<?php

namespace BRSystems\Core\Library\cProcess;

use BRSystems\Core\Library\cApc\cApc;

/**
 * CMS/APP cProcess class
 *
 * @category LIB cProcess
 * @author Mareks Keišs <mareks.keiss@brsystems.lv>
 * @since Version 1.0
 *
 * Writes the $_SESSION content to disk and relinquishes the lock.
 * After starting a new process automatically locks session - writing to $_SESSION will result in loss of data
 */
class cProcess
{
    public $oApc;

    private $sProcessId;
    private $bUseSession;
    private $bSessionClosed = false;

    const PROCESS_SESSION_KEY = 'session_processes';

    const PROCESS_STATUS_ACTIVE = 'active';
    const PROCESS_STATUS_ABORTED = 'aborted';
    const PROCESS_STATUS_EXPIRED = 'expired';
    const PROCESS_STATUS_FINISHED = 'finished';

    const KEY_PROGRESS = 'progress';
    const KEY_PROGRESS_MSG = 'progressMsg';
    const KEY_PROGRESS_STATUS = 'processStatus';

    private $iProgressStep = 0;
    private $iCurrentProgressVal = 0;

    /**
     * Class constructor
     * @param string|boolean $sProcessId - passed process id
     * @param boolean $bStartProcess - start new process by the given id
     * @param boolean $bUseSession - use session as data conduit
     * @param cApc|boolean $oApc - cache APC object
     */
    public function __construct($sProcessId = false, $bStartProcess = true, $bUseSession = true, &$oApc = false){

        $this->oApc = $oApc;
        $this->sProcessId = $sProcessId;
        $this->bUseSession = $bUseSession;


        if($sProcessId && $bStartProcess)
            $this->startProcess($sProcessId);

    }

    /**
     * Function to relinquish session for other process request to use
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     *
     * @return void
     */
    public function closeSession(){

        if($this->bUseSession && !$this->bSessionClosed){
            // Writes the $_SESSION content to disk and relinquishes the lock.
            // After this writing to $_SESSION will result in loss of data
            session_write_close();
            $this->bSessionClosed = true;
        }

    }

    /**
     * Function to restart session for this process request to use
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     *
     * @return void
     */
    public function restartSession(){

        if($this->bUseSession && $this->bSessionClosed){
            unset($_SESSION);
            startSessionSameSite(60*60*24);
            $this->bSessionClosed = false;
        }

    }

    /**
     * Function to start new process
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string $sProcessId - process id
     * @param array $vData
     * @param int $iTTL - tile to live by default 60*20
     * @return bool
     */
    public function startProcess($sProcessId, $vData = array(), $iTTL = 1200){

        $vSaveData = array(
            'startTime' => date('d.m.Y H:i:s'),
            'startTimeUnix' => time(),
            self::KEY_PROGRESS => 0,
            self::KEY_PROGRESS_MSG => '',
            self::KEY_PROGRESS_STATUS => self::PROCESS_STATUS_ACTIVE,
            'ttl' => $iTTL,
        );
        // Add additional data
        if(!!$vData) $vSaveData = $vData + $vSaveData;

        if($this->bUseSession){
            $_SESSION[self::PROCESS_SESSION_KEY][$sProcessId] = $vSaveData;
            $this->closeSession();
        }else
            $this->oApc->store("P_{$sProcessId}", $vSaveData, $iTTL);

        return true;
    }

    /**
     * Function to start update process
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sProcessId - process id
     * @param array $vData
     * @param int $iTTL - tile to live by default 60*20
     * @return bool
     */
    public function updateProcess($sProcessId = false, $vData, $iTTL = 1200){

