mod/chat/gui_header_js/jsupdated.php

   1 <?php  // $Id$
   2
   3 /** jsupdated.php - notes by Martin Langhoff <martin@catalyst.net.nz>
   4  **
   5  ** This is an alternative version of jsupdate.php that acts
   6  ** as a long-running daemon. It will feed/stall/feed JS updates
   7  ** to the client. From the module configuration select "Stream"
   8  ** updates.
   9  **
  10  ** The client connection is not forever though. Once we reach
  11  ** CHAT_MAX_CLIENT_UPDATES, it will force the client to re-fetch it.
  12  **
  13  ** This buys us all the benefits that chatd has, minus the setup,
  14  ** as we are using apache to do the daemon handling.
  15  **
  16  **/
  17
  18
  19     define('CHAT_MAX_CLIENT_UPDATES', 1000);
  20     $nomoodlecookie = true;     // Session not needed!
  21
  22     require('../../../config.php');
  23     require('../lib.php');
  24
  25     // we are going to run for a long time
  26     // avoid being terminated by php
  27     @set_time_limit(0);
  28
  29     $chat_sid      = required_param('chat_sid',          PARAM_ALPHANUM);
  30     $chat_lasttime = optional_param('chat_lasttime',  0, PARAM_INT);
  31     $chat_lastrow  = optional_param('chat_lastrow',   1, PARAM_INT);
  32     $chat_lastid   = optional_param('chat_lastid',    0, PARAM_INT);
  33
  34     if (!$chatuser = get_record('chat_users', 'sid', $chat_sid)) {
  35         error('Not logged in!');
  36     }
  37
  38     //Get the minimal course
  39     if (!$course = get_record('course','id',$chatuser->course,'','','','','id,theme,lang')) {
  40         error('incorrect course id');
  41     }
  42
  43     //Get the user theme and enough info to be used in chat_format_message() which passes it along to
  44     // chat_format_message_manually() -- and only id and timezone are used.
  45     if (!$USER = get_record('user','id',$chatuser->userid,'','','','','id, lang, theme, username, timezone')) {
  46         error('User does not exist!');
  47     }
  48     $USER->description = '';
  49
  50     //Setup course, lang and theme
  51     course_setup($course);
  52
  53     // force deleting of timed out users if there is a silence in room or just entering
  54     if ((time() - $chat_lasttime) > $CFG->chat_old_ping) {
  55         // must be done before chat_get_latest_message!!!
  56         chat_delete_old_users();
  57     }
  58
  59     //
  60     // Time to send headers, and lay out the basic JS updater page
  61     //
  62     header('Expires: Sun, 28 Dec 1997 09:32:45 GMT');
  63     header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
  64     header('Cache-Control: no-cache, must-revalidate');
  65     header('Pragma: no-cache');
  66     header('Content-Type: text/html; charset=utf-8');
  67
  68     /// required stylesheets
  69     $stylesheetshtml = '';
  70     foreach ($CFG->stylesheets as $stylesheet) {
  71         $stylesheetshtml .= '<link rel="stylesheet" type="text/css" href="'.$stylesheet.'" />';
  72     }
  73
  74 ?>
  75 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
  76 <html>
  77     <head>
  78         <meta http-equiv="content-type" content="text/html; charset=utf-8" />
  79         <script type="text/javascript">
  80         //<![CDATA[
  81         if (parent.msg.document.getElementById("msgStarted") == null) {
  82             parent.msg.document.close();
  83             parent.msg.document.open("text/html","replace");
  84             parent.msg.document.write("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">");
  85             parent.msg.document.write("<html><head>");
  86             parent.msg.document.write("<meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\" />");
  87             parent.msg.document.write("<base target=\"_blank\" />");
  88             parent.msg.document.write("<?php echo addslashes_js($stylesheetshtml) ?>");
  89             parent.msg.document.write("</head><body class=\"mod-chat-gui_header_js course-<?php echo $chatuser->course ?>\" id=\"mod-chat-gui_header_js-jsupdate\"><div style=\"display: none\" id=\"msgStarted\">&nbsp;</div>");
  90         }
  91         //]]>
  92         </script>
  93    </head>
  94    <body>
  95
  96 <?php
  97
  98     // Ensure the HTML head makes it out there
  99     echo $CHAT_DUMMY_DATA;
 100     @ob_end_flush();
 101
 102     for ($n=0; $n <= CHAT_MAX_CLIENT_UPDATES; $n++) {
 103
 104         // ping first so we can later shortcut as needed.
