mod/chat/backuplib.php

   1 <?php
   2     //This php script contains all the stuff to backup/restore
   3     //chat mods
   4
   5     //This is the "graphical" structure of the chat mod:
   6     //
   7     //                       chat
   8     //                    (CL,pk->id)
   9     //                        |
  10     //                        |
  11     //                        |
  12     //                   chat_messages
  13     //               (UL,pk->id, fk->chatid)
  14     //
  15     // Meaning: pk->primary key field of the table
  16     //          fk->foreign key to link with parent
  17     //          nt->nested field (recursive data)
  18     //          CL->course level info
  19     //          UL->user level info
  20     //          files->table may have files)
  21     //
  22     //-----------------------------------------------------------
  23
  24     //This function executes all the backup procedure about this mod
  25     function chat_backup_mods($bf,$preferences) {
  26         global $CFG, $DB;
  27
  28         $status = true;
  29
  30         //Iterate over chat table
  31         $chats = $DB->get_records ("chat", array("course"=>$preferences->backup_course), "id");
  32         if ($chats) {
  33             foreach ($chats as $chat) {
  34                 if (backup_mod_selected($preferences,'chat',$chat->id)) {
  35                     $status = chat_backup_one_mod($bf,$preferences,$chat);
  36                 }
  37             }
  38         }
  39         return $status;
  40     }
  41
  42     function chat_backup_one_mod($bf,$preferences,$chat) {
  43         global $CFG, $DB;
  44
  45         if (is_numeric($chat)) {
  46             $chat = $DB->get_record('chat', array('id'=>$chat));
  47         }
  48
  49         $status = true;
  50
  51         //Start mod
  52         fwrite ($bf,start_tag("MOD",3,true));
  53         //Print chat data
  54         fwrite ($bf,full_tag("ID",4,false,$chat->id));
  55         fwrite ($bf,full_tag("MODTYPE",4,false,"chat"));
  56         fwrite ($bf,full_tag("NAME",4,false,$chat->name));
  57         fwrite ($bf,full_tag("INTRO",4,false,$chat->intro));
  58         fwrite ($bf,full_tag("KEEPDAYS",4,false,$chat->keepdays));
  59         fwrite ($bf,full_tag("STUDENTLOGS",4,false,$chat->studentlogs));
  60         fwrite ($bf,full_tag("SCHEDULE",4,false,$chat->schedule));
  61         fwrite ($bf,full_tag("CHATTIME",4,false,$chat->chattime));
  62         fwrite ($bf,full_tag("TIMEMODIFIED",4,false,$chat->timemodified));
  63         //if we've selected to backup users info, then execute backup_chat_messages
  64         if (backup_userdata_selected($preferences,'chat',$chat->id)) {
  65             $status = backup_chat_messages($bf,$preferences,$chat->id);
  66         }
  67         //End mod
  68         $status =fwrite ($bf,end_tag("MOD",3,true));
  69
  70         return $status;
  71     }
  72
  73     //Backup chat_messages contents (executed from chat_backup_mods)
  74     function backup_chat_messages ($bf,$preferences,$chat) {
  75         global $CFG, $DB;
  76
  77         $status = true;
  78
  79         $chat_messages = $DB->get_records("chat_messages", array("chatid"=>$chat), "id");
  80         //If there is messages
  81         if ($chat_messages) {
  82             //Write start tag
  83             $status =fwrite ($bf,start_tag("MESSAGES",4,true));
  84             //Iterate over each message
  85             foreach ($chat_messages as $cha_mes) {
  86                 //Start message
  87                 $status =fwrite ($bf,start_tag("MESSAGE",5,true));
  88                 //Print message contents
  89                 fwrite ($bf,full_tag("ID",6,false,$cha_mes->id));
  90                 fwrite ($bf,full_tag("USERID",6,false,$cha_mes->userid));
  91                 fwrite ($bf,full_tag("GROUPID",6,false,$cha_mes->groupid));
  92                 fwrite ($bf,full_tag("SYSTEM",6,false,$cha_mes->system));
  93                 fwrite ($bf,full_tag("MESSAGE_TEXT",6,false,$cha_mes->message));
  94                 fwrite ($bf,full_tag("TIMESTAMP",6,false,$cha_mes->timestamp));
