#region  --------------- Copyright Dresser Wayne Pignone -------------
/*
 * $Log: /Wrk/WayneLibraries/Wrk/StateEngine/StateEntry.cs $
 * 
 * 3     08-03-25 14:00 Mattias.larsson
 * Clean-up.
 * 
 * 2     08-02-26 14:08 Mattias.larsson
 * Renamed TargetStateName to TargetStateFactoryName.
 */
#endregion
#region Old file header
/*===============================================================================
 * StateEntry
 * 
 * Change history
 * When         Who     Comment
 * ----------   ------  ------------------------------------
 * 2006-07-18   RMa     Renamed TargetState -> TargetStateName.
 * 2005-12-05   RMa     This header added.
 * 
---------------------------------------------------------------------------------*/

#endregion
using System;
using System.Text;

namespace Wayne.Lib.StateEngine
{
	/// <summary>
	/// StateEntry contains information about the entry of a state.
    /// It is produced by the state transition lookup. The application
    /// receives it as an in parameter to the State.Enter() method.
    /// What is of intrest to the application might be the sourceTransition, and the
    /// attached source Event object.
	/// </summary>
	public class StateEntry
	{
		#region Fields

		private Transition sourceTransition;
		private string targetStateFactoryName;
        private HistoryType historyType;

		#endregion

		#region Construction

        /// <summary>
        /// Constructor for StateEntry
        /// </summary>
        /// <param name="sourceTransition">The transition that resulted in the state change.</param>
        /// <param name="targetStateFactoryName">The new state that is entered.</param>
        /// <param name="historyType">History type that should be used when entering a composite state.</param>
        public StateEntry(Transition sourceTransition, string targetStateFactoryName, HistoryType historyType)
        {
            this.sourceTransition = sourceTransition;
            this.targetStateFactoryName = targetStateFactoryName;
            this.historyType = historyType;
        }

		#endregion

		#region Properties

        /// <summary>
        /// The transition that resulted in the state change.
        /// </summary>
		public Transition SourceTransition
		{
			get { return sourceTransition; }
		}

        /// <summary>
        /// The new state that is entered.
        /// </summary>
		public string TargetStateFactoryName
		{
			get { return targetStateFactoryName; }
		}

        /// <summary>
        /// History type that should be used when entering a composite state.
        /// </summary>
		public HistoryType HistoryType
		{
			get { return historyType; }
		}

		#endregion	

        /// <summary>
        /// Returns state information from the State entry.
        /// </summary>
        /// <returns></returns>
        public string GetStateInformation()
        {
            var stringBuilder = new StringBuilder();
            if (SourceTransition != null)
            {
                if (SourceTransition.Sender != null)
                    stringBuilder.Append(string.Format("Came from: {0}.", SourceTransition.Sender.FactoryName));                    

                if (SourceTransition.SourceEvent != null)
                    stringBuilder.Append(string.Format("Triggered by: {0}.", SourceTransition.Sender));                    

                ExceptionTransition exceptionTransition = SourceTransition as ExceptionTransition;
                if (exceptionTransition != null)
                {
                    stringBuilder.Append(string.Format("Exception thrown: {0}.", exceptionTransition.Exception));                    
                }
            }
            return stringBuilder.ToString();
        }
	}
}