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Differences Between: [Versions 310 and 311] [Versions 310 and 400] [Versions 310 and 401] [Versions 310 and 402] [Versions 310 and 403] [Versions 39 and 310]

   1  <?php
   2  
   3  // This file is part of Moodle - http://moodle.org/
   4  //
   5  // Moodle is free software: you can redistribute it and/or modify
   6  // it under the terms of the GNU General Public License as published by
   7  // the Free Software Foundation, either version 3 of the License, or
   8  // (at your option) any later version.
   9  //
  10  // Moodle is distributed in the hope that it will be useful,
  11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  // GNU General Public License for more details.
  14  //
  15  // You should have received a copy of the GNU General Public License
  16  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17  
  18  /**
  19   * Block Class and Functions
  20   *
  21   * This file defines the {@link block_manager} class,
  22   *
  23   * @package    core
  24   * @subpackage block
  25   * @copyright  1999 onwards Martin Dougiamas  http://dougiamas.com
  26   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  27   */
  28  
  29  defined('MOODLE_INTERNAL') || die();
  30  
  31  /**#@+
  32   * Default names for the block regions in the standard theme.
  33   */
  34  define('BLOCK_POS_LEFT',  'side-pre');
  35  define('BLOCK_POS_RIGHT', 'side-post');
  36  /**#@-*/
  37  
  38  define('BUI_CONTEXTS_FRONTPAGE_ONLY', 0);
  39  define('BUI_CONTEXTS_FRONTPAGE_SUBS', 1);
  40  define('BUI_CONTEXTS_ENTIRE_SITE', 2);
  41  
  42  define('BUI_CONTEXTS_CURRENT', 0);
  43  define('BUI_CONTEXTS_CURRENT_SUBS', 1);
  44  
  45  // Position of "Add block" control, to be used in theme config as a value for $THEME->addblockposition:
  46  // - default: as a fake block that is displayed in editing mode
  47  // - flatnav: "Add block" item in the flat navigation drawer in editing mode
  48  // - custom: none of the above, theme will take care of displaying the control.
  49  define('BLOCK_ADDBLOCK_POSITION_DEFAULT', 0);
  50  define('BLOCK_ADDBLOCK_POSITION_FLATNAV', 1);
  51  define('BLOCK_ADDBLOCK_POSITION_CUSTOM', -1);
  52  
  53  /**
  54   * Exception thrown when someone tried to do something with a block that does
  55   * not exist on a page.
  56   *
  57   * @copyright 2009 Tim Hunt
  58   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  59   * @since     Moodle 2.0
  60   */
  61  class block_not_on_page_exception extends moodle_exception {
  62      /**
  63       * Constructor
  64       * @param int $instanceid the block instance id of the block that was looked for.
  65       * @param object $page the current page.
  66       */
  67      public function __construct($instanceid, $page) {
  68          $a = new stdClass;
  69          $a->instanceid = $instanceid;
  70          $a->url = $page->url->out();
  71          parent::__construct('blockdoesnotexistonpage', '', $page->url->out(), $a);
  72      }
  73  }
  74  
  75  /**
  76   * This class keeps track of the block that should appear on a moodle_page.
  77   *
  78   * The page to work with as passed to the constructor.
  79   *
  80   * @copyright 2009 Tim Hunt
  81   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  82   * @since     Moodle 2.0
  83   */
  84  class block_manager {
  85      /**
  86       * The UI normally only shows block weights between -MAX_WEIGHT and MAX_WEIGHT,
  87       * although other weights are valid.
  88       */
  89      const MAX_WEIGHT = 10;
  90  
  91  /// Field declarations =========================================================
  92  
  93      /**
  94       * the moodle_page we are managing blocks for.
  95       * @var moodle_page
  96       */
  97      protected $page;
  98  
  99      /** @var array region name => 1.*/
 100      protected $regions = array();
 101  
 102      /** @var string the region where new blocks are added.*/
 103      protected $defaultregion = null;
 104  
 105      /** @var array will be $DB->get_records('blocks') */
 106      protected $allblocks = null;
 107  
 108      /**
 109       * @var array blocks that this user can add to this page. Will be a subset
 110       * of $allblocks, but with array keys block->name. Access this via the
 111       * {@link get_addable_blocks()} method to ensure it is lazy-loaded.
