--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mpx/playbackframework/playbackengine/src/mpxplaybackcommandbuffer.cpp	Thu Dec 17 08:55:47 2009 +0200
@@ -0,0 +1,281 @@
+/*
+* Copyright (c) 2006 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:  Buffer commands
+*
+*/
+
+
+#include"mpxplaybackcommandbuffer.h"
+#include "mpxlog.h"
+
+// ============================== MEMBER FUNCTIONS ============================
+
+
+// ----------------------------------------------------------------------------
+// Two-phased constructor
+// ----------------------------------------------------------------------------
+//
+CMPXPlaybackCmdBuffer* CMPXPlaybackCmdBuffer::NewL(
+    MMPXPlaybackCmdBufferObserver& aObserver)
+    {
+    CMPXPlaybackCmdBuffer* h=new(ELeave)CMPXPlaybackCmdBuffer(aObserver);
+    CleanupStack::PushL(h);
+    h->ConstructL();
+    CleanupStack::Pop(h);
+    return h;
+    }
+
+// ----------------------------------------------------------------------------
+// C++ constructor can NOT contain any code that might leave.
+// ----------------------------------------------------------------------------
+//
+CMPXPlaybackCmdBuffer::CMPXPlaybackCmdBuffer(
+    MMPXPlaybackCmdBufferObserver& aObserver)
+:   CTimer(EPriorityStandard),
+    iObserver(aObserver)
+    {
+    CActiveScheduler::Add(this);
+    }
+
+
+// ----------------------------------------------------------------------------
+// Is this a command controlled by command buffer
+// ----------------------------------------------------------------------------
+//
+TBool CMPXPlaybackCmdBuffer::CommandForBuffering(TMPXPlaybackCommand aCmd) const
+    {
+    switch(aCmd)
+        {
+        case EPbCmdPlay:
+        case EPbCmdStop:
+        case EPbCmdPause:
+        case EPbCmdPlayPause:
+        case EPbCmdNext:
+        case EPbCmdPrevious:
+            return ETrue;
+        default:
+            return EFalse;
+        }
+    }
+
+// ----------------------------------------------------------------------------
+// Handle time out event
+// ----------------------------------------------------------------------------
+//
+void CMPXPlaybackCmdBuffer::RunL()
+    {
+    MPX_DEBUG1("CMPXPlaybackCmdBuffer::RunL() entering");
+
+    if (!iEventProcessing && IsCommandBuffered())
+    //
+    // Client is not currently processing any events, and there are new
+    // events to deliver
+    //
+        {
+        if (iEvent.iNavKeyBuffered)
+            {
+            iObserver.HandleCmdBufferSkipEventL( EPbsSkipEventEnd ); // notify end skip event
+            }
+        iIsCommandBuffered=EFalse;
+        iEventProcessing=ETrue; // Handled by client
+        iObserver.HandleCmdBufferEventL(iEvent);
+        }
+
+    MPX_DEBUG1("CMPXPlaybackCmdBuffer::RunL() exiting");
+    }
+
+// ----------------------------------------------------------------------------
+// Handle leave in command handling
+// ----------------------------------------------------------------------------
+//
+TInt CMPXPlaybackCmdBuffer::RunError(TInt /*aError*/)
+    {
+    MPX_DEBUG1("==>CMPXPlaybackCmdBuffer::RunL()");
+    ClearCommands();
+    iEventProcessing=EFalse;
+    MPX_DEBUG1("<==CMPXPlaybackCmdBuffer::RunL()");
+    return KErrNone;
+    }
+
+// ----------------------------------------------------------------------------
+// Buffer a playback/skip command, along with the current state and position in
+// the track. Update playback state/position internally. When time-out, restore
+// state/position to playback engine.
