/*

* Copyright (c) 2006-2007 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: Header of IRLogoDownloadEngine.cpp

*

*/

#ifndef IRLOGODOWNLOADENGINE_H

#define IRLOGODOWNLOADENGINE_H

#include <mhttpdatasupplier.h>

#include <mhttptransactioncallback.h>

#include <rhttptransaction.h>

#include <rhttpsession.h>

#include <rhttpheaders.h>

#include <http.h>

#include <es_sock.h>

#include "irisdspreset.h"

#include "mlogodownloadobserver.h"

#include "ircacheobserver.h"

#include "iractivenetworkobserver.h"

//Used to specify the maximum header-field value length

const TInt KMAXHEADERLENGTHS = 255;

//Forward Declarations

class RHTTPSession;

class RHTTPTransaction;

class CIRIsdsPreset;

class CIRNetworkController;

class MLogoDownloadObserver;

class CIRCacheMgmt; //for logo cache mgmt

class CIRHttpResponseData;

class MIRActiveNetworkObserver;//for network up and downs

/**

 * class CIRLogoDownlaodEngine

 */

class CIRLogoDownloadEngine : public CBase,

                              public MHTTPTransactionCallback,

                              public MHTTPDataSupplier,

                              public MIRCacheObserver,

                              public MIRActiveNetworkObserver

    {

public:

    /**

     * enum TState

     * status of the transaction

     */

   	enum TState

        {   

        EIdle,

        ESendingEvent

        };

    /**

     * CIRLogoDownloadEngine* NewL()

     * Creates instance of CIRLogoDownloadEngine.

     */

    IMPORT_C static CIRLogoDownloadEngine* NewL();

    /**

     * SendRequestL(CIRIsdsPreset* aPreset)

     * API is called from the SearchResultsView for to download logo

     */

    IMPORT_C void SendRequestL( CIRIsdsPreset* aPreset, TInt aXValue = 0,

                                TInt aYValue = 0 );

    /**

     * SendRequestL()

     * API is called from the NowPlayingView for to download logo 

     */

    IMPORT_C void SendRequestL( CIRIsdsPreset* aPreset,

                    MLogoDownloadObserver* aLogoHandle, TInt aNPVReq = 1,

                    TInt aXValue = 0, TInt aYValue = 0 );

    /**

     * IsLogoCachedL()

     * 

     */

    IMPORT_C TBool IsLogoCachedL( CIRIsdsPreset* aPreset, TInt aXValue = 0,

                    TInt aYValue = 0 );

    /**

     * CancelTransaction()

     * cancels the current transaction

     */

    IMPORT_C void CancelTransaction();

    /**

     * TBool IsRunning() const

     * To know the status of downloading logo

     */

    IMPORT_C TBool IsRunning() const;

    /**

     * ~CIRLogoDownloadEngine()

     * Destructs instance of CIRLogoDownloadEngine

     */

    IMPORT_C ~CIRLogoDownloadEngine();

    /**

     * void SendPresetWithLogoL()

     * sends the preset with logo to the requestors

     */

    IMPORT_C void SendPresetWithLogoL();

    /**

     * GetCacheLogoL(TDesC& aUrl,TInt& aStatus)

     * takes the url as a parameter and returns the logo data which is in cache

     * this API is called form the search results for to display logo on the view

     */

    IMPORT_C void GetCacheLogoL( const TDesC& aUrl, TInt& aStatus );

    /**

     * TDesC8& SendCacheLogo()

     * sends the logo which is cached

     */

    IMPORT_C TDesC8& SendCacheLogo();

    /**

     * void FetchLogoDataL(CIRIsdsPreset* aPreset)

     * API is used to download logo from isds/internet

     * called in the API SendRequestL(CIRIsdsPreset* aPreset)

     */

    void FetchLogoDataL( CIRIsdsPreset* aPreset );

    /**

     * void FetchLogoDataL()

     * API is used to download logo from isds/internet

     * called in the API SendRequestL()

     */

    void FetchLogoDataL( CIRIsdsPreset* aPreset,

                         MLogoDownloadObserver* aLogoHandle, TInt aNPVReq );

    /**

     * void ManagePresetArrayIndexL()

     * To update the iPresetArray current index

     */

    void ManagePresetArrayIndexL();

    /**

     * void ManageCachePresetArrayIndexL()

