blog/locallib.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  * 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         // Update tags.
 260         $this->add_tags_info();
 261
 262         if (!empty($CFG->useblogassociations)) {
 263             $this->add_associations();
 264         }
 265
 266         tag_set('post', $this->id, $this->tags, 'core', context_user::instance($this->userid)->id);
 267
 268         // Trigger an event for the new entry.
 269         $event = \core\event\blog_entry_created::create(array(
 270             'objectid'      => $this->id,
 271             'relateduserid' => $this->userid
 272         ));
 273         $event->set_blog_entry($this);
 274         $event->trigger();
 275     }
 276
 277     /**
 278      * Updates this entry in the database. Access control checks must be done by calling code.
 279      *
 280      * @param array       $params            Entry parameters.
 281      * @param moodleform  $form              Used for attachments.
 282      * @param array       $summaryoptions    Summary options.
 283      * @param array       $attachmentoptions Attachment options.
 284      *
 285      * @return void
 286      */
 287     public function edit($params=array(), $form=null, $summaryoptions=array(), $attachmentoptions=array()) {
 288         global $CFG, $DB;
 289
 290         $sitecontext = context_system::instance();
 291         $entry = $this;
 292
 293         $this->form = $form;
 294         foreach ($params as $var => $val) {
 295             $entry->$var = $val;
 296         }
 297
 298         $entry = file_postupdate_standard_editor($entry, 'summary', $summaryoptions, $sitecontext, 'blog', 'post', $entry->id);
 299         $entry = file_postupdate_standard_filemanager($entry,
 300                                                       'attachment',
 301                                                       $attachmentoptions,
 302                                                       $sitecontext,
 303                                                       'blog',
 304                                                       'attachment',
 305                                                       $entry->id);
 306
 307         if (!empty($CFG->useblogassociations)) {
 308             $entry->add_associations();
 309         }
 310
 311         $entry->lastmodified = time();
 312
 313         // Update record.
 314         $DB->update_record('post', $entry);
 315         tag_set('post', $entry->id, $entry->tags, 'core', context_user::instance($this->userid)->id);
 316
 317         $event = \core\event\blog_entry_updated::create(array(
 318             'objectid'      => $entry->id,
 319             'relateduserid' => $entry->userid
 320         ));
 321         $event->set_blog_entry($entry);
 322         $event->trigger();
 323     }
 324
 325     /**
 326      * Deletes this entry from the database. Access control checks must be done by calling code.
 327      *
 328      * @return void
 329      */
 330     public function delete() {
 331         global $DB;
 332
 333         $this->delete_attachments();
 334         $this->remove_associations();
 335
 336         // Get record to pass onto the event.
 337         $record = $DB->get_record('post', array('id' => $this->id));
 338         $DB->delete_records('post', array('id' => $this->id));
 339         tag_set('post', $this->id, array(), 'core', context_user::instance($this->userid)->id);
 340
 341         $event = \core\event\blog_entry_deleted::create(array(
 342             'objectid'      => $this->id,
 343             'relateduserid' => $this->userid
 344             ));
 345         $event->add_record_snapshot("post", $record);
 346         $event->set_blog_entry($this);
 347         $event->trigger();
 348     }
 349
 350     /**
 351      * Function to add all context associations to an entry.
 352      * TODO : Remove $action in 2.9 (MDL-41330)
 353      *
 354      * @param string $action - This does nothing, do not use it. This is present only for Backward compatibility.
 355      */
 356     public function add_associations($action = null) {
 357
 358         if (!empty($action)) {
 359             debugging('blog_entry->add_associations() does not accept any argument', DEBUG_DEVELOPER);
 360         }
 361
 362         $this->remove_associations();
 363
 364         if (!empty($this->courseassoc)) {
 365             $this->add_association($this->courseassoc);
 366         }
 367
 368         if (!empty($this->modassoc)) {
 369             $this->add_association($this->modassoc);
 370         }
 371     }
 372
 373     /**
 374      * Add a single association for a blog entry
 375      * TODO : Remove $action in 2.9 (MDL-41330)
 376      *
 377      * @param int $contextid - id of context to associate with the blog entry.
