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See Release Notes

  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
/blog/ -> locallib.php (source)

Differences Between: [Versions 310 and 311] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   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   * Classes for Blogs.
  19   *
  20   * @package    moodlecore
  21   * @subpackage blog
  22   * @copyright  2009 Nicolas Connault
  23   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24   */
  25  
  26  defined('MOODLE_INTERNAL') || die();
  27  
  28  require_once($CFG->libdir . '/filelib.php');
  29  
  30  /**
  31   * Blog_entry class. Represents an entry in a user's blog. Contains all methods for managing this entry.
  32   * This class does not contain any HTML-generating code. See blog_listing sub-classes for such code.
  33   * This class follows the Object Relational Mapping technique, its member variables being mapped to
  34   * the fields of the post table.
  35   *
  36   * @package    moodlecore
  37   * @subpackage blog
  38   * @copyright  2009 Nicolas Connault
  39   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  40   */
  41  class blog_entry implements renderable {
  42      // Public Database fields.
  43      public $id;
  44      public $userid;
  45      public $subject;
  46      public $summary;
  47      public $rating = 0;
  48      public $attachment;
  49      public $publishstate;
  50  
  51      // Locked Database fields (Don't touch these).
  52      public $courseid = 0;
  53      public $groupid = 0;
  54      public $module = 'blog';
  55      public $moduleid = 0;
  56      public $coursemoduleid = 0;
  57      public $content;
  58      public $format = 1;
  59      public $uniquehash = '';
  60      public $lastmodified;
  61      public $created;
  62      public $usermodified;
  63  
  64      // Other class variables.
  65      public $form;
  66      public $tags = array();
  67  
  68      /** @var StdClass Data needed to render the entry */
  69      public $renderable;
  70  
  71      /**
  72       * Constructor. If given an id, will fetch the corresponding record from the DB.
  73       *
  74       * @param mixed $idorparams A blog entry id if INT, or data for a new entry if array
  75       */
  76      public function __construct($id=null, $params=null, $form=null) {
  77          global $DB, $PAGE, $CFG;
  78  
  79          if (!empty($id)) {
  80              $object = $DB->get_record('post', array('id' => $id));
  81              foreach ($object as $var => $val) {
  82                  $this->$var = $val;
  83              }
  84          } else if (!empty($params) && (is_array($params) || is_object($params))) {
  85              foreach ($params as $var => $val) {
  86                  $this->$var = $val;
  87              }
  88          }
  89  
  90          if (!empty($CFG->useblogassociations)) {
  91              $associations = $DB->get_records('blog_association', array('blogid' => $this->id));
  92              foreach ($associations as $association) {
  93                  $context = context::instance_by_id($association->contextid);
  94                  if ($context->contextlevel == CONTEXT_COURSE) {
  95                      $this->courseassoc = $association->contextid;
  96                  } else if ($context->contextlevel == CONTEXT_MODULE) {
  97                      $this->modassoc = $association->contextid;
  98                  }
  99              }
 100          }
 101  
 102          $this->form = $form;
 103      }
 104  
 105  
 106      /**
 107       * Gets the required data to print the entry
 108       */
 109      public function prepare_render() {
 110  
 111          global $DB, $CFG, $PAGE;
 112  
 113          $this->renderable = new StdClass();
 114  
 115          $this->renderable->user = $DB->get_record('user', array('id' => $this->userid));
 116  
 117          // Entry comments.
 118          if (!empty($CFG->usecomments) and $CFG->blogusecomments) {
 119              require_once($CFG->dirroot . '/comment/lib.php');
 120  
 121              $cmt = new stdClass();
 122              $cmt->context = context_user::instance($this->userid);
 123              $cmt->courseid = $PAGE->course->id;
 124              $cmt->area = 'format_blog';
 125              $cmt->itemid = $this->id;
 126              $cmt->showcount = $CFG->blogshowcommentscount;
 127              $cmt->component = 'blog';
 128              $this->renderable->comment = new comment($cmt);
 129          }
 130  
 131          $this->summary = file_rewrite_pluginfile_urls($this->summary, 'pluginfile.php', SYSCONTEXTID, 'blog', 'post', $this->id);
 132  
 133          // External blog link.
 134          if ($this->uniquehash && $this->content) {
 135              if ($externalblog = $DB->get_record('blog_external', array('id' => $this->content))) {
 136                  $urlparts = parse_url($externalblog->url);
 137                  $this->renderable->externalblogtext = get_string('retrievedfrom', 'blog') . get_string('labelsep', 'langconfig');
 138                  $this->renderable->externalblogtext .= html_writer::link($urlparts['scheme'] . '://' . $urlparts['host'],
 139                                                                           $externalblog->name);
 140              }
 141          }
 142  
 143          // Retrieve associations.
 144          $this->renderable->unassociatedentry = false;
 145          if (!empty($CFG->useblogassociations)) {
 146  
 147              // Adding the entry associations data.
