// Copyright (c) 2007-2010 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:
// Trace Core
//

#ifndef __TRACECOREMEDIAWRITER_H__
#define __TRACECOREMEDIAWRITER_H__


// Include files
#include "TraceCoreWriter.h"


// Forward declarations
class DTraceCoreMediaIf;
class TMediaWriterStatistics;


/**
 * Properties of a single trace
 */
class TTraceBuffer
    {
public:
    TTraceBuffer* iNext;
    TUint8* iBuffer;
    TUint16 iLength;
    TUint16 iMissedBefore;
    TUint8 iType;
    };


/**
 * Writer implementation, which uses the media interface to write data
 */
class DTraceCoreMediaWriter : public DTraceCoreWriter
    {
public:
    
    /**
     * Constructor
     */
    IMPORT_C DTraceCoreMediaWriter();
    
    /**
     * Destructor
     */
    IMPORT_C ~DTraceCoreMediaWriter();
    
    /**
     * Registers this writer to TraceCore
     */
    IMPORT_C TInt Register();
    
    /**
     * Gets the number of traces allowed per second
     */
    virtual TInt GetTraceFrequency() = 0;
    
    /**
     * Initializes a trace buffer
     * 
     * @param aType the entry type
     * @param aBuffer the buffer
     */
    virtual void StartBuffer( TWriterEntryType aType, TTraceBuffer& aBuffer ) = 0;
    
    /**
     * Finishes a trace buffer
     * 
     * @param aBuffer the buffer
     */
    virtual void EndBuffer( TTraceBuffer& aBuffer ) = 0;
    
private:

    /**
     * Starts an entry
     *
     * @return the entry ID that is passed to other Write-functions
     */
    IMPORT_C TUint32 WriteStart( TWriterEntryType aType );

    /**
     * Ends an entry
     *
     * @param aEntryId the entry ID returned by WriteStart
     */
    IMPORT_C void WriteEnd( TUint32 aEntryId );

    /**
     * Writes 8-bit data to given entry
     * 
     * @param aEntryId the entry ID returned by WriteStart
     * @param aData the trace data
     */
    IMPORT_C void WriteData( TUint32 aEntryId, TUint8 aData );

    /**
     * Writes 16-bit data to given entry
     * 
     * @param aEntryId the entry ID returned by WriteStart
     * @param aData the trace data
     */
    IMPORT_C void WriteData( TUint32 aEntryId, TUint16 aData );

    /**
     * Writes 32-bit data to given entry
     * 
     * @param aEntryId the entry ID returned by WriteStart
     * @param aData the trace data
     */
    IMPORT_C void WriteData( TUint32 aEntryId, TUint32 aData );
	
    /**
     * Timer which enques the send DFC
     * 
     * @param aMediaWriter the media writer
     */
    static void SendTimerCallback( TAny* aMediaWriter );
    
    /**
     * Called from the static timer callback function
     */
    void SendTimerCallback();
    
	/**
	 * DFC for sending data
     * 
     * @param aMediaWriter the media writer
	 */
	static void SendDfc( TAny* aMediaWriter );
    
    /**
     * Called from the static function to send data
     */
    void SendDfc();
    
    /**
     * Initializes the statistics
     */
    TBool InitStatistics();
    
    /**
     * Blocks the current thread for a while
     * 
     * @param aType the context type from NThread::UserContextType
     */
    void Block( TInt aType );
    
private:
	
	/**
	 * Media interface for sending data
	 */
    DTraceCoreMediaIf* iMediaIf;
	
	/**
	 * DFC for sending data
	 */
	TDfc iSendDfc;
	
    /**
     * Timer which is used to send traces
     */
    TTickLink iSendTimer;
    
    /**
     * Flags which tells if the timer is active or not
     */
    TBool iSendTimerActive;
    
    /**
     * Pointer to the list of free trace buffers
     */
    TTraceBuffer* iFirstFreeBuffer;
    
    /**
     * Pointer to the next trace to be sent
     */
    TTraceBuffer* iFirstReadyBuffer;
    
    /**
     * Pointer to the end of list where new traces are added
     */
    TTraceBuffer* iLastReadyBuffer;
    
    /**
     * All trace buffers
     */
    TTraceBuffer* iTraceBuffers;

    /**
     * Number of free buffers
     */
    TUint32 iFreeBuffers;
    
    /**
     * Thread which sends data
     */
    NThread* iSenderThread;

    /**
     * Timestamp of the last trace sent
     */
    TUint32 iLastTraceSent;
    
    /**
     * Media writer statistics
     */
    TMediaWriterStatistics* iStatistics;
    
    /**
     * Number of FastCounter ticks between traces
     */
    TInt iFastCounterBetweenTraces;
    };

#endif

// End of file