/*

* Copyright (c) 2008-2009 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:  MessageDispatcher

*

*/

#ifndef MESSAGEDISPATCHER_H

#define MESSAGEDISPATCHER_H

#include <string>

#include <memory>

#include "javaosheaders.h"

#include "javastorageentry.h"

#include "javastorage.h"

#include "javastoragemessage.h"

namespace java

{

namespace comms

{

class CommsMessage;

}  // end namespace comms

namespace storage

{

class JavaDataAccess;

class StatementUtils;

/**

 * MessageDispatcher takes care of message handling. It creates messages for

 * the storage and gives them for sending and construct response object from

 * the message response if needed.

 */

OS_NONSHARABLE_CLASS(MessageDispatcher)

{

    friend class JavaStorageImpl;

public:

    /**

     * Destructor.

     */

    ~MessageDispatcher();

    /**

     * CreateAndSendMessage for short storage statements. These are

     * transaction and connection handling requests.

     *

     * @param aMsgId message identifier.

     * @param aHeaders connection headers.

     * @param aStorageName storage name to be opened. This is used only when

     *                     connection is opened.

     * @return sessionID string if connection is opened, not used otherwise.

     * @throws JavaStorageException if unknown message id or error response

     *         received from the storage.

     */

    std::string createAndSendMessage(

        JavaStorageMessage::MessageIdentifier aMsgId,

        const std::string& aHeaders,

        const std::string& aStorageName

    );

    /**

     * CreateAndSendMessage for storage statements.

     *

     * @param aMsgId message identifier.

     * @param aHeaders connection headers.

     * @param aTableName table where statement is executed.

     * @param aEntry Application entry holding statement data. It contains e.g.

     *               entries written to storage table.

     * @return amount of removed storage entries. This is used only when data

     *         is removed from the storage.

     * @throws JavaStorageException if unknown message id or error response

     *         received from the storage.

     */

    int createAndSendMessage(

        JavaStorageMessage::MessageIdentifier aMsgId,

        const std::string& aHeaders,

        const std::string& aTableName,

        const java::storage::JavaStorageApplicationEntry_t& aEntry

    );

    /**

     * Handlesearch handles search statements. It creates SQL statement

     * out of entry, handles communication and constructs application list

     * from response.

     *

     * @param aMsgId message identifier.

     * @param aHeaders connection headers.

     * @param aTableName table where statement is executed.

     * @param aEntry Application entry holding statement data. It contains

     *               search query data.

     * @param[out] aAppList response object. Each application represents one row.

     * @throws JavaStorageException if unknown message id, error response

     *         received from the storage or invalid data structure detected.

     */

    void handleSearch(

        JavaStorageMessage::MessageIdentifier aMsgId,

        const std::string& aHeaders,

        const std::string& aTableName,

        const java::storage::JavaStorageApplicationEntry_t& aEntry,

        JavaStorageApplicationList_t& aAppList

    );

    /**

     * HandleUpdate hadles update statements. It creates SQL statement

     * out of entries and send it to storage for execution.

     *

     * @param aMsgId message identifier.

     * @param aHeaders connection headers.

     * @param aTableName table where statement is executed.

     * @param aUpdateEntry Application entry holding updated data.

     * @param aMatchEntry Application entry holding data to match content

     *                    to be updated.

     * @throws JavaStorageException if unknown message id or error response

     *         received from the storage.

     */

    void handleUpdate(

        JavaStorageMessage::MessageIdentifier aMsgId,

        const std::string& aHeaders,

        const std::string& aTableName,

        const JavaStorageApplicationEntry_t& aUpdateEntry,

        const JavaStorageApplicationEntry_t& aMatchEntry);

private:

    /**

     * Private constructor. Creates data access object that is used to

     * communicate with the storage.

     */

    MessageDispatcher();

    /**

     * Populate single entry. If response contains more than one application

     * entries they are ignored. If response contains malformed entries

     * population is stopped and already populated valid entries are left

     * populated for a robustness sake.

     *

     * @param aReceivedMessage response message from the storage as wstring

     *                         representation.

     * @param[out] aEntry Application entry populated with response message

     *                    content. Entry is left empty if no entries found.

     */

    void populateEntry(comms::CommsMessage& aReceivedMessage,

                       JavaStorageApplicationEntry_t& aEntry);

    /**

     * Populate application list. If response contains malformed application

     * entries population is stopped and already populated valid entries are

     * left populated for a robustness sake.

     *

     * @param aReceivedMessage response message from the storage as wstring

     *                         representation.

     * @param[out] aAppList Application list populated with response message

     *                    content. List is left empty if no entries found.

     */

    void populateEntry(comms::CommsMessage& aReceivedMessage,

                       JavaStorageApplicationList_t& aAppList);

    /**

     * Create message header.

     *

     * @param aMsgId message identifier.

     * @param aHeaders current headers.

     */

    void createHeader(int aMgsId, std::string& aHeaders);

    /**

     * Read error message from received message.

     *

     * @param aReceivedMessage received message.

     * @param[out] aErrMsg error message.

     */

    void readErrorMessage(comms::CommsMessage& aReceivedMessage,

                          std::string& aErrMsg);

private:

    std::auto_ptr<JavaDataAccess> mDataAccess;

    std::auto_ptr<StatementUtils> mUtils;

};

} // end namespace storage

} // end namespace java

#endif // MESSAGEDISPATCHER_H