<?php
/*
 * 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.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

namespace MediaWiki\CheckUser\SuggestedInvestigations\Services;

use InvalidArgumentException;
use MediaWiki\CheckUser\CheckUserQueryInterface;
use MediaWiki\CheckUser\SuggestedInvestigations\Model\CaseStatus;
use MediaWiki\CheckUser\SuggestedInvestigations\Model\SuggestedInvestigationsCase;
use MediaWiki\CheckUser\SuggestedInvestigations\Signals\SuggestedInvestigationsSignalMatchResult;
use MediaWiki\Config\ServiceOptions;
use Psr\Log\LoggerInterface;
use RuntimeException;
use Wikimedia\Rdbms\IConnectionProvider;

class SuggestedInvestigationsCaseLookupService {

	public const CONSTRUCTOR_OPTIONS = [
		'CheckUserSuggestedInvestigationsEnabled',
	];

	public function __construct(
		private readonly ServiceOptions $options,
		private readonly IConnectionProvider $dbProvider,
		private readonly LoggerInterface $logger,
	) {
		$this->options->assertRequiredOptions( self::CONSTRUCTOR_OPTIONS );
	}

	/**
	 * Looks up cases that match a given signal. Ignores the allowMerging flag on the signal.
	 * @throws InvalidArgumentException if a negative signal match is provided
	 * @param SuggestedInvestigationsSignalMatchResult $signal
	 * @param CaseStatus[]|null $statuses If set, only cases with these statuses will be returned.
	 * If null, all cases will be returned.
	 * @return SuggestedInvestigationsCase[]
	 */
	public function getCasesForSignal(
		SuggestedInvestigationsSignalMatchResult $signal,
		?array $statuses = null
	): array {
		if ( !$this->options->get( 'CheckUserSuggestedInvestigationsEnabled' ) ) {
			throw new RuntimeException( 'Suggested Investigations is not enabled' );
		}

		if ( !$signal->isMatch() ) {
			throw new InvalidArgumentException( 'Cannot look up for a negative signal match' );
		}

		if ( $statuses === [] ) {
			return [];
		}

		$dbr = $this->dbProvider->getReplicaDatabase( CheckUserQueryInterface::VIRTUAL_DB_DOMAIN );

		$queryBuilder = $dbr->newSelectQueryBuilder()
			->select( [ 'sic_id', 'sic_status', 'sic_status_reason' ] )
			->from( 'cusi_signal' )
			->join( 'cusi_case', null, 'sis_sic_id = sic_id' )
			->where( [
				'sis_name' => $signal->getName(),
				'sis_value' => $signal->getValue(),
			] )
			->caller( __METHOD__ );

		// @phan-suppress-next-line PhanImpossibleTypeComparison Phan thinks null is matched by `=== []` but it's not
		if ( $statuses !== null ) {
			$queryBuilder->where( [
				'sic_status' => array_map( static fn ( $s ) => $s->value, $statuses ),
			] );
		}

		$rows = $queryBuilder->fetchResultSet();
		$cases = [];
		foreach ( $rows as $row ) {
			$caseStatus = CaseStatus::tryFrom( (int)$row->sic_status );
			if ( $caseStatus === null ) {
				$this->logger->error(
					'Invalid status "{status}" of a Suggested Investigations case with id "{caseId}"',
					[ 'status' => $row->sic_status, 'caseId' => $row->sic_id ]
				);
				continue;
			}

			$cases[] = new SuggestedInvestigationsCase( (int)$row->sic_id, $caseStatus, $row->sic_status_reason );
		}

		return $cases;
	}
}