<?php

declare(strict_types=1);

namespace App\Services\Crawler;

use App\Models\CrawlRule;
use Carbon\CarbonImmutable;
use Cron\CronExpression;

class CrawlRuleScheduleService
{
    public function isDue(CrawlRule $rule, ?CarbonImmutable $now = null): bool
    {
        if (! $rule->enabled) {
            return false;
        }

        $now ??= CarbonImmutable::now($rule->timezone ?: 'Asia/Shanghai');

        try {
            $cron = new CronExpression($rule->cron_expression);
        } catch (\Throwable) {
            return false;
        }

        return $cron->isDue($now);
    }

    public function nextRunAt(CrawlRule $rule, ?CarbonImmutable $from = null): ?CarbonImmutable
    {
        $from ??= CarbonImmutable::now($rule->timezone ?: 'Asia/Shanghai');

        try {
            $cron = new CronExpression($rule->cron_expression);
            $next = CarbonImmutable::instance($cron->getNextRunDate($from));
        } catch (\Throwable) {
            return null;
        }

        return $next->setTimezone('UTC');
    }
}