<?php

declare(strict_types=1);

namespace CrocoAI\DataBridge\Infrastructure;

// Lock release is an atomic conditional delete against current option-table state.
// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery

final class WorkerLock
{
    private const OPTION = 'crocoai_dbridge_worker_lock';

    private ?string $token = null;

    public function acquire(string $owner, int $ttl = 120): bool
    {
        $ttl = max(30, $ttl);
        $token = wp_generate_uuid4();
        $value = [
            'token' => $token,
            'owner' => sanitize_key($owner),
            'expires' => time() + $ttl,
        ];

        if (!add_option(self::OPTION, $value, '', false)) {
            $current = get_option(self::OPTION, []);
            if (!is_array($current) || (int) ($current['expires'] ?? 0) >= time()) {
                return false;
            }
            delete_option(self::OPTION);
            /** @phpstan-ignore-next-line A concurrent request may acquire the option after deletion. */
            if (!add_option(self::OPTION, $value, '', false)) {
                return false;
            }
        }

        $this->token = $token;
        return true;
    }

    public function release(): void
    {
        if ($this->token === null) {
            return;
        }
        $current = get_option(self::OPTION, []);
        if (is_array($current) && hash_equals($this->token, (string) ($current['token'] ?? ''))) {
            delete_option(self::OPTION);
        }
        $this->token = null;
    }

    public static function releaseJob(int $jobId): void
    {
        $current = get_option(self::OPTION, []);
        $owner = is_array($current) ? (string) ($current['owner'] ?? '') : '';
        if (!in_array($owner, ['publication-' . $jobId, 'media-' . $jobId], true)) {
            return;
        }

        // Compare the complete serialized value so a replacement lock acquired
        // after this read cannot be deleted by the cancellation request.
        global $wpdb;
        $deleted = $wpdb->query($wpdb->prepare(
            "DELETE FROM {$wpdb->options} WHERE option_name=%s AND option_value=%s",
            self::OPTION,
            maybe_serialize($current)
        )); // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
        if ($deleted) {
            wp_cache_delete(self::OPTION, 'options');
        }
    }

    public static function diagnostics(): array
    {
        $current = get_option(self::OPTION, []);
        if (!is_array($current) || (int) ($current['expires'] ?? 0) < time()) {
            return ['locked' => false];
        }
        return [
            'locked' => true,
            'owner' => (string) ($current['owner'] ?? 'unknown'),
            'expires_at' => gmdate('c', (int) $current['expires']),
        ];
    }
}