 112       */
 113      protected $addableblocks = null;
 114  
 115      /**
 116       * Will be an array region-name => array(db rows loaded in load_blocks);
 117       * @var array
 118       */
 119      protected $birecordsbyregion = null;
 120  
 121      /**
 122       * array region-name => array(block objects); populated as necessary by
 123       * the ensure_instances_exist method.
 124       * @var array
 125       */
 126      protected $blockinstances = array();
 127  
 128      /**
 129       * array region-name => array(block_contents objects) what actually needs to
 130       * be displayed in each region.
 131       * @var array
 132       */
 133      protected $visibleblockcontent = array();
 134  
 135      /**
 136       * array region-name => array(block_contents objects) extra block-like things
 137       * to be displayed in each region, before the real blocks.
 138       * @var array
 139       */
 140      protected $extracontent = array();
 141  
 142      /**
 143       * Used by the block move id, to track whether a block is currently being moved.
 144       *
 145       * When you click on the move icon of a block, first the page needs to reload with
 146       * extra UI for choosing a new position for a particular block. In that situation
 147       * this field holds the id of the block being moved.
 148       *
 149       * @var integer|null
 150       */
 151      protected $movingblock = null;
 152  
 153      /**
 154       * Show only fake blocks
 155       */
 156      protected $fakeblocksonly = false;
 157  
 158  /// Constructor ================================================================
 159  
 160      /**
 161       * Constructor.
 162       * @param object $page the moodle_page object object we are managing the blocks for,
 163       * or a reasonable faxilimily. (See the comment at the top of this class
 164       * and {@link http://en.wikipedia.org/wiki/Duck_typing})
 165       */
 166      public function __construct($page) {
 167          $this->page = $page;
 168      }
 169  
 170  /// Getter methods =============================================================
 171  
 172      /**
 173       * Get an array of all region names on this page where a block may appear
 174       *
 175       * @return array the internal names of the regions on this page where block may appear.
 176       */
 177      public function get_regions() {
 178          if (is_null($this->defaultregion)) {
 179              $this->page->initialise_theme_and_output();
 180          }
 181          return array_keys($this->regions);
 182      }
 183  
 184      /**
 185       * Get the region name of the region blocks are added to by default
 186       *
 187       * @return string the internal names of the region where new blocks are added
 188       * by default, and where any blocks from an unrecognised region are shown.
 189       * (Imagine that blocks were added with one theme selected, then you switched
 190       * to a theme with different block positions.)
 191       */
 192      public function get_default_region() {
 193          $this->page->initialise_theme_and_output();
 194          return $this->defaultregion;
 195      }
 196  
 197      /**
 198       * The list of block types that may be added to this page.
 199       *
 200       * @return array block name => record from block table.
 201       */
 202      public function get_addable_blocks() {
 203          $this->check_is_loaded();
 204  
 205          if (!is_null($this->addableblocks)) {
 206              return $this->addableblocks;
 207          }
 208  
 209          // Lazy load.
 210          $this->addableblocks = array();
 211  
 212          $allblocks = blocks_get_record();
 213          if (empty($allblocks)) {
 214              return $this->addableblocks;
 215          }
 216  
 217          $unaddableblocks = self::get_undeletable_block_types();
 218          $requiredbythemeblocks = $this->get_required_by_theme_block_types();
 219          $pageformat = $this->page->pagetype;
 220          foreach($allblocks as $block) {
 221              if (!$bi = block_instance($block->name)) {
 222                  continue;
 223              }
 224              if ($block->visible && !in_array($block->name, $unaddableblocks) &&
 225                      !in_array($block->name, $requiredbythemeblocks) &&
 226                      ($bi->instance_allow_multiple() || !$this->is_block_present($block->name)) &&
 227                      blocks_name_allowed_in_format($block->name, $pageformat) &&
 228                      $bi->user_can_addto($this->page)) {
 229                  $block->title = $bi->get_title();
 230                  $this->addableblocks[$block->name] = $block;
 231              }
 232          }
 233  
 234          core_collator::asort_objects_by_property($this->addableblocks, 'title');
 235          return $this->addableblocks;
 236      }
 237  
 238      /**
 239       * Given a block name, find out of any of them are currently present in the page
 240  
 241       * @param string $blockname - the basic name of a block (eg "navigation")
 242       * @return boolean - is there one of these blocks in the current page?
