/*
 * Copyright (C) 2015 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 "lmscore/database/Artist.hpp"

#include <Wt/Dbo/WtSqlTraits.h>

#include "lmscore/database/Cluster.hpp"
#include "lmscore/database/Release.hpp"
#include "lmscore/database/Session.hpp"
#include "lmscore/database/Track.hpp"
#include "lmscore/database/User.hpp"
#include "utils/Logger.hpp"
#include "SqlQuery.hpp"
#include "Utils.hpp"
#include "Traits.hpp"

namespace Database
{

Artist::Artist(const std::string& name, const std::optional<UUID>& MBID)
: _name {std::string(name, 0 , _maxNameLength)},
_sortName {_name},
_MBID {MBID ? MBID->getAsString() : ""}
{
}

std::vector<Artist::pointer>
Artist::getByName(Session& session, const std::string& name)
{
	session.checkSharedLocked();

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> res = session.getDboSession().find<Artist>()
		.where("name = ?").bind(std::string {name, 0, _maxNameLength})
		.orderBy("LENGTH(mbid) DESC"); // put mbid entries first

	return std::vector<Artist::pointer>(res.begin(), res.end());
}

Artist::pointer
Artist::getByMBID(Session& session, const UUID& mbid)
{
	session.checkSharedLocked();
	return session.getDboSession().find<Artist>().where("mbid = ?").bind(std::string {mbid.getAsString()}).resultValue();
}

Artist::pointer
Artist::getById(Session& session, ArtistId id)
{
	session.checkSharedLocked();
	return session.getDboSession().find<Artist>().where("id = ?").bind(id).resultValue();
}

bool
Artist::exists(Session& session, ArtistId id)
{
	session.checkSharedLocked();
	return session.getDboSession().query<int>("SELECT 1 FROM artist").where("id = ?").bind(id).resultValue() == 1;
}

Artist::pointer
Artist::create(Session& session, const std::string& name, const std::optional<UUID>& MBID)
{
	session.checkUniqueLocked();

	Artist::pointer res {session.getDboSession().add(std::make_unique<Artist>(name, MBID))};
	session.getDboSession().flush();

	return res;
}

template <typename T>
static
Wt::Dbo::Query<T>
createQuery(Session& session,
		const std::string& queryStr,
		const std::vector<ClusterId>& clusterIds,
		const std::vector<std::string_view>& keywords,
		std::optional<TrackArtistLinkType> linkType)
{
	session.checkSharedLocked();

	auto query {session.getDboSession().query<T>(queryStr)};
	query.join("track t ON t.id = t_a_l.track_id");
	query.join("track_artist_link t_a_l ON t_a_l.artist_id = a.id");

	if (linkType)
		query.where("t_a_l.type = ?").bind(*linkType);

	if (!keywords.empty())
	{
		std::vector<std::string> clauses;
		std::vector<std::string> sortClauses;

		for (std::string_view keyword : keywords)
		{
			clauses.push_back("a.name LIKE ? ESCAPE '" ESCAPE_CHAR_STR "'");
			query.bind("%" + escapeLikeKeyword(keyword) + "%");
		}

		for (std::string_view keyword : keywords)
		{
			sortClauses.push_back("a.sort_name LIKE ? ESCAPE '" ESCAPE_CHAR_STR "'");
			query.bind("%" + escapeLikeKeyword(keyword) + "%");
		}

		query.where("(" + StringUtils::joinStrings(clauses, " AND ") + ") OR (" + StringUtils::joinStrings(sortClauses, " AND ") + ")");
	}

	if (!clusterIds.empty())
	{
		std::ostringstream oss;
		oss << "a.id IN (SELECT DISTINCT a.id FROM artist a"
			" INNER JOIN track t ON t.id = t_a_l.track_id"
			" INNER JOIN track_artist_link t_a_l ON t_a_l.artist_id = a.id"
			" INNER JOIN cluster c ON c.id = t_c.cluster_id"
			" INNER JOIN track_cluster t_c ON t_c.track_id = t.id";

