[TASK] Show collected duck stickers

Assets/DuckStickerManager.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+using UnityEngine.Events;
+
+[Serializable]
+public class DuckStickerEvent : UnityEvent<DuckStickerData>
+{
+}
+
+public class DuckStickerManager : MonoBehaviour
+{
+    public List<DuckStickerData> duckStickers;
+
+    public DuckStickerEvent stickerCollected;
+    
+    private readonly Dictionary<DuckStickerData, int> _collectedStickers = new Dictionary<DuckStickerData, int>();
+    
+    private static DuckStickerManager _instance;
+    public static DuckStickerManager Instance
+    {
+        get { return _instance;  }
+        private set { _instance = value; }
+    }
+
+    public IEnumerable<DuckStickerData> CollectedStickers
+    {
+        get { return duckStickers.Where(d => GetStickerCollectedCount(d) > 0); }
+    }
+
+    public DuckStickerManager()
+    {
+        Instance = this;
+    }
+
+    private void Awake()
+    {
+        foreach (var sticker in duckStickers)
+        {
+            _collectedStickers.Add(sticker, PlayerPrefs.GetInt("sticker." + sticker.Id));
+        }
+    }
+
+    public void OnStickerCollected(DuckStickerData sticker)
+    {
+        _collectedStickers[sticker]++;
+        PlayerPrefs.SetInt("sticker." + sticker.Id, _collectedStickers[sticker]);
+        
+        stickerCollected.Invoke(sticker);
+    }
+
+    public int GetStickerCollectedCount(DuckStickerData sticker)
+    {
+        return _collectedStickers.ContainsKey(sticker) ? _collectedStickers[sticker] : 0;
+    }
+}