 148              if ($associations = $associations = $DB->get_records('blog_association', array('blogid' => $this->id))) {
 149  
 150                  // Check to see if the entry is unassociated with group/course level access.
 151                  if ($this->publishstate == 'group' || $this->publishstate == 'course') {
 152                      $this->renderable->unassociatedentry = true;
 153                  }
 154  
 155                  foreach ($associations as $key => $assocrec) {
 156  
 157                      if (!$context = context::instance_by_id($assocrec->contextid, IGNORE_MISSING)) {
 158                          unset($associations[$key]);
 159                          continue;
 160                      }
 161  
 162                      // The renderer will need the contextlevel of the association.
 163                      $associations[$key]->contextlevel = $context->contextlevel;
 164  
 165                      // Course associations.
 166                      if ($context->contextlevel == CONTEXT_COURSE) {
 167                          // TODO: performance!!!!
 168                          $instancename = $DB->get_field('course', 'shortname', array('id' => $context->instanceid));
 169  
 170                          $associations[$key]->url = $assocurl = new moodle_url('/course/view.php',
 171                                                                                array('id' => $context->instanceid));
 172                          $associations[$key]->text = $instancename;
 173                          $associations[$key]->icon = new pix_icon('i/course', $associations[$key]->text);
 174                      }
 175  
 176                      // Mod associations.
 177                      if ($context->contextlevel == CONTEXT_MODULE) {
 178  
 179                          // Getting the activity type and the activity instance id.
 180                          $sql = 'SELECT cm.instance, m.name FROM {course_modules} cm
 181                                    JOIN {modules} m ON m.id = cm.module
 182                                   WHERE cm.id = :cmid';
 183                          $modinfo = $DB->get_record_sql($sql, array('cmid' => $context->instanceid));
 184                          // TODO: performance!!!!
 185                          $instancename = $DB->get_field($modinfo->name, 'name', array('id' => $modinfo->instance));
 186  
 187                          $associations[$key]->type = get_string('modulename', $modinfo->name);
 188                          $associations[$key]->url = new moodle_url('/mod/' . $modinfo->name . '/view.php',
 189                                                                    array('id' => $context->instanceid));
 190                          $associations[$key]->text = $instancename;
 191                          $associations[$key]->icon = new pix_icon('icon', $associations[$key]->text, $modinfo->name);
 192                      }
 193                  }
 194              }
 195              $this->renderable->blogassociations = $associations;
 196          }
 197  
 198          // Entry attachments.
 199          $this->renderable->attachments = $this->get_attachments();
 200  
 201          $this->renderable->usercanedit = blog_user_can_edit_entry($this);
 202      }
 203  
 204  
 205      /**
 206       * Gets the entry attachments list
 207       * @return array List of blog_entry_attachment instances
 208       */
 209      public function get_attachments() {
 210  
 211          global $CFG;
 212  
 213          require_once($CFG->libdir.'/filelib.php');
 214  
 215          $syscontext = context_system::instance();
 216  
 217          $fs = get_file_storage();
 218          $files = $fs->get_area_files($syscontext->id, 'blog', 'attachment', $this->id);
 219  
 220          // Adding a blog_entry_attachment for each non-directory file.
 221          $attachments = array();
 222          foreach ($files as $file) {
 223              if ($file->is_directory()) {
 224                  continue;
 225              }
 226              $attachments[] = new blog_entry_attachment($file, $this->id);
 227          }
 228  
 229          return $attachments;
 230      }
 231  
 232      /**
 233       * Inserts this entry in the database. Access control checks must be done by calling code.
 234       *
 235       * @param mform $form Used for attachments
 236       * @return void
 237       */
 238      public function process_attachment($form) {
 239          $this->form = $form;
 240      }
 241  
 242      /**
 243       * Inserts this entry in the database. Access control checks must be done by calling code.
 244       * TODO Set the publishstate correctly
 245       * @return void
 246       */
 247      public function add() {
 248          global $CFG, $USER, $DB;
 249  
 250          unset($this->id);
 251          $this->module       = 'blog';
 252          $this->userid       = (empty($this->userid)) ? $USER->id : $this->userid;
 253          $this->lastmodified = time();
 254          $this->created      = time();
 255  
 256          // Insert the new blog entry.
 257          $this->id = $DB->insert_record('post', $this);
 258  
 259          if (!empty($CFG->useblogassociations)) {
 260              $this->add_associations();
 261          }
 262  
 263          core_tag_tag::set_item_tags('core', 'post', $this->id, context_user::instance($this->userid), $this->tags);
 264  
 265          // Trigger an event for the new entry.
 266          $event = \core\event\blog_entry_created::create(array(
 267              'objectid'      => $this->id,
 268              'relateduserid' => $this->userid
 269          ));
 270          $event->set_blog_entry($this);
 271          $event->trigger();
 272      }
 273  
 274      /**
 275       * Updates this entry in the database. Access control checks must be done by calling code.
 276       *
 277       * @param array       $params            Entry parameters.
 278       * @param moodleform  $form              Used for attachments.
