using Autodesk.Revit.UI;

namespace FWindSoft.Revit
{
    /*
     * 验证是否是同步，不是同步的话，则需要提供回调函数
     */
    /// <summary>
    /// 扩展事件
    /// </summary>
    public class ExternalEventCommand
    {
        public ExternalEventCommand(RevitHandler handler) : this(handler, true)
        {
        }

        public ExternalEventCommand(RevitHandler handler, bool createRefCommand)
        {
            Handler = handler;
            if (createRefCommand)
            {
                CreateEvent();
            }
        }

        /// <summary>
        /// 命令实际处理者
        /// </summary>
        public RevitHandler Handler { get; private set; }

        /// <summary>
        /// 生成Event
        /// </summary>
        /// <returns></returns>
        public ExternalEvent CreateEvent()
        {
            if (Handler != null && Event == null)
            {
                Event = ExternalEvent.Create(Handler);
            }

            return Event;
        }

        #region 关联扩展事件

        /// <summary>
        /// 扩展事件的命令
        /// </summary>
        public ExternalEvent Event { get; private set; }

        /// <summary>
        /// 触发命令
        /// </summary>
        /// <returns></returns>
        public ExternalEventRequest Raise()
        {
            #region 如果关联命令为空，创建一次

            if (Event == null)
            {
                CreateEvent();
            }

            #endregion

            if (Event == null)
            {
                return ExternalEventRequest.Pending;
            }

            return Event.Raise();
        }

        /// <summary>
        /// 根据指定参数触发命令
        /// </summary>
        /// <param name="parameter">传入参数，在回调方法参数中可以找打使用</param>
        /// <returns></returns>
        public ExternalEventRequest Raise(object parameter)
        {
            if (Handler != null)
            {
                Handler.Parameter = parameter;
            }

            #region 如果关联命令为空，创建一次

            if (Event == null)
            {
                CreateEvent();
            }

            #endregion

            if (Event == null)
            {
                return ExternalEventRequest.Pending;
            }

            return Event.Raise();
        }

        #endregion

        #region 析构处理

        ~ExternalEventCommand()
        {
            if (Event != null)
                Event.Dispose();
        }

        #endregion
    }
}