///
/// Copyright (c) 2013-2016 Sensus Metering Systems
///
using System;
using System.Collections.Generic;
using log4net;
using TBF.Boxes;

namespace TBF.BenchControl.Elde.RegisterReader
{
	public class RegisterReader : ComponentBase, GenericDevices.IRegisterReader, IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(RegisterReader));
        public override string ToString() { return string.Format("RegisterReader({0})", Cfg.ToString(1)); }

        readonly RegisterReaderCfg registerReaderCfg;

		public int Position { get { return registerReaderCfg.Position; } }		/// 1 .. inf
																				/// 
		public double PulsesPerLtr { get { return (double)registerReaderCfg.ProcParams.PulsesPerLtr; } }
		public double LtrsPerPulse { get { return (PulsesPerLtr <= float.Epsilon) ? 1.0 : (1 / PulsesPerLtr); ; } }

		public int WMPulses { get { return wmPulses; } }
		public int WMRefPulses { get { return wmRefPulses; } }
		public double WMVolume { get { return LtrsPerPulse * (double)wmPulses; } }

		int wmPulses;
		int wmRefPulses;

		/// <summary> This is to cope with counter overflow </summary>
		int lastPulses;
		bool lastPulsesValid;

		readonly ControlBoardDev controlBoard;


		public RegisterReader()
		{
			Clear();
		}

		public RegisterReader(Generic.IComponentCfg cfg, IList<Generic.IComponent> components)
			: base(cfg)
		{
			registerReaderCfg = cfg as RegisterReaderCfg;

			controlBoard = (ControlBoardDev)TbfComponents.FindComponent(cfg.ParentName, components);
			if (controlBoard == null) throw new Exception("Cannot find " + Name + " parent");

			/// Prepare data for SendCalibData() control board component method

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

		public void Clear()
		{
			wmPulses = 0;
			wmRefPulses = 0;
			lastPulsesValid = false;
		}

		public void TestCompleted()
		{
			ReadPulses();
		}

		/// <summary>
		/// Events:  Event.ReadRegisterDone, Event.Error
		/// </summary>
		/// <returns>ReadWaterMeter instance reference casted to IOperaton</returns>
		public IOperation ReadRegisterOp()
		{
			return this;
		}

		private void ReadPulses()
		{
			if (!lastPulsesValid)
			{
				lastPulses = (int)controlBoard.WMeterPulses(Position);
				lastPulsesValid = true;
			}
			else
			{
				UInt16 lowerWord = controlBoard.WMeterPulses(Position);
				int uncorrected = (int)(((uint)lastPulses & 0xFFFF0000) | lowerWord);
				if (Math.Abs(uncorrected - lastPulses) <= Int16.MaxValue)
				{
					lastPulses = uncorrected;
				}
				else if (Math.Abs(uncorrected + 65536 - lastPulses) <= Int16.MaxValue)
				{
					lastPulses = uncorrected + 65536;
				}
				else if (Math.Abs(uncorrected - 65536 - lastPulses) <= Int16.MaxValue)
				{
					lastPulses = uncorrected - 65536;
				}
			}

			wmPulses = lastPulses;
			wmRefPulses = (int)controlBoard.EtPulses(Position);

            log.DebugFormat("Register={0}  WM={1}  Reference={2}  Not-gated-ref={3}", Name, wmPulses, wmRefPulses, (int)controlBoard.EtPulses(0));
		}

		/// <summary>Start this operation</summary>
		public void Start()
		{
			lastPulsesValid = false;
			ReadPulses();
		}

		/// <summary>Run this operation</summary>
		/// <returns>eventDone</returns>
		public Event Run()
		{
			ReadPulses();
			return Event.ReadRegisterDone;
		}

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