<?php
/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2020 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
 * Website: https://www.espocrm.com
 *
 * EspoCRM is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * EspoCRM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
 ************************************************************************/

namespace Espo\Core;

use PDO;

use Espo\Core\{
    ServiceFactory,
    InjectableFactory,
    Utils\Config,
    Utils\File\Manager as FileManager,
    Utils\Json,
    Utils\System,
    Utils\ScheduledJob,
    Utils\Cron\ScheduledJob as CronScheduledJob,
    Utils\Cron\Job as CronJob,
    ORM\EntityManager,
};

use Espo\Entities\Job as JobEntity;

use Spatie\Async\Pool as AsyncPool;

use Espo\Core\Exceptions\NotFound;
use Espo\Core\Exceptions\Error;

class CronManager
{
    private $cronJobUtil;

    private $cronScheduledJobUtil;

    private $useProcessPool = false;

    private $asSoonAsPossibleSchedulingList = [
        '*',
        '* *',
        '* * *',
        '* * * *',
        '* * * * *',
        '* * * * * *',
    ];

    const PENDING = 'Pending';

    const READY = 'Ready';

    const RUNNING = 'Running';

    const SUCCESS = 'Success';

    const FAILED = 'Failed';

    protected $lastRunTime = 'data/cache/application/cronLastRunTime.php';

    protected $config;
    protected $fileManager;
    protected $entityManager;
    protected $serviceFactory;
    protected $injectableFactory;
    protected $scheduledJob;

    public function __construct(
        Config $config,
        FileManager $fileManager,
        EntityManager $entityManager,
        ServiceFactory $serviceFactory,
        InjectableFactory $injectableFactory,
        ScheduledJob $scheduledJob
    ) {
        $this->config = $config;
        $this->fileManager = $fileManager;
        $this->entityManager = $entityManager;
        $this->serviceFactory = $serviceFactory;
        $this->injectableFactory = $injectableFactory;
        $this->scheduledJob = $scheduledJob;

        $this->cronJobUtil = new CronJob($this->config, $this->entityManager);
        $this->cronScheduledJobUtil = new CronScheduledJob($this->config, $this->entityManager);

        if ($this->config->get('jobRunInParallel')) {
            if (AsyncPool::isSupported()) {
                $this->useProcessPool = true;
            } else {
                $GLOBALS['log']->warning("CronManager: useProcessPool requires pcntl and posix extensions.");
            }
        }
    }

    protected function getScheduledJobUtil()
    {
        return $this->scheduledJob;
    }

    protected function getCronJobUtil()
    {
        return $this->cronJobUtil;
    }

    protected function getCronScheduledJobUtil()
    {
        return $this->cronScheduledJobUtil;
    }

    protected function getLastRunTime()
    {
        $lastRunData = $this->fileManager->getPhpContents($this->lastRunTime);

        if (is_array($lastRunData) && !empty($lastRunData['time'])) {
            $lastRunTime = $lastRunData['time'];
        } else {
            $lastRunTime = time() - intval($this->config->get('cronMinInterval', 0)) - 1;
        }

        return $lastRunTime;
    }

    protected function setLastRunTime($time)
    {
        $data = array(
            'time' => $time,
        );
        return $this->fileManager->putPhpContents($this->lastRunTime, $data);
    }

    protected function checkLastRunTime()
    {
        $currentTime = time();
        $lastRunTime = $this->getLastRunTime();
        $cronMinInterval = $this->config->get('cronMinInterval', 0);

        if ($currentTime > ($lastRunTime + $cronMinInterval)) {
            return true;
        }

        return false;
    }

    protected function useProcessPool()
    {
        return $this->useProcessPool;
    }

    public function setUseProcessPool(bool $useProcessPool)
    {
        $this->useProcessPool = $useProcessPool;
    }

    /**
     * Run cron.
     */
    public function run()
    {
        if (!$this->checkLastRunTime()) {
            $GLOBALS['log']->info('CronManager: Stop cron running, too frequent execution.');
            return;
        }

        $this->setLastRunTime(time());

        $this->getCronJobUtil()->markJobsFailed();
        $this->getCronJobUtil()->updateFailedJobAttempts();
        $this->createJobsFromScheduledJobs();
        $this->getCronJobUtil()->removePendingJobDuplicates();

