message/lib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Library functions for messaging
  19  *
  20  * @package   core_message
  21  * @copyright 2008 Luis Rodrigues
  22  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 require_once($CFG->libdir.'/eventslib.php');
  26
  27 define ('MESSAGE_SHORTLENGTH', 300);
  28
  29 define ('MESSAGE_DISCUSSION_WIDTH',600);
  30 define ('MESSAGE_DISCUSSION_HEIGHT',500);
  31
  32 define ('MESSAGE_SHORTVIEW_LIMIT', 8);//the maximum number of messages to show on the short message history
  33
  34 define('MESSAGE_HISTORY_SHORT',0);
  35 define('MESSAGE_HISTORY_ALL',1);
  36
  37 define('MESSAGE_VIEW_UNREAD_MESSAGES','unread');
  38 define('MESSAGE_VIEW_RECENT_CONVERSATIONS','recentconversations');
  39 define('MESSAGE_VIEW_RECENT_NOTIFICATIONS','recentnotifications');
  40 define('MESSAGE_VIEW_CONTACTS','contacts');
  41 define('MESSAGE_VIEW_BLOCKED','blockedusers');
  42 define('MESSAGE_VIEW_COURSE','course_');
  43 define('MESSAGE_VIEW_SEARCH','search');
  44
  45 define('MESSAGE_SEARCH_MAX_RESULTS', 200);
  46
  47 define('MESSAGE_CONTACTS_PER_PAGE',10);
  48 define('MESSAGE_MAX_COURSE_NAME_LENGTH', 30);
  49
  50 /**
  51  * Define contants for messaging default settings population. For unambiguity of
  52  * plugin developer intentions we use 4-bit value (LSB numbering):
  53  * bit 0 - whether to send message when user is loggedin (MESSAGE_DEFAULT_LOGGEDIN)
  54  * bit 1 - whether to send message when user is loggedoff (MESSAGE_DEFAULT_LOGGEDOFF)
  55  * bit 2..3 - messaging permission (MESSAGE_DISALLOWED|MESSAGE_PERMITTED|MESSAGE_FORCED)
  56  *
  57  * MESSAGE_PERMITTED_MASK contains the mask we use to distinguish permission setting
  58  */
  59
  60 define('MESSAGE_DEFAULT_LOGGEDIN', 0x01); // 0001
  61 define('MESSAGE_DEFAULT_LOGGEDOFF', 0x02); // 0010
  62
  63 define('MESSAGE_DISALLOWED', 0x04); // 0100
  64 define('MESSAGE_PERMITTED', 0x08); // 1000
  65 define('MESSAGE_FORCED', 0x0c); // 1100
  66
  67 define('MESSAGE_PERMITTED_MASK', 0x0c); // 1100
  68
  69 /**
  70  * Set default value for default outputs permitted setting
  71  */
  72 define('MESSAGE_DEFAULT_PERMITTED', 'permitted');
  73
  74 /**
  75  * Print the selector that allows the user to view their contacts, course participants, their recent
  76  * conversations etc
  77  *
  78  * @param int $countunreadtotal how many unread messages does the user have?
  79  * @param int $viewing What is the user viewing? ie MESSAGE_VIEW_UNREAD_MESSAGES, MESSAGE_VIEW_SEARCH etc
  80  * @param object $user1 the user whose messages are being viewed
  81  * @param object $user2 the user $user1 is talking to
  82  * @param array $blockedusers an array of users blocked by $user1
  83  * @param array $onlinecontacts an array of $user1's online contacts
  84  * @param array $offlinecontacts an array of $user1's offline contacts
  85  * @param array $strangers an array of users who have messaged $user1 who aren't contacts
  86  * @param bool $showactionlinks show action links (add/remove contact etc)
  87  * @param int $page if there are so many users listed that they have to be split into pages what page are we viewing
  88  * @return void
  89  */
  90 function message_print_contact_selector($countunreadtotal, $viewing, $user1, $user2, $blockedusers, $onlinecontacts, $offlinecontacts, $strangers, $showactionlinks, $page=0) {
  91     global $PAGE;
  92
  93     echo html_writer::start_tag('div', array('class' => 'contactselector mdl-align'));
  94
  95     //if 0 unread messages and they've requested unread messages then show contacts
  96     if ($countunreadtotal == 0 && $viewing == MESSAGE_VIEW_UNREAD_MESSAGES) {
  97         $viewing = MESSAGE_VIEW_CONTACTS;
  98     }
  99
 100     //if they have no blocked users and they've requested blocked users switch them over to contacts
 101     if (count($blockedusers) == 0 && $viewing == MESSAGE_VIEW_BLOCKED) {
 102         $viewing = MESSAGE_VIEW_CONTACTS;
 103     }
 104
 105     $onlyactivecourses = true;
 106     $courses = enrol_get_users_courses($user1->id, $onlyactivecourses);
 107     $coursecontexts = message_get_course_contexts($courses);//we need one of these again so holding on to them
 108
 109     $strunreadmessages = null;
 110     if ($countunreadtotal>0) { //if there are unread messages
 111         $strunreadmessages = get_string('unreadmessages','message', $countunreadtotal);
 112     }
 113
 114     message_print_usergroup_selector($viewing, $courses, $coursecontexts, $countunreadtotal, count($blockedusers), $strunreadmessages, $user1);
 115
 116     if ($viewing == MESSAGE_VIEW_UNREAD_MESSAGES) {
 117         message_print_contacts($onlinecontacts, $offlinecontacts, $strangers, $PAGE->url, 1, $showactionlinks,$strunreadmessages, $user2);
 118     } else if ($viewing == MESSAGE_VIEW_CONTACTS || $viewing == MESSAGE_VIEW_SEARCH || $viewing == MESSAGE_VIEW_RECENT_CONVERSATIONS || $viewing == MESSAGE_VIEW_RECENT_NOTIFICATIONS) {
 119         message_print_contacts($onlinecontacts, $offlinecontacts, $strangers, $PAGE->url, 0, $showactionlinks, $strunreadmessages, $user2);
 120     } else if ($viewing == MESSAGE_VIEW_BLOCKED) {
 121         message_print_blocked_users($blockedusers, $PAGE->url, $showactionlinks, null, $user2);
 122     } else if (substr($viewing, 0, 7) == MESSAGE_VIEW_COURSE) {
 123         $courseidtoshow = intval(substr($viewing, 7));
 124
 125         if (!empty($courseidtoshow)
 126             && array_key_exists($courseidtoshow, $coursecontexts)
 127             && has_capability('moodle/course:viewparticipants', $coursecontexts[$courseidtoshow])) {
 128
 129             message_print_participants($coursecontexts[$courseidtoshow], $courseidtoshow, $PAGE->url, $showactionlinks, null, $page, $user2);
 130         }
 131     }
 132
 133     // Only show the search button if we're viewing our own messages.
 134     // Search isn't currently able to deal with user A wanting to search user B's messages.
 135     if ($showactionlinks) {
 136         echo html_writer::start_tag('form', array('action' => 'index.php','method' => 'GET'));
 137         echo html_writer::start_tag('fieldset');
 138         $managebuttonclass = 'visible';
 139         if ($viewing == MESSAGE_VIEW_SEARCH) {
 140             $managebuttonclass = 'hiddenelement';
 141         }
 142         $strmanagecontacts = get_string('search','message');
 143         echo html_writer::empty_tag('input', array('type' => 'hidden','name' => 'viewing','value' => MESSAGE_VIEW_SEARCH));
 144         echo html_writer::empty_tag('input', array('type' => 'submit','value' => $strmanagecontacts,'class' => $managebuttonclass));
 145         echo html_writer::end_tag('fieldset');
 146         echo html_writer::end_tag('form');
 147     }
 148
 149     echo html_writer::end_tag('div');
 150 }
 151
 152 /**
 153  * Print course participants. Called by message_print_contact_selector()
 154  *
 155  * @param object $context the course context
 156  * @param int $courseid the course ID
 157  * @param string $contactselecturl the url to send the user to when a contact's name is clicked
 158  * @param bool $showactionlinks show action links (add/remove contact etc) next to the users
 159  * @param string $titletodisplay Optionally specify a title to display above the participants
 160  * @param int $page if there are so many users listed that they have to be split into pages what page are we viewing
 161  * @param object $user2 the user $user1 is talking to. They will be highlighted if they appear in the list of participants
 162  * @return void
 163  */
 164 function message_print_participants($context, $courseid, $contactselecturl=null, $showactionlinks=true, $titletodisplay=null, $page=0, $user2=null) {
 165     global $DB, $USER, $PAGE, $OUTPUT;
 166
 167     if (empty($titletodisplay)) {
 168         $titletodisplay = get_string('participants');
 169     }
 170
 171     $countparticipants = count_enrolled_users($context);
 172
 173     list($esql, $params) = get_enrolled_sql($context);
 174     $params['mcuserid'] = $USER->id;
 175     $ufields = user_picture::fields('u');
 176
 177     $sql = "SELECT $ufields, mc.id as contactlistid, mc.blocked
 178               FROM {user} u
 179               JOIN ($esql) je ON je.id = u.id
 180               LEFT JOIN {message_contacts} mc ON mc.contactid = u.id AND mc.userid = :mcuserid
 181              WHERE u.deleted = 0";
 182
 183     $participants = $DB->get_records_sql($sql, $params, $page * MESSAGE_CONTACTS_PER_PAGE, MESSAGE_CONTACTS_PER_PAGE);
 184
 185     $pagingbar = new paging_bar($countparticipants, $page, MESSAGE_CONTACTS_PER_PAGE, $PAGE->url, 'page');
 186     echo $OUTPUT->render($pagingbar);
 187
 188     echo html_writer::start_tag('table', array('id' => 'message_participants', 'class' => 'boxaligncenter', 'cellspacing' => '2', 'cellpadding' => '0', 'border' => '0'));
 189
 190     echo html_writer::start_tag('tr');
 191     echo html_writer::tag('td', $titletodisplay, array('colspan' => 3, 'class' => 'heading'));
 192     echo html_writer::end_tag('tr');
 193
 194     foreach ($participants as $participant) {
 195         if ($participant->id != $USER->id) {
 196
 197             $iscontact = false;
 198             $isblocked = false;
 199             if ( $participant->contactlistid )  {
 200                 if ($participant->blocked == 0) {
 201                     // Is contact. Is not blocked.
 202                     $iscontact = true;
 203                     $isblocked = false;
 204                 } else {
 205                     // Is blocked.
 206                     $iscontact = false;
 207                     $isblocked = true;
 208                 }
 209             }
 210
 211             $participant->messagecount = 0;//todo it would be nice if the course participant could report new messages
 212             message_print_contactlist_user($participant, $iscontact, $isblocked, $contactselecturl, $showactionlinks, $user2);
 213         }
 214     }
 215
 216     echo html_writer::end_tag('table');
 217 }
 218
 219 /**
 220  * Retrieve users blocked by $user1
 221  *
 222  * @param object $user1 the user whose messages are being viewed
 223  * @param object $user2 the user $user1 is talking to. If they are being blocked
 224  *                      they will have a variable called 'isblocked' added to their user object
 225  * @return array the users blocked by $user1
 226  */
 227 function message_get_blocked_users($user1=null, $user2=null) {
 228     global $DB, $USER;
 229
 230     if (empty($user1)) {
 231         $user1 = $USER;
 232     }
 233
 234     if (!empty($user2)) {
 235         $user2->isblocked = false;
 236     }
 237
 238     $blockedusers = array();
 239
 240     $userfields = user_picture::fields('u', array('lastaccess'));
 241     $blockeduserssql = "SELECT $userfields, COUNT(m.id) AS messagecount
 242                           FROM {message_contacts} mc
 243                           JOIN {user} u ON u.id = mc.contactid
 244                           LEFT OUTER JOIN {message} m ON m.useridfrom = mc.contactid AND m.useridto = :user1id1
 245                          WHERE mc.userid = :user1id2 AND mc.blocked = 1
 246                       GROUP BY $userfields
 247                       ORDER BY u.firstname ASC";
 248     $rs =  $DB->get_recordset_sql($blockeduserssql, array('user1id1' => $user1->id, 'user1id2' => $user1->id));
 249
 250     foreach($rs as $rd) {
 251         $blockedusers[] = $rd;
 252
 253         if (!empty($user2) && $user2->id == $rd->id) {
 254             $user2->isblocked = true;
 255         }
 256     }
 257     $rs->close();
 258
 259     return $blockedusers;
 260 }
 261
 262 /**
 263  * Print users blocked by $user1. Called by message_print_contact_selector()
 264  *
 265  * @param array $blockedusers the users blocked by $user1
 266  * @param string $contactselecturl the url to send the user to when a contact's name is clicked
 267  * @param bool $showactionlinks show action links (add/remove contact etc) next to the users
 268  * @param string $titletodisplay Optionally specify a title to display above the participants
 269  * @param object $user2 the user $user1 is talking to. They will be highlighted if they appear in the list of blocked users
 270  * @return void
 271  */
 272 function message_print_blocked_users($blockedusers, $contactselecturl=null, $showactionlinks=true, $titletodisplay=null, $user2=null) {
 273     global $DB, $USER;
 274
 275     $countblocked = count($blockedusers);
 276
 277     echo html_writer::start_tag('table', array('id' => 'message_contacts', 'class' => 'boxaligncenter'));
 278
 279     if (!empty($titletodisplay)) {
 280         echo html_writer::start_tag('tr');
 281         echo html_writer::tag('td', $titletodisplay, array('colspan' => 3, 'class' => 'heading'));
 282         echo html_writer::end_tag('tr');
 283     }
 284
 285     if ($countblocked) {
 286         echo html_writer::start_tag('tr');
 287         echo html_writer::tag('td', get_string('blockedusers', 'message', $countblocked), array('colspan' => 3, 'class' => 'heading'));
 288         echo html_writer::end_tag('tr');
 289
 290         $isuserblocked = true;
 291         $isusercontact = false;
 292         foreach ($blockedusers as $blockeduser) {
 293             message_print_contactlist_user($blockeduser, $isusercontact, $isuserblocked, $contactselecturl, $showactionlinks, $user2);
 294         }
 295     }
 296
 297     echo html_writer::end_tag('table');
 298 }
 299
 300 /**
 301  * Retrieve $user1's contacts (online, offline and strangers)
 302  *
 303  * @param object $user1 the user whose messages are being viewed
 304  * @param object $user2 the user $user1 is talking to. If they are a contact
 305  *                      they will have a variable called 'iscontact' added to their user object
 306  * @return array containing 3 arrays. array($onlinecontacts, $offlinecontacts, $strangers)
 307  */
 308 function message_get_contacts($user1=null, $user2=null) {
 309     global $DB, $CFG, $USER;
 310
 311     if (empty($user1)) {
 312         $user1 = $USER;
 313     }
 314
 315     if (!empty($user2)) {
 316         $user2->iscontact = false;
 317     }
 318
 319     $timetoshowusers = 300; //Seconds default
 320     if (isset($CFG->block_online_users_timetosee)) {
 321         $timetoshowusers = $CFG->block_online_users_timetosee * 60;
 322     }
 323
 324     // time which a user is counting as being active since
 325     $timefrom = time()-$timetoshowusers;
 326
 327     // people in our contactlist who are online
 328     $onlinecontacts  = array();
 329     // people in our contactlist who are offline
 330     $offlinecontacts = array();
 331     // people who are not in our contactlist but have sent us a message
 332     $strangers       = array();
 333
 334     $userfields = user_picture::fields('u', array('lastaccess'));