		WhereClause clusterClause;
		for (const ClusterId clusterId : clusterIds)
		{
			clusterClause.Or(WhereClause("c.id = ?"));
			query.bind(clusterId);
		}

		oss << " " << clusterClause.get();
		oss << " GROUP BY t.id,a.id HAVING COUNT(DISTINCT c.id) = " << clusterIds.size() << ")";

		query.where(oss.str());
	}

	return query;
}

std::vector<Artist::pointer>
Artist::getAll(Session& session)
{
	session.checkSharedLocked();

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> res = session.getDboSession().find<Artist>();
	return std::vector<pointer>(res.begin(), res.end());
}

std::vector<Artist::pointer>
Artist::getAll(Session& session, SortMethod sortMethod)
{
	session.checkSharedLocked();

	auto query {session.getDboSession().find<Artist>()};
	switch (sortMethod)
	{
		case Artist::SortMethod::None:
			break;
		case Artist::SortMethod::ByName:
			query.orderBy("name COLLATE NOCASE");
			break;
		case Artist::SortMethod::BySortName:
			query.orderBy("sort_name COLLATE NOCASE");
			break;
	}

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> res = query;
	return std::vector<pointer>(res.begin(), res.end());
}


std::vector<Artist::pointer>
Artist::getAll(Session& session, SortMethod sortMethod, std::optional<Range> range, bool& moreResults)
{
	session.checkSharedLocked();

	auto query {createQuery<Wt::Dbo::ptr<Artist>>(session, "SELECT a FROM Artist a", {}, {}, std::nullopt)};

	switch (sortMethod)
	{
		case Artist::SortMethod::None:
			break;
		case Artist::SortMethod::ByName:
			query.orderBy("a.name COLLATE NOCASE");
			break;
		case Artist::SortMethod::BySortName:
			query.orderBy("a.sort_name COLLATE NOCASE");
			break;
	}

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> collection = query
		.limit(range ? static_cast<int>(range->limit) + 1 : -1)
		.offset(range ? static_cast<int>(range->offset) : -1);

	std::vector<Artist::pointer> res (collection.begin(), collection.end());
	if (range && res.size() == static_cast<std::size_t>(range->limit) + 1)
	{
		moreResults = true;
		res.pop_back();
	}
	else
		moreResults = false;

	return res;
}

std::vector<ArtistId>
Artist::getAllIds(Session& session)
{
	session.checkSharedLocked();

	Wt::Dbo::collection<ArtistId> res = session.getDboSession().query<ArtistId>("SELECT id FROM artist");
	return std::vector<ArtistId>(res.begin(), res.end());
}

std::vector<ArtistId>
Artist::getAllIdsRandom(Session& session, const std::vector<ClusterId>& clusters, std::optional<TrackArtistLinkType> linkType, std::optional<std::size_t> size)
{
	session.checkSharedLocked();

	auto query {createQuery<ArtistId>(session, "SELECT DISTINCT a.id from artist a", clusters, {}, linkType)};

	Wt::Dbo::collection<ArtistId> res = query
		.orderBy("RANDOM()")
		.limit(size ? static_cast<int>(*size) : -1);

	return std::vector<ArtistId>(res.begin(), res.end());

}

std::vector<Artist::pointer>
Artist::getAllOrphans(Session& session)
{
	session.checkSharedLocked();
	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> res {session.getDboSession().query<Wt::Dbo::ptr<Artist>>("SELECT DISTINCT a FROM artist a WHERE NOT EXISTS(SELECT 1 FROM track t INNER JOIN track_artist_link t_a_l ON t_a_l.artist_id = a.id WHERE t.id = t_a_l.track_id)")};

	return std::vector<pointer>(res.begin(), res.end());
}

std::vector<ArtistId>
Artist::getAllIdsWithClusters(Session& session, std::optional<std::size_t> limit)
{
	session.checkSharedLocked();