+// ----------------------------------------------------------------------------
+//
+void CMPXPlaybackCmdBuffer::BufferCommandL(TMPXPlaybackCommand aCmd,
+                                           TMPXPlaybackState aState,
+                                           TInt aPos)
+    {
+    MPX_DEBUG4("CMPXPlaybackCmdBuffer::BufferCommandL(%d, %d, %d) entering", aCmd, aState, aPos);
+
+    if (!CommandForBuffering(aCmd) ||
+        (aCmd==EPbCmdPlay && aState==EPbStatePlaying) ||
+        (aCmd==EPbCmdPause && aState==EPbStatePaused))
+        {
+        // This command does not change any state, so make sure
+        // to negate any previous commands
+        ClearCommands();
+        return;
+        }
+
+    TBool saveIsCmdBuffered = iIsCommandBuffered;
+    iBufferTime = KPbMediaKeyIntervalMicroSeconds;
+    const TInt KPbMediaKeyNoIntervalMicroSeconds=10;  // 0.00001s
+    const TInt KPbMediaKeySkipIntervalMicroSeconds=200000;  // 0.2s or 200ms
+    const TInt KPbMediaKeyPauseIntervalMicroSeconds=100000;  // 0.1s or 100ms
+    Cancel(); // Stop timer and wait again for any other events
+
+    if (!iIsCommandBuffered)
+        {
+        iIsCommandBuffered=ETrue;
+        iEvent.iTrackOffset=0;
+        iEvent.iState=aState;
+        iEvent.iNavKeyBuffered=EFalse;
+        }
+
+    if (!iEvent.iNavKeyBuffered)
+        {
+        iEvent.iPos = aPos;
+        }
+
+    switch(aCmd)
+        {
+        case EPbCmdNext:
+            {
+            iEvent.iTrackOffset++;
+            iEvent.iNavKeyBuffered++;
+            TBool savedStatus( iEventProcessing );
+            iEventProcessing = ETrue;
+            iObserver.HandleCmdBufferSkipEventL( EPbsSkipEventNext ); // notify skip event
+            iEventProcessing = savedStatus;
+			if ( !saveIsCmdBuffered )
+				{
+				iBufferTime = KPbMediaKeySkipIntervalMicroSeconds; // 0.2s or 200ms
+				}
+            break;
+            }
+        case EPbCmdPrevious:
+            {
+            if (!iEvent.iNavKeyBuffered &&
+                (aState==EPbStatePlaying || aState==EPbStatePaused) &&
+                 iEvent.iPos > KPbReplayThresholdMiliSeconds)
+                {
+                MPX_DEBUG1("CMPXPlaybackCmdBuffer::BufferCommandL() Setting position 0");
+                aPos=0;
+                }
+            else
+                {
+                TBool savedStatus( iEventProcessing );
+                iEventProcessing = ETrue;
+                iObserver.HandleCmdBufferSkipEventL( EPbsSkipEventPrevious ); // notify skip event
+                iEventProcessing = savedStatus;
+                iEvent.iTrackOffset--;
+                }
+            iEvent.iNavKeyBuffered++;
+            break;
+            }
+        case EPbCmdPlay:
+            iEvent.iState = EPbStatePlaying;
+            if ( !saveIsCmdBuffered )
+                {
+                iBufferTime = KPbMediaKeyNoIntervalMicroSeconds;
+                }
+            break;
+        case EPbCmdPause: // From play to pause
+            if (EPbStatePlaying == iEvent.iState)
+                {
+                iEvent.iState = EPbStatePaused;
+				if ( !saveIsCmdBuffered )
+					{
+					iBufferTime = KPbMediaKeyPauseIntervalMicroSeconds;
+					}
+                }
+             break;
+        case EPbCmdPlayPause:
+            {
+            if ( EPbStatePlaying == iEvent.iState )
+                {
+                iEvent.iState = EPbStatePaused;
+				if ( !saveIsCmdBuffered )
+					{
+					iBufferTime = KPbMediaKeyPauseIntervalMicroSeconds;
+					}
+				break;
+                }
+            else
+                {
+                iEvent.iState = EPbStatePlaying;
+                if ( !saveIsCmdBuffered )
+                    {
+                    iBufferTime = KPbMediaKeyNoIntervalMicroSeconds;
+                    }
+                }
+            break;
+            }
+        case EPbCmdStop:
+            iEvent.iState = EPbStateStopped;
+            break;
+        default:
+            break;
+        }
+    // maintain pos unless track has changed
+    iEvent.iPos=iEvent.iTrackOffset ? 0 : aPos;
+    //
+    if (!iEventProcessing) // If client isn't processing event
+        {
+        After(iBufferTime);
+        }
+
+    MPX_DEBUG1("CMPXPlaybackCmdBuffer::BufferCommandL() exiting");
+    }
+
+// ----------------------------------------------------------------------------
+// Called by client when finished processing commands in buffer
+// ----------------------------------------------------------------------------
+//
+void CMPXPlaybackCmdBuffer::CompleteCommand()
+    {
+    MPX_DEBUG1("CMPXPlaybackCmdBuffer::CompleteCommand() entering");
+
+    iEventProcessing=EFalse; // Client finished processing event
+    if (IsCommandBuffered() && !IsActive())
+        {
+        After(iBufferTime);
+        }
+
+    MPX_DEBUG1("CMPXPlaybackCmdBuffer::CompleteCommand() exiting");
+    }
+
+// ----------------------------------------------------------------------------
+// Check if any commands buffered
+// ----------------------------------------------------------------------------
+//
+TBool CMPXPlaybackCmdBuffer::IsCommandBuffered() const
+    {
+    return iIsCommandBuffered;
+    }
+
+// ----------------------------------------------------------------------------
+// Clear all commands
+// ----------------------------------------------------------------------------
+//
+void CMPXPlaybackCmdBuffer::ClearCommands()
+    {
+    iIsCommandBuffered=EFalse;
+    Cancel();
+    }
+
+
+