 335
 336     // get all in our contactlist who are not blocked in our contact list
 337     // and count messages we have waiting from each of them
 338     $contactsql = "SELECT $userfields, COUNT(m.id) AS messagecount
 339                      FROM {message_contacts} mc
 340                      JOIN {user} u ON u.id = mc.contactid
 341                      LEFT OUTER JOIN {message} m ON m.useridfrom = mc.contactid AND m.useridto = ?
 342                     WHERE mc.userid = ? AND mc.blocked = 0
 343                  GROUP BY $userfields
 344                  ORDER BY u.firstname ASC";
 345
 346     $rs = $DB->get_recordset_sql($contactsql, array($user1->id, $user1->id));
 347     foreach ($rs as $rd) {
 348         if ($rd->lastaccess >= $timefrom) {
 349             // they have been active recently, so are counted online
 350             $onlinecontacts[] = $rd;
 351
 352         } else {
 353             $offlinecontacts[] = $rd;
 354         }
 355
 356         if (!empty($user2) && $user2->id == $rd->id) {
 357             $user2->iscontact = true;
 358         }
 359     }
 360     $rs->close();
 361
 362     // get messages from anyone who isn't in our contact list and count the number
 363     // of messages we have from each of them
 364     $strangersql = "SELECT $userfields, count(m.id) as messagecount
 365                       FROM {message} m
 366                       JOIN {user} u  ON u.id = m.useridfrom
 367                       LEFT OUTER JOIN {message_contacts} mc ON mc.contactid = m.useridfrom AND mc.userid = m.useridto
 368                      WHERE mc.id IS NULL AND m.useridto = ?
 369                   GROUP BY $userfields
 370                   ORDER BY u.firstname ASC";
 371
 372     $rs = $DB->get_recordset_sql($strangersql, array($USER->id));
 373     // Add user id as array index, so supportuser and noreply user don't get duplicated (if they are real users).
 374     foreach ($rs as $rd) {
 375         $strangers[$rd->id] = $rd;
 376     }
 377     $rs->close();
 378
 379     // Add noreply user and support user to the list, if they don't exist.
 380     $supportuser = core_user::get_support_user();
 381     if (!isset($strangers[$supportuser->id])) {
 382         $supportuser->messagecount = message_count_unread_messages($USER, $supportuser);
 383         if ($supportuser->messagecount > 0) {
 384             $strangers[$supportuser->id] = $supportuser;
 385         }
 386     }
 387
 388     $noreplyuser = core_user::get_noreply_user();
 389     if (!isset($strangers[$noreplyuser->id])) {
 390         $noreplyuser->messagecount = message_count_unread_messages($USER, $noreplyuser);
 391         if ($noreplyuser->messagecount > 0) {
 392             $strangers[$noreplyuser->id] = $noreplyuser;
 393         }
 394     }
 395     return array($onlinecontacts, $offlinecontacts, $strangers);
 396 }
 397
 398 /**
 399  * Print $user1's contacts. Called by message_print_contact_selector()
 400  *
 401  * @param array $onlinecontacts $user1's contacts which are online
 402  * @param array $offlinecontacts $user1's contacts which are offline
 403  * @param array $strangers users which are not contacts but who have messaged $user1
 404  * @param string $contactselecturl the url to send the user to when a contact's name is clicked
 405  * @param int $minmessages The minimum number of unread messages required from a user for them to be displayed
 406  *                         Typically 0 (show all contacts) or 1 (only show contacts from whom we have a new message)
 407  * @param bool $showactionlinks show action links (add/remove contact etc) next to the users
 408  * @param string $titletodisplay Optionally specify a title to display above the participants
 409  * @param object $user2 the user $user1 is talking to. They will be highlighted if they appear in the list of contacts
 410  * @return void
 411  */
 412 function message_print_contacts($onlinecontacts, $offlinecontacts, $strangers, $contactselecturl=null, $minmessages=0, $showactionlinks=true, $titletodisplay=null, $user2=null) {
 413     global $CFG, $PAGE, $OUTPUT;
 414
 415     $countonlinecontacts  = count($onlinecontacts);
 416     $countofflinecontacts = count($offlinecontacts);
 417     $countstrangers       = count($strangers);
 418     $isuserblocked = null;
 419
 420     if ($countonlinecontacts + $countofflinecontacts == 0) {
 421         echo html_writer::tag('div', get_string('contactlistempty', 'message'), array('class' => 'heading'));
 422     }
 423
 424     echo html_writer::start_tag('table', array('id' => 'message_contacts', 'class' => 'boxaligncenter'));
 425
 426     if (!empty($titletodisplay)) {
 427         message_print_heading($titletodisplay);
 428     }
 429
 430     if($countonlinecontacts) {
 431         // Print out list of online contacts.
 432
 433         if (empty($titletodisplay)) {
 434             message_print_heading(get_string('onlinecontacts', 'message', $countonlinecontacts));
 435         }
 436
 437         $isuserblocked = false;
 438         $isusercontact = true;
 439         foreach ($onlinecontacts as $contact) {
 440             if ($minmessages == 0 || $contact->messagecount >= $minmessages) {
 441                 message_print_contactlist_user($contact, $isusercontact, $isuserblocked, $contactselecturl, $showactionlinks, $user2);
 442             }
 443         }
 444     }
 445
 446     if ($countofflinecontacts) {
 447         // Print out list of offline contacts.
 448
 449         if (empty($titletodisplay)) {
 450             message_print_heading(get_string('offlinecontacts', 'message', $countofflinecontacts));
 451         }
 452
 453         $isuserblocked = false;
 454         $isusercontact = true;
 455         foreach ($offlinecontacts as $contact) {
 456             if ($minmessages == 0 || $contact->messagecount >= $minmessages) {
 457                 message_print_contactlist_user($contact, $isusercontact, $isuserblocked, $contactselecturl, $showactionlinks, $user2);
 458             }
 459         }
 460
 461     }
 462
 463     // Print out list of incoming contacts.
 464     if ($countstrangers) {
 465         message_print_heading(get_string('incomingcontacts', 'message', $countstrangers));
 466
 467         $isuserblocked = false;
 468         $isusercontact = false;
 469         foreach ($strangers as $stranger) {
 470             if ($minmessages == 0 || $stranger->messagecount >= $minmessages) {
 471                 message_print_contactlist_user($stranger, $isusercontact, $isuserblocked, $contactselecturl, $showactionlinks, $user2);
 472             }
 473         }
 474     }
 475
 476     echo html_writer::end_tag('table');
 477
 478     if ($countstrangers && ($countonlinecontacts + $countofflinecontacts == 0)) {  // Extra help
 479         echo html_writer::tag('div','('.get_string('addsomecontactsincoming', 'message').')',array('class' => 'note'));
 480     }
 481 }
 482
 483 /**
 484  * Print a select box allowing the user to choose to view new messages, course participants etc.
 485  *
 486  * Called by message_print_contact_selector()
 487  * @param int $viewing What page is the user viewing ie MESSAGE_VIEW_UNREAD_MESSAGES, MESSAGE_VIEW_RECENT_CONVERSATIONS etc
 488  * @param array $courses array of course objects. The courses the user is enrolled in.
 489  * @param array $coursecontexts array of course contexts. Keyed on course id.
 490  * @param int $countunreadtotal how many unread messages does the user have?
 491  * @param int $countblocked how many users has the current user blocked?
 492  * @param stdClass $user1 The user whose messages we are viewing.
 493  * @param string $strunreadmessages a preconstructed message about the number of unread messages the user has
 494  * @return void
 495  */
 496 function message_print_usergroup_selector($viewing, $courses, $coursecontexts, $countunreadtotal, $countblocked, $strunreadmessages, $user1 = null) {
 497     $options = array();
 498
 499     if ($countunreadtotal>0) { //if there are unread messages
 500         $options[MESSAGE_VIEW_UNREAD_MESSAGES] = $strunreadmessages;
 501     }
 502
 503     $str = get_string('contacts', 'message');
 504     $options[MESSAGE_VIEW_CONTACTS] = $str;
 505
 506     $options[MESSAGE_VIEW_RECENT_CONVERSATIONS] = get_string('mostrecentconversations', 'message');
 507     $options[MESSAGE_VIEW_RECENT_NOTIFICATIONS] = get_string('mostrecentnotifications', 'message');
 508
 509     if (!empty($courses)) {
 510         $courses_options = array();
 511
 512         foreach($courses as $course) {
 513             if (has_capability('moodle/course:viewparticipants', $coursecontexts[$course->id])) {
 514                 //Not using short_text() as we want the end of the course name. Not the beginning.
 515                 $shortname = format_string($course->shortname, true, array('context' => $coursecontexts[$course->id]));
 516                 if (core_text::strlen($shortname) > MESSAGE_MAX_COURSE_NAME_LENGTH) {
 517                     $courses_options[MESSAGE_VIEW_COURSE.$course->id] = '...'.core_text::substr($shortname, -MESSAGE_MAX_COURSE_NAME_LENGTH);
 518                 } else {
 519                     $courses_options[MESSAGE_VIEW_COURSE.$course->id] = $shortname;
 520                 }
 521             }
 522         }
 523
 524         if (!empty($courses_options)) {
 525             $options[] = array(get_string('courses') => $courses_options);
 526         }
 527     }
 528
 529     if ($countblocked>0) {
 530         $str = get_string('blockedusers','message', $countblocked);
 531         $options[MESSAGE_VIEW_BLOCKED] = $str;
 532     }
 533
 534     echo html_writer::start_tag('form', array('id' => 'usergroupform','method' => 'get','action' => ''));
 535     echo html_writer::start_tag('fieldset');
 536     if ( !empty($user1) && !empty($user1->id) ) {
 537         echo html_writer::empty_tag('input', array('type' => 'hidden','name' => 'user1','value' => $user1->id));
 538     }
 539     echo html_writer::label(get_string('messagenavigation', 'message'), 'viewing');
 540     echo html_writer::select($options, 'viewing', $viewing, false, array('id' => 'viewing','onchange' => 'this.form.submit()'));
 541     echo html_writer::end_tag('fieldset');
 542     echo html_writer::end_tag('form');
 543 }
 544
 545 /**
 546  * Load the course contexts for all of the users courses
 547  *
 548  * @param array $courses array of course objects. The courses the user is enrolled in.
 549  * @return array of course contexts
 550  */
 551 function message_get_course_contexts($courses) {
 552     $coursecontexts = array();
 553
 554     foreach($courses as $course) {
 555         $coursecontexts[$course->id] = context_course::instance($course->id);
 556     }
 557
 558     return $coursecontexts;
 559 }
 560
 561 /**
 562  * strip off action parameters like 'removecontact'
 563  *
 564  * @param moodle_url/string $moodleurl a URL. Typically the current page URL.
 565  * @return string the URL minus parameters that perform actions (like adding/removing/blocking a contact).
 566  */
 567 function message_remove_url_params($moodleurl) {
 568     $newurl = new moodle_url($moodleurl);
 569     $newurl->remove_params('addcontact','removecontact','blockcontact','unblockcontact');
 570     return $newurl->out();
 571 }
 572
 573 /**
 574  * Count the number of messages with a field having a specified value.
 575  * if $field is empty then return count of the whole array
 576  * if $field is non-existent then return 0
 577  *
 578  * @param array $messagearray array of message objects
 579  * @param string $field the field to inspect on the message objects
 580  * @param string $value the value to test the field against
 581  */
 582 function message_count_messages($messagearray, $field='', $value='') {
 583     if (!is_array($messagearray)) return 0;
 584     if ($field == '' or empty($messagearray)) return count($messagearray);
 585
 586     $count = 0;
 587     foreach ($messagearray as $message) {
 588         $count += ($message->$field == $value) ? 1 : 0;
 589     }
 590     return $count;
 591 }
 592
 593 /**
 594  * Returns the count of unread messages for user. Either from a specific user or from all users.