 243       */
 244      public function is_block_present($blockname) {
 245          if (empty($this->blockinstances)) {
 246              return false;
 247          }
 248  
 249          $requiredbythemeblocks = $this->get_required_by_theme_block_types();
 250          foreach ($this->blockinstances as $region) {
 251              foreach ($region as $instance) {
 252                  if (empty($instance->instance->blockname)) {
 253                      continue;
 254                  }
 255                  if ($instance->instance->blockname == $blockname) {
 256                      if ($instance->instance->requiredbytheme) {
 257                          if (!in_array($blockname, $requiredbythemeblocks)) {
 258                              continue;
 259                          }
 260                      }
 261                      return true;
 262                  }
 263              }
 264          }
 265          return false;
 266      }
 267  
 268      /**
 269       * Find out if a block type is known by the system
 270       *
 271       * @param string $blockname the name of the type of block.
 272       * @param boolean $includeinvisible if false (default) only check 'visible' blocks, that is, blocks enabled by the admin.
 273       * @return boolean true if this block in installed.
 274       */
 275      public function is_known_block_type($blockname, $includeinvisible = false) {
 276          $blocks = $this->get_installed_blocks();
 277          foreach ($blocks as $block) {
 278              if ($block->name == $blockname && ($includeinvisible || $block->visible)) {
 279                  return true;
 280              }
 281          }
 282          return false;
 283      }
 284  
 285      /**
 286       * Find out if a region exists on a page
 287       *
 288       * @param string $region a region name
 289       * @return boolean true if this region exists on this page.
 290       */
 291      public function is_known_region($region) {
 292          if (empty($region)) {
 293              return false;
 294          }
 295          return array_key_exists($region, $this->regions);
 296      }
 297  
 298      /**
 299       * Get an array of all blocks within a given region
 300       *
 301       * @param string $region a block region that exists on this page.
 302       * @return array of block instances.
 303       */
 304      public function get_blocks_for_region($region) {
 305          $this->check_is_loaded();
 306          $this->ensure_instances_exist($region);
 307          return $this->blockinstances[$region];
 308      }
 309  
 310      /**
 311       * Returns an array of block content objects that exist in a region
 312       *
 313       * @param string $region a block region that exists on this page.
 314       * @return array of block block_contents objects for all the blocks in a region.
 315       */
 316      public function get_content_for_region($region, $output) {
 317          $this->check_is_loaded();
 318          $this->ensure_content_created($region, $output);
 319          return $this->visibleblockcontent[$region];
 320      }
 321  
 322      /**
 323       * Returns an array of block content objects for all the existings regions
 324       *
 325       * @param renderer_base $output the rendered to use
 326       * @return array of block block_contents objects for all the blocks in all regions.
 327       * @since  Moodle 3.3
 328       */
 329      public function get_content_for_all_regions($output) {
 330          $contents = array();
 331          $this->check_is_loaded();
 332  
 333          foreach ($this->regions as $region => $val) {
 334              $this->ensure_content_created($region, $output);
 335              $contents[$region] = $this->visibleblockcontent[$region];
 336          }
 337          return $contents;
 338      }
 339  
 340      /**
 341       * Helper method used by get_content_for_region.
 342       * @param string $region region name
 343       * @param float $weight weight. May be fractional, since you may want to move a block
 344       * between ones with weight 2 and 3, say ($weight would be 2.5).
 345       * @return string URL for moving block $this->movingblock to this position.
 346       */
 347      protected function get_move_target_url($region, $weight) {
 348          return new moodle_url($this->page->url, array('bui_moveid' => $this->movingblock,
 349                  'bui_newregion' => $region, 'bui_newweight' => $weight, 'sesskey' => sesskey()));
 350      }
 351  
 352      /**
 353       * Determine whether a region contains anything. (Either any real blocks, or
 354       * the add new block UI.)
 355       *
 356       * (You may wonder why the $output parameter is required. Unfortunately,
 357       * because of the way that blocks work, the only reliable way to find out
 358       * if a block will be visible is to get the content for output, and to
 359       * get the content, you need a renderer. Fortunately, this is not a
 360       * performance problem, because we cache the output that is generated, and
 361       * in almost every case where we call region_has_content, we are about to
 362       * output the blocks anyway, so we are not doing wasted effort.)
 363       *
 364       * @param string $region a block region that exists on this page.
 365       * @param core_renderer $output a core_renderer. normally the global $OUTPUT.
 366       * @return boolean Whether there is anything in this region.