        $this->processPendingJobs();
    }

    /**
     * Run a portion of pending jobs.
     */
    public function processPendingJobs($queue = null, $limit = null, $poolDisabled = false, $noLock = false)
    {
        if (is_null($limit)) {
            $limit = intval($this->config->get('jobMaxPortion', 0));
        }

        $pendingJobList = $this->getCronJobUtil()->getPendingJobList($queue, $limit);

        $useProcessPool = $this->useProcessPool();

        if ($poolDisabled) {
            $useProcessPool = false;
        }

        if ($useProcessPool) {
            $pool = \Spatie\Async\Pool::create()
                ->autoload(getcwd() . '/vendor/autoload.php')
                ->concurrency($this->config->get('jobPoolConcurrencyNumber'))
                ->timeout($this->config->get('jobPeriodForActiveProcess'));
        }

        foreach ($pendingJobList as $job) {
            $skip = false;
            if (!$noLock) $this->lockJobTable();
            if ($noLock || $this->getCronJobUtil()->isJobPending($job->id)) {
                if ($job->get('scheduledJobId')) {
                    if ($this->getCronJobUtil()->isScheduledJobRunning(
                        $job->get('scheduledJobId'), $job->get('targetId'), $job->get('targetType'))
                    ) {
                        $skip = true;
                    }
                }
            } else {
                $skip = true;
            }

            if ($skip) {
                if (!$noLock) $this->unlockTables();
                continue;
            }

            $job->set('startedAt', date('Y-m-d H:i:s'));

            if ($useProcessPool) {
                $job->set('status', self::READY);
            } else {
                $job->set('status', self::RUNNING);
                $job->set('pid', \Espo\Core\Utils\System::getPid());
            }

            $this->entityManager->saveEntity($job);
            if (!$noLock) $this->unlockTables();

            if ($useProcessPool) {
                $task = new \Espo\Core\Utils\Cron\JobTask($job->id);
                $pool->add($task);
            } else {
                $this->runJob($job);
            }
        }

        if ($useProcessPool) {
            $pool->wait();
        }
    }

    protected function lockJobTable()
    {
        $this->entityManager->getPDO()->query('LOCK TABLES `job` WRITE');
    }

    protected function unlockTables()
    {
        $this->entityManager->getPDO()->query('UNLOCK TABLES');
    }

    /**
     * Run a specific job by ID. A job status should be set to 'Ready'.
     */
    public function runJobById(string $id)
    {
        if (empty($id)) throw new Error();

        $job = $this->entityManager->getEntity('Job', $id);

        if (!$job) throw new Error("Job {$id} not found.");

        if ($job->get('status') !== self::READY) {
            throw new Error("Can't run job {$id} with no status Ready.");
        }

        if (!$job->get('startedAt')) {
            $job->set('startedAt', date('Y-m-d H:i:s'));
        }

        $job->set('status', self::RUNNING);
        $job->set('pid',System::getPid());
        $this->entityManager->saveEntity($job);

        $this->runJob($job);
    }

    /**
     * Run a specific job.
     */
    public function runJob(JobEntity $job)
    {
        $isSuccess = true;
        $skipLog = false;

        try {
            if ($job->get('scheduledJobId')) {
                $this->runScheduledJob($job);
            } else if ($job->get('job')) {
                $this->runJobByName($job);
            } else {
                $this->runService($job);
            }
        } catch (\Throwable $e) {
            $isSuccess = false;
            if ($e->getCode() === -1) {
                $job->set('attempts', 0);
                $skipLog = true;
            } else {
                $GLOBALS['log']->error(
                    'CronManager: Failed job running, job ['. $job->id .']. Error Details: '.
                    $e->getMessage() .' at '. $e->getFile() . ':' . $e->getLine()
                );
            }
        }

        $status = $isSuccess ? self::SUCCESS : self::FAILED;

        $job->set('status', $status);

        if ($isSuccess) {
            $job->set('executedAt', date('Y-m-d H:i:s'));
        }

        $this->entityManager->saveEntity($job);

        if ($job->get('scheduledJobId') && !$skipLog) {
            $this->getCronScheduledJobUtil()->addLogRecord(
                $job->get('scheduledJobId'), $status, null, $job->get('targetId'), $job->get('targetType')
            );
        }

        if ($isSuccess) return true;
        return false;
    }

    protected function runScheduledJob(JobEntity $job)
    {
        $jobName = $job->get('scheduledJobJob');

