evershade/Assets/Data/ScriptableObjects/ItemDatabase.cs

using System.Collections.Generic;
using System.Linq;
using Data.ScriptableObjects.Items;
using Types.Items;
using UnityEngine;

namespace Data.ScriptableObjects
{
    [CreateAssetMenu(fileName = "ItemDatabase", menuName = "Game/Item Database")]
    public class ItemDatabase : ScriptableObject
    {
        public static ItemDatabase Instance;
        [SerializeField] private int lastAssignedId;

        private readonly Dictionary<int, GameItem> _itemDictionary = new();
        [SerializeField] public List<GameItem> AllItems = new();


        public void Awake()
        {
            if (Instance == null) Instance = this;
        }

        private void OnEnable()
        {
            _itemDictionary.Clear();
            foreach (var item in AllItems) _itemDictionary[item.ID] = item;
        }

        public int GetNextId()
        {
            return ++lastAssignedId;
        }


        public void AddItem(GameItem item)
        {
            if (!_itemDictionary.ContainsKey(item.ID))
            {
                AllItems.Add(item);
                _itemDictionary[item.ID] = item;
            }
        }

        public GameItem GetItemById(int id)
        {
            if (_itemDictionary.TryGetValue(id, out var item)) return item.Clone();
            return null;
        }

        public GameItem GetItemByName(string searchName)
        {
            return AllItems.Find(item => item.ItemName == searchName)?.Clone();
        }

        public void RemoveItem(GameItem item)
        {
            if (_itemDictionary.ContainsKey(item.ID))
            {
                AllItems.Remove(item);
                _itemDictionary.Remove(item.ID);
            }
        }

        public int GetMaxId()
        {
            lastAssignedId = 0;
            foreach (var item in AllItems)
                if (item.ID > lastAssignedId)
                    lastAssignedId = item.ID;

            return lastAssignedId;
        }

        public void LoadAllItems()
        {
            AllItems.Clear();
            var scriptableGameItems = Resources.LoadAll<GameItemSo>("GameItems");

            // loop over them all, convert each to GameItem and add to AllItems
            foreach (var scriptableGameItem in scriptableGameItems)
            {
                var gameItem = scriptableGameItem.Clone();
                AllItems.Add(gameItem);
            }

            // AllItems.AddRange();
            GetMaxId();
            if (lastAssignedId == 0) lastAssignedId = GetNextId();

            // check ids of all items.
            // id should not be zero, reassign to lastAssignedId if it is.
            foreach (var item in AllItems.Where(item => item.ID == 0))
                item.ID = GetNextId();
            // EditorUtility.SetDirty(item);

            foreach (var item in AllItems) _itemDictionary[item.ID] = item;
        }


        // get random item by type
        public GameItem GetRandomItemByType(ItemType type)
        {
            var items = AllItems.FindAll(item => item.Type == type);
            return items[Random.Range(0, items.Count - 1)].Clone();
        }
    }
}