 378      * @param string $action - This does nothing, do not use it. This is present only for Backward compatibility.
 379      */
 380     public function add_association($contextid, $action = null) {
 381         global $DB;
 382
 383         if (!empty($action)) {
 384             debugging('blog_entry->add_association() accepts only one argument', DEBUG_DEVELOPER);
 385         }
 386
 387         $assocobject = new StdClass;
 388         $assocobject->contextid = $contextid;
 389         $assocobject->blogid = $this->id;
 390         $id = $DB->insert_record('blog_association', $assocobject);
 391
 392         // Trigger an association created event.
 393         $context = context::instance_by_id($contextid);
 394         $eventparam = array(
 395             'objectid' => $id,
 396             'other' => array('associateid' => $context->instanceid, 'subject' => $this->subject, 'blogid' => $this->id),
 397             'relateduserid' => $this->userid
 398         );
 399         if ($context->contextlevel == CONTEXT_COURSE) {
 400             $eventparam['other']['associatetype'] = 'course';
 401
 402         } else if ($context->contextlevel == CONTEXT_MODULE) {
 403             $eventparam['other']['associatetype'] = 'coursemodule';
 404         }
 405         $event = \core\event\blog_association_created::create($eventparam);
 406         $event->trigger();
 407     }
 408
 409     /**
 410      * remove all associations for a blog entry
 411      * @return voic
 412      */
 413     public function remove_associations() {
 414         global $DB;
 415         $DB->delete_records('blog_association', array('blogid' => $this->id));
 416     }
 417
 418     /**
 419      * Deletes all the user files in the attachments area for an entry
 420      *
 421      * @return void
 422      */
 423     public function delete_attachments() {
 424         $fs = get_file_storage();
 425         $fs->delete_area_files(SYSCONTEXTID, 'blog', 'attachment', $this->id);
 426         $fs->delete_area_files(SYSCONTEXTID, 'blog', 'post', $this->id);
 427     }
 428
 429     /**
 430      * function to attach tags into an entry
 431      * @return void
 432      */
 433     public function add_tags_info() {
 434
 435         $tags = array();
 436
 437         if ($otags = optional_param('otags', '', PARAM_INT)) {
 438             foreach ($otags as $tagid) {
 439                 // TODO : make this use the tag name in the form.
 440                 if ($tag = tag_get('id', $tagid)) {
 441                     $tags[] = $tag->name;
 442                 }
 443             }
 444         }
 445
 446         tag_set('post', $this->id, $tags, 'core', context_user::instance($this->userid)->id);
 447     }
 448
 449     /**
 450      * User can edit a blog entry if this is their own blog entry and they have
 451      * the capability moodle/blog:create, or if they have the capability
 452      * moodle/blog:manageentries.
 453      * This also applies to deleting of entries.
 454      *
 455      * @param int $userid Optional. If not given, $USER is used
 456      * @return boolean
 457      */
 458     public function can_user_edit($userid=null) {
 459         global $CFG, $USER;
 460
 461         if (empty($userid)) {
 462             $userid = $USER->id;
 463         }
 464
 465         $sitecontext = context_system::instance();
 466
 467         if (has_capability('moodle/blog:manageentries', $sitecontext)) {
 468             return true; // Can edit any blog entry.
 469         }
 470
 471         if ($this->userid == $userid && has_capability('moodle/blog:create', $sitecontext)) {
 472             return true; // Can edit own when having blog:create capability.
 473         }
 474
 475         return false;
 476     }
 477
 478     /**
 479      * Checks to see if a user can view the blogs of another user.
 480      * Only blog level is checked here, the capabilities are enforced
 481      * in blog/index.php
 482      *
 483      * @param int $targetuserid ID of the user we are checking
 484      *
 485      * @return bool
 486      */
 487     public function can_user_view($targetuserid) {
 488         global $CFG, $USER, $DB;
 489         $sitecontext = context_system::instance();
 490
 491         if (empty($CFG->enableblogs) || !has_capability('moodle/blog:view', $sitecontext)) {
 492             return false; // Blog system disabled or user has no blog view capability.
 493         }
 494
 495         if (isloggedin() && $USER->id == $targetuserid) {
 496             return true; // Can view own entries in any case.
