///
/// Copyright (c) 2015-2016 Sensus Metering Systems
///
using System;
using log4net;
using TBF.Boxes;

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

		bool done;

		/// Set by the constructor
		BalanceDev balanceDev;
		DoubleBox tara;

		/// <summary>
		/// Events:  BalanceDone, Error
		/// </summary>
		/// <param name="balanceDev">Balance device instance</param>
		/// <param name="result">Reference to variable for 'tara' in kg</param>
		public TaringOp(BalanceDev balanceDev, ref DoubleBox tara)
		{
			if (balanceDev == null) throw new ArgumentNullException("balanceDev");
			this.balanceDev = balanceDev;

			this.tara = tara;

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

		/// <summary>Start this operation</summary>
		public void Start()
		{
			tara.Val = 0.0f;	// Don't do anything, tara = 0
			done = true;
		}

		/// <summary>Run this operation</summary>
		/// <returns>
		///		Event.None
		///		Event.BalanceDone
		///		Event.Error . . . . . Current.Tick == null
		/// </returns>
		public Event Run()
		{
			if (done) return Event.ScaleDone;			/// Taring has been done already

			if (balanceDev.MsrmntState == MsrmntState.Busy) return Event.Busy;

            if (balanceDev.MsrmntState == MsrmntState.Overload)
            {
                tara.Val = balanceDev.Capacity;
                done = true;
                return Event.ScaleOverload;
            }

            if (balanceDev.MsrmntState == MsrmntState.Valid)
			{
				tara.Val = balanceDev.Mass;
				done = true;
				return Event.ScaleDone;				/// Taring completed
			}

			return Event.Busy;
		}

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