/*

* 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.Collections.Generic;

using System.Text;

using CrashItemLib.Engine;

using CrashItemLib.Crash.InfoSW;

namespace CrashItemLib.Crash.Container

{

    sealed internal class CIContainerIndex : IEnumerable< KeyValuePair<uint, CIContainerCollection> >

    {

        #region Constructors

        public CIContainerIndex( CIEngine aEngine )

        {

            aEngine.CrashObservers += new CIEngine.CIEngineCrashObserver( Engine_CrashObserver );

        }

        #endregion

        #region API

        public CIContainerCollection DequeueNextContainer()

        {

            CIContainerCollection ret = null;

            //

            lock ( iDictionary )

            {

                Dictionary<uint, CIContainerCollection>.Enumerator enumerator = iDictionary.GetEnumerator();

                bool next = enumerator.MoveNext();

                if ( next )

                {

                    ret = enumerator.Current.Value;

                    iDictionary.Remove( enumerator.Current.Key );

                }

            }

            //

            return ret;

        }

        public static uint GetRomChecksum( CIContainer aContainer )

        {

            uint ret = 0;

            // Find the infosw item in order to obtain the image checksum

            CIInfoSW infoSW = aContainer.ChildByType( typeof( CIInfoSW ) ) as CIInfoSW;

            if ( infoSW != null )

            {

                ret = infoSW.ImageCheckSum;

            }

            return ret;

        }

        #endregion

        #region Properties

        public int Count

        {

            get { return iDictionary.Count; }

        }

        #endregion

        #region Event handlers

        private void Engine_CrashObserver( CIEngine.TCrashEvent aEvent, CIContainer aContainer )

        {

            if ( aEvent == CIEngine.TCrashEvent.EEventCrashRemovedAll )

            {

                lock ( iDictionary )

                {

                    iDictionary.Clear();

                }

            }

            else if ( aEvent == CIEngine.TCrashEvent.EEventCrashRemoved )

            {

                RemoveFromDictionary( aContainer );

            }

            else if ( aEvent == CIEngine.TCrashEvent.EEventCrashAdded )

            {

                AddToDictionary( aContainer );

            }

        }

        #endregion

        #region Internal methods

        private void RemoveFromDictionary( CIContainer aContainer )

        {

            uint checksum = GetRomChecksum( aContainer );

            CIContainerCollection collection = null;

            //

            lock ( iDictionary )

            {

                if ( iDictionary.TryGetValue( checksum, out collection ) )

                {

                    collection.Remove( aContainer );

                    // If the collection is empty, remove the mapping also

                    if ( collection.Count == 0 )

                    {

                        iDictionary.Remove( checksum );

                    }

                }

            }

        }

        private void AddToDictionary( CIContainer aContainer )

        {

            uint checksum = GetRomChecksum( aContainer );

            // Check if there is a collection for this key already

            CIContainerCollection collection = null;

            lock ( iDictionary )

            {

                if ( iDictionary.TryGetValue( checksum, out collection ) == false )

                {

                    // Nope, collection not yet registers

                    collection = new CIContainerCollection();

                    iDictionary.Add( checksum, collection );

                }

            }

            // Now save

            collection.Add( aContainer );

        }

        #endregion

        #region From IEnumerable< KeyValuePair<uint, CIContainerCollection> >

        public IEnumerator<KeyValuePair<uint,CIContainerCollection>> GetEnumerator()

        {

            foreach( KeyValuePair<uint,CIContainerCollection> kvp in iDictionary )

            {

                yield return kvp;

            }

        }

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()

        {

            foreach( KeyValuePair<uint,CIContainerCollection> kvp in iDictionary )

            {

                yield return kvp;

            }

        }

        #endregion

        #region Data members

        private Dictionary<uint, CIContainerCollection> iDictionary = new Dictionary<uint, CIContainerCollection>();

        #endregion

    }

}