Added the ability to add cost through take/remove operations. Also added a reverse cost rollback function

Author: stevebauman

src/Stevebauman/Inventory/Traits/InventoryStockTrait.php

@@ -33,7 +33,7 @@ trait InventoryStockTrait {
      *
      * @var
      */
-    public $beforeQuantity = 0;
+    private $beforeQuantity = 0;
 
     /**
      * Stores the reason for updating / creating a stock
@@ -114,6 +114,9 @@ public function postCreate()
         }
     }
 
+    /**
+     * Generates a stock movement after a stock is updated
+     */
     public function postUpdate()
     {
         $this->generateStockMovement($this->beforeQuantity, $this->quantity, $this->reason, $this->cost);
@@ -143,27 +146,29 @@ public function updateQuantity($quantity, $reason= '', $cost = 0)
      *
      * @param $quantity
      * @param string $reason
-     * @return InventoryStock
+     * @param int $cost
+     * @return $this|bool|InventoryStockTrait
      */
-    public function remove($quantity, $reason= '')
+    public function remove($quantity, $reason= '', $cost = 0)
     {
-        return $this->take($quantity, $reason);
+        return $this->take($quantity, $reason, $cost);
     }
 
     /**
      * Processes a 'take' operation on the current stock
      *
      * @param $quantity
      * @param string $reason
-     * @return InventoryStock
+     * @param int $cost
+     * @return $this|bool|InventoryStockTrait
      * @throws InvalidQuantityException
      * @throws NotEnoughStockException
      */
-    public function take($quantity, $reason = '')
+    public function take($quantity, $reason = '', $cost = 0)
     {
         if($this->isValidQuantity($quantity) && $this->hasEnoughStock($quantity)) {
 
-            return $this->processTakeOperation($quantity, $reason);
+            return $this->processTakeOperation($quantity, $reason, $cost);
 
         }
     }
@@ -366,7 +371,7 @@ private function processUpdateQuantityOperation($quantity, $reason = '', $cost =
 
             $taking = $this->quantity - $quantity;
 
-            return $this->take($taking, $reason);
+            return $this->take($taking, $reason, $cost);
 
         }
     }
@@ -376,9 +381,10 @@ private function processUpdateQuantityOperation($quantity, $reason = '', $cost =
      *
      * @param $taking
      * @param string $reason
+     * @param int $cost
      * @return $this|bool
      */
-    private function processTakeOperation($taking, $reason = '')
+    private function processTakeOperation($taking, $reason = '', $cost = 0)
     {
         $left = $this->quantity - $taking;
 
@@ -395,6 +401,8 @@ private function processTakeOperation($taking, $reason = '')
 
         $this->setReason($reason);
 
+        $this->setCost($cost);
+
         $this->dbStartTransaction();
 
         if($this->save()) {
@@ -513,6 +521,14 @@ private function processRollbackOperation($movement, $recursive = false)
 
         $this->setReason($reason);
 
+        if(config('inventory::rollback_cost')) {
+
+            $this->setCost($movement->cost);
+
+            $this->reverseCost();
+
+        }
+
         $this->dbStartTransaction();
 
         if($this->save()) {
@@ -589,6 +605,22 @@ private function setCost($cost = 0)
         $this->cost = $cost;
     }
 
+    /**
+     * Reverses the cost of a movement
+     */
+    private function reverseCost()
+    {
+        if($this->isPositive($this->cost)) {
+
+            $this->setCost(-abs($this->cost));
+
+        } else {
+
+            $this->setCost(abs($this->cost));
+
+        }
+    }
+
     /**
      * Sets the reason attribute
      *

src/config/config.php

@@ -15,6 +15,14 @@
      */
     'allow_duplicate_movements' => true,
 
+    /*
+     * When set to true, this will reverse the cost in the rolled back movement.
+     *
+     * For example, if the movement's cost that is being rolled back is 500, the rolled back
+     * movement will be -500.
+     */
+    'rollback_cost' => true,
+
     /*
      * Default reason to give when creating a new inventory stock
      */

src/lang/en/reasons.php

@@ -12,4 +12,5 @@
     'change' => 'Stock Adjustment',
 
     'rollback' => 'Rolled back to movement ID: :id on :date',
+
 );