 497         }
 498
 499         if (has_capability('moodle/blog:manageentries', $sitecontext)) {
 500             return true; // Can manage all entries.
 501         }
 502
 503         // Coming for 1 entry, make sure it's not a draft.
 504         if ($this->publishstate == 'draft' && !has_capability('moodle/blog:viewdrafts', $sitecontext)) {
 505             return false;  // Can not view draft of others.
 506         }
 507
 508         // Coming for 1 entry, make sure user is logged in, if not a public blog.
 509         if ($this->publishstate != 'public' && !isloggedin()) {
 510             return false;
 511         }
 512
 513         switch ($CFG->bloglevel) {
 514             case BLOG_GLOBAL_LEVEL:
 515                 return true;
 516                 break;
 517
 518             case BLOG_SITE_LEVEL:
 519                 if (isloggedin()) { // Not logged in viewers forbidden.
 520                     return true;
 521                 }
 522                 return false;
 523                 break;
 524
 525             case BLOG_USER_LEVEL:
 526             default:
 527                 $personalcontext = context_user::instance($targetuserid);
 528                 return has_capability('moodle/user:readuserblogs', $personalcontext);
 529                 break;
 530         }
 531     }
 532
 533     /**
 534      * Use this function to retrieve a list of publish states available for
 535      * the currently logged in user.
 536      *
 537      * @return array This function returns an array ideal for sending to moodles'
 538      *                choose_from_menu function.
 539      */
 540
 541     public static function get_applicable_publish_states() {
 542         global $CFG;
 543         $options = array();
 544
 545         // Everyone gets draft access.
 546         if ($CFG->bloglevel >= BLOG_USER_LEVEL) {
 547             $options['draft'] = get_string('publishtonoone', 'blog');
 548         }
 549
 550         if ($CFG->bloglevel > BLOG_USER_LEVEL) {
 551             $options['site'] = get_string('publishtosite', 'blog');
 552         }
 553
 554         if ($CFG->bloglevel >= BLOG_GLOBAL_LEVEL) {
 555             $options['public'] = get_string('publishtoworld', 'blog');
 556         }
 557
 558         return $options;
 559     }
 560 }
 561
 562 /**
 563  * Abstract Blog_Listing class: used to gather blog entries and output them as listings. One of the subclasses must be used.
 564  *
 565  * @package    moodlecore
 566  * @subpackage blog
 567  * @copyright  2009 Nicolas Connault
 568  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 569  */
 570 class blog_listing {
 571     /**
 572      * Array of blog_entry objects.
 573      * @var array $entries
 574      */
 575     public $entries = array();
 576
 577     /**
 578      * An array of blog_filter_* objects
 579      * @var array $filters
 580      */
 581     public $filters = array();
 582
 583     /**
 584      * Constructor
 585      *
 586      * @param array $filters An associative array of filtername => filterid
 587      */
 588     public function __construct($filters=array()) {
 589         // Unset filters overridden by more specific filters.
 590         foreach ($filters as $type => $id) {
 591             if (!empty($type) && !empty($id)) {
 592                 $this->filters[$type] = blog_filter::get_instance($id, $type);
 593             }
 594         }
 595
 596         foreach ($this->filters as $type => $filter) {
 597             foreach ($filter->overrides as $override) {
 598                 if (array_key_exists($override, $this->filters)) {
 599                     unset($this->filters[$override]);
 600                 }
 601             }
 602         }
 603     }
 604
 605     /**
 606      * Fetches the array of blog entries.
 607      *
 608      * @return array
 609      */
 610     public function get_entries($start=0, $limit=10) {
 611         global $DB;
 612
 613         if (empty($this->entries)) {
 614             if ($sqlarray = $this->get_entry_fetch_sql(false, 'created DESC')) {
 615                 $this->entries = $DB->get_records_sql($sqlarray['sql'], $sqlarray['params'], $start, $limit);
 616             } else {
 617                 return false;
 618             }
 619         }
 620
 621         return $this->entries;
 622     }
 623
 624     public function get_entry_fetch_sql($count=false, $sort='lastmodified DESC', $userid = false) {
 625         global $DB, $USER, $CFG;
 626
 627         if (!$userid) {
 628             $userid = $USER->id;
 629         }
 630
 631         $allnamefields = get_all_user_name_fields(true, 'u');
 632         // The query used to locate blog entries is complicated.  It will be built from the following components:
 633         $requiredfields = "p.*, $allnamefields, u.email";  // The SELECT clause.
