/*
 * Copyright (C) 2018 Emeric Poupon
 *
 * This file is part of LMS.
 *
 * LMS 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.
 *
 * LMS 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 LMS.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "database/TrackFeatures.hpp"

#include <boost/property_tree/json_parser.hpp>
#include <boost/property_tree/ptree.hpp>

#include "core/ILogger.hpp"
#include "database/Directory.hpp"
#include "database/Session.hpp"
#include "database/Track.hpp"

#include "IdTypeTraits.hpp"
#include "Utils.hpp"

namespace lms::db
{

    TrackFeatures::TrackFeatures(ObjectPtr<Track> track, const std::string& jsonEncodedFeatures)
        : _data{ jsonEncodedFeatures }
        , _track{ getDboPtr(track) }
    {
    }

    TrackFeatures::pointer TrackFeatures::create(Session& session, ObjectPtr<Track> track, const std::string& jsonEncodedFeatures)
    {
        return session.getDboSession()->add(std::unique_ptr<TrackFeatures>{ new TrackFeatures{ track, jsonEncodedFeatures } });
    }

    std::size_t TrackFeatures::getCount(Session& session)
    {
        session.checkReadTransaction();

        return utils::fetchQuerySingleResult(session.getDboSession()->query<int>("SELECT COUNT(*) FROM track_features"));
    }

    TrackFeatures::pointer TrackFeatures::find(Session& session, TrackFeaturesId id)
    {
        session.checkReadTransaction();

        return utils::fetchQuerySingleResult(session.getDboSession()->find<TrackFeatures>().where("id = ?").bind(id));
    }

    TrackFeatures::pointer TrackFeatures::find(Session& session, TrackId trackId)
    {
        session.checkReadTransaction();

        return utils::fetchQuerySingleResult(session.getDboSession()->find<TrackFeatures>().where("track_id = ?").bind(trackId));
    }

    RangeResults<TrackFeaturesId> TrackFeatures::find(Session& session, std::optional<Range> range)
    {
        session.checkReadTransaction();

        auto query{ session.getDboSession()->query<TrackFeaturesId>("SELECT id from track_features") };

        return utils::execRangeQuery<TrackFeaturesId>(query, range);
    }

    FeatureValues TrackFeatures::getFeatureValues(const FeatureName& featureNode) const
    {
        FeatureValuesMap featuresValuesMap{ getFeatureValuesMap({ featureNode }) };
        return std::move(featuresValuesMap[featureNode]);
    }

    FeatureValuesMap TrackFeatures::getFeatureValuesMap(const std::unordered_set<FeatureName>& featureNames) const
    {
        FeatureValuesMap res;

        try
        {
            std::istringstream iss{ _data };
            boost::property_tree::ptree root;

            boost::property_tree::read_json(iss, root);

            for (const FeatureName& featureName : featureNames)
            {
                FeatureValues& featureValues{ res[featureName] };

                auto node{ root.get_child(featureName) };

                bool hasChildren = false;
                for (const auto& child : node.get_child(""))
                {
                    hasChildren = true;
                    featureValues.push_back(child.second.get_value<double>());
                }

                if (!hasChildren)
                    featureValues.push_back(node.get_value<double>());
            }
        }
        catch (boost::property_tree::ptree_error& error)
        {
            LMS_LOG(DB, ERROR, "Track " << _track.id() << ": ptree exception: " << error.what());
            res.clear();
        }

        return res;
    }

} // namespace lms::db