 279       * @param array       $summaryoptions    Summary options.
 280       * @param array       $attachmentoptions Attachment options.
 281       *
 282       * @return void
 283       */
 284      public function edit($params=array(), $form=null, $summaryoptions=array(), $attachmentoptions=array()) {
 285          global $CFG, $DB;
 286  
 287          $sitecontext = context_system::instance();
 288          $entry = $this;
 289  
 290          $this->form = $form;
 291          foreach ($params as $var => $val) {
 292              $entry->$var = $val;
 293          }
 294  
 295          $entry = file_postupdate_standard_editor($entry, 'summary', $summaryoptions, $sitecontext, 'blog', 'post', $entry->id);
 296          $entry = file_postupdate_standard_filemanager($entry,
 297                                                        'attachment',
 298                                                        $attachmentoptions,
 299                                                        $sitecontext,
 300                                                        'blog',
 301                                                        'attachment',
 302                                                        $entry->id);
 303  
 304          if (!empty($CFG->useblogassociations)) {
 305              $entry->add_associations();
 306          }
 307  
 308          $entry->lastmodified = time();
 309  
 310          // Update record.
 311          $DB->update_record('post', $entry);
 312          core_tag_tag::set_item_tags('core', 'post', $entry->id, context_user::instance($this->userid), $entry->tags);
 313  
 314          $event = \core\event\blog_entry_updated::create(array(
 315              'objectid'      => $entry->id,
 316              'relateduserid' => $entry->userid
 317          ));
 318          $event->set_blog_entry($entry);
 319          $event->trigger();
 320      }
 321  
 322      /**
 323       * Deletes this entry from the database. Access control checks must be done by calling code.
 324       *
 325       * @return void
 326       */
 327      public function delete() {
 328          global $DB;
 329  
 330          $this->delete_attachments();
 331          $this->remove_associations();
 332  
 333          // Get record to pass onto the event.
 334          $record = $DB->get_record('post', array('id' => $this->id));
 335          $DB->delete_records('post', array('id' => $this->id));
 336          core_tag_tag::remove_all_item_tags('core', 'post', $this->id);
 337  
 338          $event = \core\event\blog_entry_deleted::create(array(
 339              'objectid'      => $this->id,
 340              'relateduserid' => $this->userid
 341              ));
 342          $event->add_record_snapshot("post", $record);
 343          $event->set_blog_entry($this);
 344          $event->trigger();
 345      }
 346  
 347      /**
 348       * Function to add all context associations to an entry.
 349       *
 350       * @param string $unused This does nothing, do not use it.
 351       */
 352      public function add_associations($unused = null) {
 353  
 354          if ($unused !== null) {
 355              debugging('Illegal argument used in blog_entry->add_associations()', DEBUG_DEVELOPER);
 356          }
 357  
 358          $this->remove_associations();
 359  
 360          if (!empty($this->courseassoc)) {
 361              $this->add_association($this->courseassoc);
 362          }
 363  
 364          if (!empty($this->modassoc)) {
 365              $this->add_association($this->modassoc);
 366          }
 367      }
 368  
 369      /**
 370       * Add a single association for a blog entry
 371       *
 372       * @param int $contextid - id of context to associate with the blog entry.
 373       * @param string $unused This does nothing, do not use it.
 374       */
 375      public function add_association($contextid, $unused = null) {
 376          global $DB;
 377  
 378          if ($unused !== null) {
 379              debugging('Illegal argument used in blog_entry->add_association()', DEBUG_DEVELOPER);
 380          }
 381  
 382          $assocobject = new StdClass;
 383          $assocobject->contextid = $contextid;
 384          $assocobject->blogid = $this->id;
 385          $id = $DB->insert_record('blog_association', $assocobject);
 386  
 387          // Trigger an association created event.
 388          $context = context::instance_by_id($contextid);
 389          $eventparam = array(
 390              'objectid' => $id,
 391              'other' => array('associateid' => $context->instanceid, 'subject' => $this->subject, 'blogid' => $this->id),
 392              'relateduserid' => $this->userid
 393          );
 394          if ($context->contextlevel == CONTEXT_COURSE) {
 395              $eventparam['other']['associatetype'] = 'course';
 396  
 397          } else if ($context->contextlevel == CONTEXT_MODULE) {
 398              $eventparam['other']['associatetype'] = 'coursemodule';
 399          }
 400          $event = \core\event\blog_association_created::create($eventparam);
 401          $event->trigger();
 402      }
 403  
 404      /**
 405       * remove all associations for a blog entry
 406       *
 407       * @return void
 408       */
 409      public function remove_associations() {
 410          global $DB;
 411  
 412          $associations = $DB->get_records('blog_association', array('blogid' => $this->id));
 413          foreach ($associations as $association) {
 414  
 415              // Trigger an association deleted event.