 595  *
 596  * @param object $user1 the first user. Defaults to $USER
 597  * @param object $user2 the second user. If null this function will count all of user 1's unread messages.
 598  * @return int the count of $user1's unread messages
 599  */
 600 function message_count_unread_messages($user1=null, $user2=null) {
 601     global $USER, $DB;
 602
 603     if (empty($user1)) {
 604         $user1 = $USER;
 605     }
 606
 607     if (!empty($user2)) {
 608         return $DB->count_records_select('message', "useridto = ? AND useridfrom = ?",
 609             array($user1->id, $user2->id), "COUNT('id')");
 610     } else {
 611         return $DB->count_records_select('message', "useridto = ?",
 612             array($user1->id), "COUNT('id')");
 613     }
 614 }
 615
 616 /**
 617  * Count the number of users blocked by $user1
 618  *
 619  * @param object $user1 user object
 620  * @return int the number of blocked users
 621  */
 622 function message_count_blocked_users($user1=null) {
 623     global $USER, $DB;
 624
 625     if (empty($user1)) {
 626         $user1 = $USER;
 627     }
 628
 629     $sql = "SELECT count(mc.id)
 630             FROM {message_contacts} mc
 631             WHERE mc.userid = :userid AND mc.blocked = 1";
 632     $params = array('userid' => $user1->id);
 633
 634     return $DB->count_records_sql($sql, $params);
 635 }
 636
 637 /**
 638  * Print the search form and search results if a search has been performed
 639  *
 640  * @param  boolean $advancedsearch show basic or advanced search form
 641  * @param  object $user1 the current user
 642  * @return boolean true if a search was performed
 643  */
 644 function message_print_search($advancedsearch = false, $user1=null) {
 645     $frm = data_submitted();
 646
 647     $doingsearch = false;
 648     if ($frm) {
 649         if (confirm_sesskey()) {
 650             $doingsearch = !empty($frm->combinedsubmit) || !empty($frm->keywords) || (!empty($frm->personsubmit) and !empty($frm->name));
 651         } else {
 652             $frm = false;
 653         }
 654     }
 655
 656     if (!empty($frm->combinedsearch)) {
 657         $combinedsearchstring = $frm->combinedsearch;
 658     } else {
 659         //$combinedsearchstring = get_string('searchcombined','message').'...';
 660         $combinedsearchstring = '';
 661     }
 662
 663     if ($doingsearch) {
 664         if ($advancedsearch) {
 665
 666             $messagesearch = '';
 667             if (!empty($frm->keywords)) {
 668                 $messagesearch = $frm->keywords;
 669             }
 670             $personsearch = '';
 671             if (!empty($frm->name)) {
 672                 $personsearch = $frm->name;
 673             }
 674             include('search_advanced.html');
 675         } else {
 676             include('search.html');
 677         }
 678
 679         $showicontext = false;
 680         message_print_search_results($frm, $showicontext, $user1);
 681
 682         return true;
 683     } else {
 684
 685         if ($advancedsearch) {
 686             $personsearch = $messagesearch = '';
 687             include('search_advanced.html');
 688         } else {
 689             include('search.html');
 690         }
 691         return false;
 692     }
 693 }
 694
 695 /**
 696  * Get the users recent conversations meaning all the people they've recently
 697  * sent or received a message from plus the most recent message sent to or received from each other user
 698  *
 699  * @param object $user the current user
 700  * @param int $limitfrom can be used for paging
 701  * @param int $limitto can be used for paging
 702  * @return array
 703  */
 704 function message_get_recent_conversations($user, $limitfrom=0, $limitto=100) {
 705     global $DB;
 706
 707     $userfields = user_picture::fields('u', array('lastaccess'));
 708     //This query retrieves the last message received from and sent to each user
 709     //It unions that data then, within that set, it finds the most recent message you've exchanged with each user over all
 710     //It then joins with some other tables to get some additional data we need
 711
 712     //message ID is used instead of timecreated as it should sort the same and will be much faster
 713
 714     //There is a separate query for read and unread queries as they are stored in different tables
 715     //They were originally retrieved in one query but it was so large that it was difficult to be confident in its correctness
 716     $sql = "SELECT $userfields, mr.id as mid, mr.notification, mr.smallmessage, mr.fullmessage, mr.fullmessagehtml, mr.fullmessageformat, mr.timecreated, mc.id as contactlistid, mc.blocked
 717               FROM {message_read} mr
 718               JOIN (
 719                     SELECT messages.userid AS userid, MAX(messages.mid) AS mid
 720                       FROM (
 721                            SELECT mr1.useridto AS userid, MAX(mr1.id) AS mid
 722                              FROM {message_read} mr1
 723                             WHERE mr1.useridfrom = :userid1
 724                                   AND mr1.notification = 0
 725                          GROUP BY mr1.useridto
 726                                   UNION
 727                            SELECT mr2.useridfrom AS userid, MAX(mr2.id) AS mid
 728                              FROM {message_read} mr2
 729                             WHERE mr2.useridto = :userid2
 730                                   AND mr2.notification = 0
 731                          GROUP BY mr2.useridfrom
 732                            ) messages
 733                   GROUP BY messages.userid
 734                    ) messages2 ON mr.id = messages2.mid AND (mr.useridto = messages2.userid OR mr.useridfrom = messages2.userid)
 735               JOIN {user} u ON u.id = messages2.userid
 736          LEFT JOIN {message_contacts} mc ON mc.userid = :userid3 AND mc.contactid = u.id
 737              WHERE u.deleted = '0'
 738           ORDER BY mr.id DESC";
 739     $params = array('userid1' => $user->id, 'userid2' => $user->id, 'userid3' => $user->id);
 740     $read =  $DB->get_records_sql($sql, $params, $limitfrom, $limitto);
 741
 742     $sql = "SELECT $userfields, m.id as mid, m.notification, m.smallmessage, m.fullmessage, m.fullmessagehtml, m.fullmessageformat, m.timecreated, mc.id as contactlistid, mc.blocked
 743               FROM {message} m
 744               JOIN (
 745                     SELECT messages.userid AS userid, MAX(messages.mid) AS mid
 746                       FROM (
 747                            SELECT m1.useridto AS userid, MAX(m1.id) AS mid
 748                              FROM {message} m1
 749                             WHERE m1.useridfrom = :userid1
 750                                   AND m1.notification = 0
 751                          GROUP BY m1.useridto
 752                                   UNION
 753                            SELECT m2.useridfrom AS userid, MAX(m2.id) AS mid
 754                              FROM {message} m2
 755                             WHERE m2.useridto = :userid2
 756                                   AND m2.notification = 0
 757                          GROUP BY m2.useridfrom
 758                            ) messages
 759                   GROUP BY messages.userid
 760                    ) messages2 ON m.id = messages2.mid AND (m.useridto = messages2.userid OR m.useridfrom = messages2.userid)
 761               JOIN {user} u ON u.id = messages2.userid
 762          LEFT JOIN {message_contacts} mc ON mc.userid = :userid3 AND mc.contactid = u.id
 763              WHERE u.deleted = '0'
 764              ORDER BY m.id DESC";
 765     $unread =  $DB->get_records_sql($sql, $params, $limitfrom, $limitto);
 766
 767     $conversations = array();
 768
 769     //Union the 2 result sets together looking for the message with the most recent timecreated for each other user
 770     //$conversation->id (the array key) is the other user's ID
 771     $conversation_arrays = array($unread, $read);
 772     foreach ($conversation_arrays as $conversation_array) {
 773         foreach ($conversation_array as $conversation) {
 774             if (empty($conversations[$conversation->id]) || $conversations[$conversation->id]->timecreated < $conversation->timecreated ) {
 775                 $conversations[$conversation->id] = $conversation;
 776             }
 777         }
 778     }
 779
 780     // Sort the conversations by $conversation->timecreated, newest to oldest
 781     // There may be multiple conversations with the same timecreated
 782     // The conversations array contains both read and unread messages (different tables) so sorting by ID won't work
 783     $result = core_collator::asort_objects_by_property($conversations, 'timecreated', core_collator::SORT_NUMERIC);
 784     $conversations = array_reverse($conversations);
 785
 786     return $conversations;
 787 }
 788
 789 /**
 790  * Get the users recent event notifications
 791  *
 792  * @param object $user the current user
 793  * @param int $limitfrom can be used for paging
 794  * @param int $limitto can be used for paging
 795  * @return array
 796  */
 797 function message_get_recent_notifications($user, $limitfrom=0, $limitto=100) {
 798     global $DB;
 799
 800     $userfields = user_picture::fields('u', array('lastaccess'));
 801     $sql = "SELECT mr.id AS message_read_id, $userfields, mr.notification, mr.smallmessage, mr.fullmessage, mr.fullmessagehtml, mr.fullmessageformat, mr.timecreated as timecreated, mr.contexturl, mr.contexturlname
 802               FROM {message_read} mr
 803                    JOIN {user} u ON u.id=mr.useridfrom
 804              WHERE mr.useridto = :userid1 AND u.deleted = '0' AND mr.notification = :notification
 805              ORDER BY mr.id DESC";//ordering by id should give the same result as ordering by timecreated but will be faster
 806     $params = array('userid1' => $user->id, 'notification' => 1);
 807
 808     $notifications =  $DB->get_records_sql($sql, $params, $limitfrom, $limitto);
 809     return $notifications;
 810 }
 811
 812 /**
 813  * Print the user's recent conversations
 814  *
 815  * @param stdClass $user the current user
 816  * @param bool $showicontext flag indicating whether or not to show text next to the action icons
 817  */
 818 function message_print_recent_conversations($user1 = null, $showicontext = false, $showactionlinks = true) {
 819     global $USER;
 820
 821     echo html_writer::start_tag('p', array('class' => 'heading'));
 822     echo get_string('mostrecentconversations', 'message');
 823     echo html_writer::end_tag('p');
 824
 825     if (empty($user1)) {
 826         $user1 = $USER;
 827     }
 828
 829     $conversations = message_get_recent_conversations($user1);
 830
 831     // Attach context url information to create the "View this conversation" type links
 832     foreach($conversations as $conversation) {
 833         $conversation->contexturl = new moodle_url("/message/index.php?user1={$user1->id}&user2={$conversation->id}");
 834         $conversation->contexturlname = get_string('thisconversation', 'message');
 835     }
 836
 837     $showotheruser = true;
 838     message_print_recent_messages_table($conversations, $user1, $showotheruser, $showicontext, false, $showactionlinks);
 839 }
 840
 841 /**
 842  * Print the user's recent notifications
 843  *
 844  * @param stdClass $user the current user
 845  */
 846 function message_print_recent_notifications($user=null) {
 847     global $USER;
 848
 849     echo html_writer::start_tag('p', array('class' => 'heading'));
 850     echo get_string('mostrecentnotifications', 'message');
 851     echo html_writer::end_tag('p');
 852
 853     if (empty($user)) {
 854         $user = $USER;
 855     }
 856
 857     $notifications = message_get_recent_notifications($user);
 858
 859     $showicontext = false;
 860     $showotheruser = false;
 861     message_print_recent_messages_table($notifications, $user, $showotheruser, $showicontext, true);
 862 }
 863
 864 /**
 865  * Print a list of recent messages
 866  *
 867  * @access private
 868  *
 869  * @param array $messages the messages to display
 870  * @param stdClass $user the current user
 871  * @param bool $showotheruser display information on the other user?
 872  * @param bool $showicontext show text next to the action icons?
 873  * @param bool $forcetexttohtml Force text to go through @see text_to_html() via @see format_text()
 874  * @param bool $showactionlinks
 875  * @return void
 876  */
 877 function message_print_recent_messages_table($messages, $user = null, $showotheruser = true, $showicontext = false, $forcetexttohtml = false, $showactionlinks = true) {
 878     global $OUTPUT;
 879     static $dateformat;
 880
 881     if (empty($dateformat)) {
 882         $dateformat = get_string('strftimedatetimeshort');
 883     }
 884
 885     echo html_writer::start_tag('div', array('class' => 'messagerecent'));
 886     foreach ($messages as $message) {
 887         echo html_writer::start_tag('div', array('class' => 'singlemessage'));
 888
 889         if ($showotheruser) {
 890             $strcontact = $strblock = $strhistory = null;
 891
 892             if ($showactionlinks) {
 893                 if ( $message->contactlistid )  {
 894                     if ($message->blocked == 0) { // The other user isn't blocked.
 895                         $strcontact = message_contact_link($message->id, 'remove', true, null, $showicontext);
 896                         $strblock   = message_contact_link($message->id, 'block', true, null, $showicontext);
 897                     } else { // The other user is blocked.
 898                         $strcontact = message_contact_link($message->id, 'add', true, null, $showicontext);
 899                         $strblock   = message_contact_link($message->id, 'unblock', true, null, $showicontext);
 900                     }
 901                 } else {
 902                     $strcontact = message_contact_link($message->id, 'add', true, null, $showicontext);
 903                     $strblock   = message_contact_link($message->id, 'block', true, null, $showicontext);
 904                 }
 905
 906                 //should we show just the icon or icon and text?
