/*

* Copyright (c) 2004-2008 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 System.IO;

using SymbianUtils;

using SymbianUtils.Range;

using SymbianUtils.Tracer;

using SymbianUtils.FileTypes;

using SymbianStructuresLib.Debug.Symbols;

using SymbianStructuresLib.CodeSegments;

using SymbianSymbolLib.DbgEnginePlugin;

using SymbianSymbolLib.SourceManagement.Source;

using SymbianSymbolLib.QueryAPI;

namespace SymbianSymbolLib.Relocator

{

    internal class SymbolRelocator : IEnumerable<SymSourceAndCollection>

    {

        #region Constructors

        public SymbolRelocator( SymbolPlugin aPlugin )

		{

            iPlugin = aPlugin;

		}

		#endregion

        #region API

        public SymbolCollection Activate( CodeSegDefinition aCodeSegment )

        {

            SymbolCollection ret = null;

            // Find the corresponding code seg

            SymSourceAndCollection pair = SourceManager[ aCodeSegment ];

            if ( pair != null  )

            {

                SymbolCollection col = pair.Collection;

                lock ( col.SyncRoot )

                {

                    if ( col.IsFixed )

                    {

                        // Cannot activate a fixed code segment - TODO: should this return "true", i.e. already activated?

                    }

                    else

                    {

                        bool safe = CheckSafeToActivate( aCodeSegment );

                        if ( safe )

                        {

                            // Deep copy the collection

                            SymbolCollection dupe = SymbolCollection.NewCopy( iPlugin.ProvisioningManager.IdAllocator, col );

                            // Set new process-specific relocated base address

                            dupe.Relocate( aCodeSegment.Base );

                            // Save so that we can unload it later

                            pair = new SymSourceAndCollection( pair, dupe );

                            AddToActivationList( pair, aCodeSegment );

                            // We managed to activate a binary, so return the collection

                            ret = dupe;

                            iPlugin.Trace( "[S] ACTIVATE - {0}", aCodeSegment );

                        }

                    }

                }

            }

            //

            return ret;

        }

        public bool Deactivate( CodeSegDefinition aCodeSegment )

        {

            bool activated = iActivationLUT.ContainsKey( aCodeSegment );

            if ( activated )

            {

                SymSourceAndCollection pair = iActivationLUT[ aCodeSegment ];

                //

                lock ( iActivatedCollections )

                {

                    iActivatedCollections.Remove( pair.Collection );

                }

                lock ( iActivationLUT )

                {

                    iActivationLUT.Remove( aCodeSegment );

                }

                //

                iPlugin.Trace( "[S] DEACTIVATE - {0} @ {1}", pair.Collection.FileName, aCodeSegment );

            }

            //

            return activated;

        }

        #endregion

		#region Properties

        public SymbolCollectionList CollectionList

        {

            get { return iActivatedCollections; }

        }

        public int Count

        {

            get

            {

                lock ( iActivatedCollections )

                {

                    lock ( iActivationLUT )

                    {

                        System.Diagnostics.Debug.Assert( iActivatedCollections.Count == iActivationLUT.Count );

                        return iActivationLUT.Count;

                    }

                }

            }

        }

        #endregion

        #region Internal methods

        internal SymbolPlugin Plugin

        {

            get { return iPlugin; }

        }

        internal SymSourceManager SourceManager

        {

            get { return Plugin.SourceManager; }

        }

        private void AddToActivationList( SymSourceAndCollection aEntry, CodeSegDefinition aCodeSegment )

        {

            lock ( iActivatedCollections )

            {

                iActivatedCollections.AddAndBuildCache( aEntry.Collection );

            }

            lock ( iActivationLUT )

            {

                iActivationLUT.Add( aCodeSegment, aEntry );

            }

        }

        private bool CheckSafeToActivate( CodeSegDefinition aCodeSegment )

        {

            lock ( iActivationLUT )

            {

                bool alreadyExists = iActivationLUT.ContainsKey( aCodeSegment );

                if ( alreadyExists )

                {

                    // Specified code segment already activated

                    return false;

                }

                else

                {

                    // We must check that there's no overlap in activation ranges between code segments.

                    foreach ( KeyValuePair<CodeSegDefinition, SymSourceAndCollection> kvp in iActivationLUT )

                    {

                        AddressRange range = kvp.Key;

                        if ( range.Contains( aCodeSegment ) )

                        {

                            // Overlaps with existing activated code segment

                            return false;

                        }

                    }

                }

                //

                return true;

            }

        }

        #endregion

        #region From IEnumerable<SymSourceAndCollection>

        public IEnumerator<SymSourceAndCollection> GetEnumerator()

        {

            foreach ( KeyValuePair<CodeSegDefinition, SymSourceAndCollection> kvp in iActivationLUT )

            {

                yield return kvp.Value;

            }

        }

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

        {

            foreach ( KeyValuePair<CodeSegDefinition, SymSourceAndCollection> kvp in iActivationLUT )

            {

                yield return kvp.Value;

            }

        }

        #endregion

        #region Data members

        private readonly SymbolPlugin iPlugin;

        private SymbolCollectionList iActivatedCollections = new SymbolCollectionList();

        private Dictionary<CodeSegDefinition, SymSourceAndCollection> iActivationLUT = new Dictionary<CodeSegDefinition, SymSourceAndCollection>();

        #endregion

    }

}