 416              $context = context::instance_by_id($association->contextid);
 417              $eventparam = array(
 418                  'objectid' => $this->id,
 419                  'other' => array('subject' => $this->subject, 'blogid' => $this->id),
 420                  'relateduserid' => $this->userid
 421              );
 422              $event = \core\event\blog_association_deleted::create($eventparam);
 423              $event->add_record_snapshot('blog_association', $association);
 424              $event->trigger();
 425  
 426              // Now remove the association.
 427              $DB->delete_records('blog_association', array('id' => $association->id));
 428          }
 429      }
 430  
 431      /**
 432       * Deletes all the user files in the attachments area for an entry
 433       *
 434       * @return void
 435       */
 436      public function delete_attachments() {
 437          $fs = get_file_storage();
 438          $fs->delete_area_files(SYSCONTEXTID, 'blog', 'attachment', $this->id);
 439          $fs->delete_area_files(SYSCONTEXTID, 'blog', 'post', $this->id);
 440      }
 441  
 442      /**
 443       * User can edit a blog entry if this is their own blog entry and they have
 444       * the capability moodle/blog:create, or if they have the capability
 445       * moodle/blog:manageentries.
 446       * This also applies to deleting of entries.
 447       *
 448       * @param int $userid Optional. If not given, $USER is used
 449       * @return boolean
 450       */
 451      public function can_user_edit($userid=null) {
 452          global $CFG, $USER;
 453  
 454          if (empty($userid)) {
 455              $userid = $USER->id;
 456          }
 457  
 458          $sitecontext = context_system::instance();
 459  
 460          if (has_capability('moodle/blog:manageentries', $sitecontext)) {
 461              return true; // Can edit any blog entry.
 462          }
 463  
 464          if ($this->userid == $userid && has_capability('moodle/blog:create', $sitecontext)) {
 465              return true; // Can edit own when having blog:create capability.
 466          }
 467  
 468          return false;
 469      }
 470  
 471      /**
 472       * Checks to see if a user can view the blogs of another user.
 473       * Only blog level is checked here, the capabilities are enforced
 474       * in blog/index.php
 475       *
 476       * @param int $targetuserid ID of the user we are checking
 477       *
 478       * @return bool
 479       */
 480      public function can_user_view($targetuserid) {
 481          global $CFG, $USER, $DB;
 482          $sitecontext = context_system::instance();
 483  
 484          if (empty($CFG->enableblogs) || !has_capability('moodle/blog:view', $sitecontext)) {
 485              return false; // Blog system disabled or user has no blog view capability.
 486          }
 487  
 488          if (isloggedin() && $USER->id == $targetuserid) {
 489              return true; // Can view own entries in any case.
 490          }
 491  
 492          if (has_capability('moodle/blog:manageentries', $sitecontext)) {
 493              return true; // Can manage all entries.
 494          }
 495  
 496          // Coming for 1 entry, make sure it's not a draft.
 497          if ($this->publishstate == 'draft' && !has_capability('moodle/blog:viewdrafts', $sitecontext)) {
 498              return false;  // Can not view draft of others.
 499          }
 500  
 501          // Coming for 1 entry, make sure user is logged in, if not a public blog.
 502          if ($this->publishstate != 'public' && !isloggedin()) {
 503              return false;
 504          }
 505  
 506          switch ($CFG->bloglevel) {
 507              case BLOG_GLOBAL_LEVEL:
 508                  return true;
 509                  break;
 510  
 511              case BLOG_SITE_LEVEL:
 512                  if (isloggedin()) { // Not logged in viewers forbidden.
 513                      return true;
 514                  }
 515                  return false;
 516                  break;
 517  
 518              case BLOG_USER_LEVEL:
 519              default:
 520                  $personalcontext = context_user::instance($targetuserid);
 521                  return has_capability('moodle/user:readuserblogs', $personalcontext);
 522                  break;
 523          }
 524      }
 525  
 526      /**
 527       * Use this function to retrieve a list of publish states available for
 528       * the currently logged in user.
 529       *
 530       * @return array This function returns an array ideal for sending to moodles'
 531       *                choose_from_menu function.
 532       */
 533  
 534      public static function get_applicable_publish_states() {
 535          global $CFG;
 536          $options = array();
 537  
 538          // Everyone gets draft access.
 539          if ($CFG->bloglevel >= BLOG_USER_LEVEL) {
 540              $options['draft'] = get_string('publishtonoone', 'blog');
 541          }
 542  
 543          if ($CFG->bloglevel > BLOG_USER_LEVEL) {
 544              $options['site'] = get_string('publishtosite', 'blog');
 545          }
 546  
 547          if ($CFG->bloglevel >= BLOG_GLOBAL_LEVEL) {
 548              $options['public'] = get_string('publishtoworld', 'blog');
 549          }
 550  
 551          return $options;
 552      }
 553  }
 554  
 555  /**
 556   * Abstract Blog_Listing class: used to gather blog entries and output them as listings. One of the subclasses must be used.
 557   *
 558   * @package    moodlecore
 559   * @subpackage blog
 560   * @copyright  2009 Nicolas Connault
 561   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 562   */
 563  class blog_listing {
 564      /**
 565       * Array of blog_entry objects.
