lib/plagiarismlib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * plagiarismlib.php - Contains core Plagiarism related functions.
  20  *
  21  * @since Moodle 2.0
  22  * @package    moodlecore
  23  * @subpackage plagiarism
  24  * @copyright  2010 Dan Marsden http://danmarsden.com
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 ///// GENERIC PLAGIARISM FUNCTIONS ////////////////////////////////////////////////////
  29
  30 if (!defined('MOODLE_INTERNAL')) {
  31     die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
  32 }
  33
  34 /**
  35  * displays the similarity score and provides a link to the full report if allowed.
  36  *
  37  * @param object  $linkarray contains all relevant information for the plugin to generate a link
  38  * @return string - url to allow login/viewing of a similarity report
  39  */
  40 function plagiarism_get_links($linkarray) {
  41     global $CFG;
  42     if (empty($CFG->enableplagiarism)) {
  43         return '';
  44     }
  45     $plagiarismplugins = plagiarism_load_available_plugins();
  46     $output = '';
  47     foreach($plagiarismplugins as $plugin => $dir) {
  48         require_once($dir.'/lib.php');
  49         $plagiarismclass = "plagiarism_plugin_$plugin";
  50         $plagiarismplugin = new $plagiarismclass;
  51         $output .= $plagiarismplugin->get_links($linkarray);
  52     }
  53     return $output;
  54 }
  55
  56 /**
  57  * returns array of plagiarism details about specified file
  58  *
  59  * @param int $cmid
  60  * @param int $userid
  61  * @param object $file moodle file object
  62  * @return array - sets of details about specified file, one array of details per plagiarism plugin
  63  *  - each set contains at least 'analyzed', 'score', 'reporturl'
  64  */
  65 function plagiarism_get_file_results($cmid, $userid, $file) {
  66     global $CFG;
  67     $allresults = array();
  68     if (empty($CFG->enableplagiarism)) {
  69         return $allresults;
  70     }
  71     $plagiarismplugins = plagiarism_load_available_plugins();
  72     foreach($plagiarismplugins as $plugin => $dir) {
  73         require_once($dir.'/lib.php');
  74         $plagiarismclass = "plagiarism_plugin_$plugin";
  75         $plagiarismplugin = new $plagiarismclass;
  76         $allresults[] = $plagiarismplugin->get_file_results($cmid, $userid, $file);
  77     }
  78     return $allresults;
  79 }
  80
  81 /**
  82  * saves/updates plagiarism settings from a modules config page - called by course/modedit.php
  83  *
  84  * @param object $data - form data
  85  */
  86 function plagiarism_save_form_elements($data) {
  87     global $CFG;
  88     if (empty($CFG->enableplagiarism)) {
  89         return '';
  90     }
  91     $plagiarismplugins = plagiarism_load_available_plugins();
  92     foreach($plagiarismplugins as $plugin => $dir) {
  93         require_once($dir.'/lib.php');
  94         $plagiarismclass = "plagiarism_plugin_$plugin";
  95         $plagiarismplugin = new $plagiarismclass;
  96         $plagiarismplugin->save_form_elements($data);
  97     }
  98 }
  99
 100 /**
 101  * adds the list of plagiarism settings to a form - called inside modules that have enabled plagiarism
 102  *
 103  * @param object $mform - Moodle form object
 104  * @param object $context - context object
 105  * @param string $modulename - Name of the module
 106  */
 107 function plagiarism_get_form_elements_module($mform, $context, $modulename = "") {
 108     global $CFG;
 109     if (empty($CFG->enableplagiarism)) {
 110         return '';
 111     }
 112     $plagiarismplugins = plagiarism_load_available_plugins();
 113     foreach($plagiarismplugins as $plugin => $dir) {
 114         require_once($dir.'/lib.php');
 115         $plagiarismclass = "plagiarism_plugin_$plugin";
 116         $plagiarismplugin = new $plagiarismclass;
 117         $plagiarismplugin->get_form_elements_module($mform, $context, $modulename);
 118     }
 119 }
 120 /**
 121  * updates the status of all files within a module
 122  *
 123  * @param object $course - full Course object
 124  * @param object $cm - full cm object
 125  * @return string
 126  */
 127 function plagiarism_update_status($course, $cm) {
 128     global $CFG;
 129     if (empty($CFG->enableplagiarism)) {
 130         return '';
 131     }
 132     $plagiarismplugins = plagiarism_load_available_plugins();
 133     $output = '';
 134     foreach($plagiarismplugins as $plugin => $dir) {
 135         require_once($dir.'/lib.php');
 136         $plagiarismclass = "plagiarism_plugin_$plugin";
 137         $plagiarismplugin = new $plagiarismclass;
 138         $output .= $plagiarismplugin->update_status($course, $cm);
 139     }
 140     return $output;
 141 }
 142
 143 /**
 144 * Function that prints the student disclosure notifying that the files will be checked for plagiarism
 145 * @param integer $cmid - the cmid of this module
 146 * @return string
 147 */
 148 function plagiarism_print_disclosure($cmid) {
 149     global $CFG;
 150     if (empty($CFG->enableplagiarism)) {
 151         return '';
 152     }
 153     $plagiarismplugins = plagiarism_load_available_plugins();
 154     $output = '';
 155     foreach($plagiarismplugins as $plugin => $dir) {
 156         require_once($dir.'/lib.php');
 157         $plagiarismclass = "plagiarism_plugin_$plugin";
 158         $plagiarismplugin = new $plagiarismclass;
 159         $output .= $plagiarismplugin->print_disclosure($cmid);
 160     }
 161     return $output;
 162 }
 163 /**
 164  * used by admin/cron.php to get similarity scores from submitted files.
 165  *
 166  */
 167 function plagiarism_cron() {
 168     global $CFG;
 169     if (empty($CFG->enableplagiarism)) {
 170         return '';
 171     }
 172     $plagiarismplugins = plagiarism_load_available_plugins();
 173     foreach($plagiarismplugins as $plugin => $dir) {
 174         require_once($dir.'/lib.php');
 175         $plagiarismclass = "plagiarism_plugin_$plugin";
 176         $plagiarismplugin = new $plagiarismclass;
 177         if (method_exists($plagiarismplugin, 'cron')) {
 178             mtrace('Processing cron function for plagiarism_plugin_' . $plugin . '...', '');
 179             cron_trace_time_and_memory();
 180             $plagiarismplugin->cron();
 181         }
 182     }
 183 }
 184 /**
 185  * helper function - also loads lib file of plagiarism plugin
 186  * @return array of available plugins
 187  */
 188 function plagiarism_load_available_plugins() {
 189     global $CFG;
 190     if (empty($CFG->enableplagiarism)) {
 191         return array();
 192     }
 193     $plagiarismplugins = core_component::get_plugin_list('plagiarism');
 194     $availableplugins = array();
 195     foreach($plagiarismplugins as $plugin => $dir) {
 196         //check this plugin is enabled and a lib file exists.
 197         if (get_config('plagiarism', $plugin."_use") && file_exists($dir."/lib.php")) {
 198             require_once($dir.'/lib.php');
 199             $plagiarismclass = "plagiarism_plugin_$plugin";
 200             if (class_exists($plagiarismclass)) {
 201                 $availableplugins[$plugin] = $dir;
 202             }
 203         }
 204     }
 205     return $availableplugins;
 206 }