<?php
/**
 * Event retention service.
 *
 * @package ZeroSpamForms
 */

namespace TwoOTwoCode\ZeroSpamForms\Logging;

defined( 'ABSPATH' ) || exit;

/**
 * Keeps event storage bounded and recent.
 */
final class EventRetentionService {
	/**
	 * Apply retention and max-record limits.
	 *
	 * @param array<int, SpamEvent> $events         Events.
	 * @param int                   $retention_days Retention days.
	 * @param int                   $max_records    Max records.
	 * @param int|null              $now            Current timestamp.
	 *
	 * @return array<int, SpamEvent>
	 */
	public function filter_events( array $events, int $retention_days, int $max_records, ?int $now = null ): array {
		$now            = null === $now ? time() : max( 1, $now );
		$retention_days = max( 1, min( 90, $retention_days ) );
		$max_records    = max( 25, min( 1000, $max_records ) );
		$cutoff         = $now - ( $retention_days * DAY_IN_SECONDS );
		$filtered       = array();

		foreach ( $events as $event ) {
			if ( ! $event instanceof SpamEvent ) {
				continue;
			}

			if ( $event->get_created_at() < $cutoff ) {
				continue;
			}

			$filtered[] = $event;
		}

		usort(
			$filtered,
			static function ( SpamEvent $first, SpamEvent $second ): int {
				return $second->get_created_at() <=> $first->get_created_at();
			}
		);

		return array_slice( $filtered, 0, $max_records );
	}
}