	Wt::Dbo::collection<ArtistId> res = session.getDboSession().query<ArtistId>
		("SELECT DISTINCT a.id FROM artist a"
			" INNER JOIN track t ON t.id = t_a_l.track_id INNER JOIN track_artist_link t_a_l ON t_a_l.artist_id = a.id"
			" INNER JOIN track_cluster t_c ON t_c.track_id = t.id")
		.limit(limit ? static_cast<int>(*limit) : -1);

	return std::vector<ArtistId>(res.begin(), res.end());
}

std::vector<Artist::pointer>
Artist::getByClusters(Session& session, const std::vector<ClusterId>& clusters, SortMethod sortMethod)
{
	assert(!clusters.empty());

	session.checkSharedLocked();
	bool more{};
	return getByFilter(session, clusters, {}, std::nullopt, sortMethod, std::nullopt, more);
}

std::vector<Artist::pointer>
Artist::getByFilter(Session& session,
		const std::vector<ClusterId>& clusters,
		const std::vector<std::string_view>& keywords,
		std::optional<TrackArtistLinkType> linkType,
		SortMethod sortMethod,
		std::optional<Range> range,
		bool& moreResults)
{
	session.checkSharedLocked();

	auto query {createQuery<Wt::Dbo::ptr<Artist>>(session, "SELECT DISTINCT a from artist a", clusters, keywords, linkType)};
	switch (sortMethod)
	{
		case Artist::SortMethod::None:
			break;
		case Artist::SortMethod::ByName:
			query.orderBy("a.name COLLATE NOCASE");
			break;
		case Artist::SortMethod::BySortName:
			query.orderBy("a.sort_name COLLATE NOCASE");
			break;
	}

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> collection = query
		.limit(range ? static_cast<int>(range->limit) + 1 : -1)
		.offset(range ? static_cast<int>(range->offset) : -1);

	std::vector<pointer> res (collection.begin(), collection.end());

	if (range && res.size() == static_cast<std::size_t>(range->limit) + 1)
	{
		moreResults = true;
		res.pop_back();
	}
	else
		moreResults = false;

	return res;
}

std::vector<Artist::pointer>
Artist::getLastWritten(Session& session,
		std::optional<Wt::WDateTime> after,
		const std::vector<ClusterId>& clusters,
		std::optional<TrackArtistLinkType> linkType,
		std::optional<Range> range, bool& moreResults)
{
	session.checkSharedLocked();

	auto query {createQuery<Wt::Dbo::ptr<Artist>>(session, "SELECT DISTINCT a from artist a", clusters, {}, linkType)};

	if (after)
		query.where("t.file_last_write > ?").bind(*after);

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> collection = query
		.orderBy("t.file_last_write DESC")
		.limit(range ? static_cast<int>(range->limit) + 1 : -1)
		.offset(range ? static_cast<int>(range->offset) : -1);

	std::vector<pointer> res (collection.begin(), collection.end());

	if (range && res.size() == static_cast<std::size_t>(range->limit) + 1)
	{
		moreResults = true;
		res.pop_back();
	}
	else
		moreResults = false;

	return std::vector<pointer>(res.begin(), res.end());
}

std::vector<Artist::pointer>
Artist::getStarred(Session& session,
		User::pointer user,
		const std::vector<ClusterId>& clusters,
		std::optional<TrackArtistLinkType> linkType,
		SortMethod sortMethod,
		std::optional<Range> range, bool& moreResults)
{
	session.checkSharedLocked();

	auto query {createQuery<Wt::Dbo::ptr<Artist>>(session, "SELECT DISTINCT a from artist a", clusters, {}, linkType)};

	{
		std::ostringstream oss;
		oss << "a.id IN (SELECT DISTINCT a.id FROM artist a"
			" INNER JOIN user_artist_starred uas ON uas.artist_id = a.id"
			" INNER JOIN user u ON u.id = uas.user_id WHERE u.id = ?)";

		query.bind(user->getId());
		query.where(oss.str());
	}

	switch (sortMethod)
	{
		case Artist::SortMethod::None:
			break;
		case Artist::SortMethod::ByName:
			query.orderBy("name COLLATE NOCASE");
			break;
		case Artist::SortMethod::BySortName:
			query.orderBy("sort_name COLLATE NOCASE");
			break;
	}

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> collection = query
		.groupBy("a.id")
		.limit(range ? static_cast<int>(range->limit) + 1 : -1)
		.offset(range ? static_cast<int>(range->offset) : -1);

	std::vector<pointer> res (collection.begin(), collection.end());

	if (range && res.size() == static_cast<std::size_t>(range->limit) + 1)
	{
		moreResults = true;
		res.pop_back();
	}
	else
		moreResults = false;

	return std::vector<pointer>(res.begin(), res.end());
}

std::vector<Release::pointer>
Artist::getReleases(const std::vector<ClusterId>& clusterIds) const
{
	assert(session());

