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', $this);
 258
 259         if (!empty($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 }