<?php
# Lifter002: TEST
# Lifter007: TODO
# Lifter003: TODO
# Lifter010: TODO
// +--------------------------------------------------------------------------+
// This file is part of Stud.IP
// Copyright (C) 2001-2004 Stud.IP
// +--------------------------------------------------------------------------+
// This program 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 2
// of the License, or any later version.
// +--------------------------------------------------------------------------+
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// +--------------------------------------------------------------------------+


# Include all required files ================================================ #
require_once 'lib/evaluation/evaluation.config.php';
require_once 'lib/export/export_tmp_gc.inc.php';
require_once EVAL_FILE_EVALDB;
require_once EVAL_FILE_ANSWERDB;
require_once EVAL_FILE_OBJECT;
require_once EVAL_FILE_GROUP;

/**
 * @const INSTANCEOF_EVALEXPORTMANAGER Is instance of an export manager
 * @access public
 */
define("INSTANCEOF_EVALEXPORTMANAGER", "EvaluationExportManager");

/**
 * @const EVALEXPORT_PREFIX The prefix for temporary filenames
 * @access public
 */
define("EVALEXPORT_PREFIX", "evaluation");

/**
 * @const EVALEXPORT_LIFETIME The lifetime in seconds for temporary files
 * @access public
 */
define("EVALEXPORT_LIFETIME", 1800);


/**
 * The mainclass for the evaluation export manager
 *
 * @author  Alexander Willner <mail@AlexanderWillner.de>
 *
 * @copyright   2004 Stud.IP-Project
 * @access      public
 * @package     evaluation
 *
 */
class EvaluationExportManager extends AuthorObject
{

    /**
     * The temporary filename
     * @access   private
     * @var      string $filename
     */
    public $filename;

    /**
     * The filehandle for the temporary filename
     * @access   private
     * @public      integer $filehandle
     */
    public $filehandle;

    /**
     * The ID for the evaluation to export
     * @access   private
     * @var      string $evalID
     */
    public $evalID;

    /**
     * The evaluation to export
     * @access   private
     * @var      object   Evaluation   $eval
     */
    public $eval;

    /**
     * Array full of questionobjects
     * @access   private
     * @var      array $evalquestions
     */
    public $evalquestions;

    /**
     * The extension for the FILENAME
     * @access   private
     * @var      string $extension
     */
    public $extension;

    /**
     * UserIDs of all persons which used the evaluation
     * @access   private
     * @var      array $users
     */
    public $users;

    /**
     * Constructor
     * @access   public
     * @param string $evalID The ID of the evaluation for export
     */
    public function __construct($evalID)
    {
        register_shutdown_function([&$this, "_EvaluationExportManager"]);

        parent::__construct();
        $this->instanceof = INSTANCEOF_EVALEXPORTMANAGER;

        $this->filename = "";
        $this->filehandle = "";
        $this->evalID = $evalID;
        $this->eval = new Evaluation ($evalID, NULL, EVAL_LOAD_FIRST_CHILDREN);
        $this->evalquestions = [];
        $this->extension = EVALEXPORT_EXTENSION;

        $this->createNewFile();
        $this->getQuestionobjects($this->eval);
        /* -------------------------------------------------------------------- */
    }

    /**
     * Destructor. Closes all files and removes old temp files
     * @access   public
     */
    public function _EvaluationExportManager()
    {
        $this->closeFile();
        $this->cleanUp();
    }

    /**
     * Returns the temnporary filename
     * @access   public
     * @returns  string   The temporary filename
     */
    public function getTempFilename()
    {
        return $this->filename;
    }

    /**
     * Exports the evaluation
     * @access   public
     */
    public function export()
    {
        if (empty ($this->filehandle)) {
            return $this->throwError(1, _("ExportManager::Konnte temporäre Datei nicht öffnen."));
        }

        if (!$this->eval->isAnonymous()) {
            $this->users = EvaluationDB::getUserVoted($this->eval->getObjectID());
        } else {
            $questions = $this->eval->getSpecialChildobjects($this->eval, INSTANCEOF_EVALQUESTION);
            $questionIDs = [];
            foreach ($questions as $question) {
                array_push($questionIDs, $question->getObjectID());
            }
            $this->users = EvaluationDB::getUserVoted($this->eval->getObjectID(), null, $questionIDs);
        }

        if (empty ($this->users)) {
            return $this->throwError(1, _("ExportManager::Es haben noch keine Benutzer abgestimmt oder angegebene Evaluation existiert nicht."));
        }
    }

    /**
     * Gets the filname for the user
     * @access   public
     */
    public function getFilename()
    {
        return (rawurlencode($this->eval->getTitle()) . "." . $this->extension);
    }

    /**
     * Gets all questionobjects of the evaluation
     * @access   private
     * @param EvaluationObject   &$object An evaluationobject object
     */
    public function getQuestionobjects(&$object)
    {
        if ($object->x_instanceof() == INSTANCEOF_EVALQUESTION) {
            array_push($this->evalquestions, $object);
        } else {
            while ($child = $object->getNextChild()) {
                $this->getQuestionobjects($child);
            }
        }
    }

    /**
     * Closes all opened files
     * @access   public
     */
    public function closeFile()
    {
        if (empty($this->filehandle)) {
            return $this->throwError(1, _("ExportManager::Konnte temporäre Datei nicht schließen."));
        }

        fclose($this->filehandle);
    }

    /**
     * Removes old temporary files
     * @access   private
     */
    public function cleanUp()
    {
        if (empty ($this->filehandle)) {
            return $this->throwError(1, _("ExportManager::Konnte temporäre Datei nicht öffnen."));
        }

        $dirhandle = dir($GLOBALS['TMP_PATH']);
        while (($file = $dirhandle->read()) != false) {
            $file = $GLOBALS['TMP_PATH'] . "/" . $file;
            $part = pathinfo($file);

            if (filemtime($file) < (time() - EVALEXPORT_LIFETIME) &&
                $part["extension"] == $this->extension &&
                mb_substr($part["basename"], 0, mb_strlen(EVALEXPORT_PREFIX)) == EVALEXPORT_PREFIX)
                unlink($file);
        }
        $dirhandle->close();
    }

    /**
     * Creates a new temporary file
     * @access   public
     */
    public function createNewFile()
    {
        $randomID = StudipObject::createNewID();
        $this->filename = $randomID . "." . $this->extension;
        export_tmp_gc();
        if (!is_dir($GLOBALS['TMP_PATH'])) {
            return $this->throwError(1, sprintf(_("ExportManager::Das Verzeichnis %s existiert nicht."), $GLOBALS['TMP_PATH']));
        }
        if (!is_writable($GLOBALS['TMP_PATH'])) {
            return $this->throwError(2, sprintf(_("ExportManager::Das Verzeichnis %s ist nicht schreibbar nicht."), $GLOBALS['TMP_PATH']));
        }

        $this->filehandle = @fopen($GLOBALS['TMP_PATH'] . "/" . $this->filename, "w");

        if (empty ($this->filehandle)) {
            return $this->throwError(3, _("ExportManager::Konnte temporäre Datei nicht erstellen."));
        }
    }

}