///
/// Copyright (c) 2021 Sensus Slovensko a.s.
///
using System;
using System.Collections.Generic;
using log4net;
using TBF.BenchControl.ControlBoard.Uni;
using TBF.BenchControl.GenericDevices;
using TBF.Boxes;

namespace TBF.BenchControl.Uni.RegValve
{
	public class SetFlowOp : IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(SetFlowOp));
		public override string ToString()
		{
			return string.Format("SetFlowOp({0}, Qfrom={1}, Qto={2})", regV.Name, shrinkedTgtFlowLo, shrinkedTgtFlowHi);
		}

		/// Set by the constructor
        readonly UniCB cBoard;
        readonly RegValve regV;
		readonly int regulValveNr;
        readonly IFlowMeter flowMeter;
        readonly double shrinkedTgtFlowLo;
        readonly double shrinkedTgtFlowHi;
        readonly double targetFlowAve;
        readonly int timeout;
        readonly bool leaveMeasurementRunning;
        readonly bool reTryCommands;

        readonly double nominalFlow;
        readonly double maximalFlow;
        
        ///
        ///  Internal states of this operation
		///
		enum OpState
		{
			Idle = 0,
			ValveMoveToPosition1,			/// Wait 1 takt
			ValveMoveToPosition2,			/// This is actual move to position
			ValveMoveToPosition3,			/// Wait 1 takt
			CheckStatePosition,			    /// Verify
			SettingPosition,
			ValveMoveToFlow1,				/// Wait 1 takt
			ValveMoveToFlow2,				/// This is actual move to flow
			ValveMoveToFlow3,				/// Wait 1 takt
			CheckStateFlow,				    /// Verify
			SettingFlow,
			FlowReached,
			SendCommandAgain,
		}
		OpState opState;

        double currentReqFlowLo;
        double currentReqFlowHi;
		double targetPositionLo;
		double targetPositionHi;

        int startTime;
        int expireTime;
		DoubleBox flowBox;
        int flowWithinBoundsTime;

		
		/// <summary>
        /// Set required water flow. Conditionally leave the measurement running.
        /// Events:  FlowSet, FlowTimeOut
		/// </summary>
		/// <param name="cBoard">Control board device</param>
		/// <param name="regulValve">Regulation valve component</param>
        /// <param name="flowMeter">Flowmeter component</param>
		/// <param name="targetFlowLo">Lower limit of the flow to be achieved in [m3/h]</param>
		/// <param name="targetFlowHi">Upper limit of the flow to be achieved in [m3/h]</param>
		/// <param name="pidCoef">PID coefficient (float)</param>
		/// <param name="timeout">Timeout for the flow setting in [s]</param>
        /// <param name="leaveMeasurementRunning">true = Leave the measurement running after op. stop</param>
        /// <remarks>Only Elde.Valve flow are used, other flow on the lists are ignored</remarks>
        public SetFlowOp(UniCB cBoard, IRegValve regValve, IFlowMeter flowMeter, double targetFlowLo, double targetFlowHi,
                         DoubleBox flowBox, bool reTryCmds, int timeout, bool leaveMeasurementRunning)
        {
            this.cBoard = cBoard;
            if (this.cBoard == null) throw new ArgumentNullException("cBoard is null or not Uni");

            this.regV = regValve as RegValve;
            if (this.regV == null) throw new ArgumentNullException("regValve is null or not Uni");

            this.flowMeter = flowMeter;
            if (this.flowMeter == null) throw new ArgumentNullException("flowMeter");

            nominalFlow = flowMeter.NominalFlow;
            maximalFlow = nominalFlow * 1.25;

            this.targetFlowAve = (targetFlowLo + targetFlowHi) / 2;
            this.shrinkedTgtFlowLo = (0.7 * targetFlowLo) + (0.3 * this.targetFlowAve);   /// Move the lower limit 15% of the range up
            this.shrinkedTgtFlowHi = (0.7 * targetFlowHi) + (0.3 * this.targetFlowAve);   /// Move the upper limit 15% of the range down

            this.flowBox = flowBox;
            if (this.flowBox == null) throw new ArgumentNullException("flowBox");

            this.reTryCommands = reTryCmds;

            this.timeout = timeout;

            this.leaveMeasurementRunning = leaveMeasurementRunning;

