/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

* 

* Description:

*

*/

using System;

using System.IO;

using System.Collections;

using System.Collections.Generic;

using System.Text;

using SymbianUtils;

using CrashItemLib.PluginAPI;

using CrashItemLib.Crash.Source;

using CrashItemLib.Crash.Container;

namespace CrashItemLib.Engine.Sources.Types

{

    internal sealed class CIEngineSourceReaderTrace : CIEngineSourceReader

    {

        #region Constructors

        public CIEngineSourceReaderTrace( CIEngineSource aSource, CFFSource[] aPluginSources )

            : base( aSource )

		{

            iPluginSources.AddRange( aPluginSources );

        }

        #endregion

        #region From CIEngineSourceReader

        public override CIEngineSource.TState Read()

        {

            CIEngineSource.TState ret = CIEngineSource.TState.EStateReadyCorrupt;

            // Listen to container creation events in all plugin reader objects

            foreach ( CFFSource source in iPluginSources )

            {

                CFFReader reader = source.Reader;

                reader.Observer += new CFFReader.ReaderObserver( CFFReader_Observer );

                reader.ExceptionHandler += new CFFReader.ReaderExceptionHandler( CFFReader_ExceptionHandler );

            }

            //

            try

            {

                CIEngineTraceReader traceReader = new CIEngineTraceReader( this );

                traceReader.Read( TSynchronicity.ESynchronous );

            }

            finally

            {

                ret = CalculateFinalState();

                // Stop listening to container creation events in all plugin reader objects

                foreach ( CFFSource source in iPluginSources )

                {

                    CFFReader reader = source.Reader;

                    reader.Observer -= new CFFReader.ReaderObserver( CFFReader_Observer );

                    reader.ExceptionHandler -= new CFFReader.ReaderExceptionHandler( CFFReader_ExceptionHandler );

                }

            }

            //

            return ret;

        }

        public override CFFSource.TReaderOperationType OpType

        {

            get { return CFFSource.TReaderOperationType.EReaderOpTypeTrace; }

        }

        #endregion

        #region API

        #endregion

        #region Event handlers

        private void CFFReader_Observer( CFFReader.TEvent aEvent, CFFReader aReader, object aContext )

        {

            base.Trace( "[CIEngineSourceReaderTrace] CFFReader_Observer() - START - aEvent: " + aEvent + ", file: " + base.Source.FileName );

            // This method is called for both native and trace based events

            if ( aEvent == CFFReader.TEvent.EReadingContainerCreated )

            {

                CIContainer container = aContext as CIContainer;

                if ( container != null )

                {

                    base.SaveCrash( container );

                }

            }

            else if ( aEvent == CFFReader.TEvent.EReadingProgress )

            {

                int progress = ( aContext != null && aContext is int ) ? (int) aContext : 0;

                base.Source.OnSourceReadingProgress( progress );

            }

            base.Trace( "[CIEngineSourceReaderTrace] CFFReader_Observer() - END - aEvent: " + aEvent + ", file: " + base.Source.FileName );

        }

        private void CFFReader_ExceptionHandler( Exception aException, CFFReader aReader )

        {

            base.AddException( aException );

        }

        #endregion

        #region Multiplexing methods

        internal void OnTraceReadInit()

        {

            lock ( iPluginSources )

            {

                foreach ( CFFSource entry in iPluginSources )

                {

                    entry.Reader.OnTraceReadInit();

                }

            }

        }

        internal void OnTraceReadComplete()

        {

            lock ( iPluginSources )

            {

                foreach ( CFFSource entry in iPluginSources )

                {

                    entry.Reader.OnTraceReadComplete();

                }

            }

        }

        internal void OnTraceReadOffer( CFFTraceLine aLine )

        {

            lock ( iPluginSources )

            {

                foreach ( CFFSource entry in iPluginSources )

                {

                    CFFTraceLine line = new CFFTraceLine( aLine.Line, aLine.LineNumber, entry );

                    entry.Reader.OnTraceReadOffer( line );

                }

            }

        }

        internal void OnTraceReadException( Exception aException )

        {

            base.AddException( aException );

        }

        internal void OnTraceReaderProgress( int aProgress )

