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PHP Cross Reference of Moodle 1.9.3 [Build 15-Oct-2008] |
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1 <?php 2 /** 3 * Global Search Engine for Moodle 4 * 5 * @package search 6 * @category core 7 * @subpackage document_wrappers 8 * @author Valery Fremaux [valery.fremaux@club-internet.fr] > 1.8 9 * @date 2008/03/31 10 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License 11 * 12 * document handling for chat activity module 13 * This file contains the mapping between a chat history and it's indexable counterpart, 14 * 15 * Functions for iterating and retrieving the necessary records are now also included 16 * in this file, rather than mod/chat/lib.php 17 * 18 */ 19 20 /** 21 * includes and requires 22 */ 23 require_once("$CFG->dirroot/search/documents/document.php"); 24 require_once("$CFG->dirroot/mod/chat/lib.php"); 25 26 /** 27 * a class for representing searchable information 28 * 29 */ 30 class ChatTrackSearchDocument extends SearchDocument { 31 32 /** 33 * constructor 34 */ 35 public function __construct(&$chatsession, $chat_module_id, $course_id, $group_id, $context_id) { 36 // generic information; required 37 $doc->docid = $chat_module_id.'-'.$chatsession['sessionstart'].'-'.$chatsession['sessionend']; 38 $doc->documenttype = SEARCH_TYPE_CHAT; 39 $doc->itemtype = 'session'; 40 $doc->contextid = $context_id; 41 42 $duration = $chatsession['sessionend'] - $chatsession['sessionstart']; 43 // we cannot call userdate with relevant locale at indexing time. 44 $doc->title = get_string('chatreport', 'chat').' '.get_string('openedon', 'search').' TT_'.$chatsession['sessionstart'].'_TT ('.get_string('duration', 'search').' : '.get_string('numseconds', '', $duration).')'; 45 $doc->date = $chatsession['sessionend']; 46 47 //remove '(ip.ip.ip.ip)' from chat author list 48 $doc->author = preg_replace('/\(.*?\)/', '', $chatsession['authors']); 49 $doc->contents = $chatsession['content']; 50 $doc->url = chat_make_link($chat_module_id, $chatsession['sessionstart'], $chatsession['sessionend']); 51 52 // module specific information; optional 53 $data->chat = $chat_module_id; 54 55 // construct the parent class 56 parent::__construct($doc, $data, $course_id, $group_id, 0, PATH_FOR_SEARCH_TYPE_CHAT); 57 } 58 } 59 60 61 /** 62 * constructs a valid link to a chat content 63 * @param cm_id the chat course module 64 * @param start the start time of the session 65 * @param end th end time of the session 66 * @uses CFG 67 * @return a well formed link to session display 68 */ 69 function chat_make_link($cm_id, $start, $end) { 70 global $CFG; 71 72 return $CFG->wwwroot.'/mod/chat/report.php?id='.$cm_id.'&start='.$start.'&end='.$end; 73 } 74 75 /** 76 * fetches all the records for a given session and assemble them as a unique track 77 * we revamped here the code of report.php for making sessions, but without any output. 78 * note that we should collect sessions "by groups" if groupmode() is SEPARATEGROUPS. 79 * @param int $chat_id the database 80 * @param int $fromtime 81 * @param int $totime 82 * @uses CFG 83 * @return an array of objects representing the chat sessions. 84 */ 85 function chat_get_session_tracks($chat_id, $fromtime = 0, $totime = 0) { 86 global $CFG; 87 88 $chat = get_record('chat', 'id', $chat_id); 89 $course = get_record('course', 'id', $chat->course); 90 $coursemodule = get_field('modules', 'id', 'name', 'data'); 91 $cm = get_record('course_modules', 'course', $course->id, 'module', $coursemodule, 'instance', $chat->id); 92 $groupmode = groupmode($course, $cm); 93 94 $fromtimeclause = ($fromtime) ? "AND timestamp >= {$fromtime}" : ''; 95 $totimeclause = ($totime) ? "AND timestamp <= {$totime}" : ''; 96 $tracks = array(); 97 $messages = get_records_select('chat_messages', "chatid = '{$chat_id}' $fromtimeclause $totimeclause", "timestamp DESC"); 98 if ($messages){ 99 // splits discussions against groups 100 $groupedMessages = array(); 101 if ($groupmode != SEPARATEGROUPS){ 102 foreach($messages as $aMessage){ 103 $groupedMessages[$aMessage->groupid][] = $aMessage; 104 } 105 } else { 106 $groupedMessages[-1] = &$messages; 107 } 108 $sessiongap = 5 * 60; // 5 minutes silence means a new session 109 $sessionend = 0; 110 $sessionstart = 0; 111 $sessionusers = array(); 112 $lasttime = time(); 113 114 foreach ($groupedMessages as $groupId => $messages) { // We are walking BACKWARDS through the messages 115 $messagesleft = count($messages); 116 foreach ($messages as $message) { // We are walking BACKWARDS through the messages 117 $messagesleft --; // Countdown 118 119 if ($message->system) { 120 continue; 121 } 122 // we are within a session track 123 if ((($lasttime - $message->timestamp) < $sessiongap) and $messagesleft) { // Same session 124 if (count($tracks) > 0){ 125 if ($message->userid) { // Remember user and count messages 126 $tracks[count($tracks) - 1]->sessionusers[$message->userid] = $message->userid; 127 // update last track (if exists) record appending content (remember : we go backwards) 128 } 129 $tracks[count($tracks) - 1]->content .= ' '.$message->message; 130 $tracks[count($tracks) - 1]->sessionstart = $message->timestamp; 131 } 132 } else { 133 // we initiate a new session track (backwards) 134 $track = new Object(); 135 $track->sessionend = $message->timestamp; 136 $track->sessionstart = $message->timestamp; 137 $track->content = $message->message; 138 // reset the accumulator of users 139 $track->sessionusers = array(); 140 $track->sessionusers[$message->userid] = $message->userid; 141 $track->groupid = $groupId; 142 $tracks[] = $track; 143 } 144 $lasttime = $message->timestamp; 145 } 146 } 147 } 148 return $tracks; 149 } 150 151 /** 152 * part of search engine API 153 * 154 */ 155 function chat_iterator() { 156 $chatrooms = get_records('chat'); 157 return $chatrooms; 158 } 159 160 /** 161 * part of search engine API 162 * 163 */ 164 function chat_get_content_for_index(&$chat) { 165 $documents = array(); 166 $course = get_record('course', 'id', $chat->course); 167 $coursemodule = get_field('modules', 'id', 'name', 'chat'); 168 $cm = get_record('course_modules', 'course', $chat->course, 'module', $coursemodule, 'instance', $chat->id); 169 if ($cm){ 170 $context = get_context_instance(CONTEXT_MODULE, $cm->id); 171 172 // getting records for indexing 173 $sessionTracks = chat_get_session_tracks($chat->id); 174 if ($sessionTracks){ 175 foreach($sessionTracks as $aTrackId => $aTrack) { 176 foreach($aTrack->sessionusers as $aUserId){ 177 $user = get_record('user', 'id', $aUserId); 178 $aTrack->authors = ($user) ? fullname($user) : '' ; 179 $documents[] = new ChatTrackSearchDocument(get_object_vars($aTrack), $cm->id, $chat->course, $aTrack->groupid, $context->id); 180 } 181 } 182 } 183 return $documents; 184 } 185 return array(); 186 } 187 188 /** 189 * returns a single data search document based on a chat_session id 190 * chat session id is a text composite identifier made of : 191 * - the chat id 192 * - the timestamp when the session starts 193 * - the timestamp when the session ends 194 * @param id the multipart chat session id 195 * @param itemtype the type of information (session is the only type) 196 */ 197 function chat_single_document($id, $itemtype) { 198 list($chat_id, $sessionstart, $sessionend) = split('-', $id); 199 $chat = get_record('chat', 'id', $chat_id); 200 $course = get_record('course', 'id', $chat->course); 201 $coursemodule = get_field('modules', 'id', 'name', 'chat'); 202 $cm = get_record('course_modules', 'course', $course->id, 'module', $coursemodule, 'instance', $chat->id); 203 if ($cm){ 204 $context = get_context_instance(CONTEXT_MODULE, $cm->id); 205 206 // should be only one 207 $tracks = chat_get_session_tracks($chat->id, $sessionstart, $sessionstart); 208 if ($tracks){ 209 $aTrack = $tracks[0]; 210 $document = new ChatTrackSearchDocument(get_object_vars($aTrack), $cm->id, $chat->course, $aTrack->groupid, $context->id); 211 return $document; 212 } 213 } 214 return null; 215 } 216 217 /** 218 * dummy delete function that packs id with itemtype. 