 634         $tables = array('p' => 'post', 'u' => 'user');   // Components of the FROM clause (table_id => table_name).
 635         // Components of the WHERE clause (conjunction).
 636         $conditions = array('u.deleted = 0', 'p.userid = u.id', '(p.module = \'blog\' OR p.module = \'blog_external\')');
 637
 638         // Build up a clause for permission constraints.
 639
 640         $params = array();
 641
 642         // Fix for MDL-9165, use with readuserblogs capability in a user context can read that user's private blogs.
 643         // Admins can see all blogs regardless of publish states, as described on the help page.
 644         if (has_capability('moodle/user:readuserblogs', context_system::instance())) {
 645             // Don't add permission constraints.
 646
 647         } else if (!empty($this->filters['user'])
 648                    && has_capability('moodle/user:readuserblogs',
 649                                      context_user::instance((empty($this->filters['user']->id) ? 0 : $this->filters['user']->id)))) {
 650             // Don't add permission constraints.
 651
 652         } else {
 653             if (isloggedin() and !isguestuser()) {
 654                 // Dont check association records if there aren't any.
 655                 $assocexists = $DB->record_exists('blog_association', array());
 656
 657                 // Begin permission sql clause.
 658                 $permissionsql =  '(p.userid = ? ';
 659                 $params[] = $userid;
 660
 661                 if ($CFG->bloglevel >= BLOG_SITE_LEVEL) { // Add permission to view site-level entries.
 662                     $permissionsql .= " OR p.publishstate = 'site' ";
 663                 }
 664
 665                 if ($CFG->bloglevel >= BLOG_GLOBAL_LEVEL) { // Add permission to view global entries.
 666                     $permissionsql .= " OR p.publishstate = 'public' ";
 667                 }
 668
 669                 $permissionsql .= ') ';   // Close permissions sql clause.
 670             } else {  // Default is access to public entries.
 671                 $permissionsql = "p.publishstate = 'public'";
 672             }
 673             $conditions[] = $permissionsql;  // Add permission constraints.
 674         }
 675
 676         foreach ($this->filters as $type => $blogfilter) {
 677             $conditions = array_merge($conditions, $blogfilter->conditions);
 678             $params = array_merge($params, $blogfilter->params);
 679             $tables = array_merge($tables, $blogfilter->tables);
 680         }
 681
 682         $tablessql = '';  // Build up the FROM clause.
 683         foreach ($tables as $tablename => $table) {
 684             $tablessql .= ($tablessql ? ', ' : '').'{'.$table.'} '.$tablename;
 685         }
 686
 687         $sql = ($count) ? 'SELECT COUNT(*)' : 'SELECT ' . $requiredfields;
 688         $sql .= " FROM $tablessql WHERE " . implode(' AND ', $conditions);
 689         $sql .= ($count) ? '' : " ORDER BY $sort";
 690
 691         return array('sql' => $sql, 'params' => $params);
 692     }
 693
 694     /**
 695      * Outputs all the blog entries aggregated by this blog listing.
 696      *
 697      * @return void
 698      */
 699     public function print_entries() {
 700         global $CFG, $USER, $DB, $OUTPUT, $PAGE;
 701         $sitecontext = context_system::instance();
 702
 703         // Blog renderer.
 704         $output = $PAGE->get_renderer('blog');
 705
 706         $page  = optional_param('blogpage', 0, PARAM_INT);
 707         $limit = optional_param('limit', get_user_preferences('blogpagesize', 10), PARAM_INT);
 708         $start = $page * $limit;
 709
 710         $morelink = '<br />&nbsp;&nbsp;';
 711
 712         if ($sqlarray = $this->get_entry_fetch_sql(true)) {
 713             $totalentries = $DB->count_records_sql($sqlarray['sql'], $sqlarray['params']);
 714         } else {
 715             $totalentries = 0;
 716         }
 717
 718         $entries = $this->get_entries($start, $limit);
 719         $pagingbar = new paging_bar($totalentries, $page, $limit, $this->get_baseurl());
 720         $pagingbar->pagevar = 'blogpage';
 721         $blogheaders = blog_get_headers();
 722
 723         echo $OUTPUT->render($pagingbar);
 724
 725         if (has_capability('moodle/blog:create', $sitecontext)) {
 726             // The user's blog is enabled and they are viewing their own blog.
