/* ============================================================
 *
 * This file is a part of digiKam project
 * http://www.digikam.org
 *
 * Date        : 2008-12-26
 * Description : a kipi plugin to export images to Facebook web service
 *
 * Copyright (C) 2008-2009 by Luka Renko <lure at kubuntu dot org>
 *
 * This program is free software; you can redistribute it
 * and/or modify it under the terms of the GNU General
 * Public License as published by the Free Software Foundation;
 * either version 2, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * ============================================================ */

#ifndef FBTALKER_H
#define FBTALKER_H

// Qt includes

#include <QList>
#include <QString>
#include <QTime>
#include <QObject>
#include <QUrl>
#include <QNetworkReply>
#include <QNetworkAccessManager>

// local includes

#include "fbitem.h"

class QDomElement;
class QDialog;

namespace KIPIFacebookPlugin
{

class FbTalker : public QObject
{
    Q_OBJECT

public:

    FbTalker(QWidget* const parent);
    ~FbTalker();

    QString      getAccessToken()    const;
    unsigned int getSessionExpires() const;

    FbUser  getUser() const;

    bool    loggedIn() const;
    void    cancel();
    void    authenticate(const QString& accessToken,  unsigned int sessionExpires);
    void    exchangeSession(const QString& sessionKey);
    void    logout();

    void    listAlbums(long long userID = 0);

    void    createAlbum(const FbAlbum& album);

    bool    addPhoto(const QString& imgPath, const QString& albumID,
                     const QString& caption);

Q_SIGNALS:

    void signalBusy(bool val);
    void signalLoginProgress(int step, int maxStep = 0, const QString& label = QString());
    void signalLoginDone(int errCode, const QString& errMsg);
    void signalAddPhotoDone(int errCode, const QString& errMsg);
    void signalCreateAlbumDone(int errCode, const QString& errMsg, const QString &newAlbumID);
    void signalListAlbumsDone(int errCode, const QString& errMsg, const QList <FbAlbum>& albumsList);

private:

    enum State
    {
        FB_GETLOGGEDINUSER = 0,
        FB_LISTALBUMS,
        FB_CREATEALBUM,
        FB_ADDPHOTO,
        FB_EXCHANGESESSION
    };

private:

    //QString getApiSig(const QMap<QString, QString>& args);
    QString getCallString(const QMap<QString, QString>& args);
    void    authenticationDone(int errCode, const QString& errMsg);
    void    doOAuth();
    void    getLoggedInUser();

    QString errorToText(int errCode, const QString& errMsg);
    int parseErrorResponse(const QDomElement& e, QString& errMsg);
    void parseExchangeSession(const QByteArray& data);
    void parseResponseGetLoggedInUser(const QByteArray& data);
    void parseResponseAddPhoto(const QByteArray& data);
    void parseResponseCreateAlbum(const QByteArray& data);
    void parseResponseListAlbums(const QByteArray& data);

private Q_SLOTS:

    void slotFinished(QNetworkReply* reply);
    void slotAccept();
    void slotReject();

private:

    QDialog*               m_dialog;
    QWidget*               m_parent;

    QByteArray             m_buffer;

    QUrl                   m_apiURL;
    QString                m_apiVersion;
    QString                m_secretKey;
    QString                m_appID;

    bool                   m_loginInProgress;
    QString                m_accessToken;

    /* Session expiration
     * 0 = doesn't expire or has been invalidated; rest = time of expiry
     */
    unsigned int           m_sessionExpires;
    QTime                  m_callID;

    FbUser                 m_user;

    QNetworkAccessManager* m_netMngr;

    QNetworkReply*         m_reply;

    State                  m_state;
};

} // namespace KIPIFacebookPlugin

#endif /* FBTALKER_H */
