PkmnLibRSharp/PkmnLibRSharp/StaticData/Libraries/DataLibrary.cs

using System;
using System.Collections.Generic;
using PkmnLibSharp.Utils;

namespace PkmnLibSharp.StaticData.Libraries
{
    public abstract class DataLibrary<T> : ExternPointer<DataLibrary<T>.CacheData>
    {
        protected DataLibrary(IntPtr ptr, bool isOwner) : base(ptr, isOwner)
        {
        }

        public class CacheData
        {
            public Dictionary<string, T> ValueCache { get; } = new();
        }

        public abstract void Add(string key, T value);
        public abstract ulong Length { get; }

        protected abstract T? GetValueByKey(string key);

        public bool TryGetValue(string key, out T? value)
        {
            if (Cache.ValueCache.TryGetValue(key, out value) && value != null)
                return true;
            value = GetValueByKey(key);
            if (value != null)
            {
                Cache.ValueCache.Add(key, value);
            }

            return value != null;
        }

        public T this[string key]
        {
            get
            {
                if (!TryGetValue(key, out var value))
                    throw new KeyNotFoundException($"Value with key `{key}` was not found");
                return value!;
            }
        }

        protected override CacheData CreateCache() => new();
    }
}