 566       * @var array $entries
 567       */
 568      public $entries = null;
 569  
 570      /**
 571       * Caches the total number of the entries.
 572       * @var int
 573       */
 574      public $totalentries = null;
 575  
 576      /**
 577       * An array of blog_filter_* objects
 578       * @var array $filters
 579       */
 580      public $filters = array();
 581  
 582      /**
 583       * Constructor
 584       *
 585       * @param array $filters An associative array of filtername => filterid
 586       */
 587      public function __construct($filters=array()) {
 588          // Unset filters overridden by more specific filters.
 589          foreach ($filters as $type => $id) {
 590              if (!empty($type) && !empty($id)) {
 591                  $this->filters[$type] = blog_filter::get_instance($id, $type);
 592              }
 593          }
 594  
 595          foreach ($this->filters as $type => $filter) {
 596              foreach ($filter->overrides as $override) {
 597                  if (array_key_exists($override, $this->filters)) {
 598                      unset($this->filters[$override]);
 599                  }
 600              }
 601          }
 602      }
 603  
 604      /**
 605       * Fetches the array of blog entries.
 606       *
 607       * @return array
 608       */
 609      public function get_entries($start=0, $limit=10) {
 610          global $DB;
 611  
 612          if ($this->entries === null) {
 613              if ($sqlarray = $this->get_entry_fetch_sql(false, 'created DESC')) {
 614                  $this->entries = $DB->get_records_sql($sqlarray['sql'], $sqlarray['params'], $start, $limit);
 615                  if (!$start && count($this->entries) < $limit) {
 616                      $this->totalentries = count($this->entries);
 617                  }
 618              } else {
 619                  return false;
 620              }
 621          }
 622  
 623          return $this->entries;
 624      }
 625  
 626      /**
 627       * Finds total number of blog entries
 628       *
 629       * @return int
 630       */
 631      public function count_entries() {
 632          global $DB;
 633          if ($this->totalentries === null) {
 634              if ($sqlarray = $this->get_entry_fetch_sql(true)) {
 635                  $this->totalentries = $DB->count_records_sql($sqlarray['sql'], $sqlarray['params']);
 636              } else {
 637                  $this->totalentries = 0;
 638              }
 639          }
 640          return $this->totalentries;
 641      }
 642  
 643      public function get_entry_fetch_sql($count=false, $sort='lastmodified DESC', $userid = false) {
 644          global $DB, $USER, $CFG;
 645  
 646          if (!$userid) {
 647              $userid = $USER->id;
 648          }
 649          $userfieldsapi = \core_user\fields::for_userpic();
 650          $allnamefields = $userfieldsapi->get_sql('u', false, '', 'useridalias', false)->selects;
 651          // The query used to locate blog entries is complicated.  It will be built from the following components:
 652          $requiredfields = "p.*, $allnamefields";  // The SELECT clause.
 653          $tables = array('p' => 'post', 'u' => 'user');   // Components of the FROM clause (table_id => table_name).
 654          // Components of the WHERE clause (conjunction).
 655          $conditions = array('u.deleted = 0', 'p.userid = u.id', '(p.module = \'blog\' OR p.module = \'blog_external\')');
 656  
 657          // Build up a clause for permission constraints.
 658  
 659          $params = array();
 660  
 661          // Fix for MDL-9165, use with readuserblogs capability in a user context can read that user's private blogs.
 662          // Admins can see all blogs regardless of publish states, as described on the help page.
 663          if (has_capability('moodle/user:readuserblogs', context_system::instance())) {
 664              // Don't add permission constraints.
 665  
 666          } else if (!empty($this->filters['user'])
 667                     && has_capability('moodle/user:readuserblogs',
 668                                       context_user::instance((empty($this->filters['user']->id) ? 0 : $this->filters['user']->id)))) {
 669              // Don't add permission constraints.
 670  
 671          } else {
 672              if (isloggedin() and !isguestuser()) {
 673                  // Dont check association records if there aren't any.
 674                  $assocexists = $DB->record_exists('blog_association', array());
 675  
 676                  // Begin permission sql clause.
 677                  $permissionsql = '(p.userid = ? ';
 678                  $params[] = $userid;
 679  
 680                  if ($CFG->bloglevel >= BLOG_SITE_LEVEL) { // Add permission to view site-level entries.
 681                      $permissionsql .= " OR p.publishstate = 'site' ";
 682                  }
 683  
 684                  if ($CFG->bloglevel >= BLOG_GLOBAL_LEVEL) { // Add permission to view global entries.
 685                      $permissionsql .= " OR p.publishstate = 'public' ";
 686                  }
 687  
 688                  $permissionsql .= ') ';   // Close permissions sql clause.
 689              } else {  // Default is access to public entries.
 690                  $permissionsql = "p.publishstate = 'public'";
 691              }
 692              $conditions[] = $permissionsql;  // Add permission constraints.
