///
/// Copyright (c) 2021 Sensus Slovensko a.s.
///
using System;
using log4net;
using TBF.Rig.GenericDevices;

namespace TBF.Rig.ControlBoard.Uni
{
	public class FlyingStartStopTestOp : IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(FlyingStartStopTestOp));
        public override string ToString() { return string.Format("FlyingStartStopTestOp()"); }

		/// Arguments of the constructor
		readonly UniCB uniCB;
        readonly TBF.Rig.Uni.RegValve.RegValve regV;
        readonly TBF.Rig.Uni.FlowMeter.FlowMeter flowMeter;
        readonly double qFrom;
        readonly double qTo;
		readonly int pulsesCount;   /// Number of reference pulses for a complete test

        /// <summary>
        /// Operation for a Flying start-stop test (constructor)
        /// 
        /// Events: OpArgumentError .... invalid arguments, test cannot be started
        ///         StartingTest ....... starting a test
        ///         TestInProgress ..... test was successfully started, test is running
        ///         TestCompleted ...... test was successfully completed
        ///         Error .............. unspecified error while running a test
        /// </summary>
        /// <param name="cb">Control board component</param>
		/// <param name="devices">Components used by the test</param>
        /// <param name="qFrom">Flow lower limit</param>
        /// <param name="qTo">Flow upper limit</param>
        /// <param name="pulsesCount">Test duration - number of reference flow meter pulses</param>
        public FlyingStartStopTestOp(UniCB cb, OutputPath devices, double qFrom, double qTo, int pulsesCount)
        {
            this.uniCB = cb;

			flowMeter = devices.FlowMeter as TBF.Rig.Uni.FlowMeter.FlowMeter;
            if (flowMeter == null) throw new ArgumentNullException("Invalid flow meter");

			regV = devices.RegValve as TBF.Rig.Uni.RegValve.RegValve;
            if (regV == null) throw new ArgumentNullException("Invalid regulation valve");

            this.qFrom = qFrom;
			this.qTo = qTo;
            this.pulsesCount = pulsesCount;

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

        ///  Internal state of this operation
        enum OpState
        {
            StartingTest,
            TestInProgress,
            TestCompleted,
        }

        OpState opState;

		/// <summary>
        /// Start this operation
        /// </summary>
		public void Start()
        {
            log.InfoFormat("Op.Start() RV#={0} Et#={1} Qfrom={2} Qto={3}", regV.Idx1, flowMeter.Idx1, qFrom, qTo);

            /// Start the test (and the flow measurement)
            uniCB.StartTest(false, flowMeter.Idx1, 0, 40, true, false, false, false, pulsesCount, 0);

            opState = OpState.StartingTest;
        }

		/// <summary>
        /// Run this operation
        /// </summary>
		/// <returns>
        ///   Event.OpArgumentError .... invalid arguments, test cannot be started
        ///   Event.StartingTest ....... starting a test
        ///   Event.TestInProgress ..... test was successfully started, test is running
        ///   Event.TestCompleted ...... test was successfully completed
        ///   Event.Error .............. unspecified error while running a test
        /// </returns>
		public Event Run()
		{
            log.DebugFormat("Op.Run() opState={0}", opState);

            switch (opState)
            {
                case OpState.StartingTest:

                    if (qFrom < 0 || qFrom >= qTo || qTo > 1.25 * flowMeter.NominalFlow)
                    {
                        return Event.OpArgumentError;   /// Invalid qFrom, qTo
                    }

                    if (!flowMeter.MsrmntAvailable ||                           /// Flow measurement not started yet
                        (uniCB.State & (ulong)StatusP.ReadingCounters) == 0 ||  /// Test was not started yet
                        uniCB.RefFrequency == 0)                                /// Measured flow is 0
                    {
                        return Event.StartingTest;  /// Flow regulation cannot be started
                    }

                    /// Start flow regulation
                    double reqFlowAve = (qFrom + qTo) / 2;
                    double reqFlowLo = (0.7 * qFrom) + (0.3 * reqFlowAve);  /// Move the lower limit 15% of the range up
                    double reqFlowHi = (0.7 * qTo) + (0.3 * reqFlowAve);    /// Move the upper limit 15% of the range down
                    /// 
                    uniCB.SetFlow(false, regV.Idx1, 2000 * reqFlowLo / flowMeter.NominalFlow,
                                                    2000 * reqFlowHi / flowMeter.NominalFlow);

                    opState = OpState.TestInProgress;
                    return Event.TestInProgress;

                case OpState.TestInProgress:

                    if ((uniCB.State & (ulong)StatusP.TestCompleted) == 0)
                    {
                        return Event.TestInProgress;    /// Test was not completed yet
                    }
                    opState = OpState.TestCompleted;
                    return Event.TestCompleted;

                case OpState.TestCompleted:
                default:
                    return Event.TestCompleted;
            }
		}

		/// <summary>
        /// Stop this operation
        /// </summary>
		public void Stop()
        {
            log.Info("Op.Stop()");
            uniCB.Stop(false);
        }
	}
}