using System;
using System.Collections.Generic;

namespace Framework
{
    public class ObjectPool<T>
    {
        private readonly Stack<T> _stack = new Stack<T>();
        private readonly Func<T> _createFunc;
        private readonly Action<T> _resetAction;
        private readonly Action<T> _destroyAction;

        public ObjectPool(Func<T> createFunc, Action<T> resetAction = null, Action<T> destroyAction = null, int initCount = 0)
        {
            _createFunc = createFunc;
            _resetAction = resetAction;
            _destroyAction = destroyAction;

            for (var i = 0; i < initCount; i++)
            {
                _stack.Push(_createFunc());
            }
        }

        public T Get()
        {
            return _stack.Count == 0 ? _createFunc() : _stack.Pop();
        }

        public void Release(T element)
        {
            _resetAction?.Invoke(element);

            _stack.Push(element);
        }

        public void Destroy()
        {
            if (_destroyAction != null)
            {
                foreach (var element in _stack)
                {
                    _destroyAction(element);
                }
            }

            _stack.Clear();
        }
    }
}