Modules/Exercise/classes/class.ilExerciseXMLParser.php

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<?php
/*
        +-----------------------------------------------------------------------------+
        | ILIAS open source                                                           |
        +-----------------------------------------------------------------------------+
        | Copyright (c) 1998-2001 ILIAS open source, University of Cologne            |
        |                                                                             |
        | 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 (at your option) 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_once 'classes/class.ilSaxParser.php';
include_once 'Modules/Exercise/classes/class.ilExerciseException.php';



class ilExerciseXMLParser extends ilSaxParser
{

    static $CONTENT_NOT_COMPRESSED = 0;
    static $CONTENT_GZ_COMPRESSED = 1;
    static $CONTENT_ZLIB_COMPRESSED = 2;

    var $exercise;

    var $obj_id;


    var $result;

    var $mode;

        function ilExerciseXMLParser(& $exercise, $a_xml_data, $obj_id = -1)
        {
                parent::ilSaxParser();
                $this->exercise = $exercise;
                $this->setXMLContent($a_xml_data);
                $this->obj_id = $obj_id;
                $this->result = false;
        }


        function setHandlers($a_xml_parser)
        {
                xml_set_object($a_xml_parser,$this);
                xml_set_element_handler($a_xml_parser,'handlerBeginTag','handlerEndTag');
                xml_set_character_data_handler($a_xml_parser,'handlerCharacterData');
        }

        function handlerBeginTag($a_xml_parser,$a_name,$a_attribs)
        {
                global $ilErr;

                switch($a_name)
                {
                        case 'Exercise':
                            if (isset($a_attribs["obj_id"]))
                            {
                   $read_obj_id = ilUtil::__extractId($a_attribs["obj_id"], IL_INST_ID);
                               if ($this->obj_id != -1 && (int) $read_obj_id  != -1 && (int) $this->obj_id != (int) $read_obj_id)
                               {
                       throw new ilExerciseException ("Object IDs (xml $read_obj_id and argument ".$this->obj_id.") do not match!", ilExerciseException::$ID_MISMATCH);
                   }
                            }
                                break;
                        case 'Member':
                            $this->usr_action = $a_attribs["action"];
                            $this->usr_id = ilUtil::__extractId($a_attribs["usr_id"], IL_INST_ID);
                                break;

                        case 'File':
                $this->file_action = $a_attribs["action"];
                                break;
                        case 'Content':
                $this->mode = ilExerciseXMLParser::$CONTENT_NOT_COMPRESSED;
                            if ($a_attribs["mode"] == "GZIP")
                            {
                    if (!function_exists("gzdecode"))
                        throw new  ilExerciseException ("Deflating with gzip is not supported",  ilExerciseException::$ID_DEFLATE_METHOD_MISMATCH);

                                $this->mode = ilExerciseXMLParser::$CONTENT_GZ_COMPRESSED;
                            } elseif ($a_attribs["mode"] == "ZLIB")
                            {
                    if (!function_exists("gzuncompress"))
                        throw new ilExerciseException ("Deflating with zlib (compress/uncompress) is not supported",  ilExerciseException::$ID_DEFLATE_METHOD_MISMATCH);

                                $this->mode = ilExerciseXMLParser::$CONTENT_ZLIB_COMPRESSED;
                            }
                            break;

                }
        }



        function handlerEndTag($a_xml_parser,$a_name)
        {
                switch($a_name)
                {
                        case 'Exercise':
                  $this->result = true;
                                break;
                        case 'Title':
                            $this->exercise->setTitle(trim($this->cdata));
                                break;
                        case 'Description':
                            $this->exercise->setDescription(trim($this->cdata));
                                break;
                        case 'Instruction':
                                $this->exercise->setInstruction(trim($this->cdata));
                                break;
                        case 'DueDate':
                                $this->exercise->setTimestamp(trim($this->cdata));
                                break;
                        case 'Member':
                            $this->updateMember($this->usr_id, $this->usr_action);
                            break;
                        case 'Filename':
                            $this->file_name = trim($this->cdata);
                            break;
                        case 'Content':
                            $this->file_content = trim($this->cdata);
                            break;
                        case 'File':
                $this->updateFile($this->file_name, $this->file_content, $this->file_action);
                            break;

                }

                $this->cdata = '';

                return;
        }

        function handlerCharacterData($a_xml_parser,$a_data)
        {
                if($a_data != "\n")
                {
                        $this->cdata .= $a_data;
                }
        }


        private function updateMember ($user_id, $action) {
       if (!is_int($user_id) || $user_id <= 0) {
           return;
       }
           $memberObject = $this->exercise->members_obj;

           if ($action == "Attach" && !$memberObject->isAssigned($user_id))
           {
            $memberObject->assignMember ($user_id);
       }

       if ($action == "Detach" && $memberObject->isAssigned($user_id))
       {
            $memberObject->deassignMember ($user_id);
       }
        }

        private function updateFile ($filename, $b64encodedContent, $action)
        {
       if (strlen($filename) == 0) {
           return;
       }

            $fileObject = $this->exercise->file_obj;
        if ($action == "Attach")
        {
           $content = base64_decode((string) $b64encodedContent);
           if ($this->mode == ilExerciseXMLParser::$CONTENT_GZ_COMPRESSED) {
                $content = gzdecode($content);
               }elseif ($this->mode ==ilExerciseXMLParser::$CONTENT_ZLIB_COMPRESSED) {
                $content = gzuncompress($content);
               }
           $fileObject->storeContentAsFile ($filename, $content);
        }
        if ($action == "Detach")
        {
            $fileObject->unlinkFile ($filename);
        }
        }

        public function start () {
            $this->startParsing();
            return $this->result > 0;
        }

}
?>