  95                 //End submission
  96                 $status =fwrite ($bf,end_tag("MESSAGE",5,true));
  97             }
  98             //Write end tag
  99             $status =fwrite ($bf,end_tag("MESSAGES",4,true));
 100         }
 101         return $status;
 102     }
 103
 104     //Return an array of info (name,value)
 105     function chat_check_backup_mods($course,$user_data=false,$backup_unique_code,$instances=null) {
 106
 107         if (!empty($instances) && is_array($instances) && count($instances)) {
 108             $info = array();
 109             foreach ($instances as $id => $instance) {
 110                 $info += chat_check_backup_mods_instances($instance,$backup_unique_code);
 111             }
 112             return $info;
 113         }
 114         //First the course data
 115         $info[0][0] = get_string("modulenameplural","chat");
 116         if ($ids = chat_ids ($course)) {
 117             $info[0][1] = count($ids);
 118         } else {
 119             $info[0][1] = 0;
 120         }
 121
 122         //Now, if requested, the user_data
 123         if ($user_data) {
 124             $info[1][0] = get_string("messages","chat");
 125             if ($ids = chat_message_ids_by_course ($course)) {
 126                 $info[1][1] = count($ids);
 127             } else {
 128                 $info[1][1] = 0;
 129             }
 130         }
 131         return $info;
 132     }
 133
 134     //Return an array of info (name,value)
 135     function chat_check_backup_mods_instances($instance,$backup_unique_code) {
 136         //First the course data
 137         $info[$instance->id.'0'][0] = '<b>'.$instance->name.'</b>';
 138         $info[$instance->id.'0'][1] = '';
 139
 140         //Now, if requested, the user_data
 141         if (!empty($instance->userdata)) {
 142             $info[$instance->id.'1'][0] = get_string("messages","chat");
 143             if ($ids = chat_message_ids_by_instance ($instance->id)) {
 144                 $info[$instance->id.'1'][1] = count($ids);
 145             } else {
 146                 $info[$instance->id.'1'][1] = 0;
 147             }
 148         }
 149         return $info;
 150     }
 151
 152     //Return a content encoded to support interactivities linking. Every module
 153     //should have its own. They are called automatically from the backup procedure.
 154     function chat_encode_content_links ($content,$preferences) {
 155
 156         global $CFG;
 157
 158         $base = preg_quote($CFG->wwwroot,"/");
 159
 160         //Link to the list of chats
 161         $buscar="/(".$base."\/mod\/chat\/index.php\?id\=)([0-9]+)/";
 162         $result= preg_replace($buscar,'$@CHATINDEX*$2@$',$content);
 163
 164         //Link to chat view by moduleid
 165         $buscar="/(".$base."\/mod\/chat\/view.php\?id\=)([0-9]+)/";
 166         $result= preg_replace($buscar,'$@CHATVIEWBYID*$2@$',$result);
 167
 168         return $result;
 169     }
 170
 171     // INTERNAL FUNCTIONS. BASED IN THE MOD STRUCTURE
 172
 173     //Returns an array of chats id
 174     function chat_ids ($course) {
 175         global $DB;
 176
 177         return $DB->get_records_sql("SELECT c.id, c.course
 178                                        FROM {chat} c
 179                                       WHERE c.course = ?", array($course));
 180     }
 181
 182     //Returns an array of assignment_submissions id
 183     function chat_message_ids_by_course ($course) {
 184         global $DB;
 185
 186         return $DB->get_records_sql("SELECT m.id , m.chatid
 187                                        FROM {chat_messages} m, {chat} c
 188                                       WHERE c.course = ? AND
 189                                             m.chatid = c.id", array($course));
 190     }
 191
 192     //Returns an array of chat id
 193     function chat_message_ids_by_instance ($instanceid) {
 194         global $DB;
 195
 196         return $DB->get_records_sql("SELECT m.id , m.chatid
 197                                        FROM {chat_messages} m
 198                                       WHERE m.chatid = ?", array($instanceid));
 199     }
 200