/*
 *   Copyright (C) 2016 Christian Mollekopf <chrigi_1@fastmail.fm>
 *
 *   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 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, write to the
 *   Free Software Foundation, Inc.,
 *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
 */
#pragma once

#include "query.h"
#include "storage.h"
#include "resultset.h"
#include "typeindex.h"
#include "query.h"
#include "entitybuffer.h"

class DataStoreQuery {
public:
    typedef QSharedPointer<DataStoreQuery> Ptr;

    DataStoreQuery(const Sink::Query &query, const QByteArray &type, Sink::Storage::Transaction &transaction, TypeIndex &typeIndex, std::function<QVariant(const Sink::Entity &entity, const QByteArray &property)> getProperty);
    ResultSet execute();
    ResultSet update(qint64 baseRevision);

protected:

    typedef std::function<bool(const QByteArray &uid, const Sink::EntityBuffer &entityBuffer)> FilterFunction;
    typedef std::function<void(const QByteArray &uid, const Sink::EntityBuffer &entityBuffer)> BufferCallback;

    virtual QVariant getProperty(const Sink::Entity &entity, const QByteArray &property);

    virtual void readEntity(const QByteArray &key, const BufferCallback &resultCallback);

    virtual ResultSet loadInitialResultSet(QSet<QByteArray> &remainingFilters, QByteArray &remainingSorting);
    virtual ResultSet loadIncrementalResultSet(qint64 baseRevision, QSet<QByteArray> &remainingFilters);

    virtual ResultSet filterAndSortSet(ResultSet &resultSet, const FilterFunction &filter, const QByteArray &sortProperty);
    virtual ResultSet postSortFilter(ResultSet &resultSet);
    virtual FilterFunction getFilter(const QSet<QByteArray> &remainingFilters);

    ResultSet createFilteredSet(ResultSet &resultSet, const std::function<bool(const QByteArray &, const Sink::EntityBuffer &buffer)> &);

    Sink::Query mQuery;
    Sink::Storage::Transaction &mTransaction;
    const QByteArray mType;
    TypeIndex &mTypeIndex;
    Sink::Storage::NamedDatabase mDb;
    std::function<QVariant(const Sink::Entity &entity, const QByteArray &property)> mGetProperty;
    bool mInitialQuery;
};