 907                 $histicontext = 'icon';
 908                 if ($showicontext) {
 909                     $histicontext = 'both';
 910                 }
 911                 $strhistory = message_history_link($user->id, $message->id, true, '', '', $histicontext);
 912             }
 913             echo html_writer::start_tag('span', array('class' => 'otheruser'));
 914
 915             echo html_writer::start_tag('span', array('class' => 'pix'));
 916             echo $OUTPUT->user_picture($message, array('size' => 20, 'courseid' => SITEID));
 917             echo html_writer::end_tag('span');
 918
 919             echo html_writer::start_tag('span', array('class' => 'contact'));
 920
 921             $link = new moodle_url("/message/index.php?user1={$user->id}&user2=$message->id");
 922             $action = null;
 923             echo $OUTPUT->action_link($link, fullname($message), $action, array('title' => get_string('sendmessageto', 'message', fullname($message))));
 924
 925             echo html_writer::end_tag('span');//end contact
 926
 927             if ($showactionlinks) {
 928                 echo $strcontact.$strblock.$strhistory;
 929             }
 930             echo html_writer::end_tag('span');//end otheruser
 931         }
 932
 933         $messagetext = message_format_message_text($message, $forcetexttohtml);
 934
 935         echo html_writer::tag('span', userdate($message->timecreated, $dateformat), array('class' => 'messagedate'));
 936         echo html_writer::tag('span', $messagetext, array('class' => 'themessage'));
 937         echo message_format_contexturl($message);
 938         echo html_writer::end_tag('div');//end singlemessage
 939     }
 940     echo html_writer::end_tag('div');//end messagerecent
 941 }
 942
 943 /**
 944  * Try to guess how to convert the message to html.
 945  *
 946  * @access private
 947  *
 948  * @param stdClass $message
 949  * @param bool $forcetexttohtml
 950  * @return string html fragment
 951  */
 952 function message_format_message_text($message, $forcetexttohtml = false) {
 953     // Note: this is a very nasty hack that tries to work around the weird messaging rules and design.
 954
 955     $options = new stdClass();
 956     $options->para = false;
 957
 958     $format = $message->fullmessageformat;
 959
 960     if ($message->smallmessage !== '') {
 961         if ($message->notification == 1) {
 962             if ($message->fullmessagehtml !== '' or $message->fullmessage !== '') {
 963                 $format = FORMAT_PLAIN;
 964             }
 965         }
 966         $messagetext = $message->smallmessage;
 967
 968     } else if ($message->fullmessageformat == FORMAT_HTML) {
 969         if ($message->fullmessagehtml !== '') {
 970             $messagetext = $message->fullmessagehtml;
 971         } else {
 972             $messagetext = $message->fullmessage;
 973             $format = FORMAT_MOODLE;
 974         }
 975
 976     } else {
 977         if ($message->fullmessage !== '') {
 978             $messagetext = $message->fullmessage;
 979         } else {
 980             $messagetext = $message->fullmessagehtml;
 981             $format = FORMAT_HTML;
 982         }
 983     }
 984
 985     if ($forcetexttohtml) {
 986         // This is a crazy hack, why not set proper format when creating the notifications?
 987         if ($format === FORMAT_PLAIN) {
 988             $format = FORMAT_MOODLE;
 989         }
 990     }
 991     return format_text($messagetext, $format, $options);
 992 }
 993
 994 /**
 995  * Add the selected user as a contact for the current user
 996  *
 997  * @param int $contactid the ID of the user to add as a contact
 998  * @param int $blocked 1 if you wish to block the contact
 999  * @return bool/int false if the $contactid isnt a valid user id. True if no changes made.
1000  *                  Otherwise returns the result of update_record() or insert_record()
1001  */
1002 function message_add_contact($contactid, $blocked=0) {
1003     global $USER, $DB;
1004
1005     if (!$DB->record_exists('user', array('id' => $contactid))) { // invalid userid
1006         return false;
1007     }
1008
1009     // Check if a record already exists as we may be changing blocking status.
1010     if (($contact = $DB->get_record('message_contacts', array('userid' => $USER->id, 'contactid' => $contactid))) !== false) {
1011         // Check if blocking status has been changed.
1012         if ($contact->blocked !== $blocked) {
1013             $contact->blocked = $blocked;
1014             $DB->update_record('message_contacts', $contact);
1015
1016             if ($blocked == 1) {
1017                 // Trigger event for blocking a contact.
1018                 $event = \core\event\message_contact_blocked::create(array(
1019                     'objectid' => $contact->id,
1020                     'userid' => $contact->userid,
1021                     'relateduserid' => $contact->contactid,
1022                     'context'  => context_user::instance($contact->userid)
1023                 ));
1024                 $event->add_record_snapshot('message_contacts', $contact);
1025                 $event->trigger();
1026             } else {
1027                 // Trigger event for unblocking a contact.
1028                 $event = \core\event\message_contact_unblocked::create(array(
1029                     'objectid' => $contact->id,
1030                     'userid' => $contact->userid,
1031                     'relateduserid' => $contact->contactid,
1032                     'context'  => context_user::instance($contact->userid)
1033                 ));
1034                 $event->add_record_snapshot('message_contacts', $contact);
1035                 $event->trigger();
1036             }
1037
1038             return true;
1039         } else {
1040             // No change to blocking status.
1041             return true;
1042         }
1043
1044     } else {
1045         // New contact record.
1046         $contact = new stdClass();
1047         $contact->userid = $USER->id;
1048         $contact->contactid = $contactid;
1049         $contact->blocked = $blocked;
1050         $contact->id = $DB->insert_record('message_contacts', $contact);
1051
1052         $eventparams = array(
1053             'objectid' => $contact->id,
1054             'userid' => $contact->userid,
1055             'relateduserid' => $contact->contactid,
1056             'context'  => context_user::instance($contact->userid)
1057         );
1058
1059         if ($blocked) {
1060             $event = \core\event\message_contact_blocked::create($eventparams);
1061         } else {
1062             $event = \core\event\message_contact_added::create($eventparams);
1063         }
1064         // Trigger event.
1065         $event->trigger();
1066
1067         return true;
1068     }
1069 }
1070
1071 /**
1072  * remove a contact
1073  *
1074  * @param int $contactid the user ID of the contact to remove
1075  * @return bool returns the result of delete_records()
1076  */
1077 function message_remove_contact($contactid) {
1078     global $USER, $DB;
1079
1080     if ($contact = $DB->get_record('message_contacts', array('userid' => $USER->id, 'contactid' => $contactid))) {
1081         $DB->delete_records('message_contacts', array('id' => $contact->id));
1082
1083         // Trigger event for removing a contact.
1084         $event = \core\event\message_contact_removed::create(array(
1085             'objectid' => $contact->id,
1086             'userid' => $contact->userid,
1087             'relateduserid' => $contact->contactid,
1088             'context'  => context_user::instance($contact->userid)
1089         ));
1090         $event->add_record_snapshot('message_contacts', $contact);
1091         $event->trigger();
1092
1093         return true;
1094     }
1095
1096     return false;
1097 }
1098
1099 /**
1100  * Unblock a contact. Note that this reverts the previously blocked user back to a non-contact.
1101  *
1102  * @param int $contactid the user ID of the contact to unblock
1103  * @return bool returns the result of delete_records()
1104  */
1105 function message_unblock_contact($contactid) {
1106     return message_add_contact($contactid, 0);
1107 }
1108
1109 /**
1110  * Block a user.
1111  *
1112  * @param int $contactid the user ID of the user to block
1113  * @return bool
1114  */
1115 function message_block_contact($contactid) {
1116     return message_add_contact($contactid, 1);
1117 }
1118
1119 /**
1120  * Load a user's contact record
1121  *
1122  * @param int $contactid the user ID of the user whose contact record you want
1123  * @return array message contacts
1124  */
1125 function message_get_contact($contactid) {
1126     global $USER, $DB;
1127     return $DB->get_record('message_contacts', array('userid' => $USER->id, 'contactid' => $contactid));
1128 }
1129
1130 /**
1131  * Print the results of a message search
1132  *
1133  * @param mixed $frm submitted form data
1134  * @param bool $showicontext show text next to action icons?
1135  * @param object $currentuser the current user
1136  * @return void
1137  */
1138 function message_print_search_results($frm, $showicontext=false, $currentuser=null) {
1139     global $USER, $DB, $OUTPUT;
1140
1141     if (empty($currentuser)) {
1142         $currentuser = $USER;
1143     }
1144
1145     echo html_writer::start_tag('div', array('class' => 'mdl-left'));
1146
1147     $personsearch = false;
1148     $personsearchstring = null;
1149     if (!empty($frm->personsubmit) and !empty($frm->name)) {
1150         $personsearch = true;
1151         $personsearchstring = $frm->name;
1152     } else if (!empty($frm->combinedsubmit) and !empty($frm->combinedsearch)) {
1153         $personsearch = true;
1154         $personsearchstring = $frm->combinedsearch;
1155     }
1156
1157     // Search for person.
1158     if ($personsearch) {
1159         if (optional_param('mycourses', 0, PARAM_BOOL)) {
1160             $users = array();
1161             $mycourses = enrol_get_my_courses('id');
1162             $mycoursesids = array();
1163             foreach ($mycourses as $mycourse) {
1164                 $mycoursesids[] = $mycourse->id;
1165             }
1166             $susers = message_search_users($mycoursesids, $personsearchstring);
1167             foreach ($susers as $suser) {
1168                 $users[$suser->id] = $suser;
1169             }
1170         } else {
1171             $users = message_search_users(SITEID, $personsearchstring);
1172         }
1173
1174         if (!empty($users)) {
1175             echo html_writer::start_tag('p', array('class' => 'heading searchresultcount'));
1176             echo get_string('userssearchresults', 'message', count($users));
1177             echo html_writer::end_tag('p');
1178
1179             echo html_writer::start_tag('table', array('class' => 'messagesearchresults'));
1180             foreach ($users as $user) {
1181
1182                 if ( $user->contactlistid )  {
1183                     if ($user->blocked == 0) { // User is not blocked.
1184                         $strcontact = message_contact_link($user->id, 'remove', true, null, $showicontext);
1185                         $strblock   = message_contact_link($user->id, 'block', true, null, $showicontext);
1186                     } else { // blocked
1187                         $strcontact = message_contact_link($user->id, 'add', true, null, $showicontext);
1188                         $strblock   = message_contact_link($user->id, 'unblock', true, null, $showicontext);
1189                     }
1190                 } else {
1191                     $strcontact = message_contact_link($user->id, 'add', true, null, $showicontext);
1192                     $strblock   = message_contact_link($user->id, 'block', true, null, $showicontext);
1193                 }
1194
1195                 // Should we show just the icon or icon and text?
1196                 $histicontext = 'icon';
1197                 if ($showicontext) {
1198                     $histicontext = 'both';
1199                 }
1200                 $strhistory = message_history_link($USER->id, $user->id, true, '', '', $histicontext);
1201
1202                 echo html_writer::start_tag('tr');
1203
1204                 echo html_writer::start_tag('td', array('class' => 'pix'));
1205                 echo $OUTPUT->user_picture($user, array('size' => 20, 'courseid' => SITEID));
1206                 echo html_writer::end_tag('td');
1207
1208                 echo html_writer::start_tag('td',array('class' => 'contact'));
1209                 $action = null;
1210                 $link = new moodle_url("/message/index.php?id=$user->id");
1211                 echo $OUTPUT->action_link($link, fullname($user), $action, array('title' => get_string('sendmessageto', 'message', fullname($user))));
1212                 echo html_writer::end_tag('td');
1213
1214                 echo html_writer::tag('td', $strcontact, array('class' => 'link'));
1215                 echo html_writer::tag('td', $strblock, array('class' => 'link'));
1216                 echo html_writer::tag('td', $strhistory, array('class' => 'link'));
1217
1218                 echo html_writer::end_tag('tr');
1219             }
1220             echo html_writer::end_tag('table');
1221
1222         } else {
1223             echo html_writer::start_tag('p', array('class' => 'heading searchresultcount'));
1224             echo get_string('userssearchresults', 'message', 0).'<br /><br />';
1225             echo html_writer::end_tag('p');
1226         }
1227     }
1228
1229     // search messages for keywords
1230     $messagesearch = false;
1231     $messagesearchstring = null;
1232     if (!empty($frm->keywords)) {
1233         $messagesearch = true;
1234         $messagesearchstring = clean_text(trim($frm->keywords));
1235     } else if (!empty($frm->combinedsubmit) and !empty($frm->combinedsearch)) {
1236         $messagesearch = true;
1237         $messagesearchstring = clean_text(trim($frm->combinedsearch));
1238     }
1239
1240     if ($messagesearch) {
1241         if ($messagesearchstring) {
1242             $keywords = explode(' ', $messagesearchstring);
1243         } else {
1244             $keywords = array();
1245         }
1246         $tome     = false;
1247         $fromme   = false;
1248         $courseid = 'none';
1249
1250         if (empty($frm->keywordsoption)) {
1251             $frm->keywordsoption = 'allmine';
1252         }
1253
1254         switch ($frm->keywordsoption) {
1255             case 'tome':
1256                 $tome   = true;
1257                 break;
1258             case 'fromme':
1259                 $fromme = true;
1260                 break;
1261             case 'allmine':
1262                 $tome   = true;
1263                 $fromme = true;
1264                 break;
1265             case 'allusers':
1266                 $courseid = SITEID;
1267                 break;
1268             case 'courseusers':
1269                 $courseid = $frm->courseid;
1270                 break;
1271             default:
1272                 $tome   = true;
1273                 $fromme = true;
1274         }
1275
1276         if (($messages = message_search($keywords, $fromme, $tome, $courseid)) !== false) {
1277
1278             // Get a list of contacts.