	WhereClause where;

	std::ostringstream oss;

	oss << "SELECT DISTINCT r FROM release r INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id INNER JOIN track t ON t.release_id = r.id";

	if (!clusterIds.empty())
	{
		oss << " INNER JOIN cluster c ON c.id = t_c.cluster_id INNER JOIN track_cluster t_c ON t_c.track_id = t.id";

		WhereClause clusterClause;

		for (auto id : clusterIds)
			clusterClause.Or(WhereClause("c.id = ?")).bind(id.toString());

		where.And(clusterClause);
	}

	where.And(WhereClause("a.id = ?")).bind(getId().toString());

	oss << " " << where.get();

	if (!clusterIds.empty())
		oss << " GROUP BY t.id HAVING COUNT(DISTINCT c.id) = " << clusterIds.size();

	oss << " ORDER BY t.date DESC, r.name COLLATE NOCASE";

	auto query {session()->query<Wt::Dbo::ptr<Release>>(oss.str())};

	for (const std::string& bindArg : where.getBindArgs())
		query.bind(bindArg);

	auto res {query.resultList()};
	return std::vector<Release::pointer>(res.begin(), res.end());
}

std::size_t
Artist::getReleaseCount() const
{
	assert(session());

	int res = session()->query<int>("SELECT COUNT(DISTINCT r.id) FROM release r INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id INNER JOIN track t ON t.release_id = r.id")
		.where("a.id = ?").bind(getId());
	return res;
}

std::vector<Track::pointer>
Artist::getTracks(std::optional<TrackArtistLinkType> linkType) const
{
	assert(session());

	auto query {session()->query<Wt::Dbo::ptr<Track>>("SELECT DISTINCT t FROM track t INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id")
		.where("a.id = ?").bind(getId())
		.orderBy("t.date DESC,t.release_id,t.disc_number,t.track_number")};

	if (linkType)
		query.where("t_a_l.type = ?").bind(*linkType);

	auto tracks {query.resultList()};
	return std::vector<Track::pointer>(tracks.begin(), tracks.end());
}

std::vector<Track::pointer>
Artist::getNonReleaseTracks(std::optional<TrackArtistLinkType> linkType, std::optional<Range> range, bool& moreResults) const
{
	assert(session());

	auto query {session()->query<Wt::Dbo::ptr<Track>>("SELECT t FROM track t INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id")
		.where("a.id = ?").bind(getId())
		.where("t.release_id is NULL")
		.orderBy("t.name")
		.limit(range ? static_cast<int>(range->limit) + 1 : -1)
		.offset(range ? static_cast<int>(range->offset) : -1)};

	if (linkType)
		query.where("t_a_l.type = ?").bind(*linkType);

	Wt::Dbo::collection<Wt::Dbo::ptr<Track>> tracks {query.resultList()};
	std::vector<Track::pointer> res(tracks.begin(), tracks.end());
	if (range && res.size() == static_cast<std::size_t>(range->limit) + 1)
	{
		moreResults = true;
		res.pop_back();
	}
	else
		moreResults = false;

	return res;
}

bool
Artist::hasNonReleaseTracks(std::optional<TrackArtistLinkType> linkType) const
{
	auto query {session()->query<Wt::Dbo::ptr<Track>>("SELECT t FROM track t INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id")
		.where("a.id = ?").bind(getId())
		.where("t.release_id is NULL")
		.orderBy("t.name")};

	if (linkType)
		query.where("t_a_l.type = ?").bind(*linkType);

	return !query.resultList().empty();
}

std::vector<Track::pointer>
Artist::getRandomTracks(std::optional<std::size_t> count) const
{
	assert(session());

