using System.Collections.Generic;

/// <summary>
/// 对象池，用于获取和回收常用对象，避免每次都创建一个新的
/// </summary>
public static class ObjectPool
{
    private static Dictionary<string, Stack<IPoolItem>> _pool = new Dictionary<string, Stack<IPoolItem>>();

    /// <summary>
    /// 回收一个对象
    /// </summary>
    public static void Reclaim(IPoolItem poolItem)
    {
        if (poolItem.IsRecycled)
        {
            return;
        }
        var logotype = poolItem.Logotype;
        if (!_pool.TryGetValue(logotype, out var poolItems))
        {
            poolItems = new Stack<IPoolItem>();
            _pool.Add(logotype, poolItems);
        }

        poolItems.Push(poolItem);
        poolItem.IsRecycled = true;
        poolItem.OnReclaim();
    }

    /// <summary>
    /// 根据标识从池中取出一个实例，如果没有该标识类型的实例，则返回null
    /// </summary>
    public static IPoolItem GetItem(string logotype)
    {
        if (_pool.TryGetValue(logotype, out var poolItems))
        {
            if (poolItems.Count > 0)
            {
                var poolItem = poolItems.Pop();
                poolItem.IsRecycled = false;
                poolItem.OnLeavePool();
                return poolItem;
            }
        }

        return null;
    }
    
    /// <summary>
    /// 根据标识从池中取出一个实例，如果没有该标识类型的实例，则返回null
    /// </summary>
    public static T GetItem<T>(string logotype) where T : IPoolItem
    {
        return (T)GetItem(logotype);
    }

    /// <summary>
    /// 销毁所有池中的物体
    /// </summary>
    public static void DisposeAllItem()
    {
        foreach (var keyValuePair in _pool)
        {
            var poolItems = keyValuePair.Value;
            while (poolItems.Count > 0)
            {
                var item = poolItems.Pop();
                item.Destroy();
            }
        }
        _pool.Clear();
    }
}