1279             if (($contacts = $DB->get_records('message_contacts', array('userid' => $USER->id), '', 'contactid, blocked') ) === false) {
1280                 $contacts = array();
1281             }
1282
1283             // Print heading with number of results.
1284             echo html_writer::start_tag('p', array('class' => 'heading searchresultcount'));
1285             $countresults = count($messages);
1286             if ($countresults == MESSAGE_SEARCH_MAX_RESULTS) {
1287                 echo get_string('keywordssearchresultstoomany', 'message', $countresults).' ("'.s($messagesearchstring).'")';
1288             } else {
1289                 echo get_string('keywordssearchresults', 'message', $countresults);
1290             }
1291             echo html_writer::end_tag('p');
1292
1293             // Print table headings.
1294             echo html_writer::start_tag('table', array('class' => 'messagesearchresults', 'cellspacing' => '0'));
1295
1296             $headertdstart = html_writer::start_tag('td', array('class' => 'messagesearchresultscol'));
1297             $headertdend   = html_writer::end_tag('td');
1298             echo html_writer::start_tag('tr');
1299             echo $headertdstart.get_string('from').$headertdend;
1300             echo $headertdstart.get_string('to').$headertdend;
1301             echo $headertdstart.get_string('message', 'message').$headertdend;
1302             echo $headertdstart.get_string('timesent', 'message').$headertdend;
1303             echo html_writer::end_tag('tr');
1304
1305             $blockedcount = 0;
1306             $dateformat = get_string('strftimedatetimeshort');
1307             $strcontext = get_string('context', 'message');
1308             foreach ($messages as $message) {
1309
1310                 // Ignore messages to and from blocked users unless $frm->includeblocked is set.
1311                 if (!optional_param('includeblocked', 0, PARAM_BOOL) and (
1312                       ( isset($contacts[$message->useridfrom]) and ($contacts[$message->useridfrom]->blocked == 1)) or
1313                       ( isset($contacts[$message->useridto]  ) and ($contacts[$message->useridto]->blocked   == 1))
1314                                                 )
1315                    ) {
1316                     $blockedcount ++;
1317                     continue;
1318                 }
1319
1320                 // Load user-to record.
1321                 if ($message->useridto !== $USER->id) {
1322                     $userto = core_user::get_user($message->useridto);
1323                     $tocontact = (array_key_exists($message->useridto, $contacts) and
1324                                     ($contacts[$message->useridto]->blocked == 0) );
1325                     $toblocked = (array_key_exists($message->useridto, $contacts) and
1326                                     ($contacts[$message->useridto]->blocked == 1) );
1327                 } else {
1328                     $userto = false;
1329                     $tocontact = false;
1330                     $toblocked = false;
1331                 }
1332
1333                 // Load user-from record.
1334                 if ($message->useridfrom !== $USER->id) {
1335                     $userfrom = core_user::get_user($message->useridfrom);
1336                     $fromcontact = (array_key_exists($message->useridfrom, $contacts) and
1337                                     ($contacts[$message->useridfrom]->blocked == 0) );
1338                     $fromblocked = (array_key_exists($message->useridfrom, $contacts) and
1339                                     ($contacts[$message->useridfrom]->blocked == 1) );
1340                 } else {
1341                     $userfrom = false;
1342                     $fromcontact = false;
1343                     $fromblocked = false;
1344                 }
1345
1346                 // Find date string for this message.
1347                 $date = usergetdate($message->timecreated);
1348                 $datestring = $date['year'].$date['mon'].$date['mday'];
1349
1350                 // Print out message row.
1351                 echo html_writer::start_tag('tr', array('valign' => 'top'));
1352
1353                 echo html_writer::start_tag('td', array('class' => 'contact'));
1354                 message_print_user($userfrom, $fromcontact, $fromblocked, $showicontext);
1355                 echo html_writer::end_tag('td');
1356
1357                 echo html_writer::start_tag('td', array('class' => 'contact'));
1358                 message_print_user($userto, $tocontact, $toblocked, $showicontext);
1359                 echo html_writer::end_tag('td');
1360
1361                 echo html_writer::start_tag('td', array('class' => 'summary'));
1362                 echo message_get_fragment($message->smallmessage, $keywords);
1363                 echo html_writer::start_tag('div', array('class' => 'link'));
1364
1365                 // If the user clicks the context link display message sender on the left.
1366                 // EXCEPT if the current user is in the conversation. Current user == always on the left.
1367                 $leftsideuserid = $rightsideuserid = null;
1368                 if ($currentuser->id == $message->useridto) {
1369                     $leftsideuserid = $message->useridto;
1370                     $rightsideuserid = $message->useridfrom;
1371                 } else {
1372                     $leftsideuserid = $message->useridfrom;
1373                     $rightsideuserid = $message->useridto;
1374                 }
1375                 message_history_link($leftsideuserid, $rightsideuserid, false,
1376                                      $messagesearchstring, 'm'.$message->id, $strcontext);
1377                 echo html_writer::end_tag('div');
1378                 echo html_writer::end_tag('td');
1379
1380                 echo html_writer::tag('td', userdate($message->timecreated, $dateformat), array('class' => 'date'));
1381
1382                 echo html_writer::end_tag('tr');
1383             }
1384
1385
1386             if ($blockedcount > 0) {
1387                 echo html_writer::start_tag('tr');
1388                 echo html_writer::tag('td', get_string('blockedmessages', 'message', $blockedcount), array('colspan' => 4, 'align' => 'center'));
1389                 echo html_writer::end_tag('tr');
1390             }
1391             echo html_writer::end_tag('table');
1392
1393         } else {
1394             echo html_writer::tag('p', get_string('keywordssearchresults', 'message', 0), array('class' => 'heading'));
1395         }
1396     }
1397
1398     if (!$personsearch && !$messagesearch) {
1399         //they didn't enter any search terms
1400         echo $OUTPUT->notification(get_string('emptysearchstring', 'message'));
1401     }
1402
1403     echo html_writer::end_tag('div');
1404 }
1405
1406 /**
1407  * Print information on a user. Used when printing search results.
1408  *
1409  * @param object/bool $user the user to display or false if you just want $USER
1410  * @param bool $iscontact is the user being displayed a contact?
1411  * @param bool $isblocked is the user being displayed blocked?
1412  * @param bool $includeicontext include text next to the action icons?
1413  * @return void
1414  */
1415 function message_print_user ($user=false, $iscontact=false, $isblocked=false, $includeicontext=false) {
1416     global $USER, $OUTPUT;
1417
1418     $userpictureparams = array('size' => 20, 'courseid' => SITEID);
1419
1420     if ($user === false) {
1421         echo $OUTPUT->user_picture($USER, $userpictureparams);
1422     } else if (core_user::is_real_user($user->id)) { // If not real user, then don't show any links.
1423         $userpictureparams['link'] = false;
1424         echo $OUTPUT->user_picture($USER, $userpictureparams);
1425         echo fullname($user);
1426     } else {
1427         echo $OUTPUT->user_picture($user, $userpictureparams);
1428
1429         $link = new moodle_url("/message/index.php?id=$user->id");
1430         echo $OUTPUT->action_link($link, fullname($user), null, array('title' =>
1431                 get_string('sendmessageto', 'message', fullname($user))));
1432
1433         $return = false;
1434         $script = null;
1435         if ($iscontact) {
1436             message_contact_link($user->id, 'remove', $return, $script, $includeicontext);
1437         } else {
1438             message_contact_link($user->id, 'add', $return, $script, $includeicontext);
1439         }
1440
1441         if ($isblocked) {
1442             message_contact_link($user->id, 'unblock', $return, $script, $includeicontext);
1443         } else {
1444             message_contact_link($user->id, 'block', $return, $script, $includeicontext);
1445         }
1446     }
1447 }
1448
1449 /**
1450  * Print a message contact link
1451  *
1452  * @param int $userid the ID of the user to apply to action to
1453  * @param string $linktype can be add, remove, block or unblock
1454  * @param bool $return if true return the link as a string. If false echo the link.
1455  * @param string $script the URL to send the user to when the link is clicked. If null, the current page.
1456  * @param bool $text include text next to the icons?
1457  * @param bool $icon include a graphical icon?
1458  * @return string  if $return is true otherwise bool
1459  */
1460 function message_contact_link($userid, $linktype='add', $return=false, $script=null, $text=false, $icon=true) {
1461     global $OUTPUT, $PAGE;
1462
1463     //hold onto the strings as we're probably creating a bunch of links
1464     static $str;
1465
1466     if (empty($script)) {
1467         //strip off previous action params like 'removecontact'
1468         $script = message_remove_url_params($PAGE->url);
1469     }
1470
1471     if (empty($str->blockcontact)) {
1472        $str = new stdClass();
1473        $str->blockcontact   =  get_string('blockcontact', 'message');
1474        $str->unblockcontact =  get_string('unblockcontact', 'message');
1475        $str->removecontact  =  get_string('removecontact', 'message');
1476        $str->addcontact     =  get_string('addcontact', 'message');
1477     }
1478
1479     $command = $linktype.'contact';
1480     $string  = $str->{$command};
1481
1482     $safealttext = s($string);
1483
1484     $safestring = '';
1485     if (!empty($text)) {
1486         $safestring = $safealttext;
1487     }
1488
1489     $img = '';
1490     if ($icon) {
1491         $iconpath = null;
1492         switch ($linktype) {
1493             case 'block':
1494                 $iconpath = 't/block';
1495                 break;
1496             case 'unblock':
1497                 $iconpath = 't/unblock';
1498                 break;
1499             case 'remove':
1500                 $iconpath = 't/removecontact';
1501                 break;
1502             case 'add':
1503             default:
1504                 $iconpath = 't/addcontact';
1505         }
1506
1507         $img = '<img src="'.$OUTPUT->pix_url($iconpath).'" class="iconsmall" alt="'.$safealttext.'" />';
1508     }
1509
1510     $output = '<span class="'.$linktype.'contact">'.
1511               '<a href="'.$script.'&amp;'.$command.'='.$userid.
1512               '&amp;sesskey='.sesskey().'" title="'.$safealttext.'">'.
1513               $img.
1514               $safestring.'</a></span>';
1515
1516     if ($return) {
1517         return $output;
1518     } else {
1519         echo $output;
1520         return true;
1521     }
1522 }
1523
1524 /**
1525  * echo or return a link to take the user to the full message history between themselves and another user
1526  *
1527  * @param int $userid1 the ID of the user displayed on the left (usually the current user)
1528  * @param int $userid2 the ID of the other user
1529  * @param bool $return true to return the link as a string. False to echo the link.
1530  * @param string $keywords any keywords to highlight in the message history
1531  * @param string $position anchor name to jump to within the message history
1532  * @param string $linktext optionally specify the link text
1533  * @return string|bool. Returns a string if $return is true. Otherwise returns a boolean.
1534  */
1535 function message_history_link($userid1, $userid2, $return=false, $keywords='', $position='', $linktext='') {
1536     global $OUTPUT, $PAGE;
1537     static $strmessagehistory;
1538
1539     if (empty($strmessagehistory)) {
1540         $strmessagehistory = get_string('messagehistory', 'message');
1541     }
1542
1543     if ($position) {
1544         $position = "#$position";
1545     }
1546     if ($keywords) {
1547         $keywords = "&search=".urlencode($keywords);
1548     }
1549
1550     if ($linktext == 'icon') {  // Icon only
1551         $fulllink = '<img src="'.$OUTPUT->pix_url('t/messages') . '" class="iconsmall" alt="'.$strmessagehistory.'" />';
1552     } else if ($linktext == 'both') {  // Icon and standard name
1553         $fulllink = '<img src="'.$OUTPUT->pix_url('t/messages') . '" class="iconsmall" alt="" />';
1554         $fulllink .= '&nbsp;'.$strmessagehistory;
1555     } else if ($linktext) {    // Custom name
1556         $fulllink = $linktext;
1557     } else {                   // Standard name only
1558         $fulllink = $strmessagehistory;
1559     }
1560
1561     $popupoptions = array(
1562             'height' => 500,
1563             'width' => 500,
1564             'menubar' => false,
1565             'location' => false,
1566             'status' => true,
1567             'scrollbars' => true,
1568             'resizable' => true);
1569
1570     $link = new moodle_url('/message/index.php?history='.MESSAGE_HISTORY_ALL."&user1=$userid1&user2=$userid2$keywords$position");
1571     if ($PAGE->url && $PAGE->url->get_param('viewing')) {
1572         $link->param('viewing', $PAGE->url->get_param('viewing'));
1573     }
1574     $action = null;
1575     $str = $OUTPUT->action_link($link, $fulllink, $action, array('title' => $strmessagehistory));
1576
1577     $str = '<span class="history">'.$str.'</span>';
1578
1579     if ($return) {
1580         return $str;
1581     } else {
1582         echo $str;
1583         return true;
1584     }
1585 }
1586
1587
1588 /**
1589  * Search through course users.
1590  *
1591  * If $courseids contains the site course then this function searches
1592  * through all undeleted and confirmed users.
1593  *
1594  * @param int|array $courseids Course ID or array of course IDs.
1595  * @param string $searchtext the text to search for.
1596  * @param string $sort the column name to order by.
1597  * @param string|array $exceptions comma separated list or array of user IDs to exclude.
1598  * @return array An array of {@link $USER} records.
1599  */
1600 function message_search_users($courseids, $searchtext, $sort='', $exceptions='') {
1601     global $CFG, $USER, $DB;
1602
1603     // Basic validation to ensure that the parameter $courseids is not an empty array or an empty value.