	Wt::Dbo::collection<Wt::Dbo::ptr<Track>> tracks {session()->query<Wt::Dbo::ptr<Track>>("SELECT t from track t INNER JOIN artist a ON a.id = t_a_l.artist_id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id")
		.where("a.id = ?").bind(getId())
		.orderBy("RANDOM()")
		.limit(count ? static_cast<int>(*count) : -1)};

	return std::vector<Track::pointer>(tracks.begin(), tracks.end());
}

std::vector<Artist::pointer>
Artist::getSimilarArtists(EnumSet<TrackArtistLinkType> artistLinkTypes, std::optional<Range> range) const
{
	assert(session());

	std::ostringstream oss;
	oss <<
			"SELECT a FROM artist a"
			" INNER JOIN track_artist_link t_a_l ON t_a_l.artist_id = a.id"
			" INNER JOIN track t ON t.id = t_a_l.track_id"
			" INNER JOIN track_cluster t_c ON t_c.track_id = t.id"
				" WHERE "
					" t_c.cluster_id IN (SELECT c.id from cluster c"
											" INNER JOIN track t ON c.id = t_c.cluster_id"
											" INNER JOIN track_cluster t_c ON t_c.track_id = t.id"
											" INNER JOIN artist a ON a.id = t_a_l.artist_id"
											" INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id"
											" WHERE a.id = ?)"
					" AND a.id <> ?";

	if (!artistLinkTypes.empty())
	{
		oss << " AND t_a_l.type IN (";

		bool first {true};
		for (TrackArtistLinkType type : artistLinkTypes)
		{
			(void) type;
			if (!first)
				oss << ", ";
			oss << "?";
			first = false;
		}
		oss << ")";
	}

	Wt::Dbo::Query<Wt::Dbo::ptr<Artist>> query {session()->query<Wt::Dbo::ptr<Artist>>(oss.str())
		.bind(getId())
		.bind(getId())
		.groupBy("a.id")
		.orderBy("COUNT(*) DESC, RANDOM()")
		.limit(range ? static_cast<int>(range->limit) : -1)
		.offset(range ? static_cast<int>(range->offset) : -1)};

	for (TrackArtistLinkType type : artistLinkTypes)
		query.bind(type);

	Wt::Dbo::collection<Wt::Dbo::ptr<Artist>> res {query.resultList()};
	return std::vector<pointer>(res.begin(), res.end());
}

std::vector<std::vector<Cluster::pointer>>
Artist::getClusterGroups(std::vector<ClusterType::pointer> clusterTypes, std::size_t size) const
{
	assert(session());

	WhereClause where;

	std::ostringstream oss;
	oss << "SELECT c FROM cluster c INNER JOIN track t ON c.id = t_c.cluster_id INNER JOIN track_cluster t_c ON t_c.track_id = t.id INNER JOIN cluster_type c_type ON c.cluster_type_id = c_type.id INNER JOIN artist a ON t_a_l.artist_id = a.id INNER JOIN track_artist_link t_a_l ON t_a_l.track_id = t.id";

	where.And(WhereClause("a.id = ?")).bind(getId().toString());
	{
		WhereClause clusterClause;
		for (auto clusterType : clusterTypes)
			clusterClause.Or(WhereClause("c_type.id = ?")).bind(clusterType->getId().toString());

		where.And(clusterClause);
	}
	oss << " " << where.get();
	oss << "GROUP BY c.id ORDER BY COUNT(DISTINCT c.id) DESC";

	Wt::Dbo::Query<Wt::Dbo::ptr<Cluster>> query = session()->query<Wt::Dbo::ptr<Cluster>>( oss.str() );

	for (const std::string& bindArg : where.getBindArgs())
		query.bind(bindArg);

	Wt::Dbo::collection<Wt::Dbo::ptr<Cluster>> queryRes = query;

	std::map<ClusterTypeId, std::vector<Cluster::pointer>> clustersByType;
	for (const Cluster::pointer& cluster : queryRes)
	{
		if (clustersByType[cluster->getType()->getId()].size() < size)
			clustersByType[cluster->getType()->getId()].push_back(cluster);
	}

	std::vector<std::vector<Cluster::pointer>> res;
	for (const auto& [clusterTypeId, clusters] : clustersByType)
		res.push_back(clusters);

	return res;
}

void
Artist::setSortName(const std::string& sortName)
{
	_sortName = std::string(sortName, 0 , _maxNameLength);
}

} // namespace Database