 105         $chatuser->lastping = time();
 106         set_field('chat_users', 'lastping', $chatuser->lastping, 'id', $chatuser->id  );
 107
 108         if ($message = chat_get_latest_message($chatuser->chatid, $chatuser->groupid)) {
 109             $chat_newlasttime = $message->timestamp;
 110             $chat_newlastid   = $message->id;
 111         } else {
 112             $chat_newlasttime = 0;
 113             $chat_newlastid   = 0;
 114             print " \n";
 115             print $CHAT_DUMMY_DATA;
 116             @ob_end_flush();
 117             sleep($CFG->chat_refresh_room);
 118             continue;
 119         }
 120
 121         $timenow    = time();
 122
 123
 124         $groupselect = $chatuser->groupid ? " AND (groupid='".$chatuser->groupid."' OR groupid='0') " : "";
 125
 126         $newcriteria = '';
 127         if ($chat_lastid > 0) {
 128             $newcriteria = "id > $chat_lastid";
 129         } else {
 130             if ($chat_lasttime == 0) { //display some previous messages
 131                 $chat_lasttime = $timenow - $CFG->chat_old_ping; //TO DO - any better value??
 132             }
 133             $newcriteria = "timestamp > $chat_lasttime";
 134         }
 135
 136         $messages = get_records_select("chat_messages",
 137                                        "chatid = '$chatuser->chatid' AND $newcriteria $groupselect",
 138                                        "timestamp ASC");
 139
 140         if ($messages) {
 141             $num = count($messages);
 142         } else {
 143             print " \n";
 144             print $CHAT_DUMMY_DATA;
 145             @ob_end_flush();
 146             sleep($CFG->chat_refresh_room);
 147             continue;
 148             $num = 0;
 149         }
 150
 151         print '<script type="text/javascript">' . "\n";
 152         print "//<![CDATA[\n\n";
 153
 154         $chat_newrow = ($chat_lastrow + $num) % 2;
 155
 156         $refreshusers = false;
 157         $us = array ();
 158         if (($chat_lasttime != $chat_newlasttime) and $messages) {
 159
 160             $beep         = false;
 161             $refreshusers = false;
 162             foreach ($messages as $message) {
 163                 $chat_lastrow = ($chat_lastrow + 1) % 2;
 164                 $formatmessage = chat_format_message($message, $chatuser->course, $USER, $chat_lastrow);
 165                 if ($formatmessage->beep) {
 166                     $beep = true;
 167                 }
 168                 if ($formatmessage->refreshusers) {
 169                     $refreshusers = true;
 170                 }
 171                 $us[$message->userid] = $timenow - $message->timestamp;
 172                 echo "parent.msg.document.write('".addslashes_js($formatmessage->html )."\\n');\n";
 173
 174             }
 175             // from the last message printed...
 176             // a strange case where lack of closures is useful!
 177             $chat_lasttime = $message->timestamp;
 178             $chat_lastid   = $message->id;
 179         }
 180
 181         if ($refreshusers) {
 182             echo "if (parent.users.document.anchors[0] != null) {" .
 183                 "parent.users.location.href = parent.users.document.anchors[0].href;}\n";
 184         } else {
 185             foreach($us as $uid=>$lastping) {
 186                 $min = (int) ($lastping/60);
 187                 $sec = $lastping - ($min*60);
 188                 $min = $min < 10 ? '0'.$min : $min;
 189                 $sec = $sec < 10 ? '0'.$sec : $sec;
 190                 $idle = $min.':'.$sec;
 191                 echo "if (parent.users.document.getElementById('uidle{$uid}') != null) {".
 192                         "parent.users.document.getElementById('uidle{$uid}').innerHTML = '$idle';}\n";
 193             }
 194         }
 195
 196         print 'parent.msg.scroll(1,5000000);' . "\n\n";
 197         print "//]]>\n";
 198         print '</script>' . "\n\n";
 199         if ($beep) {
 200             print '<embed src="../beep.wav" autostart="true" hidden="true" name="beep" />';
 201         }
 202         print $CHAT_DUMMY_DATA;
 203         @ob_end_flush();
 204         sleep($CFG->chat_refresh_room);
 205     } // here ends the for() loop
 206
 207     // here & should be written & :-D
 208     $refreshurl = "{$CFG->wwwroot}/mod/chat/gui_header_js/jsupdated.php?chat_sid=$chat_sid&chat_lasttime=$chat_lasttime&chat_lastrow=$chat_newrow&chat_lastid=$chat_lastid";
 209     print '<script type="text/javascript">' . "\n";
 210     print "//<![CDATA[ \n\n";
 211     print "location.href = '$refreshurl';\n";
 212     print "//]]>\n";
 213     print '</script>' . "\n\n";
 214
 215 ?>
 216
 217     </body>
 218 </html>