///
/// Copyright (c) 2013-2015 Sensus Metering Systems
///
using System;
using log4net;

namespace TBF.BenchControl.Elde
{
	public class StopPreviousOp : IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(StopPreviousOp));
		public override string ToString() { return string.Format("StopPreviousOp(.)"); }

		/// Set by the constructor
		readonly ControlBoardDev controlBoard;

		///
        ///  Internal states of this operation
		///
		enum OpState
		{
			Idle = 0,
			CheckIfStopped,
            ResendCommand,
            Stopped,
		}
		OpState opState;

		/// <summary>
        /// Stop the previous control board operation (diverter, gate, etc.)
		/// Events:  None or PreviousStopped
		/// </summary>
        /// <param name="controlBoardDev">Control board component reference</param>
        public StopPreviousOp(ControlBoardDev controlBoardDev)
        {
			if (controlBoardDev == null) throw new ArgumentNullException("controlBoardDev");
			this.controlBoard = controlBoardDev;

			log.Debug(this.ToString());
        }


        void SendStopCommand()
        {
            controlBoard.SendCommand(Command.Stop, 0, 0, 0, TestMethods.Diverter,
                                     StopDevs.Diverter | StopDevs.GatePulse | StopDevs.Reference | StopDevs.RegValveRegulation);
        }


		/// <summary>Start this operation</summary>
		public void Start()
        {
            SendStopCommand();
			opState = OpState.CheckIfStopped;
        }


		/// <summary>Run this operation</summary>
		/// <returns>
		///		Event.None or Event.PreviousStopped
		/// </returns>
		public Event Run()
		{
			if (opState == OpState.CheckIfStopped)
			{
				if ((controlBoard.StatusP & (StatusP.TestCompleted | StatusP.TestInProgress)) == 0)
				{
					opState = OpState.Stopped;
					return Event.PreviousStopped;
				}
                else
                {
                    opState = OpState.ResendCommand;
                    return Event.None;
                }
			}
            else if (opState == OpState.ResendCommand)
            {
                if ((controlBoard.StatusP & (StatusP.TestCompleted | StatusP.TestInProgress)) == 0)
                {
                    opState = OpState.Stopped;
                    return Event.PreviousStopped;
                }
                else
                {
                    SendStopCommand();
                    opState = OpState.CheckIfStopped;
                    return Event.None;
                }
            }
            else if (opState == OpState.Stopped)
			{
				return Event.PreviousStopped;
			}

			return Event.None;
		}


		/// <summary>Stop this operation</summary>
		public void Stop()
		{
			opState = OpState.Idle;
		}
	}
}