        $sProcessId = ($sProcessId ? $sProcessId : $this->sProcessId);

        if(!!$vData){
            if($this->bUseSession){
                $this->restartSession();
                if(isset($_SESSION[self::PROCESS_SESSION_KEY][$sProcessId])){
                    $_SESSION[self::PROCESS_SESSION_KEY][$sProcessId] = $vData + $_SESSION[self::PROCESS_SESSION_KEY][$sProcessId];
                }
                $this->closeSession();
                return true;
            }else{
                if($this->oApc->exists("P_{$sProcessId}") && !!$vData){
                    $vProcessData = $this->oApc->check("P_{$sProcessId}");
                    $vProcessData = $vData + $vProcessData;
                    $this->oApc->store("P_{$sProcessId}", $vProcessData, $iTTL);
                    return true;
                }
            }
        }

        return false;
    }

    /**
     * Function to get process data
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sProcessId - process id
     * @return mixed
     */
    public function getProcess($sProcessId = false){

        $sProcessId = ($sProcessId ? $sProcessId : $this->sProcessId);

        if($this->bUseSession){
            $this->restartSession();
            if(isset($_SESSION[self::PROCESS_SESSION_KEY][$sProcessId])){
                $this->closeSession();
                return $_SESSION[self::PROCESS_SESSION_KEY][$sProcessId];
            }
        }else{
            if($this->oApc->exists("P_{$sProcessId}")){
                return $this->oApc->check("P_{$sProcessId}");
            }
        }
        return false;
    }

    /**
     * Function to abort process
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sProcessId - process id
     * @return mixed
     */
    public function abortProcess($sProcessId = false){

        return $this->updateProcess(array('processStatus' => self::PROCESS_STATUS_ABORTED), $sProcessId);

    }

    /**
     * Function to destroy process
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sProcessId - process id
     * @return mixed
     */
    public function destroyProcess($sProcessId = false){

        $sProcessId = ($sProcessId ? $sProcessId : $this->sProcessId);

        if($this->bUseSession){
            $this->restartSession();
            unset($_SESSION[self::PROCESS_SESSION_KEY][$sProcessId]);
            $this->closeSession();
        }else
            $this->oApc->setExpired("P_{$sProcessId}");

        return true;
    }

    /**
     * Function to check if process aborted process
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sProcessId - process id
     * @return mixed
     */
    public function chkProcessAbortStatus($sProcessId = false){

        $vProcess = $this->getProcess($sProcessId);
        if($vProcess && !empty($vProcess['processStatus']) && $vProcess['processStatus'] == self::PROCESS_STATUS_ABORTED) return true;
        return false;

    }

    /**
     * Function to update process progress value & msg
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param int|boolean $iPercent - process percent progress
     * @param string|boolean $sMsg - process progress message
     * @param string|boolean $sProcessId - process id
     * @return mixed
     */
    public function updProcessProgress($iPercent = false, $sMsg = false, $sProcessId = false){

        $vUpdateData = array();
        if(!!$iPercent) $vUpdateData[self::KEY_PROGRESS] = number_format($iPercent);
        if(!!$sMsg) $vUpdateData[self::KEY_PROGRESS_MSG] = $sMsg;

        if(!!$vUpdateData)$this->updateProcess($sProcessId, $vUpdateData);
        return false;

    }

    /**
     * Convenience Function to calculate & set progress step based upon passed iteration count
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param int|boolean $iIterations - iterations to 100%
     * @param int $iMaxPercentagePerStep - maximum allowed percentage
     * @return void
     */
    public function setProcessProgressStep($iIterations = false, $iMaxPercentagePerStep = 100){
        if(!!$iIterations){
            if($iMaxPercentagePerStep < 0 || $iMaxPercentagePerStep > 100) $iMaxPercentagePerStep = 100;
            $this->iProgressStep = $iMaxPercentagePerStep / $iIterations;
            $this->iCurrentProgressVal = 0;
        }
    }

    /**
     * Convenience Function to calculate & update progress based upon next step
     *
     * @author Mareks Keišs <mareks.keiss@brsystems.lv>
     * @category pubDocuments Controller
     * @param string|boolean $sMsg - process progress message
     * @return void
     */
    public function updProcessProgressByStep($sMsg = false){
        if(!!$this->iProgressStep){
            $this->iCurrentProgressVal += $this->iProgressStep;
            if($this->iCurrentProgressVal > 100) $this->iCurrentProgressVal = 100;
        }

        $this->updProcessProgress($this->iCurrentProgressVal, $sMsg);
    }
}