Add ItemCategory form

app/Item.php

@@ -31,4 +31,22 @@ class Item extends Model
     {
         return \App\ItemCategory::find($this->category_id);
     }
+
+    public function available()
+    {
+
+        return $this->quantity - $this->booked();
+    }
+
+    public function booked()
+    {
+        $nbBooked = 0;
+
+        foreach ($this->bookings() as $b)
+        {
+            $nbBooked = $nbBooked + $b->amount;
+        }
+
+        return $nbBooked;
+    }
 }