<?php
declare(strict_types=1);


namespace OneClickFormSync\Queue;

if (!defined('ABSPATH')) {
    exit;
}

use OneClickFormSync\Contracts\QueueRepositoryInterface;

/**
 * Handles processing of pending queue items in a cron task.
 */
class CronProcessor
{
    /**
     * @var QueueService
     */
    private QueueService $queueService;

    /**
     * @var QueueRepositoryInterface
     */
    private QueueRepositoryInterface $queueRepository;

    /**
     * CronProcessor constructor.
     *
     * @param QueueService $queueService
     * @param QueueRepositoryInterface $queueRepository
     */
    public function __construct(QueueService $queueService, QueueRepositoryInterface $queueRepository)
    {
        $this->queueService    = $queueService;
        $this->queueRepository = $queueRepository;
    }

    /**
     * Load pending items and process them.
     *
     * @return int Number of processed items.
     */
    public function processQueue(): int
    {
        // Concurrency lock using transients to prevent overlapping cron runs.
        $lockKey = 'oneclickformsync_cron_processing_lock';
        if (get_transient($lockKey) !== false) {
            return 0;
        }

        // Lock for 5 minutes.
        set_transient($lockKey, '1', 300);

        $processedCount = 0;
        try {
            // Process up to 10 pending items per cron run.
            $pendingItems = $this->queueRepository->findPending(10);

            foreach ($pendingItems as $item) {
                $this->queueService->processItem($item);
                $processedCount++;
            }
        } finally {
            delete_transient($lockKey);
        }

        return $processedCount;
    }
}