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

        /// <summary>
        /// Set required water flow - Do not leave the measurement running.
        /// Events:  FlowSet
        /// </summary>
        public SetFlowOp(UniCB cBoard, IRegValve regValve, IFlowMeter flowMeter, double targetFlowLo, double targetFlowHi,
                         DoubleBox flowbox, bool reTryCmds, int timeout)
            : this(cBoard, regValve, flowMeter, targetFlowLo, targetFlowHi, flowbox, reTryCmds, timeout, false)
        {
        }

        /// <summary>
        /// Set required water flow - No timeout.
        /// Events:  FlowSet
        /// </summary>
        public SetFlowOp(UniCB cBoard, IRegValve regValve, IFlowMeter flowMeter, double targetFlowLo, double targetFlowHi,
                         DoubleBox flowbox, bool reTryCmds)
            : this(cBoard, regValve, flowMeter, targetFlowLo, targetFlowHi, flowbox, reTryCmds, int.MaxValue, false)
        {
        }

		/// <summary>
        /// Fetch target position limits from the dictionary or return false
		/// </summary>
        /// <param name="avgReqFlow">Average of the flow targer range (input)</param>
		/// <param name="positionLo">Target valve position low limit (output)</param>
		/// <param name="positionHi">Target valve position high limit (output)</param>
		/// <returns>true when positions for the target flow are stored in the memory, otherwise return false</returns>
        bool FetchTargetPosition(double avgReqFlow, out double positionLo, out double positionHi)
		{
            double targetPosition;
			if (regV.Dict.TryGetValue(avgReqFlow, out targetPosition))
			{
				positionLo = Math.Max(targetPosition * 0.95, 0.0);
				positionHi = Math.Min(targetPosition * 1.05, 100.0);
				return true;
			}
			else
			{
				positionLo = 0;
				positionHi = 0;
				return false;
			}
		}

        void StoreTargetPosition(double avgReqFlow, double actPosition)
		{
			if (!regV.Dict.ContainsKey(targetFlowAve))
			{
                regV.Dict.Add(new KeyValuePair<double, double>(avgReqFlow, actPosition));
			}
			return;
		}

		/// <summary>Start this operation</summary>
		public void Start()
        {
            startTime = StateMachine.Time;
            expireTime = StateMachine.Time + timeout;
            if (expireTime < 0) expireTime = int.MaxValue;

            double flowMtrFreq = flowMeter.ReadFrequency();
            double flow = flowMeter.ReadFlow();

            currentReqFlowLo = shrinkedTgtFlowLo;      /// Default lower limit
            currentReqFlowHi = shrinkedTgtFlowHi;      /// Default upper limit
            if (flow != 0)
            {
                flowBox.Val = flow;
                if (flow >= targetFlowAve) currentReqFlowHi = targetFlowAve;    /// Decrease upper limit
                if (flow <= targetFlowAve) currentReqFlowLo = targetFlowAve;    /// Increase lower limit
            }

            flowWithinBoundsTime = 0;

            if (regV.regValveCfg.StoredPositionReuse && FetchTargetPosition(targetFlowAve, out targetPositionLo, out targetPositionHi))
			{
                log.InfoFormat("SetFlowOp:Start() rv#={0} flowMtr#={1} TARGET: flowLo={2} flowHi={3} FETCHED: posLo={4} posHi={5}",
                                regulValveNr, flowMeter.Idx1, currentReqFlowLo, currentReqFlowHi, targetPositionLo, targetPositionHi);

				opState = OpState.ValveMoveToPosition1;
			}
			else
			{
                log.InfoFormat("SetFlowOp:Start() rv#={0} flowMtr#={1} TARGET: flowLo={2} flowHi={3}",
                                regulValveNr, flowMeter.Idx1, currentReqFlowLo, currentReqFlowHi);

				opState = OpState.ValveMoveToFlow1;
			}

            /// Start flow measurement
            regV.SendCommand(Command.Start, int.MaxValue, int.MaxValue, 0, 0);  /// TestMethods=0, StopDevs=0
		}

