/**

* Copyright (c) 2010 Sasken Communication Technologies Ltd.

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the "{License}"

* which accompanies  this distribution, and is available

* at the URL "{LicenseUrl}".

*

* Initial Contributors:

* Narasimhulu Kavadapu, Sasken Communication Technologies Ltd - Initial contribution

*

* Contributors:

*

* Description:

* class to maintian session & all credential keys.

*/

#ifndef FBSESSION_H

#define FBSESSION_H

#include <QObject>

#include <QList>

#include <QString>

#include <QSettings>

#include <QDateTime>

#include "smfcredmgrclient.h"

#include "authAppConstants.h"

// FORWARD DECLARATIONS

class FBRequest;

const QString KFacebokkKeysFileName = "c://Data//FacebookKeys.txt";

///////////////////////////////////////////////////////////////////////////////////////////////////

/**

 * An FBSession represents a single user's authenticated session for a Facebook application.

 *

 * To create a session, you must use the session key of your application (which can

 * be found on the Facebook developer website).  You may then use the login dialog to ask

 * the user to enter their email address and password.  If successful, you will get back a

 * session key which can be used to make requests to the Facebook API.

 *

 * Session keys are cached and stored on the disk of the device so that you do not need to ask

 * the user to login every time they launch the app.  To restore the last active session, call the

 * resume method after instantiating your session.

 */

class FBSession : public QObject

{

    Q_OBJECT

private:

    /**

      * the queue of requests

      */

    QList<FBRequest*>           iRequestQueue;

    /**

     * Your application's API key, as passed to the constructor.

     */

    QString iApiKey;

    /**

     * Your application's API secret, as passed to the constructor.

     */

    QString iApiSecret;

    /**

     * The URL to call to create a session key after login.

     *

     * This is an alternative to calling auth.getSession directly using the secret key.

     */

    QString iGetSessionProxy;

    /**

     * The current user's session key.

     */

    QString iSessionKey;

    /**

     * The current user's session secret.

     */

    QString iSessionSecret;

    /**

     * The expiration date of the session key.

     */

    QDateTime iExpirationDate;

    /**

      * the time at which the last request was performed, this is used to prevent

      * too many requests going to the server at once.

      */

    QDateTime   iLastRequestTime;

    int         iRequestBurstCount;

    /**

      * The settings object used to restore session from the disk.

      */

    QSettings   iSettings;

    /**

      * The Credentail Object used to store auth data

      */

    SmfCredMgrClient* m_Client; 

    /**

      * Variable to store 

      */ 

    QString iCMRegToken;

signals: /* the signals ommitted by FBSession */

    /**

      * Called when session logged in sucessfully

      * @param SessionKey is the fb assigned session key

      */

    void sessionDidLogin (QString SessionKey);

    /**

     * Called when a user closes the login dialog without logging in.

     */

    void sessionDidNotLogin ();

    /**

     * Called when a session is about to log out.

     * @param aUid is the fb assigned session id

     */

    void sessionWillLogout ();

    /**

     * Called when a session has logged out.

     */

    void sessionDidLogout ();

private slots:

    /**

      * handler function for the timer fired from startFlushTimer() function

      */

    void requestTimerReady();

public: /* class functions */

    /**

     * The globally shared session instance.

     */

    static FBSession* session();

    /**

     * Sets the globally shared session instance.

     *

     * This session is not retained, so you are still responsible for retaining it yourself.  The

     * first session that is created is automatically stored here.

     */

    static void setSession(FBSession* aSession);

    /**

     * Constructs a session and stores it as the globally shared session instance.

     *

     * @param aSessionProxy a url to that proxies auth.getSession

     */

    static FBSession* sessionForApplication ( const QString& aKey, const QString& aSecret, const QString& aSessionProxy);

public: /* instance functions */

    /**

     * Constructs a session for an application.

     *

     * @param secret the application secret (optional)

     * @param getSessionProxy a url to that proxies auth.getSession (optional)

     */

    FBSession( const QString& aKey, const QString& aSecret, const QString& aSessionProxy );

    /**

      * Destructor

      */

    ~FBSession();

    /**

     * Begins a session for a user with a given key and secret.

     */

    void beginSession ( const QString& aSessionKey, const QString& aSessionSecret, const QDateTime& aExpires );

    /**

     * Resumes a previous session whose uid, session key, and secret are cached on disk.

     */

     bool resume();

    /**

     * Cancels a login (no-op if the login is already complete).

     */

    void cancelLogin();

    /**

     * Ends the current session and deletes the uid, session key, and secret from disk.

     */

    void logout();

    /**

     * Sends a fully configured request to the server for execution.

     */

    void send (FBRequest* aRequest);

    /**

      * @return const QString& http:// URL to the facebook REST server

      */

    const QString& apiURL() const;

    /**

      * @return const QString& https:// URL to the secure facebook REST server

      */

    const QString& apiSecureURL() const;

    /**

     * Determines if the session is active and connected.

     * @return bool true if connected

     */

    bool isConnected() const;

    /**

      * @return const QString& the api secret

      */

    const QString& apiSecret() const { return iApiSecret; }

    /**

      * @return const QString& the GET? session proxy

      */

    const QString& getSessionProxy() const { return iGetSessionProxy; }

    /**

      * @return api key for this session

      */

    const QString& apiKey() const { return iApiKey; }

    /**

      * @return the session secret

      */

    const QString& sessionSecret() const { return iSessionSecret; }

    /**

      * @return the session key

      */

    const QString& sessionKey() const { return iSessionKey; }

private:

    /**

      * Saves the fb connect session information to disk

      */

    void save();

    /**

      * Forgets any fb connect session information saved to disk

      */

    void unsave();

    void startFlushTimer();

    /**

      * @param aRequest, the request to add to the session queue, owner ship is transferred to the session

      */

    void enqueueRequest(FBRequest* aRequest);

    /**

      * @param aRequest, the request to perform.

      * @param aEnqueue, if true add to queue if cant perform the request right now

      */

    bool performRequest(FBRequest* aRequest, bool aEnqueue);

    /**

      * flush the queue but performingRequest on the requests in the queue, if cant perform the request, waits a while using

      * startFlushTimer() and then tries to continue ..

      */

    void flushRequestQueue();

};

#endif // FBSESSION_H