using System.Collections.Concurrent;

namespace YLErp.Modules.TradeRiskCalcModule.TaskRunner
{
    /// <summary>
    /// [线程安全]交易扩展数据源
    /// </summary>
    class TradeExtendDataSource<TData> : ITradeExtendUpdater where TData : TradeExtendBase
    {
        readonly Guid _eventGuid;
        readonly ConcurrentDictionary<int, TData> _dic;

        private TradeExtendDataSource()
        {
            _dic = new ConcurrentDictionary<int, TData>();
            _eventGuid = Events.EventBus.Subscribe<OtcTradeUpdateEvent>(t =>
            {
                UpdateData(t.TradeIds);
            });
        }

        ~TradeExtendDataSource()
        {
            Events.EventBus.Unsubscribe(_eventGuid);
        }

        /// <summary>
        /// 清空缓存
        /// </summary>
        public void Clear()
        {
            _dic.Clear();
        }

        /// <summary>
        /// 获取数据
        /// </summary>
        public TData GetData(int tradId)
        {
            if (!_dic.TryGetValue(tradId, out var data))
            {
                var table = DbContextFactory.GetYLDbContext().Set<TData>();
                data = table.FirstOrDefault(n => n.TradeId == tradId);
                if (data != null)
                {
                    _dic.AddOrUpdate(tradId, data, (k, t) => data);
                }
            }
            return data;
        }

        /// <summary>
        /// 跟随trade更新
        /// </summary>
        public void UpdateData(IEnumerable<int> tradeIds)
        {
            if (_dic.Count > 1000)
            {
                _dic.Clear();
                return;
            }

            if (tradeIds == null || !tradeIds.Any())
            {
                return;
            }

            foreach (var tradId in tradeIds)
            {
                _dic.TryRemove(tradId, out _);
            }
        }

        /// <summary>
        /// 使用这个主要是偷个懒
        /// </summary>
        public static readonly TradeExtendDataSource<TData> Default;

        static TradeExtendDataSource()
        {
            Default = new TradeExtendDataSource<TData>();
        }
    }
}