 693          }
 694  
 695          foreach ($this->filters as $type => $blogfilter) {
 696              $conditions = array_merge($conditions, $blogfilter->conditions);
 697              $params = array_merge($params, $blogfilter->params);
 698              $tables = array_merge($tables, $blogfilter->tables);
 699          }
 700  
 701          $tablessql = '';  // Build up the FROM clause.
 702          foreach ($tables as $tablename => $table) {
 703              $tablessql .= ($tablessql ? ', ' : '').'{'.$table.'} '.$tablename;
 704          }
 705  
 706          $sql = ($count) ? 'SELECT COUNT(*)' : 'SELECT ' . $requiredfields;
 707          $sql .= " FROM $tablessql WHERE " . implode(' AND ', $conditions);
 708          $sql .= ($count) ? '' : " ORDER BY $sort";
 709  
 710          return array('sql' => $sql, 'params' => $params);
 711      }
 712  
 713      /**
 714       * Outputs all the blog entries aggregated by this blog listing.
 715       *
 716       * @return void
 717       */
 718      public function print_entries() {
 719          global $CFG, $USER, $DB, $OUTPUT, $PAGE;
 720          $sitecontext = context_system::instance();
 721  
 722          // Blog renderer.
 723          $output = $PAGE->get_renderer('blog');
 724  
 725          $page  = optional_param('blogpage', 0, PARAM_INT);
 726          $limit = optional_param('limit', get_user_preferences('blogpagesize', 10), PARAM_INT);
 727          $start = $page * $limit;
 728  
 729          $morelink = '<br />&nbsp;&nbsp;';
 730  
 731          $entries = $this->get_entries($start, $limit);
 732          $totalentries = $this->count_entries();
 733          $pagingbar = new paging_bar($totalentries, $page, $limit, $this->get_baseurl());
 734          $pagingbar->pagevar = 'blogpage';
 735          $blogheaders = blog_get_headers();
 736  
 737          echo $OUTPUT->render($pagingbar);
 738  
 739          if (has_capability('moodle/blog:create', $sitecontext)) {
 740              // The user's blog is enabled and they are viewing their own blog.
 741              $userid = optional_param('userid', null, PARAM_INT);
 742  
 743              if (empty($userid) || (!empty($userid) && $userid == $USER->id)) {
 744  
 745                  $courseid = optional_param('courseid', null, PARAM_INT);
 746                  $modid = optional_param('modid', null, PARAM_INT);
 747  
 748                  $addurl = new moodle_url("$CFG->wwwroot/blog/edit.php");
 749                  $urlparams = array('action' => 'add',
 750                                     'userid' => $userid,
 751                                     'courseid' => $courseid,
 752                                     'groupid' => optional_param('groupid', null, PARAM_INT),
 753                                     'modid' => $modid,
 754                                     'tagid' => optional_param('tagid', null, PARAM_INT),
 755                                     'tag' => optional_param('tag', null, PARAM_INT),
 756                                     'search' => optional_param('search', null, PARAM_INT));
 757  
 758                  $urlparams = array_filter($urlparams);
 759                  $addurl->params($urlparams);
 760  
 761                  $addlink = '<div class="addbloglink">';
 762                  $addlink .= '<a href="'.$addurl->out().'">'. $blogheaders['stradd'].'</a>';
 763                  $addlink .= '</div>';
 764                  echo $addlink;
 765              }
 766          }
 767  
 768          if ($entries) {
 769              $count = 0;
 770              foreach ($entries as $entry) {
 771                  $blogentry = new blog_entry(null, $entry);
 772  
 773                  // Get the required blog entry data to render it.
 774                  $blogentry->prepare_render();
 775                  echo $output->render($blogentry);
 776  
 777                  $count++;
 778              }
 779  
 780              echo $OUTPUT->render($pagingbar);
 781  
 782              if (!$count) {
 783                  print '<br /><div style="text-align:center">'. get_string('noentriesyet', 'blog') .'</div><br />';
 784              }
 785  
 786              print $morelink.'<br />'."\n";
 787              return;
 788          }
 789      }
 790  
 791      // Find the base url from $_GET variables, for print_paging_bar.
 792      public function get_baseurl() {
 793          $getcopy  = $_GET;
 794  
 795          unset($getcopy['blogpage']);
 796  
 797          if (!empty($getcopy)) {
 798              $first = false;
 799              $querystring = '';
 800  
 801              foreach ($getcopy as $var => $val) {
 802                  if (!$first) {
 803                      $first = true;
 804                      $querystring .= "?$var=$val";
 805                  } else {
 806                      $querystring .= '&amp;'.$var.'='.$val;
 807                      $hasparam = true;
 808                  }
 809              }
 810          } else {
 811              $querystring = '?';
 812          }
 813  
 814          return strip_querystring(qualified_me()) . $querystring;
 815  
 816      }
 817  }
 818  
 819  /**
 820   * Abstract class for blog_filter objects.