     * To update the iCachePresetArray current index

     */

    void ManageCachePresetArrayIndexL();

    /**

     * void CacheError()

     * Called from cachemgmt in case of an error

     * callback API from MIRCacheObserver

     */

    void CacheError();

    /**

     * void CacheFailed()

     * Called from cachemgmt in case of cache failure

     * callback API from MIRCacheObserver

     */

    void CacheFailed();

    /**

     * void CacheInvalid()

     * Called from cachemgmt in case cache is invalid

     * callback API from MIRCacheObserver

     */

    void CacheInvalid();

    /**

     * void CachedStructureL()

     * Called from cachemgmt data retrival is successful

     *@param aChoice,it gives the data type of the cache

     * callback API from MIRCacheObserver

     */

    void CachedStructureL( TInt aChoice );

    /**

     *  ReleaseResources();

     *  Releases the resources held by logo download engine

     */

    void ReleaseResources();

	//from MIRActiveNetworkObserver

	/**

	 * Notified by network controller when network is active

	 * to reissue the request  

	 * NotifyActiveNetworkObserversL()

	 */	

	 void NotifyActiveNetworkObserversL(TIRNetworkEvent aEvent);

    /**

     * Notifies all observers whose network request is active

     * to reset the pending request status  

     * ResetPendingRequests()

     */

    void ResetPendingRequests( TBool aValue );

private:

    /**

     * void ConstructL()

     * 2nd phase construction

     */

    void ConstructL();

    /**

     * CIRLogoDownloadEngine()

     * Standard C++ constructor

     */

    CIRLogoDownloadEngine();

    /**

     * void SetHeaderL(RHTTPHeaders aHeaders, TInt aHdrField, const TDesC8& aHdrValue) const

     * to set the headers of the http transaction

     */

    void SetHeaderL( RHTTPHeaders aHeaders, TInt aHdrField,

                     const TDesC8& aHdrValue ) const;

    /**

     * void IssueLogoDownloadRequest()

     * submits the transaction for to download the logo

     */

    void IssueLogoDownloadRequestL();

    /**

     * void CheckCacheForLogoL()

     * checks the logo in the cache

     */

    void CheckCacheForLogoL( TInt aValue );

    /**

     * void MHFRunL()

     * from MHTTPTransactionCallback

     */

    void MHFRunL( RHTTPTransaction aTransaction, const THTTPEvent& aEvent );

    /**

     * TInt MHFRunError()

     * //from MHTTPTransactionCallback

     */

    TInt MHFRunError( TInt aError, RHTTPTransaction aTransaction,

                      const THTTPEvent& aEvent );

    /**

     * void ReleaseData()

     * from MHTTPDataSupplier

     */

    void ReleaseData();

    /**

     * TBool GetNextDataPart()

     * from MHTTPDataSupplier

     */

    TBool GetNextDataPart( TPtrC8& aDataPart );

    /**

     * TInt Reset()

     * from MHTTPDataSupplier

     */

    TInt Reset();

    /**

     * TInt OverallDataSize()

     * from MHTTPDataSupplier

     */

    TInt OverallDataSize();

    /**

     *  CIRLogoDownloadEngine::ExtractResponseHeadersL()

     *  Used to Extract the response headers.

     *  @param aTransaction HTTP Transaction object

     */

    void ExtractResponseHeadersL( const RHTTPTransaction& aTransaction );

    /**

     *  CIRLogoDownloadEngine::HttpHeaderReceived()

     *  indicate that an HTTP header is received.

     *  @param aHeaderData Reference to the Header Info

     */

    virtual void HttpHeaderReceived( const TDesC8 &aHeaderData );

    /**

     * CIRLogoDownloadEngine::ExtractHeaderValue()

     * Used to build the CIRHttpResponseData

     */

    void ExtractHeaderValue( const TDesC8& aHeaderData,

                    const TDesC8& aHeaderName, const TDesC8& aDelimeter,

                    TDes8& aHolder ) const;

    /**

     * CIRLogoDownloadEngine::HttpDateHeaderReceived()

     * Used to build the CIRHttpResponseData members

     */

    void HttpDateHeaderReceived( const TDesC8 &aHeader, const TTime& aTime );

private:

    /**

     * pointer to the logo observer object

     */

    MLogoDownloadObserver* iLogoHandle;