1604     if (!$courseids) {
1605         $courseids = array(SITEID);
1606     }
1607
1608     // Allow an integer to be passed.
1609     if (!is_array($courseids)) {
1610         $courseids = array($courseids);
1611     }
1612
1613     $fullname = $DB->sql_fullname();
1614     $ufields = user_picture::fields('u');
1615
1616     if (!empty($sort)) {
1617         $order = ' ORDER BY '. $sort;
1618     } else {
1619         $order = '';
1620     }
1621
1622     $params = array(
1623         'userid' => $USER->id,
1624         'query' => "%$searchtext%"
1625     );
1626
1627     if (empty($exceptions)) {
1628         $exceptions = array();
1629     } else if (!empty($exceptions) && is_string($exceptions)) {
1630         $exceptions = explode(',', $exceptions);
1631     }
1632
1633     // Ignore self and guest account.
1634     $exceptions[] = $USER->id;
1635     $exceptions[] = $CFG->siteguest;
1636
1637     // Exclude exceptions from the search result.
1638     list($except, $params_except) = $DB->get_in_or_equal($exceptions, SQL_PARAMS_NAMED, 'param', false);
1639     $except = ' AND u.id ' . $except;
1640     $params = array_merge($params_except, $params);
1641
1642     if (in_array(SITEID, $courseids)) {
1643         // Search on site level.
1644         return $DB->get_records_sql("SELECT $ufields, mc.id as contactlistid, mc.blocked
1645                                        FROM {user} u
1646                                        LEFT JOIN {message_contacts} mc
1647                                             ON mc.contactid = u.id AND mc.userid = :userid
1648                                       WHERE u.deleted = '0' AND u.confirmed = '1'
1649                                             AND (".$DB->sql_like($fullname, ':query', false).")
1650                                             $except
1651                                      $order", $params);
1652     } else {
1653         // Search in courses.
1654
1655         // Getting the context IDs or each course.
1656         $contextids = array();
1657         foreach ($courseids as $courseid) {
1658             $context = context_course::instance($courseid);
1659             $contextids = array_merge($contextids, $context->get_parent_context_ids(true));
1660         }
1661         list($contextwhere, $contextparams) = $DB->get_in_or_equal(array_unique($contextids), SQL_PARAMS_NAMED, 'context');
1662         $params = array_merge($params, $contextparams);
1663
1664         // Everyone who has a role assignment in this course or higher.
1665         // TODO: add enabled enrolment join here (skodak)
1666         $users = $DB->get_records_sql("SELECT DISTINCT $ufields, mc.id as contactlistid, mc.blocked
1667                                          FROM {user} u
1668                                          JOIN {role_assignments} ra ON ra.userid = u.id
1669                                          LEFT JOIN {message_contacts} mc
1670                                               ON mc.contactid = u.id AND mc.userid = :userid
1671                                         WHERE u.deleted = '0' AND u.confirmed = '1'
1672                                               AND (".$DB->sql_like($fullname, ':query', false).")
1673                                               AND ra.contextid $contextwhere
1674                                               $except
1675                                        $order", $params);
1676
1677         return $users;
1678     }
1679 }
1680
1681 /**
1682  * Search a user's messages
1683  *
1684  * Returns a list of posts found using an array of search terms
1685  * eg   word  +word -word
1686  *
1687  * @param array $searchterms an array of search terms (strings)
1688  * @param bool $fromme include messages from the user?
1689  * @param bool $tome include messages to the user?
1690  * @param mixed $courseid SITEID for admins searching all messages. Other behaviour not yet implemented
1691  * @param int $userid the user ID of the current user
1692  * @return mixed An array of messages or false if no matching messages were found
1693  */
1694 function message_search($searchterms, $fromme=true, $tome=true, $courseid='none', $userid=0) {
1695     global $CFG, $USER, $DB;
1696
1697     // If user is searching all messages check they are allowed to before doing anything else.
1698     if ($courseid == SITEID && !has_capability('moodle/site:readallmessages', context_system::instance())) {
1699         print_error('accessdenied','admin');
1700     }
1701
1702     // If no userid sent then assume current user.
1703     if ($userid == 0) $userid = $USER->id;
1704
1705     // Some differences in SQL syntax.
1706     if ($DB->sql_regex_supported()) {
1707         $REGEXP    = $DB->sql_regex(true);
1708         $NOTREGEXP = $DB->sql_regex(false);
1709     }
1710
1711     $searchcond = array();
1712     $params = array();
1713     $i = 0;
1714
1715     // Preprocess search terms to check whether we have at least 1 eligible search term.
1716     // If we do we can drop words around it like 'a'.
1717     $dropshortwords = false;
1718     foreach ($searchterms as $searchterm) {
1719         if (strlen($searchterm) >= 2) {
1720             $dropshortwords = true;
1721         }
1722     }
1723
1724     foreach ($searchterms as $searchterm) {
1725         $i++;
1726
1727         $NOT = false; // Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle.
1728
1729         if ($dropshortwords && strlen($searchterm) < 2) {
1730             continue;
1731         }
1732         // Under Oracle and MSSQL, trim the + and - operators and perform simpler LIKE search.
1733         if (!$DB->sql_regex_supported()) {
1734             if (substr($searchterm, 0, 1) == '-') {
1735                 $NOT = true;
1736             }
1737             $searchterm = trim($searchterm, '+-');
1738         }
1739
1740         if (substr($searchterm,0,1) == "+") {
1741             $searchterm = substr($searchterm,1);
1742             $searchterm = preg_quote($searchterm, '|');
1743             $searchcond[] = "m.fullmessage $REGEXP :ss$i";
1744             $params['ss'.$i] = "(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)";
1745
1746         } else if (substr($searchterm,0,1) == "-") {
1747             $searchterm = substr($searchterm,1);
1748             $searchterm = preg_quote($searchterm, '|');
1749             $searchcond[] = "m.fullmessage $NOTREGEXP :ss$i";
1750             $params['ss'.$i] = "(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)";
1751
1752         } else {
1753             $searchcond[] = $DB->sql_like("m.fullmessage", ":ss$i", false, true, $NOT);
1754             $params['ss'.$i] = "%$searchterm%";
1755         }
1756     }
1757
1758     if (empty($searchcond)) {
1759         $searchcond = " ".$DB->sql_like('m.fullmessage', ':ss1', false);
1760         $params['ss1'] = "%";
1761     } else {
1762         $searchcond = implode(" AND ", $searchcond);
1763     }
1764
1765     // There are several possibilities
1766     // 1. courseid = SITEID : The admin is searching messages by all users
1767     // 2. courseid = ??     : A teacher is searching messages by users in
1768     //                        one of their courses - currently disabled
1769     // 3. courseid = none   : User is searching their own messages;
1770     //    a.  Messages from user
1771     //    b.  Messages to user
1772     //    c.  Messages to and from user
1773
1774     if ($courseid == SITEID) { // Admin is searching all messages.
1775         $m_read   = $DB->get_records_sql("SELECT m.id, m.useridto, m.useridfrom, m.smallmessage, m.fullmessage, m.timecreated
1776                                             FROM {message_read} m
1777                                            WHERE $searchcond", $params, 0, MESSAGE_SEARCH_MAX_RESULTS);
1778         $m_unread = $DB->get_records_sql("SELECT m.id, m.useridto, m.useridfrom, m.smallmessage, m.fullmessage, m.timecreated
1779                                             FROM {message} m
1780                                            WHERE $searchcond", $params, 0, MESSAGE_SEARCH_MAX_RESULTS);
1781
1782     } else if ($courseid !== 'none') {
1783         // This has not been implemented due to security concerns.
1784         $m_read   = array();
1785         $m_unread = array();
1786
1787     } else {
1788
1789         if ($fromme and $tome) {
1790             $searchcond .= " AND (m.useridfrom=:userid1 OR m.useridto=:userid2)";
1791             $params['userid1'] = $userid;
1792             $params['userid2'] = $userid;
1793
1794         } else if ($fromme) {
1795             $searchcond .= " AND m.useridfrom=:userid";
1796             $params['userid'] = $userid;
1797
1798         } else if ($tome) {
1799             $searchcond .= " AND m.useridto=:userid";
1800             $params['userid'] = $userid;
1801         }
1802
1803         $m_read   = $DB->get_records_sql("SELECT m.id, m.useridto, m.useridfrom, m.smallmessage, m.fullmessage, m.timecreated
1804                                             FROM {message_read} m
1805                                            WHERE $searchcond", $params, 0, MESSAGE_SEARCH_MAX_RESULTS);
1806         $m_unread = $DB->get_records_sql("SELECT m.id, m.useridto, m.useridfrom, m.smallmessage, m.fullmessage, m.timecreated
1807                                             FROM {message} m
1808                                            WHERE $searchcond", $params, 0, MESSAGE_SEARCH_MAX_RESULTS);
1809
1810     }
1811
1812     /// The keys may be duplicated in $m_read and $m_unread so we can't
1813     /// do a simple concatenation
1814     $messages = array();
1815     foreach ($m_read as $m) {
1816         $messages[] = $m;
1817     }
1818     foreach ($m_unread as $m) {
1819         $messages[] = $m;
1820     }
1821
1822     return (empty($messages)) ? false : $messages;
1823 }
1824
1825 /**
1826  * Given a message object that we already know has a long message
1827  * this function truncates the message nicely to the first
1828  * sane place between $CFG->forum_longpost and $CFG->forum_shortpost
1829  *
1830  * @param string $message the message
1831  * @param int $minlength the minimum length to trim the message to
1832  * @return string the shortened message
1833  */
1834 function message_shorten_message($message, $minlength = 0) {
1835     $i = 0;
1836     $tag = false;
1837     $length = strlen($message);
1838     $count = 0;
1839     $stopzone = false;
1840     $truncate = 0;
1841     if ($minlength == 0) $minlength = MESSAGE_SHORTLENGTH;
1842
1843
1844     for ($i=0; $i<$length; $i++) {
1845         $char = $message[$i];
1846
1847         switch ($char) {
1848             case "<":
1849                 $tag = true;
1850                 break;
1851             case ">":
1852                 $tag = false;
1853                 break;
1854             default:
1855                 if (!$tag) {
1856                     if ($stopzone) {
1857                         if ($char == '.' or $char == ' ') {
1858                             $truncate = $i+1;
1859                             break 2;
1860                         }
1861                     }
1862                     $count++;
1863                 }
1864                 break;
1865         }
1866         if (!$stopzone) {
1867             if ($count > $minlength) {
1868                 $stopzone = true;
1869             }
1870         }
1871     }
1872
1873     if (!$truncate) {
1874         $truncate = $i;
1875     }
1876
1877     return substr($message, 0, $truncate);
1878 }
1879
1880
1881 /**
1882  * Given a string and an array of keywords, this function looks
1883  * for the first keyword in the string, and then chops out a
1884  * small section from the text that shows that word in context.
1885  *
1886  * @param string $message the text to search
1887  * @param array $keywords array of keywords to find
1888  */
1889 function message_get_fragment($message, $keywords) {
1890
1891     $fullsize = 160;
1892     $halfsize = (int)($fullsize/2);
1893
1894     $message = strip_tags($message);
1895
1896     foreach ($keywords as $keyword) {  // Just get the first one
1897         if ($keyword !== '') {
1898             break;
1899         }
1900     }
1901     if (empty($keyword)) {   // None found, so just return start of message
1902         return message_shorten_message($message, 30);
1903     }
1904
1905     $leadin = $leadout = '';
1906
1907 /// Find the start of the fragment
1908     $start = 0;
1909     $length = strlen($message);
1910
1911     $pos = strpos($message, $keyword);
1912     if ($pos > $halfsize) {
1913         $start = $pos - $halfsize;
1914         $leadin = '...';
1915     }
1916 /// Find the end of the fragment
1917     $end = $start + $fullsize;
1918     if ($end > $length) {
1919         $end = $length;
1920     } else {
1921         $leadout = '...';
1922     }
1923
1924 /// Pull out the fragment and format it
1925
1926     $fragment = substr($message, $start, $end - $start);
1927     $fragment = $leadin.highlight(implode(' ',$keywords), $fragment).$leadout;
1928     return $fragment;
1929 }
1930
1931 /**
1932  * Retrieve the messages between two users
1933  *
1934  * @param object $user1 the current user
1935  * @param object $user2 the other user
1936  * @param int $limitnum the maximum number of messages to retrieve
1937  * @param bool $viewingnewmessages are we currently viewing new messages?
