#region

using System.Collections.Generic;
using System.Data;
using System.Windows.Forms;
using CSFrameworkV5.Core;

#endregion

namespace CSFrameworkV5.Business
{
    /// <summary>
    ///     数据字典的观察者清单
    /// </summary>
    public class DataDictObservers
    {
        private static List<IObserver> _Observers = new List<IObserver>();

        /// <summary>
        ///     增加观察者到队列
        /// </summary>
        /// <param name="observer">观察者</param>
        public static void Add(IObserver observer)
        {
            _Observers.Add(observer);
        }

        /// <summary>
        ///     通知观察者
        /// </summary>
        /// <param name="observerName">观察者名称</param>
        public static void Notify(string observerName)
        {
            foreach (var o in _Observers)
                if (o.Name == observerName)
                    o.Notify();
        }
    }

    /// <summary>
    ///     字典缓存数据的观察者基类。
    /// </summary>
    public class DataDictBaseObserver : IObserver
    {
        protected string _Name = "";
        protected object _ObservedData;

        public DataDictBaseObserver(string observerName, object observedData)
        {
            _Name = observerName;
            _ObservedData = observedData;
        }

        public string Name => _Name;

        public virtual void Notify()
        {
        }
    }

    /// <summary>
    ///     观察者模式使用例子
    /// </summary>
    public class ObserverSizeCombo : DataDictBaseObserver
    {
        private ComboBox.ObjectCollection _combo;

        public ObserverSizeCombo(string observerName,
            ComboBox.ObjectCollection combo, DataTable cachedData)
            : base(observerName, cachedData)
        {
            _combo = combo;
            DataDictObservers.Add(this);
        }

        public override void Notify()
        {
            var dt = _ObservedData as DataTable;

            _combo.Clear();
            foreach (DataRow row in dt.Rows) _combo.Add(row["SizeID"]);
        }
    }
}