<?php

/*
 * This file is part of Phraseanet
 *
 * (c) 2005-2013 Alchemy
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

use Alchemy\Phrasea\Application;

/**
 * UpgradeManager for Phraseanet.
 * Datas are written in a lock file.
 * If lock file exists, it contains YAML datas about the current process.
 *
 * @package     Setup
 * @license     http://opensource.org/licenses/gpl-3.0 GPLv3
 * @link        www.phraseanet.com
 */
class Setup_Upgrade
{
    /**
     *
     * @var appbox
     */
    protected $appbox;

    /**
     *
     * @var string
     */
    protected $message;

    /**
     *
     * @var array
     */
    protected $recommendations = array();

    /**
     *
     * @var int
     */
    protected $total_steps = 0;

    /**
     *
     * @var int
     */
    protected $completed_steps = 0;

    public function __construct(Application $app, $force = false)
    {
        if ($force) {
            self::remove_lock_file();
        }

        if (self::lock_exists()) {
            throw new Exception_Setup_UpgradeAlreadyStarted('The upgrade is already started');
        }

        $this->appbox = $app['phraseanet.appbox'];

        if (count(User_Adapter::get_wrong_email_users($app)) > 0) {
            throw new Exception_Setup_FixBadEmailAddresses('Please fix the database before starting');
        }

        $this->write_lock();

        return $this;
    }

    /**
     *
     * @return Void
     */
    public function __destruct()
    {
        self::remove_lock_file();

        return;
    }

    /**
     * Add steps to do to the counter
     *
     * @param  int           $how_many
     * @return Setup_Upgrade
     */
    public function add_steps($how_many)
    {
        $this->total_steps += (int) $how_many;
        $this->write_lock();

        return $this;
    }

    /**
     * Add completed steps to the counter
     *
     * @param  int           $how_many
     * @return Setup_Upgrade
     */
    public function add_steps_complete($how_many)
    {
        $this->completed_steps += (int) $how_many;
        $this->write_lock();

        return $this;
    }

    /**
     * Set the current message
     *
     * @param  string        $message
     * @return Setup_Upgrade
     */
    public function set_current_message($message)
    {
        $this->message = $message;
        $this->write_lock();

        return $this;
    }

    /**
     *
     * @param type $recommendation
     * @param type $command
     */
    public function addRecommendation($recommendation, $command = null)
    {
        $this->recommendations[] = array($recommendation, $command);
    }

    /**
     * Return an array of recommendations
     *
     * @return array
     */
    public function getRecommendations()
    {
        return $this->recommendations;
    }

    /**
     *
     * @return float
     */
    protected function get_percentage()
    {
        if ($this->total_steps === 0) {
            return 1;
        }

        return round(max(min(($this->completed_steps / $this->total_steps), 1), 0), 2);
    }

    /**
     *
     *
     * @return Setup_Upgrade
     */
    protected function write_lock()
    {
        $date_obj = new DateTime();
        $dumper = new Symfony\Component\Yaml\Dumper();
        $datas = $dumper->dump(
            array(
            'percentage'      => $this->get_percentage()
            , 'total_steps'     => $this->total_steps
            , 'completed_steps' => $this->completed_steps
            , 'message'         => $this->message
            , 'last_update'     => $date_obj->format(DATE_ATOM)
            ), 1
        );

        if (!file_put_contents(self::get_lock_file(), $datas))
            throw new Exception_Setup_CannotWriteLockFile(
                sprintf('Cannot write lock file to %s', self::get_lock_file())
            );

        return $this;
    }

    /**
     * Returns true if the file exists
     *
     * @return boolean
     */
    protected static function lock_exists()
    {
        clearstatcache();

        return file_exists(self::get_lock_file());
    }

    /**
     * Return the path fil to the lock file
     *
     * @return string
     */
    public static function get_lock_file()
    {
        return __DIR__ . '/../../../tmp/upgrade.lock';
    }

    /**
     *
     * @return Void
     */
    protected static function remove_lock_file()
    {
        if (self::lock_exists()) {
            unlink(self::get_lock_file());
        }

        return;
    }

    /**
     *
     * Returns an array containing datas about the Upgrade Status.
     * Contains the following keys :
     *  - active          : (booolean) tells if there's a current upgrade
     *  - percentage      : (float) a number between 0 and 1 of the current progress
     *  - total_steps     : (int) total steps
     *  - completed_steps : (int) current complete steps
     *  - message         : (string) a message
     *  - last_update     : (string) last update in ATOM format
     *
     *
     * @return Array
     */
    public static function get_status()
    {
        $active = self::lock_exists();

        $datas = array(
            'active'          => $active
            , 'percentage'      => 1
            , 'total_steps'     => 0
            , 'completed_steps' => 0
            , 'message'         => null
            , 'last_update'     => null
        );

        if ($active) {
            $parser = new Symfony\Component\Yaml\Parser();
            $datas = array_merge(
                $datas
                , $parser->parse(file_get_contents(self::get_lock_file()))
            );
        }

        return $datas;
    }
}