/*
 * nheko Copyright (C) 2017  Konstantinos Sideris <siderisk@auth.gr>
 *
 * 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 3 of the License, 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

#include <QtNetwork/QNetworkAccessManager>

#include "MessageEvent.h"
#include "Profile.h"
#include "RoomMessages.h"
#include "Sync.h"

/*
 * MatrixClient provides the high level API to communicate with
 * a Matrix homeserver. All the responses are returned through signals.
 */
class MatrixClient : public QNetworkAccessManager
{
        Q_OBJECT
public:
        MatrixClient(QString server, QObject *parent = 0);

        // Client API.
        void initialSync() noexcept;
        void sync() noexcept;
        void sendRoomMessage(matrix::events::MessageEventType ty,
                             const QString &roomid,
                             const QString &msg,
                             const QString &url = "") noexcept;
        void login(const QString &username, const QString &password) noexcept;
        void registerUser(const QString &username,
                          const QString &password,
                          const QString &server) noexcept;
        void versions() noexcept;
        void fetchRoomAvatar(const QString &roomid, const QUrl &avatar_url);
        void fetchUserAvatar(const QString &userId, const QUrl &avatarUrl);
        void fetchOwnAvatar(const QUrl &avatar_url);
        void downloadImage(const QString &event_id, const QUrl &url);
        void messages(const QString &room_id, const QString &from_token, int limit = 30) noexcept;
        void uploadImage(const QString &roomid, const QString &filename);
        void joinRoom(const QString &roomIdOrAlias);
        void leaveRoom(const QString &roomId);

        inline QUrl getHomeServer();
        inline int transactionId();
        inline void incrementTransactionId();

        void reset() noexcept;

public slots:
        void getOwnProfile() noexcept;
        void logout() noexcept;

        inline void setServer(const QString &server);
        inline void setAccessToken(const QString &token);
        inline void setNextBatchToken(const QString &next_batch);

signals:
        void loginError(const QString &error);
        void registerError(const QString &error);
        void versionError(const QString &error);

        void loggedOut();

        void loginSuccess(const QString &userid, const QString &homeserver, const QString &token);
        void registerSuccess(const QString &userid,
                             const QString &homeserver,
                             const QString &token);
        void versionSuccess();
        void imageUploaded(const QString &roomid, const QString &filename, const QString &url);

        void roomAvatarRetrieved(const QString &roomid, const QPixmap &img);
        void userAvatarRetrieved(const QString &userId, const QImage &img);
        void ownAvatarRetrieved(const QPixmap &img);
        void imageDownloaded(const QString &event_id, const QPixmap &img);

        // Returned profile data for the user's account.
        void getOwnProfileResponse(const QUrl &avatar_url, const QString &display_name);
        void initialSyncCompleted(const SyncResponse &response);
        void syncCompleted(const SyncResponse &response);
        void syncFailed(const QString &msg);
        void messageSent(const QString &event_id, const QString &roomid, const int txn_id);
        void emoteSent(const QString &event_id, const QString &roomid, const int txn_id);
        void messagesRetrieved(const QString &room_id, const RoomMessages &msgs);
        void joinedRoom(const QString &room_id);
        void leftRoom(const QString &room_id);

private slots:
        void onResponse(QNetworkReply *reply);

private:
        enum class Endpoint {
                GetOwnAvatar,
                GetOwnProfile,
                GetProfile,
                Image,
                InitialSync,
                ImageUpload,
                Login,
                Logout,
                Messages,
                Register,
                RoomAvatar,
                SendRoomMessage,
                Sync,
                UserAvatar,
                Versions,
                JoinRoom,
                LeaveRoom,
        };

        // Response handlers.
        void onGetOwnAvatarResponse(QNetworkReply *reply);
        void onGetOwnProfileResponse(QNetworkReply *reply);
        void onImageResponse(QNetworkReply *reply);
        void onInitialSyncResponse(QNetworkReply *reply);
        void onImageUploadResponse(QNetworkReply *reply);
        void onLoginResponse(QNetworkReply *reply);
        void onLogoutResponse(QNetworkReply *reply);
        void onMessagesResponse(QNetworkReply *reply);
        void onRegisterResponse(QNetworkReply *reply);
        void onRoomAvatarResponse(QNetworkReply *reply);
        void onSendRoomMessage(QNetworkReply *reply);
        void onSyncResponse(QNetworkReply *reply);
        void onUserAvatarResponse(QNetworkReply *reply);
        void onVersionsResponse(QNetworkReply *reply);
        void onJoinRoomResponse(QNetworkReply *reply);
        void onLeaveRoomResponse(QNetworkReply *reply);

        // Client API prefix.
        QString clientApiUrl_;

        // Media API prefix.
        QString mediaApiUrl_;

        // The Matrix server used for communication.
        QUrl server_;

        // The access token used for authentication.
        QString token_;

        // Increasing transaction ID.
        int txn_id_;

        // Token to be used for the next sync.
        QString next_batch_;
};

inline QUrl
MatrixClient::getHomeServer()
{
        return server_;
}

inline int
MatrixClient::transactionId()
{
        return txn_id_;
}

inline void
MatrixClient::setServer(const QString &server)
{
        server_ = QUrl(QString("https://%1").arg(server));
}

inline void
MatrixClient::setAccessToken(const QString &token)
{
        token_ = token;
}

inline void
MatrixClient::setNextBatchToken(const QString &next_batch)
{
        next_batch_ = next_batch;
}

inline void
MatrixClient::incrementTransactionId()
{
        txn_id_ += 1;
}