		/// <summary>Run this operation</summary>
		/// <returns>
        ///     Event.OpArgumentError
		///		Event.Starting
        ///		Event.Busy
        ///		Event.FlowReached
        ///		Event.RegulValveTimeOut
		/// </returns>
		public Event Run()
		{
            double rvPosition = regV.Position;
            double flowMtrFreq = flowMeter.ReadFrequency();
            double flow = flowMeter.ReadFlow();

            if (flow != 0)
            {
                flowBox.Val = flow;
            }

            log.InfoFormat("SetFlowOp:Run(T={0}) rv#={1} pos={2}% freq={3} flow={4} opState={5}",
                            StateMachine.Time - startTime, regulValveNr, rvPosition.ToString("F1"), flowMtrFreq, flow, opState);

            if (StateMachine.Time > expireTime)
            {
                return Event.RegulValveTimeOut;
            }
			else if (opState == OpState.SendCommandAgain)
			{
				flowWithinBoundsTime = 0;

				if (regV.regValveCfg.StoredPositionReuse && FetchTargetPosition(targetFlowAve, out targetPositionLo, out targetPositionHi))
				{
                    log.InfoFormat("Run(): rv#={0} flowMtr#={1} TARGET: flowLo={2} flowHi={3} FETCHED: posLo={4} posHi={5}",
                                    regulValveNr, flowMeter.Idx1, currentReqFlowLo, currentReqFlowHi, targetPositionLo, targetPositionHi);

					opState = OpState.ValveMoveToPosition1;
				}
				else
				{
                    log.InfoFormat("Run(): rv#={0} flowMtr#={1} TARGET: flowLo={2} flowHi={3}",
                                    regulValveNr, flowMeter.Idx1, currentReqFlowLo, currentReqFlowHi);

					opState = OpState.ValveMoveToFlow1;
				}

                /// Start flow measurement
                regV.SendCommand(Command.Start, int.MaxValue, int.MaxValue, 0, 0);  /// TestMethods=0, StopDevs=0
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToPosition1)
			{
				opState = OpState.ValveMoveToPosition2;
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToPosition2)	/// Move to position
			{
				/// Issues the appropriate ValveMove(...) command
				regV.MoveToPosition(targetPositionLo, targetPositionHi);

				opState = OpState.SettingPosition;
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToPosition3)
			{
                if (reTryCommands)
                {
                    opState = OpState.CheckStatePosition;
                }
                else
                {
                    opState = OpState.SettingPosition;
                }
				return Event.Starting;
			}
			else if (opState == OpState.CheckStatePosition)	/// Verify
			{
				if ((cBoard.State & (ulong)StatusP.TestWithRefFlowmtr) == 0)
				{
					opState = OpState.SendCommandAgain;
					return Event.Starting;
				}
				else if (regV.RegValveState != RegValveState.DacValueRegul)
				{
					/// Repeat appropriate ValveMove(...) command
                    regV.MoveToPosition(targetPositionLo, targetPositionHi);

                    log.InfoFormat("SetFlowOp: ValveMove({0}, Position, {1}, {2}, {3})",
                                    regulValveNr, targetPositionLo, targetPositionHi, regV.StableTime);

					opState = OpState.ValveMoveToPosition3;
					return Event.Starting;
				}
				else
				{
					opState = OpState.SettingPosition;
					return Event.Starting;
				}
			}
			else if (opState == OpState.SettingPosition)
			{
				/// Repeated untill position is reached
				if ((targetPositionLo <= rvPosition) && (rvPosition <= targetPositionHi))
				{
					opState = OpState.ValveMoveToFlow1;
				}
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToFlow1)
			{
				opState = OpState.ValveMoveToFlow2;
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToFlow2)	/// Move to flow
			{
				///
				/// Done once, issues an appropriate ValveMove(...) command
				///
                if ((currentReqFlowLo >= currentReqFlowHi) || (currentReqFlowLo > maximalFlow) || (currentReqFlowHi <= 0))
				{
					return Event.OpArgumentError;
				}

				log.InfoFormat("Run(): rv#={0} flowMtr#={1} TARGET: flowLo={2} flowHi={3}",
                                regulValveNr, flowMeter.Idx1, currentReqFlowLo, currentReqFlowHi);

				double freqLo = 2000.0 * currentReqFlowLo / nominalFlow;
				double freqHi = 2000.0 * currentReqFlowHi / nominalFlow;
				regV.SetFlow(flowMeter.Idx1,freqLo, freqHi);

