<?php
declare(strict_types=1);
namespace App\Repository\Pdo;

use App\Repository\RiskControlRepository;
use PDO;

/**
 * 위험성평가 매핑: one row per (site, detection type).
 *
 * The UNIQUE key is (site, event_type) and MySQL treats NULL sites as distinct, so a plain
 * "INSERT ... ON DUPLICATE KEY UPDATE" would append a second global row instead of updating the
 * first. upsert() therefore looks the row up explicitly, with an IS NULL predicate for the
 * global case.
 */
final class PdoRiskControlRepository implements RiskControlRepository
{
    public function __construct(private PDO $pdo) {}

    public function listAll(?string $site): array
    {
        $sql = 'SELECT * FROM move_risk_controls';
        $args = [];
        if ($site !== null) { $sql .= ' WHERE site = ?'; $args[] = $site; }
        // Highest risk score first: the table is read to decide what to fix next.
        $sql .= ' ORDER BY (severity_rating * likelihood_rating) DESC, event_type ASC';
        $st = $this->pdo->prepare($sql);
        $st->execute($args);
        return array_map([self::class, 'mapRow'], $st->fetchAll());
    }

    public function upsert(array $row): void
    {
        $site = $row['site'] ?? null;
        $sql = 'SELECT control_id FROM move_risk_controls WHERE event_type = ? AND site '
             . ($site === null ? 'IS NULL' : '= ?');
        $st = $this->pdo->prepare($sql);
        $st->execute($site === null ? [$row['event_type']] : [$row['event_type'], $site]);
        $id = $st->fetchColumn();

        if ($id !== false) {
            $up = $this->pdo->prepare(
                'UPDATE move_risk_controls
                    SET hazard = ?, control = ?, severity_rating = ?, likelihood_rating = ?,
                        reviewed_by = ?, reviewed_at = ?, updated_at = ?
                  WHERE control_id = ?'
            );
            $up->execute([
                $row['hazard'], $row['control'], (int)$row['severity_rating'], (int)$row['likelihood_rating'],
                $row['reviewed_by'] ?? null, $row['reviewed_at'] ?? null, $row['updated_at'], (int)$id,
            ]);
            return;
        }
        $ins = $this->pdo->prepare(
            'INSERT INTO move_risk_controls (site, event_type, hazard, control, severity_rating,
                                             likelihood_rating, reviewed_by, reviewed_at, updated_at)
             VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)'
        );
        $ins->execute([
            $site, $row['event_type'], $row['hazard'], $row['control'],
            (int)$row['severity_rating'], (int)$row['likelihood_rating'],
            $row['reviewed_by'] ?? null, $row['reviewed_at'] ?? null, $row['updated_at'],
        ]);
    }

    public function delete(int $id, ?string $site): bool
    {
        $sql = 'DELETE FROM move_risk_controls WHERE control_id = ?';
        $args = [$id];
        if ($site !== null) { $sql .= ' AND site = ?'; $args[] = $site; }
        $st = $this->pdo->prepare($sql);
        $st->execute($args);
        return $st->rowCount() > 0;
    }

    private static function mapRow(array $r): array
    {
        return [
            'control_id' => (int)$r['control_id'],
            'site' => $r['site'] !== null ? (string)$r['site'] : null,
            'event_type' => (string)$r['event_type'],
            'hazard' => (string)$r['hazard'],
            'control' => (string)$r['control'],
            'severity_rating' => (int)$r['severity_rating'],
            'likelihood_rating' => (int)$r['likelihood_rating'],
            'risk_score' => (int)$r['severity_rating'] * (int)$r['likelihood_rating'],
            'reviewed_by' => $r['reviewed_by'] !== null ? (string)$r['reviewed_by'] : null,
            'reviewed_at' => $r['reviewed_at'] !== null ? (int)$r['reviewed_at'] : null,
            'updated_at' => (int)$r['updated_at'],
        ];
    }
}