using System;
using System.Messaging;

namespace HMI.Simple.Util
{
    public class MSMQHelper : IDisposable
    {
        /// <summary>
        /// 消息队列名称
        /// </summary>
        private string msmqName = string.Empty;

        /// <summary>
        /// 消息队列路径
        /// </summary>
        private string msmqPath = string.Empty;

        /// <summary>
        /// 要操作的消息队列
        /// </summary>
        private MessageQueue msgQueue = null;

        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="Name">消息队列名称</param>
        public MSMQHelper(string Name)
        {
            try
            {
                this.msmqName = Name;
                this.msmqPath = ".\\private$\\" + this.msmqName;
                if (MessageQueue.Exists(this.msmqPath))
                {
                    // 如果当前消息队列已经存在
                    this.msgQueue = new MessageQueue(this.msmqPath);
                }
                else
                {
                    // 如果消息队列不存在，则创建消息对垒
                    this.msgQueue = MessageQueue.Create(this.msmqPath);
                }
                this.msgQueue.Formatter = new XmlMessageFormatter(new Type[] { typeof(string) });
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>
        /// 发送消息
        /// </summary>
        /// <param name="MessageID">消息ID</param>
        /// <param name="MsgString">要发送的字符串</param>
        public void Send(string MessageID, string MsgString)
        {
            try
            {
                this.msgQueue.Send(MsgString, MessageID);
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>
        /// 接收消息队列中的消息
        /// </summary>
        /// <param name="TimeOut">超时时间(ms)</param>
        /// <param name="MessageID">消息ID</param>
        /// <param name="MsgString">消息内容</param>
        public void Receive(long TimeOut, out string MessageID, out string MsgString)
        {
            try
            {
                MessageID = string.Empty;
                MsgString = string.Empty;
                TimeSpan Time = new TimeSpan(TimeOut);
                Message MsgReceived = null;
                try
                {
                    MsgReceived = this.msgQueue.Receive(Time);
                }
                catch
                {
                    // do nothing
                }

                if (MsgReceived != null)
                {
                    MessageID = MsgReceived.Label;
                    MsgString = MsgReceived.Body.ToString();
                }
            }
            catch (Exception ex)
            {
                throw new Exception("接收消息失败:" + ex.Message);
            }
        }

        /// <summary>
        /// 清除消息队列中的消息
        /// </summary>
        public void Clear()
        {
            try
            {
                this.msgQueue.Purge();
            }
            catch (Exception ex)
            {
                throw new Exception("清除消息队列失败:" + ex.Message);
            }
        }

        /// <summary>
        /// 关闭当前队列
        /// </summary>
        public void Close()
        {
            this.msgQueue.Close();
        }

        /// <summary>
        /// 删除当前队列
        /// </summary>
        public void Delete()
        {
            MessageQueue.Delete(this.msmqPath);
        }

        public void Dispose()
        {
            this.Close();
        }
    }
}