added basic inventory system

Assets/Scripts/Inventory.cs

@@ -1,34 +1,84 @@
-using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
-
 public class Inventory : MonoBehaviour
 {
-  [SerializeField] private int slots = 10;
-  [SerializeField] private int stackSize = 100;
-  [SerializeField] private List<Item> items = new List<Item>();
+  public int maxSlots = 20; // maximum number of slots in the inventory
+  public List<InventoryItem> items = new List<InventoryItem>(); // list of items in the inventory
 
-
-  public Item Add(Item item)
+  // adds an item to the inventory, returns the quantity of items which could not be added
+  public int Add(Item item, int count)
   {
-    foreach (Item i in items)
+    int remainingCount = count;
+
+    // check if the item is stackable
+    if (item.stackable)
     {
-      if (i.uuid == item.uuid) // item already is in list
+      // look for an existing stack of the same item in the inventory
+      foreach (InventoryItem invItem in items)
       {
-        if (i.quantity + item.quantity <= stackSize)
-        {// enough space
-          i.quantity += item.quantity;
-          item.quantity = 0;
-        }
-        else
-        {// Not enough space
-          i.quantity = stackSize;
-          item.quantity = Mathf.Max(0, i.quantity - item.quantity);
+        if (invItem.item == item && invItem.count < item.maxStackSize)
+        {
+          // add as many items as possible to the stack
+          int space = item.maxStackSize - invItem.count;
+          int toAdd = Mathf.Min(space, remainingCount);
+          invItem.count += toAdd;
+          remainingCount -= toAdd;
+
+          // exit the loop if all items have been added
+          if (remainingCount == 0)
+          {
+            return 0;
+          }
         }
       }
     }
-    return item;
 
+    // if there is still remaining count, add new stacks of the item
+    while (remainingCount > 0 && items.Count < maxSlots)
+    {
+      int toAdd = Mathf.Min(item.maxStackSize, remainingCount);
+      items.Add(new InventoryItem(item, toAdd));
+      remainingCount -= toAdd;
+    }
+
+    // return the quantity of items which could not be added
+    return remainingCount;
   }
 
+
+  // removes an item from the inventory, returns the quantity of items which could not be removed
+  public int Remove(Item item, int count)
+  {
+    int remainingCount = count;
+
+    // look for an existing stack of the item in the inventory
+    for (int i = 0; i < items.Count; i++)
+    {
+      InventoryItem invItem = items[i];
+      if (invItem.item == item)
+      {
+        // remove as many items as possible from the stack
+        int toRemove = Mathf.Min(invItem.count, remainingCount);
+        invItem.count -= toRemove;
+        remainingCount -= toRemove;
+
+        // remove the stack if it's now empty
+        if (invItem.count == 0)
+        {
+          items.RemoveAt(i);
+        }
+
+        // exit the loop if all items have been removed
+        if (remainingCount == 0)
+        {
+          return 0;
+        }
+      }
+    }
+
+    // return the quantity of items which could not be removed
+    return remainingCount;
+  }
 }
+
+