219 * this was here for a reason, but I can't remember it at the moment. 220 * 221 */ 222 function chat_delete($info, $itemtype) { 223 $object->id = $info; 224 $object->itemtype = $itemtype; 225 return $object; 226 } 227 228 /** 229 * returns the var names needed to build a sql query for addition/deletions 230 * // TODO chat indexable records are virtual. Should proceed in a special way 231 */ 232 function chat_db_names() { 233 //[primary id], [table name], [time created field name], [time modified field name] 234 return null; 235 } 236 237 /** 238 * this function handles the access policy to contents indexed as searchable documents. If this 239 * function does not exist, the search engine assumes access is allowed. 240 * When this point is reached, we already know that : 241 * - user is legitimate in the surrounding context 242 * - user may be guest and guest access is allowed to the module 243 * - the function may perform local checks within the module information logic 244 * @param path the access path to the module script code 245 * @param itemtype the information subclassing (usefull for complex modules, defaults to 'standard') 246 * @param this_id the item id within the information class denoted by entry_type. In chats, this id 247 * points out a session history which is a close sequence of messages. 248 * @param user the user record denoting the user who searches 249 * @param group_id the current group used by the user when searching 250 * @uses CFG 251 * @return true if access is allowed, false elsewhere 252 */ 253 function chat_check_text_access($path, $itemtype, $this_id, $user, $group_id, $context_id){ 254 global $CFG; 255 256 include_once("{$CFG->dirroot}/{$path}/lib.php"); 257 258 list($chat_id, $sessionstart, $sessionend) = split('-', $id); 259 260 // get the chat session and all related stuff 261 $chat = get_record('chat', 'id', $chat_id); 262 $context = get_record('context', 'id', $context_id); 263 $cm = get_record('course_modules', 'id', $context->instanceid); 264 // $cm = get_coursemodule_from_instance('chat', $chat->id, $chat->course); 265 // $context = get_context_instance(CONTEXT_MODULE, $cm->id); 266 267 if (!$cm->visible and !has_capability('moodle/course:viewhiddenactivities', $context)){ 268 if (!empty($CFG->search_access_debug)) echo "search reject : hidden chat "; 269 return false; 270 } 271 272 //group consistency check : checks the following situations about groups 273 // trap if user is not same group and groups are separated 274 $current_group = get_current_group($course->id); 275 $course = get_record('course', 'id', $chat->course); 276 if ((groupmode($course, $cm) == SEPARATEGROUPS) && !ismember($group_id) && !has_capability('moodle/site:accessallgroups', $context)){ 277 if (!empty($CFG->search_access_debug)) echo "search reject : chat element is in separated group "; 278 return false; 279 } 280 281 //ownership check : checks the following situations about user 282 // trap if user is not owner and has cannot see other's entries 283 // TODO : typically may be stored into indexing cache 284 if (!has_capability('mod/chat:readlog', $context)){ 285 if (!empty($CFG->search_access_debug)) echo "search reject : cannot read past sessions "; 286 return false; 287 } 288 289 return true; 290 } 291 292 /** 293 * this call back is called when displaying the link for some last post processing 294 * 295 */ 296 function chat_link_post_processing($title){ 297 setLocale(LC_TIME, substr(current_language(), 0, 2)); 298 $title = preg_replace('/TT_(.*)_TT/e', "userdate(\\1)", $title); 299 return mb_convert_encoding($title, 'UTF-8', 'auto'); 300 } 301 ?>
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| Generated: Wed Jan 14 11:33:29 2009 | Cross-referenced by PHPXref 0.7 |