				opState = OpState.ValveMoveToFlow3;
				return Event.Starting;
			}
			else if (opState == OpState.ValveMoveToFlow3)
			{
                if (reTryCommands)
                {
                    opState = OpState.CheckStateFlow;
                }
                else
                {
                    opState = OpState.SettingFlow;
                }
				return Event.Starting;
			}
			else if (opState == OpState.CheckStateFlow)       /// Verify the flow setting
			{
				if ( (cBoard.State & (ulong)StatusP.TestWithRefFlowmtr) == 0 ||
                     (regV.RegValveState & RegValveState.PwOrFreqRegul) != RegValveState.PwOrFreqRegul)
				{
					opState = OpState.SendCommandAgain;
					return Event.Starting;
				}
				else if (regV.RegValveState != RegValveState.PwOrFreqRegul)
				{
					/// Done once, issues an appropriate ValveMove(...) command
                    double freqLo = 2000.0 * currentReqFlowLo / nominalFlow;
                    double freqHi = 2000.0 * currentReqFlowHi / nominalFlow;
                    regV.SetFlow(flowMeter.Idx1, freqLo, freqHi);

                    log.InfoFormat("SetFlowOp: ValveMove({0}, Frequency, {1}, {2}, {3})",
                                    regulValveNr, freqLo, freqHi, regV.StableTime);

                    opState = OpState.ValveMoveToFlow3;
					return Event.Starting;
				}
				else
				{
					opState = OpState.SettingFlow;
					return Event.Busy;
				}
			}
			else if (opState == OpState.SettingFlow)
			{
				/// Regulation valve is setting flow to the required value

                if ((currentReqFlowLo <= flow) && (flow <= currentReqFlowHi))
				{
                    /// Flow is within range

                    if (flowWithinBoundsTime++ >= regV.FlowStableSec)
					{
                        /// Flow is within range for sufficiently long time

                        if (regV.regValveCfg.StoredPositionReuse)
						{
                            double storedPosition;
							if (regV.Dict.TryGetValue(targetFlowAve, out storedPosition))
							{
								/// update the stored valve position
								
                                StoreTargetPosition(targetFlowAve, (rvPosition + storedPosition) / 2.0);
								log.InfoFormat("Run(): rv#={0} reqFlow={1} pos={2}% stored={3} <--- Updating a stored position",
												regulValveNr, targetFlowAve, rvPosition.ToString("F1"), storedPosition);
							}
							else
							{
								/// store the valve position
								StoreTargetPosition(targetFlowAve, rvPosition);
								log.InfoFormat("Run(): rv#={0} reqFlow={1} pos={2}% <--- Storing a new position",
												regulValveNr, targetFlowAve, rvPosition.ToString("F1"));
							}
						}

						log.InfoFormat("flow = {0} m3/h (lo={1}, hi={2}, REACHED)", flow, currentReqFlowLo, currentReqFlowHi);

						opState = OpState.FlowReached;
						return Event.FlowReached;
					}
					else
					{
						log.InfoFormat("flow = {0} m3/h (lo={1}, hi={2}, FLOW_OK_TIMER={3}s)", flow, currentReqFlowLo, currentReqFlowHi, flowWithinBoundsTime);
						return Event.Busy;
					}
				}
				else if (StateMachine.Time > expireTime)
				{
					return Event.RegulValveTimeOut;
				}
				else
				{
					log.InfoFormat("flow = {0} m3/h (lo={1}, hi={2})", flow, currentReqFlowLo, currentReqFlowHi);
					flowWithinBoundsTime = 0;
					return Event.Busy;
				}
			}
			else /// opState == OpState.FlowReached
			{
				log.InfoFormat("flow = {0} m3/h (lo={1}, hi={2}, REACHED)", flow, currentReqFlowLo, currentReqFlowHi);
				return Event.FlowReached;
			}
		}

        /// <summary>Start this operation</summary>
        public void Stop()
		{
            if (!leaveMeasurementRunning)
            {
			    /// Stop measurement
                regV.SendCommand(Command.Stop, 50000, 50000, 0, StopDevs.RegValveRegulation);   /// TestMethods=0
            }

            opState = OpState.Idle;
        }
	}
}