 @@ public function applies_to(Model_Store_Purchase $purchase)
  throw new Kohana_Exception('Not a valid promotion');
  }
 
+ /**
+ * Build a purchase item for this promotion (inverseof "reference")
+ * @return Model_Purchase_Item
+ */
  public function build_purchase_item()
  {
  return $this->purchase_items->build(array(
@@ -73,6 +79,10 @@ public function currency()
  return $this->currency;
  }
 
+ /**
+ * If the promotion applies to the store_purchase - add a purchase_item for this promotion, otherwise remove the associated purchase item
+ * @param Model_Store_Purchase $store_purchase 
+ */
  public function update_store_purchase(Model_Store_Purchase $store_purchase)
  {
  $promo_item = $this->build_purchase_item();