        $className = $this->getScheduledJobUtil()->getJobClassName($jobName);

        if ($className === false) throw new Error("No class name for job {$jobName}.");

        $obj = $this->injectableFactory->create($className);

        if (!method_exists($obj, 'run')) throw new Error("No 'run' method in job {$jobName}.");

        $data = null;
        if ($job->get('data')) {
            $data = $job->get('data');
        }

        $obj->run($data, $job->get('targetId'), $job->get('targetType'));
    }

    protected function runService(JobEntity $job)
    {
        $serviceName = $job->get('serviceName');

        if (!$serviceName) {
            throw new Error("Job with empty serviceName.");
        }

        if (!$this->serviceFactory->checkExists($serviceName)) throw new Error();

        $service = $this->serviceFactory->create($serviceName);

        $methodNameDeprecated = $job->get('method');
        $methodName = $job->get('methodName');

        if (!$methodName) throw new Error('Job with empty methodName.');

        if (!method_exists($service, $methodName)) throw new Error();

        $data = $job->get('data');

        $service->$methodName($data, $job->get('targetId'), $job->get('targetType'));
    }

    protected function runJobByName(JobEntity $job)
    {
        $jobName = $job->get('job');

        $className = $this->getScheduledJobUtil()->getJobClassName($jobName);

        if ($className === false) throw new Error("No class name for job {$jobName}.");

        $obj = $this->injectableFactory->create($className);
        if (!method_exists($obj, 'run')) throw new Error("No 'run' method in job {$jobName}.");

        $data = $job->get('data') ?: null;

        $obj->run($data, $job->get('targetId'), $job->get('targetType'));
    }

    protected function createJobsFromScheduledJobs()
    {
        $activeScheduledJobList = $this->getCronScheduledJobUtil()->getActiveScheduledJobList();
        $runningScheduledJobIdList = $this->getCronJobUtil()->getRunningScheduledJobIdList();

        $createdJobIdList = [];
        foreach ($activeScheduledJobList as $scheduledJob) {
            $scheduling = $scheduledJob->get('scheduling');
            $asSoonAsPossible = in_array($scheduling, $this->asSoonAsPossibleSchedulingList);

            if ($asSoonAsPossible) {
                $nextDate = date('Y-m-d H:i:s');
            } else {
                try {
                    $cronExpression = \Cron\CronExpression::factory($scheduling);
                } catch (\Exception $e) {
                    $GLOBALS['log']->error(
                        'CronManager (ScheduledJob ['.$scheduledJob->id.']): Scheduling string error - '. $e->getMessage() . '.'
                    );
                    continue;
                }

                try {
                    $nextDate = $cronExpression->getNextRunDate()->format('Y-m-d H:i:s');
                } catch (\Exception $e) {
                    $GLOBALS['log']->error(
                        'CronManager (ScheduledJob ['.$scheduledJob->id.']): Unsupported CRON expression ['.$scheduling.']'
                    );
                    continue;
                }

                $jobAlreadyExists = $this->getCronJobUtil()->hasScheduledJobOnMinute($scheduledJob->id, $nextDate);
                if ($jobAlreadyExists) {
                    continue;
                }
            }

            $className = $this->getScheduledJobUtil()->getJobClassName($scheduledJob->get('job'));
            if ($className) {
                if (method_exists($className, 'prepare')) {
                    $obj = $this->injectableFactory->create($className);
                    $obj->prepare($scheduledJob, $nextDate);
                    continue;
                }
            }

            if (in_array($scheduledJob->id, $runningScheduledJobIdList)) {
                continue;
            }

            $pendingCount = $this->getCronJobUtil()->getPendingCountByScheduledJobId($scheduledJob->id);

            if ($asSoonAsPossible) {
                if ($pendingCount > 0) {
                    continue;
                }
            } else {
                if ($pendingCount > 1) {
                    continue;
                }
            }

            $jobEntity = $this->entityManager->getEntity('Job');
            $jobEntity->set([
                'name' => $scheduledJob->get('name'),
                'status' => self::PENDING,
                'scheduledJobId' => $scheduledJob->id,
                'executeTime' => $nextDate
            ]);
            $this->entityManager->saveEntity($jobEntity);
        }
    }
}