 821   * A set of core filters are implemented here. To write new filters, you need to subclass
 822   * blog_filter and give it the name of the type you want (for example, blog_filter_entry).
 823   * The blog_filter abstract class will automatically use it when the filter is added to the
 824   * URL. The first parameter of the constructor is the ID of your filter, but it can be a string
 825   * or have any other meaning you wish it to have. The second parameter is called $type and is
 826   * used as a sub-type for filters that have a very similar implementation (see blog_filter_context for an example)
 827   */
 828  abstract class blog_filter {
 829      /**
 830       * An array of strings representing the available filter types for each blog_filter.
 831       * @var array $availabletypes
 832       */
 833      public $availabletypes = array();
 834  
 835      /**
 836       * The type of filter (for example, types of blog_filter_context are site, course and module)
 837       * @var string $type
 838       */
 839      public $type;
 840  
 841      /**
 842       * The unique ID for a filter's associated record
 843       * @var int $id
 844       */
 845      public $id;
 846  
 847      /**
 848       * An array of table aliases that are used in the WHERE conditions
 849       * @var array $tables
 850       */
 851      public $tables = array();
 852  
 853      /**
 854       * An array of WHERE conditions
 855       * @var array $conditions
 856       */
 857      public $conditions = array();
 858  
 859      /**
 860       * An array of SQL params
 861       * @var array $params
 862       */
 863      public $params = array();
 864  
 865      /**
 866       * An array of filter types which this particular filter type overrides: their conditions will not be evaluated
 867       */
 868      public $overrides = array();
 869  
 870      public function __construct($id, $type=null) {
 871          $this->id = $id;
 872          $this->type = $type;
 873      }
 874  
 875      /**
 876       * TODO This is poor design. A parent class should not know anything about its children.
 877       * The default case helps to resolve this design issue
 878       */
 879      public static function get_instance($id, $type) {
 880  
 881          switch ($type) {
 882              case 'site':
 883              case 'course':
 884              case 'module':
 885                  return new blog_filter_context($id, $type);
 886                  break;
 887  
 888              case 'group':
 889              case 'user':
 890                  return new blog_filter_user($id, $type);
 891                  break;
 892  
 893              case 'tag':
 894                  return new blog_filter_tag($id);
 895                  break;
 896  
 897              default:
 898                  $classname = "blog_filter_$type";
 899                  if (class_exists($classname)) {
 900                      return new $classname($id, $type);
 901                  }
 902          }
 903      }
 904  }
 905  
 906  /**
 907   * This filter defines the context level of the blog entries being searched: site, course, module
 908   */
 909  class blog_filter_context extends blog_filter {
 910      /**
 911       * Constructor
 912       *
 913       * @param string $type
 914       * @param int    $id
 915       */
 916      public function __construct($id=null, $type='site') {
 917          global $SITE, $CFG, $DB;
 918  
 919          if (empty($id)) {
 920              $this->type = 'site';
 921          } else {
 922              $this->id = $id;
 923              $this->type = $type;
 924          }
 925  
 926          $this->availabletypes = array('site' => get_string('site'),
 927                                        'course' => get_string('course'),
 928                                        'module' => get_string('activity'),
 929                                        'context' => get_string('coresystem'));
 930  
 931          switch ($this->type) {
 932              case 'course': // Careful of site course!
 933                  // Ignore course filter if blog associations are not enabled.
 934                  if ($this->id != $SITE->id && !empty($CFG->useblogassociations)) {
 935                      $this->overrides = array('site', 'context');
 936                      $context = context_course::instance($this->id);
 937                      $this->tables['ba'] = 'blog_association';
 938                      $this->conditions[] = 'p.id = ba.blogid';
 939                      $this->conditions[] = 'ba.contextid = '.$context->id;
 940                      break;
 941                  } else {
 942                      // We are dealing with the site course, do not break from the current case.
 943                  }
 944  
 945              case 'site':
 946                  // No special constraints.
 947                  break;
 948              case 'module':
 949                  if (!empty($CFG->useblogassociations)) {
 950                      $this->overrides = array('course', 'site', 'context');
 951  
 952                      $context = context_module::instance($this->id);
 953                      $this->tables['ba'] = 'blog_association';
 954                      $this->tables['p']  = 'post';
 955                      $this->conditions = array('p.id = ba.blogid', 'ba.contextid = ?');
 956                      $this->params = array($context->id);
 957                  }
 958                  break;
 959              case 'context':
 960                  if ($id != context_system::instance()->id && !empty($CFG->useblogassociations)) {
 961                      $this->overrides = array('site');
 962                      $context = context::instance_by_id($this->id);
 963                      $this->tables['ba'] = 'blog_association';
 964                      $this->tables['ctx'] = 'context';
 965                      $this->conditions[] = 'p.id = ba.blogid';
 966                      $this->conditions[] = 'ctx.id = ba.contextid';
 967                      $this->conditions[] = 'ctx.path LIKE ?';
 968                      $this->params = array($context->path . '%');
 969                  }
 970                  break;
 971  
 972          }
 973      }
 974  }
 975  
 976  /**
 977   * This filter defines the user level of the blog entries being searched: a userid or a groupid.