1938  */
1939 function message_get_history($user1, $user2, $limitnum=0, $viewingnewmessages=false) {
1940     global $DB, $CFG;
1941
1942     $messages = array();
1943
1944     //we want messages sorted oldest to newest but if getting a subset of messages we need to sort
1945     //desc to get the last $limitnum messages then flip the order in php
1946     $sort = 'asc';
1947     if ($limitnum>0) {
1948         $sort = 'desc';
1949     }
1950
1951     $notificationswhere = null;
1952     //we have just moved new messages to read. If theyre here to see new messages dont hide notifications
1953     if (!$viewingnewmessages && $CFG->messaginghidereadnotifications) {
1954         $notificationswhere = 'AND notification=0';
1955     }
1956
1957     //prevent notifications of your own actions appearing in your own message history
1958     $ownnotificationwhere = ' AND NOT (useridfrom=? AND notification=1)';
1959
1960     if ($messages_read = $DB->get_records_select('message_read', "((useridto = ? AND useridfrom = ?) OR
1961                                                     (useridto = ? AND useridfrom = ?)) $notificationswhere $ownnotificationwhere",
1962                                                     array($user1->id, $user2->id, $user2->id, $user1->id, $user1->id),
1963                                                     "timecreated $sort", '*', 0, $limitnum)) {
1964         foreach ($messages_read as $message) {
1965             $messages[] = $message;
1966         }
1967     }
1968     if ($messages_new =  $DB->get_records_select('message', "((useridto = ? AND useridfrom = ?) OR
1969                                                     (useridto = ? AND useridfrom = ?)) $ownnotificationwhere",
1970                                                     array($user1->id, $user2->id, $user2->id, $user1->id, $user1->id),
1971                                                     "timecreated $sort", '*', 0, $limitnum)) {
1972         foreach ($messages_new as $message) {
1973             $messages[] = $message;
1974         }
1975     }
1976
1977     $result = core_collator::asort_objects_by_property($messages, 'timecreated', core_collator::SORT_NUMERIC);
1978
1979     //if we only want the last $limitnum messages
1980     $messagecount = count($messages);
1981     if ($limitnum > 0 && $messagecount > $limitnum) {
1982         $messages = array_slice($messages, $messagecount - $limitnum, $limitnum, true);
1983     }
1984
1985     return $messages;
1986 }
1987
1988 /**
1989  * Print the message history between two users
1990  *
1991  * @param object $user1 the current user
1992  * @param object $user2 the other user
1993  * @param string $search search terms to highlight
1994  * @param int $messagelimit maximum number of messages to return
1995  * @param string $messagehistorylink the html for the message history link or false
1996  * @param bool $viewingnewmessages are we currently viewing new messages?
1997  */
1998 function message_print_message_history($user1, $user2 ,$search = '', $messagelimit = 0, $messagehistorylink = false, $viewingnewmessages = false, $showactionlinks = true) {
1999     global $CFG, $OUTPUT;
2000
2001     echo $OUTPUT->box_start('center');
2002     echo html_writer::start_tag('table', array('cellpadding' => '10', 'class' => 'message_user_pictures'));
2003     echo html_writer::start_tag('tr');
2004
2005     echo html_writer::start_tag('td', array('align' => 'center', 'id' => 'user1'));
2006     echo $OUTPUT->user_picture($user1, array('size' => 100, 'courseid' => SITEID));
2007     echo html_writer::tag('div', fullname($user1), array('class' => 'heading'));
2008     echo html_writer::end_tag('td');
2009
2010     echo html_writer::start_tag('td', array('align' => 'center'));
2011     echo html_writer::empty_tag('img', array('src' => $OUTPUT->pix_url('i/twoway'), 'alt' => ''));
2012     echo html_writer::end_tag('td');
2013
2014     echo html_writer::start_tag('td', array('align' => 'center', 'id' => 'user2'));
2015     // Show user picture with link is real user else without link.
2016     if (core_user::is_real_user($user2->id)) {
2017         echo $OUTPUT->user_picture($user2, array('size' => 100, 'courseid' => SITEID));
2018     } else {
2019         echo $OUTPUT->user_picture($user2, array('size' => 100, 'courseid' => SITEID, 'link' => false));
2020     }
2021     echo html_writer::tag('div', fullname($user2), array('class' => 'heading'));
2022
2023     if ($showactionlinks && isset($user2->iscontact) && isset($user2->isblocked)) {
2024
2025         $script = null;
2026         $text = true;
2027         $icon = false;
2028
2029         $strcontact = message_get_contact_add_remove_link($user2->iscontact, $user2->isblocked, $user2, $script, $text, $icon);
2030         $strblock   = message_get_contact_block_link($user2->iscontact, $user2->isblocked, $user2, $script, $text, $icon);
2031         $useractionlinks = $strcontact.'&nbsp;|'.$strblock;
2032
2033         echo html_writer::tag('div', $useractionlinks, array('class' => 'useractionlinks'));
2034     }
2035
2036     echo html_writer::end_tag('td');
2037     echo html_writer::end_tag('tr');
2038     echo html_writer::end_tag('table');
2039     echo $OUTPUT->box_end();
2040
2041     if (!empty($messagehistorylink)) {
2042         echo $messagehistorylink;
2043     }
2044
2045     /// Get all the messages and print them
2046     if ($messages = message_get_history($user1, $user2, $messagelimit, $viewingnewmessages)) {
2047         $tablecontents = '';
2048
2049         $current = new stdClass();
2050         $current->mday = '';
2051         $current->month = '';
2052         $current->year = '';
2053         $messagedate = get_string('strftimetime');
2054         $blockdate   = get_string('strftimedaydate');
2055         foreach ($messages as $message) {
2056             if ($message->notification) {
2057                 $notificationclass = ' notification';
2058             } else {
2059                 $notificationclass = null;
2060             }
2061             $date = usergetdate($message->timecreated);
2062             if ($current->mday != $date['mday'] | $current->month != $date['month'] | $current->year != $date['year']) {
2063                 $current->mday = $date['mday'];
2064                 $current->month = $date['month'];
2065                 $current->year = $date['year'];
2066
2067                 $datestring = html_writer::empty_tag('a', array('name' => $date['year'].$date['mon'].$date['mday']));
2068                 $tablecontents .= html_writer::tag('div', $datestring, array('class' => 'mdl-align heading'));
2069
2070                 $tablecontents .= $OUTPUT->heading(userdate($message->timecreated, $blockdate), 4, 'mdl-align');
2071             }
2072
2073             $formatted_message = $side = null;
2074             if ($message->useridfrom == $user1->id) {
2075                 $formatted_message = message_format_message($message, $messagedate, $search, 'me');
2076                 $side = 'left';
2077             } else {
2078                 $formatted_message = message_format_message($message, $messagedate, $search, 'other');
2079                 $side = 'right';
2080             }
2081             $tablecontents .= html_writer::tag('div', $formatted_message, array('class' => "mdl-left $side $notificationclass"));
2082         }
2083
2084         echo html_writer::nonempty_tag('div', $tablecontents, array('class' => 'mdl-left messagehistory'));
2085     } else {
2086         echo html_writer::nonempty_tag('div', '('.get_string('nomessagesfound', 'message').')', array('class' => 'mdl-align messagehistory'));
2087     }
2088 }
2089
2090 /**
2091  * Format a message for display in the message history
2092  *
2093  * @param object $message the message object
2094  * @param string $format optional date format
2095  * @param string $keywords keywords to highlight
2096  * @param string $class CSS class to apply to the div around the message
2097  * @return string the formatted message
2098  */
2099 function message_format_message($message, $format='', $keywords='', $class='other') {
2100
2101     static $dateformat;
2102
2103     //if we haven't previously set the date format or they've supplied a new one
2104     if ( empty($dateformat) || (!empty($format) && $dateformat != $format) ) {
2105         if ($format) {
2106             $dateformat = $format;
2107         } else {
2108             $dateformat = get_string('strftimedatetimeshort');
2109         }
2110     }
2111     $time = userdate($message->timecreated, $dateformat);
2112
2113     $messagetext = message_format_message_text($message, false);
2114
2115     if ($keywords) {
2116         $messagetext = highlight($keywords, $messagetext);
2117     }
2118
2119     $messagetext .= message_format_contexturl($message);
2120
2121     $messagetext = clean_text($messagetext, FORMAT_HTML);
2122
2123     return <<<TEMPLATE
2124 <div class='message $class'>
2125     <a name="m{$message->id}"></a>
2126     <span class="message-meta"><span class="time">$time</span></span>: <span class="text">$messagetext</span>
2127 </div>
2128 TEMPLATE;
2129 }
2130
2131 /**
2132  * Format a the context url and context url name of a message for display
2133  *
2134  * @param object $message the message object
2135  * @return string the formatted string
2136  */
2137 function message_format_contexturl($message) {
2138     $s = null;
2139
2140     if (!empty($message->contexturl)) {
2141         $displaytext = null;
2142         if (!empty($message->contexturlname)) {
2143             $displaytext= $message->contexturlname;
2144         } else {
2145             $displaytext= $message->contexturl;
2146         }
2147         $s .= html_writer::start_tag('div',array('class' => 'messagecontext'));
2148             $s .= get_string('view').': '.html_writer::tag('a', $displaytext, array('href' => $message->contexturl));
2149         $s .= html_writer::end_tag('div');
2150     }
2151
2152     return $s;
2153 }
2154
2155 /**
2156  * Send a message from one user to another. Will be delivered according to the message recipients messaging preferences
2157  *
2158  * @param object $userfrom the message sender
2159  * @param object $userto the message recipient
2160  * @param string $message the message
2161  * @param int $format message format such as FORMAT_PLAIN or FORMAT_HTML
2162  * @return int|false the ID of the new message or false
2163  */
2164 function message_post_message($userfrom, $userto, $message, $format) {
2165     global $SITE, $CFG, $USER;
2166
2167     $eventdata = new stdClass();
2168     $eventdata->component        = 'moodle';
2169     $eventdata->name             = 'instantmessage';
2170     $eventdata->userfrom         = $userfrom;
2171     $eventdata->userto           = $userto;
2172
2173     //using string manager directly so that strings in the message will be in the message recipients language rather than the senders
2174     $eventdata->subject          = get_string_manager()->get_string('unreadnewmessage', 'message', fullname($userfrom), $userto->lang);
2175
2176     if ($format == FORMAT_HTML) {
2177         $eventdata->fullmessagehtml  = $message;
2178         //some message processors may revert to sending plain text even if html is supplied
2179         //so we keep both plain and html versions if we're intending to send html
2180         $eventdata->fullmessage = html_to_text($eventdata->fullmessagehtml);
2181     } else {
2182         $eventdata->fullmessage      = $message;
2183         $eventdata->fullmessagehtml  = '';
2184     }
2185
2186     $eventdata->fullmessageformat = $format;
2187     $eventdata->smallmessage     = $message;//store the message unfiltered. Clean up on output.
2188
2189     $s = new stdClass();
2190     $s->sitename = format_string($SITE->shortname, true, array('context' => context_course::instance(SITEID)));
2191     $s->url = $CFG->wwwroot.'/message/index.php?user='.$userto->id.'&id='.$userfrom->id;
2192
2193     $emailtagline = get_string_manager()->get_string('emailtagline', 'message', $s, $userto->lang);
2194     if (!empty($eventdata->fullmessage)) {
2195         $eventdata->fullmessage .= "\n\n---------------------------------------------------------------------\n".$emailtagline;
2196     }
2197     if (!empty($eventdata->fullmessagehtml)) {
2198         $eventdata->fullmessagehtml .= "<br /><br />---------------------------------------------------------------------<br />".$emailtagline;
2199     }
2200
2201     $eventdata->timecreated     = time();
2202     $eventdata->notification    = 0;
2203     return message_send($eventdata);
2204 }
2205
2206 /**
2207  * Print a row of contactlist displaying user picture, messages waiting and
2208  * block links etc
2209  *
2210  * @param object $contact contact object containing all fields required for $OUTPUT->user_picture()
2211  * @param bool $incontactlist is the user a contact of ours?
2212  * @param bool $isblocked is the user blocked?
2213  * @param string $selectcontacturl the url to send the user to when a contact's name is clicked
2214  * @param bool $showactionlinks display action links next to the other users (add contact, block user etc)
2215  * @param object $selecteduser the user the current user is viewing (if any). They will be highlighted.
2216  * @return void
2217  */
2218 function message_print_contactlist_user($contact, $incontactlist = true, $isblocked = false, $selectcontacturl = null, $showactionlinks = true, $selecteduser=null) {
2219     global $OUTPUT, $USER, $COURSE;
2220     $fullname  = fullname($contact);
2221     $fullnamelink  = $fullname;
2222
2223     $linkclass = '';
2224     if (!empty($selecteduser) && $contact->id == $selecteduser->id) {
2225         $linkclass = 'messageselecteduser';
2226     }
2227
2228     // Are there any unread messages for this contact?
2229     if ($contact->messagecount > 0 ){
2230         $fullnamelink = '<strong>'.$fullnamelink.' ('.$contact->messagecount.')</strong>';
2231     }
2232
2233     $strcontact = $strblock = $strhistory = null;
2234
2235     if ($showactionlinks) {
2236         // Show block and delete links if user is real user.
2237         if (core_user::is_real_user($contact->id)) {
2238             $strcontact = message_get_contact_add_remove_link($incontactlist, $isblocked, $contact);
2239             $strblock   = message_get_contact_block_link($incontactlist, $isblocked, $contact);
2240         }
2241         $strhistory = message_history_link($USER->id, $contact->id, true, '', '', 'icon');
2242     }
2243
2244     echo html_writer::start_tag('tr');
2245     echo html_writer::start_tag('td', array('class' => 'pix'));
2246     echo $OUTPUT->user_picture($contact, array('size' => 20, 'courseid' => $COURSE->id));
2247     echo html_writer::end_tag('td');
2248
2249     echo html_writer::start_tag('td', array('class' => 'contact'));
2250
2251     $popupoptions = array(
2252             'height' => MESSAGE_DISCUSSION_HEIGHT,
2253             'width' => MESSAGE_DISCUSSION_WIDTH,
2254             'menubar' => false,
2255             'location' => false,
2256             'status' => true,
2257             'scrollbars' => true,
2258             'resizable' => true);
2259
2260     $link = $action = null;
2261     if (!empty($selectcontacturl)) {
2262         $link = new moodle_url($selectcontacturl.'&user2='.$contact->id);
2263     } else {
2264         //can $selectcontacturl be removed and maybe the be removed and hardcoded?
