<?php
namespace JVBase\managers\queue;
if (!defined('ABSPATH')) {
	exit;
}

class Locker
{
	private string $lockKey;
	private int $ttl;
	private ?string $token = null;

	public function __construct(string $key = 'queue_processor', int $ttl = 300)
	{
		$this->lockKey = BASE . '_lock_' . $key;
		$this->ttl = $ttl;
	}

	public function acquire(): bool
	{
		// Generate unique token for this process
		$this->token = uniqid(gethostname() . '_', true);

		// SET NX with TTL - atomic "set if not exists"
		$result = wp_cache_add($this->lockKey, $this->token, 'locks', $this->ttl);

		return $result === true;
	}

	public function release(): void
	{
		if (!$this->token) {
			return;
		}

		// Only release if we own the lock
		$current = wp_cache_get($this->lockKey, 'locks');
		if ($current === $this->token) {
			wp_cache_delete($this->lockKey, 'locks');
		}

		$this->token = null;
	}

	public function isLocked(): bool
	{
		return wp_cache_get($this->lockKey, 'locks') !== false;
	}

	/**
	 * Execute callback with lock, auto-release after
	 */
	public function withLock(callable $callback): mixed
	{
		if (!$this->acquire()) {
			return null;
		}

		try {
			return $callback();
		} finally {
			$this->release();
		}
	}
}