<?php
/************************************************************************
 * This file is part of EspoCRM.
 *
 * EspoCRM - Open Source CRM application.
 * Copyright (C) 2014-2015 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
 * Website: http://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/.
 ************************************************************************/

namespace Espo\Core\Utils\Cron;

use \PDO;
use \Espo\Core\CronManager;
use \Espo\Core\Utils\Config;
use \Espo\Core\ORM\EntityManager;

class Job
{
    private $config;

    private $entityManager;

    private $cronScheduledJob;

    public function __construct(Config $config, EntityManager $entityManager)
    {
        $this->config = $config;
        $this->entityManager = $entityManager;

        $this->cronScheduledJob = new ScheduledJob($this->config, $this->entityManager);
    }

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

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

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

    /**
     * Get Pending Jobs
     *
     * @return array
     */
    public function getPendingJobs()
    {
        /** Mark Failed old jobs and remove pending duplicates */
        $this->markFailedJobs();
        $this->markJobAttempts();
        $this->removePendingJobDuplicates();

        $jobList = $this->getActiveJobs();

        $runningScheduledJobs = $this->getActiveJobs('scheduled_job_id', CronManager::RUNNING, PDO::FETCH_COLUMN);

        $list = array();
        foreach ($jobList as $row) {
            if (!in_array($row['scheduled_job_id'], $runningScheduledJobs)) {
                $list[] = $row;
            }
        }

        return $list;
    }

    /**
     * Get active Jobs, which execution date in jobPeriod time
     *
     * @param  string $displayColumns
     * @param  string $status
     *
     * @return array
     */
    public function getActiveJobs($displayColumns = '*', $status = CronManager::PENDING, $fetchMode = PDO::FETCH_ASSOC)
    {
        $jobConfigs = $this->getConfig()->get('cron');

        $currentTime = time();
        $limit = empty($jobConfigs['maxJobNumber']) ? '' : 'LIMIT '.$jobConfigs['maxJobNumber'];

        $query = "SELECT " . $displayColumns . " FROM job WHERE
                    `status` = '" . $status . "'
                    AND execute_time <= '".date('Y-m-d H:i:s', $currentTime)."'
                    AND deleted = 0
                    ORDER BY execute_time ASC ".$limit;

        $pdo = $this->getEntityManager()->getPDO();
        $sth = $pdo->prepare($query);
        $sth->execute();

        $rows = $sth->fetchAll($fetchMode);

        return $rows;
    }

    /**
     * Get Jobs by ScheduledJobId and date
     *
     * @param  string $scheduledJobId
     * @param  string $time
     *
     * @return array
     */
    public function getJobByScheduledJob($scheduledJobId, $time)
    {
        $dateObj = new \DateTime($time);
        $timeWithoutSeconds = $dateObj->format('Y-m-d H:i:');

        $query = "SELECT * FROM job WHERE
                    scheduled_job_id = '".$scheduledJobId."'
                    AND execute_time LIKE '".$timeWithoutSeconds."%'
                    AND deleted = 0
                    LIMIT 1";

        $pdo = $this->getEntityManager()->getPDO();
        $sth = $pdo->prepare($query);
        $sth->execute();

        $scheduledJob = $sth->fetchAll(PDO::FETCH_ASSOC);

        return $scheduledJob;
    }

    /**
     * Mark pending jobs (all jobs that exceeded jobPeriod)
     *
     * @return void
     */
    protected function markFailedJobs()
    {
        $jobConfigs = $this->getConfig()->get('cron');

        $currentTime = time();
        $periodTime = $currentTime - intval($jobConfigs['jobPeriod']);

        $pdo = $this->getEntityManager()->getPDO();

        $select = "SELECT id, scheduled_job_id, execute_time FROM `job` WHERE
                    (`status` = '" . CronManager::RUNNING ."')
                    AND execute_time < '".date('Y-m-d H:i:s', $periodTime)."' ";
        $sth = $pdo->prepare($select);
        $sth->execute();

        $jobData = array();
        while ($row = $sth->fetch(PDO::FETCH_ASSOC)){
           $jobData[$row['id']] = $row;
        }

        $update = "UPDATE job SET `status` = '". CronManager::FAILED ."' WHERE id IN ('".implode("', '", array_keys($jobData))."')";
        $sth = $pdo->prepare($update);
        $sth->execute();

        //add status 'Failed' to SchediledJobLog
        $cronScheduledJob = $this->getCronScheduledJob();
        foreach ($jobData as $jobId => $job) {
            if (!empty($job['scheduled_job_id'])) {
                $cronScheduledJob->addLogRecord($job['scheduled_job_id'], CronManager::FAILED, $job['execute_time']);
            }
        }
    }

    /**
     * Remove pending duplicate jobs, no need to run twice the same job
     *
     * @return void
     */
    protected function removePendingJobDuplicates()
    {
        $pdo = $this->getEntityManager()->getPDO();

        $query = "SELECT scheduled_job_id FROM job
                    WHERE
                    scheduled_job_id IS NOT NULL
                    AND `status` = '".CronManager::PENDING."'
                    AND execute_time <= '".date('Y-m-d H:i:s')."'
                    AND deleted = 0
                    GROUP BY scheduled_job_id
                    HAVING count( * ) > 1
                    ORDER BY execute_time ASC";
        $sth = $pdo->prepare($query);
        $sth->execute();

        $duplicateJobs = $sth->fetchAll(PDO::FETCH_ASSOC);

        foreach ($duplicateJobs as $row) {
            if (!empty($row['scheduled_job_id'])) {

                /* no possibility to use limit in update or subqueries */
                $query = "SELECT id FROM `job` WHERE scheduled_job_id = '" . $row['scheduled_job_id'] . "'
                            AND `status` = '" . CronManager::PENDING ."'
                            ORDER BY execute_time
                            DESC LIMIT 1, 100000 ";
                $sth = $pdo->prepare($query);
                $sth->execute();
                $jobIds = $sth->fetchAll(PDO::FETCH_COLUMN);

                $update = "UPDATE job SET deleted = 1 WHERE
                            id IN ('". implode("', '", $jobIds)."') ";

                $sth = $pdo->prepare($update);
                $sth->execute();
            }
        }
    }

    /**
     * Mark job attempts
     *
     * @return void
     */
    protected function markJobAttempts()
    {
        $query = "SELECT * FROM job WHERE
                    `status` = '" . CronManager::FAILED . "'
                    AND deleted = 0
                    AND execute_time <= '".date('Y-m-d H:i:s')."'
                    AND attempts > 0";

        $pdo = $this->getEntityManager()->getPDO();
        $sth = $pdo->prepare($query);
        $sth->execute();

        $rows = $sth->fetchAll(PDO::FETCH_ASSOC);
        if ($rows) {
            foreach ($rows as $row) {
                $row['failed_attempts'] = isset($row['failed_attempts']) ? $row['failed_attempts'] : 0;

                $attempts = $row['attempts'] - 1;
                $failedAttempts = $row['failed_attempts'] + 1;

                $update = "UPDATE job SET
                            `status` = '" . CronManager::PENDING ."',
                            attempts = '".$attempts."',
                            failed_attempts = '".$failedAttempts."'
                            WHERE
                            id = '".$row['id']."'
                ";
                $pdo->prepare($update)->execute();
            }
        }
    }
}