///
/// Copyright (c) 2021-2022 Sensus Slovensko a.s.
///
using System;
using System.Collections.Generic;
using log4net;
using TBF.Rig.ControlBoard.Uni;
using TBF.Rig.GenericDevices;

namespace TBF.Rig.Uni.RegValveLowRegulTimeSaturation
{
	public class SetRegValvePositionOp : IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(SetRegValvePositionOp));
		public override string ToString()
		{
            return string.Format("SetRegValvePositionOp({0},{1},{2})", regV.Name, posLoPct, posHiPct);
		}

		///
		///  Internal states of this operation
		///
		enum OpState
		{
			Idle = 0,
			MoveToPosition,		/// Send commend to move to position
			CheckState,			/// Check RV state by reading statos word
			MovingToPosition,	/// Command passed OK, RV is moving to a position
		}
		OpState opState;

		/// Set by the constructor
		readonly UniCB uniCB;
		readonly RegValve regV;
		readonly int regValveNr;
        readonly double posLoPct;
        readonly double posHiPct;
        readonly int timeout;

        ///  Process values
        int expireTime;
		bool positionReached;

		/// <summary>
        /// Set required water flow.
        /// Events:  FlowSet, FlowTimeOut
		/// </summary>
		/// <param name="uniCB">Control board device</param>
		/// <param name="_regulValve">Regulation valve component</param>
		/// <param name="posLoPct">Lower limit of the position to be achieved</param>
		/// <param name="posHiPct">Upper limit of the position to be achieved</param>
		/// <param name="timeout">Timeout in sec. for setting the flow</param>
		/// <remarks>Only Elde.Valve flow are used, other flow on the lists are ignored</remarks>
        public SetRegValvePositionOp(UniCB uniCB, RegValve regV, double posLoPct, double posHiPct, int timeout)
        {
            this.uniCB = uniCB;
            if (this.uniCB == null) throw new ArgumentNullException("ctrlBoard");

            this.regV = regV as RegValve;
            if (this.regV == null) throw new ArgumentNullException("regValve is null or not Uni");
            this.regValveNr = this.regV.Idx1;

			this.posLoPct = posLoPct;
            this.posHiPct = posHiPct;
            this.timeout = timeout;
			
			log.Debug(this.ToString());
        }

        /// <summary>
        /// Set required water flow - no timeout.
        /// Events:  FlowSet
        /// </summary>
        public SetRegValvePositionOp(UniCB cBoard, RegValve regValve, float posLoPct, float posHiPct)
            : this(cBoard, regValve, posLoPct, posHiPct, int.MaxValue)
        {
        }

		/// <summary>Start this operation</summary>
		public void Start()
        {
            positionReached = false;
            expireTime = StateMachine.Time + timeout;
            log.InfoFormat("Start(): {0} reqPosLo={1}%, reqPosHi={2}%", regV.Name, posLoPct.ToString("F1"), posHiPct.ToString("F1"));
			opState = OpState.MoveToPosition;
        }

		/// <summary>
        /// Run this operation
        /// </summary>
		/// <returns>
		///		Event.None  . . . . . . . busy adjusting position
		///		Event.PositionReached . . position reached
		///		Event.OpArgumentError . . invalid required position
		/// </returns>
		public Event Run()
		{
			if (opState == OpState.MoveToPosition)
            {
                if (posLoPct >= posHiPct || posLoPct > 100.0 || posHiPct < 0)
                {
					return Event.OpArgumentError;
                }

                regV.MoveToPosition(false, posLoPct, posHiPct);
                opState = OpState.CheckState;
                log.WarnFormat("Run(): RV#={0}, state={1}, MoveToPosition(false, {2:D1}, {3:D1}) issued", regValveNr, opState, posLoPct, posHiPct);
                return Event.None;
            }

			if (positionReached) return Event.PositionReached;

			double positionPct = regV.Position;
            log.WarnFormat("Run(): RV#={0}, state={1}, pos={2}%", regValveNr, opState, positionPct.ToString("F1"));

			if (opState == OpState.CheckState)
			{
				if (posLoPct <= positionPct && positionPct <= posHiPct)
				{
					positionReached = true;
					return Event.PositionReached;
				}
				else if (regV.RegValveState != RegValveState.DacValueRegul)
				{
					opState = OpState.MoveToPosition;		/// Resend move command again in the next run
					return Event.None;
				}
				else
				{
					opState = OpState.MovingToPosition;
					return Event.None;
				}
			}
			else if (StateMachine.Time > expireTime)
			{
				return Event.RegulValveTimeOut;
			}
			else if (opState == OpState.MovingToPosition)
			{
				if (posLoPct <= positionPct && positionPct <= posHiPct)
				{
					positionReached = true;
					return Event.PositionReached;
				}
				return Event.None;
			}
			return Event.None;
		}

        /// <summary>Stop this operation</summary>
        public void Stop()
		{
        }
	}
}