mod/chat/backuplib.php

   1 <?php //$Id$
   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
  27         global $CFG;
  28
  29         $status = true;
  30
  31         //Iterate over chat table
  32         $chats = get_records ("chat","course",$preferences->backup_course,"id");
  33         if ($chats) {
  34             foreach ($chats as $chat) {
  35                 if (backup_mod_selected($preferences,'chat',$chat->id)) {
  36                     $status = chat_backup_one_mod($bf,$preferences,$chat);
  37                 }
  38             }
  39         }
  40         return $status;
  41     }
  42
  43     function chat_backup_one_mod($bf,$preferences,$chat) {
  44
  45         global $CFG;
  46
  47         if (is_numeric($chat)) {
  48             $chat = get_record('chat','id',$chat);
  49         }
  50
  51         $status = true;
  52
  53         //Start mod
  54         fwrite ($bf,start_tag("MOD",3,true));
  55         //Print chat data
  56         fwrite ($bf,full_tag("ID",4,false,$chat->id));
  57         fwrite ($bf,full_tag("MODTYPE",4,false,"chat"));
  58         fwrite ($bf,full_tag("NAME",4,false,$chat->name));
  59         fwrite ($bf,full_tag("INTRO",4,false,$chat->intro));
  60         fwrite ($bf,full_tag("KEEPDAYS",4,false,$chat->keepdays));
  61         fwrite ($bf,full_tag("STUDENTLOGS",4,false,$chat->studentlogs));
  62         fwrite ($bf,full_tag("SCHEDULE",4,false,$chat->schedule));
  63         fwrite ($bf,full_tag("CHATTIME",4,false,$chat->chattime));
  64         fwrite ($bf,full_tag("TIMEMODIFIED",4,false,$chat->timemodified));
  65         //if we've selected to backup users info, then execute backup_chat_messages
  66         if (backup_userdata_selected($preferences,'chat',$chat->id)) {
  67             $status = backup_chat_messages($bf,$preferences,$chat->id);
  68         }
  69         //End mod
  70         $status =fwrite ($bf,end_tag("MOD",3,true));
  71
  72         return $status;
  73     }
  74
  75     //Backup chat_messages contents (executed from chat_backup_mods)
  76     function backup_chat_messages ($bf,$preferences,$chat) {
  77
  78         global $CFG;
  79
  80         $status = true;
  81
  82         $chat_messages = get_records("chat_messages","chatid",$chat,"id");
  83         //If there is messages
  84         if ($chat_messages) {
  85             //Write start tag
  86             $status =fwrite ($bf,start_tag("MESSAGES",4,true));
  87             //Iterate over each message
  88             foreach ($chat_messages as $cha_mes) {
  89                 //Start message
  90                 $status =fwrite ($bf,start_tag("MESSAGE",5,true));
  91                 //Print message contents
  92                 fwrite ($bf,full_tag("ID",6,false,$cha_mes->id));
  93                 fwrite ($bf,full_tag("USERID",6,false,$cha_mes->userid));
  94                 fwrite ($bf,full_tag("GROUPID",6,false,$cha_mes->groupid));
  95                 fwrite ($bf,full_tag("SYSTEM",6,false,$cha_mes->system));
  96                 fwrite ($bf,full_tag("MESSAGE_TEXT",6,false,$cha_mes->message));
  97                 fwrite ($bf,full_tag("TIMESTAMP",6,false,$cha_mes->timestamp));
  98                 //End submission
  99                 $status =fwrite ($bf,end_tag("MESSAGE",5,true));
 100             }
 101             //Write end tag
 102             $status =fwrite ($bf,end_tag("MESSAGES",4,true));
 103         }
 104         return $status;
 105     }
 106
 107     //Return an array of info (name,value)
 108     function chat_check_backup_mods($course,$user_data=false,$backup_unique_code,$instances=null) {
 109
 110         if (!empty($instances) && is_array($instances) && count($instances)) {
 111             $info = array();
 112             foreach ($instances as $id => $instance) {
 113                 $info += chat_check_backup_mods_instances($instance,$backup_unique_code);
 114             }
 115             return $info;
 116         }
 117         //First the course data
 118         $info[0][0] = get_string("modulenameplural","chat");
 119         if ($ids = chat_ids ($course)) {
 120             $info[0][1] = count($ids);
 121         } else {
 122             $info[0][1] = 0;
 123         }
 124
 125         //Now, if requested, the user_data
 126         if ($user_data) {
 127             $info[1][0] = get_string("messages","chat");
 128             if ($ids = chat_message_ids_by_course ($course)) {
 129                 $info[1][1] = count($ids);
 130             } else {
 131                 $info[1][1] = 0;
 132             }
 133         }
 134         return $info;
 135     }
 136
 137     //Return an array of info (name,value)
 138     function chat_check_backup_mods_instances($instance,$backup_unique_code) {
 139         //First the course data
 140         $info[$instance->id.'0'][0] = '<b>'.$instance->name.'</b>';
 141         $info[$instance->id.'0'][1] = '';
 142
 143         //Now, if requested, the user_data
 144         if (!empty($instance->userdata)) {
 145             $info[$instance->id.'1'][0] = get_string("messages","chat");
 146             if ($ids = chat_message_ids_by_instance ($instance->id)) {
 147                 $info[$instance->id.'1'][1] = count($ids);
 148             } else {
 149                 $info[$instance->id.'1'][1] = 0;
 150             }
 151         }
 152         return $info;
 153     }
 154
 155     //Return a content encoded to support interactivities linking. Every module
 156     //should have its own. They are called automatically from the backup procedure.
 157     function chat_encode_content_links ($content,$preferences) {
 158
 159         global $CFG;
 160
 161         $base = preg_quote($CFG->wwwroot,"/");
 162
 163         //Link to the list of chats
 164         $buscar="/(".$base."\/mod\/chat\/index.php\?id\=)([0-9]+)/";
 165         $result= preg_replace($buscar,'$@CHATINDEX*$2@$',$content);
 166
 167         //Link to chat view by moduleid
 168         $buscar="/(".$base."\/mod\/chat\/view.php\?id\=)([0-9]+)/";
 169         $result= preg_replace($buscar,'$@CHATVIEWBYID*$2@$',$result);
 170
 171         return $result;
 172     }
 173
 174     // INTERNAL FUNCTIONS. BASED IN THE MOD STRUCTURE
 175
 176     //Returns an array of chats id
 177     function chat_ids ($course) {
 178
 179         global $CFG;
 180
 181         return get_records_sql ("SELECT c.id, c.course
 182                                  FROM {$CFG->prefix}chat c
 183                                  WHERE c.course = '$course'");
 184     }
 185
 186     //Returns an array of assignment_submissions id
 187     function chat_message_ids_by_course ($course) {
 188
 189         global $CFG;
 190
 191         return get_records_sql ("SELECT m.id , m.chatid
 192                                  FROM {$CFG->prefix}chat_messages m,
 193                                       {$CFG->prefix}chat c
 194                                  WHERE c.course = '$course' AND
 195                                        m.chatid = c.id");
 196     }
 197
 198     //Returns an array of chat id
 199     function chat_message_ids_by_instance ($instanceid) {
 200
 201         global $CFG;
 202
 203         return get_records_sql ("SELECT m.id , m.chatid
 204                                  FROM {$CFG->prefix}chat_messages m
 205                                  WHERE m.chatid = $instanceid");
 206     }
 207 ?>