        {

            base.Source.OnSourceReadingProgress( aProgress );

        }

        #endregion

        #region Internal methods

        private CIEngineSource.TState CalculateFinalState()

        {

            CIEngineSource.TState ret = CIEngineSource.TState.EStateReadyCorrupt;

            // For trace-based operations we'll potentially be firing each trace

            // line at multiple readers, in which case we only mark the file as

            // corrupt if no readers completed successfully.

            int countCorrupt = 0;

            int countReady = 0;

            int countContainers = base.CrashItemCount;

            // Count number of ready vs corrupt readers

            foreach ( CFFSource source in iPluginSources )

            {

                CFFReader reader = source.Reader;

                CFFReader.TState readerState = reader.State;

                //

                switch ( readerState )

                {

                case CFFReader.TState.EStateCorrupt:

                    ++countCorrupt;

                    break;

                case CFFReader.TState.EStateReady:

                    ++countReady;

                    break;

                default:

                case CFFReader.TState.EStateProcessing:

                case CFFReader.TState.EStateUninitialised:

                    SymbianUtils.SymDebug.SymDebugger.Assert( false );

                    break;

                }

            }

            // If we created at least one container, then we did still manage to create

            // some kind of crash output irrespective of how many of the readers indicated 

            // the source was corrupt. In that case, the underlying source file is treated

            // as valid.

            base.Trace( "[CIEngineSourceReaderTrace] CalculateFinalState() - total: {0}, ready: {1}, corrupt: {2}", countContainers, countReady, countCorrupt );

            if ( countContainers > 0 )

            {

                ret = CIEngineSource.TState.EStateReady;

            }

            else

            {

                // We didn't manage to create any crash items at all from this source

                // file.

                if ( countCorrupt > 0 )

                {

                    // At least one reader indicated that the source file was corrupt, 

                    // and since no other reader could create any kind of valid output

                    // we'll treat the source file as entirely corrupt.

                    ret = CIEngineSource.TState.EStateReadyCorrupt;

                }

                else

                {

                    // No crash container created, but nobody said the file was corrupt

                    // either. It's just a "no items" file.

                    ret = CIEngineSource.TState.EStateReadyNoItems;

                }

            }

            base.Trace( "[CIEngineSourceReaderTrace] CalculateFinalState() - END - ret: {0}, file: {1}", ret, base.Source.FileName );

            return ret;

        }

        #endregion

        #region Internal class - actual trace file reader

        internal class CIEngineTraceReader : AsyncTextFileReader

        {

            #region Constructors

            public CIEngineTraceReader( CIEngineSourceReaderTrace aMultiplexer )

                : base( aMultiplexer.Source.FileName )

            {

                iMultiplexer = aMultiplexer;

            }

            #endregion

            #region API

            public void Read( TSynchronicity aSynchronicity )

            {

                base.StartRead( aSynchronicity );

            }

            #endregion

            #region From AsyncTextFileReader

            protected override void HandleReadStarted()

            {

                try

                {

                    base.HandleReadStarted();

                }

                finally

                {

                    iMultiplexer.OnTraceReadInit();

                }

            }

            protected override void HandleReadCompleted()

            {

                try

                {

                    base.HandleReadCompleted();

                }

                finally

                {

                    iMultiplexer.OnTraceReadComplete();

                }

            }

            protected override void HandleFilteredLine( string aLine )

            {

                CFFTraceLine line = new CFFTraceLine( aLine, LineNumber, null );

                iMultiplexer.OnTraceReadOffer( line );

            }

            protected override void HandleReadException( Exception aException )

            {

                try

                {

                    base.HandleReadException( aException );

                }

                finally

                {

                    iMultiplexer.OnTraceReadException( aException );

                }

            }

            protected override void OnProgressChanged( int aProgress )

            {

                iMultiplexer.OnTraceReaderProgress( aProgress );

            }

            #endregion

            #region Data members

            private readonly CIEngineSourceReaderTrace iMultiplexer;

            #endregion

        }

        #endregion

        #region Data members

        private List<CFFSource> iPluginSources = new List<CFFSource>();

        #endregion

    }

}