 978   * It can be combined with a context filter in order to refine the search.
 979   */
 980  class blog_filter_user extends blog_filter {
 981      public $tables = array('u' => 'user');
 982  
 983      /**
 984       * Constructor
 985       *
 986       * @param string $type
 987       * @param int    $id
 988       */
 989      public function __construct($id=null, $type='user') {
 990          global $CFG, $DB, $USER;
 991          $this->availabletypes = array('user' => get_string('user'), 'group' => get_string('group'));
 992  
 993          if (empty($id)) {
 994              $this->id = $USER->id;
 995              $this->type = 'user';
 996          } else {
 997              $this->id = $id;
 998              $this->type = $type;
 999          }
1000  
1001          if ($this->type == 'user') {
1002              $this->conditions = array('u.id = ?');
1003              $this->params = array($this->id);
1004              $this->overrides = array('group');
1005  
1006          } else if ($this->type == 'group') {
1007              $this->overrides = array('course', 'site');
1008  
1009              $this->tables['gm'] = 'groups_members';
1010              $this->conditions[] = 'p.userid = gm.userid';
1011              $this->conditions[] = 'gm.groupid = ?';
1012              $this->params[]     = $this->id;
1013  
1014              if (!empty($CFG->useblogassociations)) {  // Only show blog entries associated with this course.
1015                  $coursecontext     = context_course::instance($DB->get_field('groups', 'courseid', array('id' => $this->id)));
1016                  $this->tables['ba'] = 'blog_association';
1017                  $this->conditions[] = 'gm.groupid = ?';
1018                  $this->conditions[] = 'ba.contextid = ?';
1019                  $this->conditions[] = 'ba.blogid = p.id';
1020                  $this->params[]     = $this->id;
1021                  $this->params[]     = $coursecontext->id;
1022              }
1023          }
1024  
1025      }
1026  }
1027  
1028  /**
1029   * This filter defines a tag by which blog entries should be searched.
1030   */
1031  class blog_filter_tag extends blog_filter {
1032      public $tables = array('t' => 'tag', 'ti' => 'tag_instance', 'p' => 'post');
1033  
1034      /**
1035       * Constructor
1036       *
1037       * @return void
1038       */
1039      public function __construct($id) {
1040          global $DB;
1041          $this->id = $id;
1042  
1043          $this->conditions = array('ti.tagid = t.id',
1044                                    "ti.itemtype = 'post'",
1045                                    "ti.component = 'core'",
1046                                    'ti.itemid = p.id',
1047                                    't.id = ?');
1048          $this->params = array($this->id);
1049      }
1050  }
1051  
1052  /**
1053   * This filter defines a specific blog entry id.
1054   */
1055  class blog_filter_entry extends blog_filter {
1056      public $conditions = array('p.id = ?');
1057      public $overrides  = array('site', 'course', 'module', 'group', 'user', 'tag');
1058  
1059      public function __construct($id) {
1060          $this->id = $id;
1061          $this->params[] = $this->id;
1062      }
1063  }
1064  
1065  /**
1066   * This filter restricts the results to a time interval in seconds up to time()
1067   */
1068  class blog_filter_since extends blog_filter {
1069      public function __construct($interval) {
1070          $this->conditions[] = 'p.lastmodified >= ? AND p.lastmodified <= ?';
1071          $this->params[] = time() - $interval;
1072          $this->params[] = time();
1073      }
1074  }
1075  
1076  /**
1077   * Filter used to perform full-text search on an entry's subject, summary and content
1078   */
1079  class blog_filter_search extends blog_filter {
1080  
1081      public function __construct($searchterm) {
1082          global $DB;
1083          $this->conditions = array("(".$DB->sql_like('p.summary', '?', false)." OR
1084                                      ".$DB->sql_like('p.content', '?', false)." OR
1085                                      ".$DB->sql_like('p.subject', '?', false).")");
1086          $this->params[] = "%$searchterm%";
1087          $this->params[] = "%$searchterm%";
1088          $this->params[] = "%$searchterm%";
1089      }
1090  }
1091  
1092  
1093  /**
1094   * Renderable class to represent an entry attachment
1095   */
1096  class blog_entry_attachment implements renderable {
1097  
1098      public $filename;
1099      public $url;
1100      public $file;
1101  
1102      /**
1103       * Gets the file data
1104       *
1105       * @param stored_file $file
1106       * @param int $entryid Attachment entry id
1107       */
1108      public function __construct($file, $entryid) {
1109  
1110          global $CFG;
1111  
1112          $this->file = $file;
1113          $this->filename = $file->get_filename();
1114          $this->url = file_encode_url($CFG->wwwroot . '/pluginfile.php',
1115                                       '/' . SYSCONTEXTID . '/blog/attachment/' . $entryid . '/' . $this->filename);
1116      }
1117  
1118  }