/*
 * Copyright (C) 2019 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/Db.hpp"

#include <Wt/Dbo/FixedSqlConnectionPool.h>
#include <Wt/Dbo/backend/Sqlite3.h>

#include "database/Session.hpp"
#include "database/User.hpp"
#include "utils/Logger.hpp"

namespace Database {

// Session living class handling the database and the login
Db::Db(const std::filesystem::path& dbPath, std::size_t connectionCount)
{
	LMS_LOG(DB, INFO) << "Creating connection pool on file " << dbPath.string();

	std::unique_ptr<Wt::Dbo::backend::Sqlite3> connection {std::make_unique<Wt::Dbo::backend::Sqlite3>(dbPath.string())};
//	connection->setProperty("show-queries", "true");
	connection->executeSql("pragma journal_mode=WAL");
	connection->executeSql("pragma synchronous=normal");

	auto connectionPool = std::make_unique<Wt::Dbo::FixedSqlConnectionPool>(std::move(connection), connectionCount);
	connectionPool->setTimeout(std::chrono::seconds(10));

	_connectionPool = std::move(connectionPool);
}

Db::~Db()
{
	LMS_LOG(DB, DEBUG) << "Optimizing db...";
	executeSql("pragma optimize");
	LMS_LOG(DB, DEBUG) << "Optimizing db DONE";
}

void
Db::executeSql(const std::string& sql)
{
	ScopedConnection connection {*_connectionPool};
	connection->executeSql(sql);
}

Session&
Db::getTLSSession()
{
	static thread_local Session* tlsSession {};

	if (!tlsSession)
	{
		auto newSession {std::make_unique<Session>(*this)};
		tlsSession = newSession.get();

		{
			std::scoped_lock lock {_tlsSessionsMutex};
			_tlsSessions.push_back(std::move(newSession));
		}
	}

	return *tlsSession;
}

Db::ScopedConnection::ScopedConnection(Wt::Dbo::SqlConnectionPool& pool)
: _connectionPool {pool}
, _connection {_connectionPool.getConnection()}
{
}

Db::ScopedConnection::~ScopedConnection()
{
	_connectionPool.returnConnection(std::move(_connection));
}

Wt::Dbo::SqlConnection* Db::ScopedConnection::operator->() const
{
	return _connection.get();
}

} // namespace Database