 727             $userid = optional_param('userid', null, PARAM_INT);
 728
 729             if (empty($userid) || (!empty($userid) && $userid == $USER->id)) {
 730
 731                 $courseid = optional_param('courseid', null, PARAM_INT);
 732                 $modid = optional_param('modid', null, PARAM_INT);
 733
 734                 $addurl = new moodle_url("$CFG->wwwroot/blog/edit.php");
 735                 $urlparams = array('action' => 'add',
 736                                    'userid' => $userid,
 737                                    'courseid' => $courseid,
 738                                    'groupid' => optional_param('groupid', null, PARAM_INT),
 739                                    'modid' => $modid,
 740                                    'tagid' => optional_param('tagid', null, PARAM_INT),
 741                                    'tag' => optional_param('tag', null, PARAM_INT),
 742                                    'search' => optional_param('search', null, PARAM_INT));
 743
 744                 $urlparams = array_filter($urlparams);
 745                 $addurl->params($urlparams);
 746
 747                 $addlink = '<div class="addbloglink">';
 748                 $addlink .= '<a href="'.$addurl->out().'">'. $blogheaders['stradd'].'</a>';
 749                 $addlink .= '</div>';
 750                 echo $addlink;
 751             }
 752         }
 753
 754         if ($entries) {
 755             $count = 0;
 756             foreach ($entries as $entry) {
 757                 $blogentry = new blog_entry(null, $entry);
 758
 759                 // Get the required blog entry data to render it.
 760                 $blogentry->prepare_render();
 761                 echo $output->render($blogentry);
 762
 763                 $count++;
 764             }
 765
 766             echo $OUTPUT->render($pagingbar);
 767
 768             if (!$count) {
 769                 print '<br /><div style="text-align:center">'. get_string('noentriesyet', 'blog') .'</div><br />';
 770             }
 771
 772             print $morelink.'<br />'."\n";
 773             return;
 774         }
 775     }
 776
 777     // Find the base url from $_GET variables, for print_paging_bar.
 778     public function get_baseurl() {
 779         $getcopy  = $_GET;
 780
 781         unset($getcopy['blogpage']);
 782
 783         if (!empty($getcopy)) {
 784             $first = false;
 785             $querystring = '';
 786
 787             foreach ($getcopy as $var => $val) {
 788                 if (!$first) {
 789                     $first = true;
 790                     $querystring .= "?$var=$val";
 791                 } else {
 792                     $querystring .= '&amp;'.$var.'='.$val;
 793                     $hasparam = true;
 794                 }
 795             }
 796         } else {
 797             $querystring = '?';
 798         }
 799
 800         return strip_querystring(qualified_me()) . $querystring;
 801
 802     }
 803 }
 804
 805 /**
 806  * Abstract class for blog_filter objects.
 807  * A set of core filters are implemented here. To write new filters, you need to subclass
 808  * blog_filter and give it the name of the type you want (for example, blog_filter_entry).
 809  * The blog_filter abstract class will automatically use it when the filter is added to the
 810  * URL. The first parameter of the constructor is the ID of your filter, but it can be a string
 811  * or have any other meaning you wish it to have. The second parameter is called $type and is
 812  * used as a sub-type for filters that have a very similar implementation (see blog_filter_context for an example)
 813  */
 814 abstract class blog_filter {
 815     /**
 816      * An array of strings representing the available filter types for each blog_filter.