    /**

     * pointer to the logo observer object

     */

    MLogoDownloadObserver* iTempLogoHandle;

    /**

     * pointer to the logo observer object

     */

    MLogoDownloadObserver* iCacheTempLogoHandle;

    /**

     * pointer to the preset object

     * temporary preset in the logo downloading usecase

     */

    CIRIsdsPreset* iTempPreset;

    /**

     * pointer to the preset object

     * temporary preset in the cache checking usecase

     */

    CIRIsdsPreset* iCacheTempPreset;

    /**

     * pointer to the preset object

     * preset used to conver CIRPreset to CIRIsdsPreset

     */

    CIRIsdsPreset* iCopyPreset;

    /**

     * Network controller handle pointer

     */

    CIRNetworkController *iIRNetworkControllerHandle;

    /**

     * Preset Array for downloading logo

     */

    CArrayPtrFlat<CIRIsdsPreset>* iPresetArray;

    /**

     * Preset Array for checking cache

     */

    CArrayPtrFlat<CIRIsdsPreset>* iCachePresetArray;

    /**

     * MLogoDownloadObserver array for downloading logo

     */

    CArrayPtrFlat<MLogoDownloadObserver>* iObserverArray;

    /**

     * MLogoDownloadObserver array for checking cache

     */

    CArrayPtrFlat<MLogoDownloadObserver>* iCacheObserverArray;

    /**

     * To keep track whether the req came for Favorites or NPV(downloading logo)

     */

    CArrayFixFlat<TInt>* iReqFromArray;

    /**

     * To keep track whether the req came for Favorites or NPV(checking cache)

     */

    CArrayFixFlat<TInt>* iCacheReqFromArray;

    /**

     * Separate session for the logo downloading

     */

    RHTTPSession iLogoSession;

    /**

     * http transaction

     */

    RHTTPTransaction iTransaction;

    /**

     * for the transactions with cache mgmt

     */

    CIRCacheMgmt *iCache;

    /**

     * Pointer to Response header data

     */

    CIRHttpResponseData* iResponseHeaders;

    /**

     * boolean for to know the status of the downloading logo

     */

    TBool iRunning;

    /**

     * body of the transaction request

     */

    TDesC8* iReqBody;

    /**

     * body of the transaction response

     */

    HBufC8* iRespBody;

    /**

     * size of the response body

     */

    TInt iRespBodySize;

    /**

     * state of the transaction

     */

    TState iState;

    /**

     * status, from which the preset has modified

     */

    TBool iPresetModifiedStatus;

    /**

     * iPresetArray position

     */

    TInt iPresetArrayPos;

    /**

     * position of the iReqFromArray

     */

    TInt iReqFromArrayPos;

    /**

     * position of the iObserverArray

     */

    TInt iObserverArrayPos;

    /**

     * position of the iCachePresetArray

     */

    TInt iCachePresetArrayPos;

    /**

     * position of the iCacheReqFromArray

     */

    TInt iCacheReqFromArrayPos;

    /**

     * position of the iCacheObserverArray

     */

    TInt iCacheObserverArrayPos;

    /**

     * status of cache request

     */

    TInt iCacheReqFrom;

    /**

     * temporary variable for the status of request

     */

    TInt iTempReqFrom;

    /**

     * boolean to verify first time or not

     */

    TBool iFirstTime;

    /**

     * ETrue if logo is available in cache

     */

    TBool iLogoCached;

    /**

     * boolean for forcibly getting the logo from cache

     */

    TBool iForceGet;

    /**

     * boolean for to track whether the cache request has made or not

     */

    TBool iCacheReqMade;

    /**

     * response from the cache for the availability of logo(CacheNotValid,NotCached,CacheUseable)

     */

    TInt iResult;

    /**

     * status on cache checking

     */

    TBool iCheckingCache;

    /**

     * integer for the status of sending the logo

     */

    TInt iSendingLogo;

    /**

     * Using for temporarily till the isds provides urls

     */

    TInt iImageIndex;

    /**

     * this is used while making a conditional GET request

     */

    TTime iLastModifiedTime;

    /**

     * this is used while making a conditional GET request

     */

    TBuf8<KMAXHEADERLENGTHS> iETag;

    /**

     * this is used to track whether the request is conditional GET or non-conditional GET

     */

    TBool iIsConditionalGET;