/******************************************************************************
 * Copyright (C) 2018 Kitsune Ral <kitsune-ral@users.sf.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#pragma once

#include "joinstate.h"

#include "events/stateevent.h"

namespace QMatrixClient
{
/// Room summary, as defined in MSC688
/**
 * Every member of this structure is an Omittable; as per the MSC, only
 * changed values are sent from the server so if nothing is in the payload
 * the respective member will be omitted. In particular, `heroes.omitted()`
 * means that nothing has come from the server; heroes.value().isEmpty()
 * means a peculiar case of a room with the only member - the current user.
 */
struct RoomSummary
{
    Omittable<int> joinedMemberCount;
    Omittable<int> invitedMemberCount;
    Omittable<QStringList> heroes; //< mxids of users to take part in the room
                                   //name

    bool isEmpty() const;
    /// Merge the contents of another RoomSummary object into this one
    /// \return true, if the current object has changed; false otherwise
    bool merge(const RoomSummary& other);

    friend QDebug operator<<(QDebug dbg, const RoomSummary& rs);
};

template <>
struct JsonObjectConverter<RoomSummary>
{
    static void dumpTo(QJsonObject& jo, const RoomSummary& rs);
    static void fillFrom(const QJsonObject& jo, RoomSummary& rs);
};

class SyncRoomData
{
public:
    QString roomId;
    JoinState joinState;
    RoomSummary summary;
    StateEvents state;
    RoomEvents timeline;
    Events ephemeral;
    Events accountData;

    bool timelineLimited;
    QString timelinePrevBatch;
    int unreadCount;
    int highlightCount;
    int notificationCount;

    SyncRoomData(const QString& roomId, JoinState joinState_,
                 const QJsonObject& room_);
    SyncRoomData(SyncRoomData&&) = default;
    SyncRoomData& operator=(SyncRoomData&&) = default;

    static const QString UnreadCountKey;
};

// QVector cannot work with non-copiable objects, std::vector can.
using SyncDataList = std::vector<SyncRoomData>;

class SyncData
{
public:
    SyncData() = default;
    explicit SyncData(const QString& cacheFileName);
    /** Parse sync response into room events
     * \param json response from /sync or a room state cache
     * \return the list of rooms with missing cache files; always
     *         empty when parsing response from /sync
     */
    void parseJson(const QJsonObject& json, const QString& baseDir = {});

    Events&& takePresenceData();
    Events&& takeAccountData();
    Events&& takeToDeviceEvents();
    SyncDataList&& takeRoomData();

    QString nextBatch() const { return nextBatch_; }

    QStringList unresolvedRooms() const { return unresolvedRoomIds; }

    static std::pair<int, int> cacheVersion() { return { 10, 0 }; }
    static QString fileNameForRoom(QString roomId);

private:
    QString nextBatch_;
    Events presenceData;
    Events accountData;
    Events toDeviceEvents;
    SyncDataList roomData;
    QStringList unresolvedRoomIds;

    static QJsonObject loadJson(const QString& fileName);
};
} // namespace QMatrixClient