 817      * @var array $availabletypes
 818      */
 819     public $availabletypes = array();
 820
 821     /**
 822      * The type of filter (for example, types of blog_filter_context are site, course and module)
 823      * @var string $type
 824      */
 825     public $type;
 826
 827     /**
 828      * The unique ID for a filter's associated record
 829      * @var int $id
 830      */
 831     public $id;
 832
 833     /**
 834      * An array of table aliases that are used in the WHERE conditions
 835      * @var array $tables
 836      */
 837     public $tables = array();
 838
 839     /**
 840      * An array of WHERE conditions
 841      * @var array $conditions
 842      */
 843     public $conditions = array();
 844
 845     /**
 846      * An array of SQL params
 847      * @var array $params
 848      */
 849     public $params = array();
 850
 851     /**
 852      * An array of filter types which this particular filter type overrides: their conditions will not be evaluated
 853      */
 854     public $overrides = array();
 855
 856     public function __construct($id, $type=null) {
 857         $this->id = $id;
 858         $this->type = $type;
 859     }
 860
 861     /**
 862      * TODO This is poor design. A parent class should not know anything about its children.
 863      * The default case helps to resolve this design issue
 864      */
 865     public static function get_instance($id, $type) {
 866
 867         switch ($type) {
 868             case 'site':
 869             case 'course':
 870             case 'module':
 871                 return new blog_filter_context($id, $type);
 872                 break;
 873
 874             case 'group':
 875             case 'user':
 876                 return new blog_filter_user($id, $type);
 877                 break;
 878
 879             case 'tag':
 880                 return new blog_filter_tag($id);
 881                 break;
 882
 883             default:
 884                 $classname = "blog_filter_$type";
 885                 if (class_exists($classname)) {
 886                     return new $classname($id, $type);
 887                 }
 888         }
 889     }
 890 }
 891
 892 /**
 893  * This filter defines the context level of the blog entries being searched: site, course, module
 894  */
 895 class blog_filter_context extends blog_filter {
 896     /**
 897      * Constructor
 898      *
 899      * @param string $type
 900      * @param int    $id
 901      */
 902     public function __construct($id=null, $type='site') {
 903         global $SITE, $CFG, $DB;
 904
 905         if (empty($id)) {
 906             $this->type = 'site';
 907         } else {
 908             $this->id = $id;
 909             $this->type = $type;
 910         }
 911
 912         $this->availabletypes = array('site' => get_string('site'),
 913                                       'course' => get_string('course'),
 914                                       'module' => get_string('activity'));
 915
 916         switch ($this->type) {
 917             case 'course': // Careful of site course!
 918                 // Ignore course filter if blog associations are not enabled.
 919                 if ($this->id != $SITE->id && !empty($CFG->useblogassociations)) {
 920                     $this->overrides = array('site');
 921                     $context = context_course::instance($this->id);
 922                     $this->tables['ba'] = 'blog_association';
 923                     $this->conditions[] = 'p.id = ba.blogid';
 924                     $this->conditions[] = 'ba.contextid = '.$context->id;
 925                     break;
 926                 } else {
 927                     // We are dealing with the site course, do not break from the current case.
 928                 }
 929
 930             case 'site':
 931                 // No special constraints.
 932                 break;
 933             case 'module':
 934                 if (!empty($CFG->useblogassociations)) {
 935                     $this->overrides = array('course', 'site');
 936
 937                     $context = context_module::instance($this->id);
 938                     $this->tables['ba'] = 'blog_association';
 939                     $this->tables['p']  = 'post';
 940                     $this->conditions = array('p.id = ba.blogid', 'ba.contextid = ?');
 941                     $this->params = array($context->id);
 942                 }
 943                 break;
 944         }
 945     }
 946 }
 947
 948 /**
 949  * This filter defines the user level of the blog entries being searched: a userid or a groupid.
 950  * It can be combined with a context filter in order to refine the search.
