///
/// Copyright (c) 2013-2015 Sensus Metering Systems
/// Author: Milan Hanajik
///
using System;
using log4net;
using TBF.Boxes;

namespace TBF.BenchControl.MettlerToledo.Standard
{
	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;
        FloatBox 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 FloatBox 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()
		{
			log.DebugFormat("{0} - Start()", balanceDev.Name);
			done = false;
			balanceDev.Taring();
		}

		/// <summary>Run this operation</summary>
		/// <returns>
		///		Event.None
		///		Event.BalanceDone
		///		Event.Error . . . . . Current.Tick == null
		/// </returns>
		public Event Run()
		{
			if (done) return Event.BalanceDone;			/// 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.BalanceOverload;
            }

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

			balanceDev.Taring();	/// Failed -> repeat taring
			return Event.Busy;
		}

		/// <summary>Stop this operation</summary>
		public void Stop()
		{
			log.DebugFormat("{0} - Stop()", balanceDev.Name);
		}
	}
}