2265         $link = new moodle_url("/message/index.php?id=$contact->id");
2266         $action = new popup_action('click', $link, "message_$contact->id", $popupoptions);
2267     }
2268     echo $OUTPUT->action_link($link, $fullnamelink, $action, array('class' => $linkclass,'title' => get_string('sendmessageto', 'message', $fullname)));
2269
2270     echo html_writer::end_tag('td');
2271
2272     echo html_writer::tag('td', '&nbsp;'.$strcontact.$strblock.'&nbsp;'.$strhistory, array('class' => 'link'));
2273
2274     echo html_writer::end_tag('tr');
2275 }
2276
2277 /**
2278  * Constructs the add/remove contact link to display next to other users
2279  *
2280  * @param bool $incontactlist is the user a contact
2281  * @param bool $isblocked is the user blocked
2282  * @param stdClass $contact contact object
2283  * @param string $script the URL to send the user to when the link is clicked. If null, the current page.
2284  * @param bool $text include text next to the icons?
2285  * @param bool $icon include a graphical icon?
2286  * @return string
2287  */
2288 function message_get_contact_add_remove_link($incontactlist, $isblocked, $contact, $script=null, $text=false, $icon=true) {
2289     $strcontact = '';
2290
2291     if($incontactlist){
2292         $strcontact = message_contact_link($contact->id, 'remove', true, $script, $text, $icon);
2293     } else if ($isblocked) {
2294         $strcontact = message_contact_link($contact->id, 'add', true, $script, $text, $icon);
2295     } else{
2296         $strcontact = message_contact_link($contact->id, 'add', true, $script, $text, $icon);
2297     }
2298
2299     return $strcontact;
2300 }
2301
2302 /**
2303  * Constructs the block contact link to display next to other users
2304  *
2305  * @param bool $incontactlist is the user a contact?
2306  * @param bool $isblocked is the user blocked?
2307  * @param stdClass $contact contact object
2308  * @param string $script the URL to send the user to when the link is clicked. If null, the current page.
2309  * @param bool $text include text next to the icons?
2310  * @param bool $icon include a graphical icon?
2311  * @return string
2312  */
2313 function message_get_contact_block_link($incontactlist, $isblocked, $contact, $script=null, $text=false, $icon=true) {
2314     $strblock   = '';
2315
2316     //commented out to allow the user to block a contact without having to remove them first
2317     /*if ($incontactlist) {
2318         //$strblock = '';
2319     } else*/
2320     if ($isblocked) {
2321         $strblock   = '&nbsp;'.message_contact_link($contact->id, 'unblock', true, $script, $text, $icon);
2322     } else{
2323         $strblock   = '&nbsp;'.message_contact_link($contact->id, 'block', true, $script, $text, $icon);
2324     }
2325
2326     return $strblock;
2327 }
2328
2329 /**
2330  * Moves messages from a particular user from the message table (unread messages) to message_read
2331  * This is typically only used when a user is deleted
2332  *
2333  * @param object $userid User id
2334  * @return boolean success
2335  */
2336 function message_move_userfrom_unread2read($userid) {
2337     global $DB;
2338
2339     // move all unread messages from message table to message_read
2340     if ($messages = $DB->get_records_select('message', 'useridfrom = ?', array($userid), 'timecreated')) {
2341         foreach ($messages as $message) {
2342             message_mark_message_read($message, 0); //set timeread to 0 as the message was never read
2343         }
2344     }
2345     return true;
2346 }
2347
2348 /**
2349  * marks ALL messages being sent from $fromuserid to $touserid as read
2350  *
2351  * @param int $touserid the id of the message recipient
2352  * @param int $fromuserid the id of the message sender
2353  * @return void
2354  */
2355 function message_mark_messages_read($touserid, $fromuserid){
2356     global $DB;
2357
2358     $sql = 'SELECT m.* FROM {message} m WHERE m.useridto=:useridto AND m.useridfrom=:useridfrom';
2359     $messages = $DB->get_recordset_sql($sql, array('useridto' => $touserid,'useridfrom' => $fromuserid));
2360
2361     foreach ($messages as $message) {
2362         message_mark_message_read($message, time());
2363     }
2364
2365     $messages->close();
2366 }
2367
2368 /**
2369  * Mark a single message as read
2370  *
2371  * @param stdClass $message An object with an object property ie $message->id which is an id in the message table
2372  * @param int $timeread the timestamp for when the message should be marked read. Usually time().
2373  * @param bool $messageworkingempty Is the message_working table already confirmed empty for this message?
2374  * @return int the ID of the message in the message_read table
2375  */
2376 function message_mark_message_read($message, $timeread, $messageworkingempty=false) {
2377     global $DB;
2378
2379     $message->timeread = $timeread;
2380
2381     $messageid = $message->id;
2382     unset($message->id);//unset because it will get a new id on insert into message_read
2383
2384     //If any processors have pending actions abort them
2385     if (!$messageworkingempty) {
2386         $DB->delete_records('message_working', array('unreadmessageid' => $messageid));
2387     }
2388     $messagereadid = $DB->insert_record('message_read', $message);
2389
2390     $DB->delete_records('message', array('id' => $messageid));
2391
2392     // Trigger event for reading a message.
2393     $event = \core\event\message_viewed::create(array(
2394         'objectid' => $messagereadid,
2395         'userid' => $message->useridto, // Using the user who read the message as they are the ones performing the action.
2396         'context'  => context_user::instance($message->useridto),
2397         'relateduserid' => $message->useridfrom,
2398         'other' => array(
2399             'messageid' => $messageid
2400         )
2401     ));
2402     $event->trigger();
2403
2404     return $messagereadid;
2405 }
2406
2407 /**
2408  * A helper function that prints a formatted heading
2409  *
2410  * @param string $title the heading to display
2411  * @param int $colspan
2412  * @return void
2413  */
2414 function message_print_heading($title, $colspan=3) {
2415     echo html_writer::start_tag('tr');
2416     echo html_writer::tag('td', $title, array('colspan' => $colspan, 'class' => 'heading'));
2417     echo html_writer::end_tag('tr');
2418 }
2419
2420 /**
2421  * Get all message processors, validate corresponding plugin existance and
2422  * system configuration
2423  *
2424  * @param bool $ready only return ready-to-use processors
2425  * @param bool $reset Reset list of message processors (used in unit tests)
2426  * @return mixed $processors array of objects containing information on message processors
2427  */
2428 function get_message_processors($ready = false, $reset = false) {
2429     global $DB, $CFG;
2430
2431     static $processors;
2432     if ($reset) {
2433         $processors = array();
2434     }
2435
2436     if (empty($processors)) {
2437         // Get all processors, ensure the name column is the first so it will be the array key
2438         $processors = $DB->get_records('message_processors', null, 'name DESC', 'name, id, enabled');
2439         foreach ($processors as &$processor){
2440             $processorfile = $CFG->dirroot. '/message/output/'.$processor->name.'/message_output_'.$processor->name.'.php';
2441             if (is_readable($processorfile)) {
2442                 include_once($processorfile);
2443                 $processclass = 'message_output_' . $processor->name;
2444                 if (class_exists($processclass)) {
2445                     $pclass = new $processclass();
2446                     $processor->object = $pclass;
2447                     $processor->configured = 0;
2448                     if ($pclass->is_system_configured()) {
2449                         $processor->configured = 1;
2450                     }
2451                     $processor->hassettings = 0;
2452                     if (is_readable($CFG->dirroot.'/message/output/'.$processor->name.'/settings.php')) {
2453                         $processor->hassettings = 1;
2454                     }
2455                     $processor->available = 1;
2456                 } else {
2457                     print_error('errorcallingprocessor', 'message');
2458                 }
2459             } else {
2460                 $processor->available = 0;
2461             }
2462         }
2463     }
2464     if ($ready) {
2465         // Filter out enabled and system_configured processors
2466         $readyprocessors = $processors;
2467         foreach ($readyprocessors as $readyprocessor) {
2468             if (!($readyprocessor->enabled && $readyprocessor->configured)) {
2469                 unset($readyprocessors[$readyprocessor->name]);
2470             }
2471         }
2472         return $readyprocessors;
2473     }
2474
2475     return $processors;
2476 }
2477
2478 /**
2479  * Get all message providers, validate their plugin existance and
2480  * system configuration
2481  *
2482  * @return mixed $processors array of objects containing information on message processors
2483  */
2484 function get_message_providers() {
2485     global $CFG, $DB;
2486
2487     $pluginman = core_plugin_manager::instance();
2488
2489     $providers = $DB->get_records('message_providers', null, 'name');
2490
2491     // Remove all the providers whose plugins are disabled or don't exist
2492     foreach ($providers as $providerid => $provider) {
2493         $plugin = $pluginman->get_plugin_info($provider->component);
2494         if ($plugin) {
2495             if ($plugin->get_status() === core_plugin_manager::PLUGIN_STATUS_MISSING) {
2496                 unset($providers[$providerid]);   // Plugins does not exist
2497                 continue;
2498             }
2499             if ($plugin->is_enabled() === false) {
2500                 unset($providers[$providerid]);   // Plugin disabled
2501                 continue;
2502             }
2503         }
2504     }
2505     return $providers;
2506 }
2507
2508 /**
2509  * Get an instance of the message_output class for one of the output plugins.
2510  * @param string $type the message output type. E.g. 'email' or 'jabber'.
2511  * @return message_output message_output the requested class.
2512  */
2513 function get_message_processor($type) {
2514     global $CFG;
2515
2516     // Note, we cannot use the get_message_processors function here, becaues this
2517     // code is called during install after installing each messaging plugin, and
2518     // get_message_processors caches the list of installed plugins.
2519
2520     $processorfile = $CFG->dirroot . "/message/output/{$type}/message_output_{$type}.php";
2521     if (!is_readable($processorfile)) {
2522         throw new coding_exception('Unknown message processor type ' . $type);
2523     }
2524
2525     include_once($processorfile);
2526
2527     $processclass = 'message_output_' . $type;
2528     if (!class_exists($processclass)) {
2529         throw new coding_exception('Message processor ' . $type .
2530                 ' does not define the right class');
2531     }
2532
2533     return new $processclass();
2534 }
2535
2536 /**
2537  * Get messaging outputs default (site) preferences
2538  *
2539  * @return object $processors object containing information on message processors
2540  */
2541 function get_message_output_default_preferences() {
2542     return get_config('message');
2543 }
2544
2545 /**
2546  * Translate message default settings from binary value to the array of string
2547  * representing the settings to be stored. Also validate the provided value and
2548  * use default if it is malformed.
2549  *
2550  * @param  int    $plugindefault Default setting suggested by plugin
2551  * @param  string $processorname The name of processor
2552  * @return array  $settings array of strings in the order: $permitted, $loggedin, $loggedoff.
2553  */
2554 function translate_message_default_setting($plugindefault, $processorname) {
2555     // Preset translation arrays
2556     $permittedvalues = array(
2557         0x04 => 'disallowed',
2558         0x08 => 'permitted',
2559         0x0c => 'forced',
2560     );
2561
2562     $loggedinstatusvalues = array(
2563         0x00 => null, // use null if loggedin/loggedoff is not defined
2564         0x01 => 'loggedin',
2565         0x02 => 'loggedoff',
2566     );
2567
2568     // define the default setting
2569     $processor = get_message_processor($processorname);
2570     $default = $processor->get_default_messaging_settings();
2571
2572     // Validate the value. It should not exceed the maximum size
2573     if (!is_int($plugindefault) || ($plugindefault > 0x0f)) {
2574         debugging(get_string('errortranslatingdefault', 'message'));
2575         $plugindefault = $default;
2576     }
2577     // Use plugin default setting of 'permitted' is 0
2578     if (!($plugindefault & MESSAGE_PERMITTED_MASK)) {
2579         $plugindefault = $default;
2580     }
2581
2582     $permitted = $permittedvalues[$plugindefault & MESSAGE_PERMITTED_MASK];
2583     $loggedin = $loggedoff = null;
2584
2585     if (($plugindefault & MESSAGE_PERMITTED_MASK) == MESSAGE_PERMITTED) {
2586         $loggedin = $loggedinstatusvalues[$plugindefault & MESSAGE_DEFAULT_LOGGEDIN];
2587         $loggedoff = $loggedinstatusvalues[$plugindefault & MESSAGE_DEFAULT_LOGGEDOFF];
2588     }
2589
2590     return array($permitted, $loggedin, $loggedoff);
2591 }
2592
2593 /**
2594  * Return a list of page types
2595  * @param string $pagetype current page type
2596  * @param stdClass $parentcontext Block's parent context
2597  * @param stdClass $currentcontext Current context of block
2598  */
2599 function message_page_type_list($pagetype, $parentcontext, $currentcontext) {
2600     return array('messages-*'=>get_string('page-message-x', 'message'));
2601 }
2602
2603 /**
2604  * Is $USER one of the supplied users?
2605  *
2606  * $user2 will be null if viewing a user's recent conversations
2607  *
2608  * @param stdClass the first user
2609  * @param stdClass the second user or null
2610  * @return bool True if the current user is one of either $user1 or $user2
2611  */
2612 function message_current_user_is_involved($user1, $user2) {
2613     global $USER;
2614
2615     if (empty($user1->id) || (!empty($user2) && empty($user2->id))) {
2616         throw new coding_exception('Invalid user object detected. Missing id.');
2617     }
2618
2619     if ($user1->id != $USER->id && (empty($user2) || $user2->id != $USER->id)) {
2620         return false;
2621     }
2622     return true;
2623 }