 951  */
 952 class blog_filter_user extends blog_filter {
 953     public $tables = array('u' => 'user');
 954
 955     /**
 956      * Constructor
 957      *
 958      * @param string $type
 959      * @param int    $id
 960      */
 961     public function __construct($id=null, $type='user') {
 962         global $CFG, $DB, $USER;
 963         $this->availabletypes = array('user' => get_string('user'), 'group' => get_string('group'));
 964
 965         if (empty($id)) {
 966             $this->id = $USER->id;
 967             $this->type = 'user';
 968         } else {
 969             $this->id = $id;
 970             $this->type = $type;
 971         }
 972
 973         if ($this->type == 'user') {
 974             $this->conditions = array('u.id = ?');
 975             $this->params = array($this->id);
 976             $this->overrides = array('group');
 977
 978         } else if ($this->type == 'group') {
 979             $this->overrides = array('course', 'site');
 980
 981             $this->tables['gm'] = 'groups_members';
 982             $this->conditions[] = 'p.userid = gm.userid';
 983             $this->conditions[] = 'gm.groupid = ?';
 984             $this->params[]     = $this->id;
 985
 986             if (!empty($CFG->useblogassociations)) {  // Only show blog entries associated with this course.
 987                 $coursecontext     = context_course::instance($DB->get_field('groups', 'courseid', array('id' => $this->id)));
 988                 $this->tables['ba'] = 'blog_association';
 989                 $this->conditions[] = 'gm.groupid = ?';
 990                 $this->conditions[] = 'ba.contextid = ?';
 991                 $this->conditions[] = 'ba.blogid = p.id';
 992                 $this->params[]     = $this->id;
 993                 $this->params[]     = $coursecontext->id;
 994             }
 995         }
 996
 997     }
 998 }
 999
1000 /**
1001  * This filter defines a tag by which blog entries should be searched.
1002  */
1003 class blog_filter_tag extends blog_filter {
1004     public $tables = array('t' => 'tag', 'ti' => 'tag_instance', 'p' => 'post');
1005
1006     /**
1007      * Constructor
1008      *
1009      * @return void
1010      */
1011     public function __construct($id) {
1012         global $DB;
1013         $this->id = $id;
1014
1015         $this->conditions = array('ti.tagid = t.id',
1016                                   "ti.itemtype = 'post'",
1017                                   'ti.itemid = p.id',
1018                                   't.id = ?');
1019         $this->params = array($this->id);
1020     }
1021 }
1022
1023 /**
1024  * This filter defines a specific blog entry id.
1025  */
1026 class blog_filter_entry extends blog_filter {
1027     public $conditions = array('p.id = ?');
1028     public $overrides  = array('site', 'course', 'module', 'group', 'user', 'tag');
1029
1030     public function __construct($id) {
1031         $this->id = $id;
1032         $this->params[] = $this->id;
1033     }
1034 }
1035
1036 /**
1037  * This filter restricts the results to a time interval in seconds up to time()
1038  */
1039 class blog_filter_since extends blog_filter {
1040     public function __construct($interval) {
1041         $this->conditions[] = 'p.lastmodified >= ? AND p.lastmodified <= ?';
1042         $this->params[] = time() - $interval;
1043         $this->params[] = time();
1044     }
1045 }
1046
1047 /**
1048  * Filter used to perform full-text search on an entry's subject, summary and content
1049  */
1050 class blog_filter_search extends blog_filter {
1051
1052     public function __construct($searchterm) {
1053         global $DB;
1054         $this->conditions = array("(".$DB->sql_like('p.summary', '?', false)." OR
1055                                     ".$DB->sql_like('p.content', '?', false)." OR
1056                                     ".$DB->sql_like('p.subject', '?', false).")");
1057         $this->params[] = "%$searchterm%";
1058         $this->params[] = "%$searchterm%";
1059         $this->params[] = "%$searchterm%";
1060     }
1061 }
1062
1063
1064 /**
1065  * Renderable class to represent an entry attachment
1066  */
1067 class blog_entry_attachment implements renderable {
1068
1069     public $filename;
1070     public $url;
1071     public $file;
1072
1073     /**
1074      * Gets the file data
1075      *
1076      * @param stored_file $file
1077      * @param int $entryid Attachment entry id
1078      */
1079     public function __construct($file, $entryid) {
1080
1081         global $CFG;
1082
1083         $this->file = $file;
1084         $this->filename = $file->get_filename();
1085         $this->url = file_encode_url($CFG->wwwroot . '/pluginfile.php',
1086                                      '/' . SYSCONTEXTID . '/blog/attachment/' . $entryid . '/' . $this->filename);
1087     }
1088
1089 }