 367       */
 368      public function region_has_content($region, $output) {
 369  
 370          if (!$this->is_known_region($region)) {
 371              return false;
 372          }
 373          $this->check_is_loaded();
 374          $this->ensure_content_created($region, $output);
 375          // if ($this->page->user_is_editing() && $this->page->user_can_edit_blocks()) {
 376          // Mark Nielsen's patch - part 1
 377          if ($this->page->user_is_editing() && $this->page->user_can_edit_blocks() && $this->movingblock) {
 378              // If editing is on, we need all the block regions visible, for the
 379              // move blocks UI.
 380              return true;
 381          }
 382          return !empty($this->visibleblockcontent[$region]) || !empty($this->extracontent[$region]);
 383      }
 384  
 385      /**
 386       * Get an array of all of the installed blocks.
 387       *
 388       * @return array contents of the block table.
 389       */
 390      public function get_installed_blocks() {
 391          global $DB;
 392          if (is_null($this->allblocks)) {
 393              $this->allblocks = $DB->get_records('block');
 394          }
 395          return $this->allblocks;
 396      }
 397  
 398      /**
 399       * @return array names of block types that must exist on every page with this theme.
 400       */
 401      public function get_required_by_theme_block_types() {
 402          $requiredbythemeblocks = false;
 403          if (isset($this->page->theme->requiredblocks)) {
 404              $requiredbythemeblocks = $this->page->theme->requiredblocks;
 405          }
 406  
 407          if ($requiredbythemeblocks === false) {
 408              return array('navigation', 'settings');
 409          } else if ($requiredbythemeblocks === '') {
 410              return array();
 411          } else if (is_string($requiredbythemeblocks)) {
 412              return explode(',', $requiredbythemeblocks);
 413          } else {
 414              return $requiredbythemeblocks;
 415          }
 416      }
 417  
 418      /**
 419       * Make this block type undeletable and unaddable.
 420       *
 421       * @param mixed $blockidorname string or int
 422       */
 423      public static function protect_block($blockidorname) {
 424          global $DB;
 425  
 426          $syscontext = context_system::instance();
 427  
 428          require_capability('moodle/site:config', $syscontext);
 429  
 430          $block = false;
 431          if (is_int($blockidorname)) {
 432              $block = $DB->get_record('block', array('id' => $blockidorname), 'id, name', MUST_EXIST);
 433          } else {
 434              $block = $DB->get_record('block', array('name' => $blockidorname), 'id, name', MUST_EXIST);
 435          }
 436          $undeletableblocktypes = self::get_undeletable_block_types();
 437          if (!in_array($block->name, $undeletableblocktypes)) {
 438              $undeletableblocktypes[] = $block->name;
 439              set_config('undeletableblocktypes', implode(',', $undeletableblocktypes));
 440              add_to_config_log('block_protect', "0", "1", $block->name);
 441          }
 442      }
 443  
 444      /**
 445       * Make this block type deletable and addable.
 446       *
 447       * @param mixed $blockidorname string or int
 448       */
 449      public static function unprotect_block($blockidorname) {
 450          global $DB;
 451  
 452          $syscontext = context_system::instance();
 453  
 454          require_capability('moodle/site:config', $syscontext);
 455  
 456          $block = false;
 457          if (is_int($blockidorname)) {
 458              $block = $DB->get_record('block', array('id' => $blockidorname), 'id, name', MUST_EXIST);
 459          } else {
 460              $block = $DB->get_record('block', array('name' => $blockidorname), 'id, name', MUST_EXIST);
 461          }
 462          $undeletableblocktypes = self::get_undeletable_block_types();
 463          if (in_array($block->name, $undeletableblocktypes)) {
 464              $undeletableblocktypes = array_diff($undeletableblocktypes, array($block->name));
 465              set_config('undeletableblocktypes', implode(',', $undeletableblocktypes));
 466              add_to_config_log('block_protect', "1", "0", $block->name);
 467          }
 468  
 469      }
 470  
 471      /**
 472       * Get the list of "protected" blocks via admin block manager ui.
 473       *
 474       * @return array names of block types that cannot be added or deleted. E.g. array('navigation','settings').
 475       */
 476      public static function get_undeletable_block_types() {
 477          global $CFG;
 478          $undeletableblocks = false;
 479          if (isset($CFG->undeletableblocktypes)) {
 480              $undeletableblocks = $CFG->undeletableblocktypes;
 481          }
 482  
 483          if (empty($undeletableblocks)) {
 484              return array();
 485          } else if (is_string($undeletableblocks)) {
 486              return explode(',', $undeletableblocks);
 487          } else {
 488              return $undeletableblocks;
 489          }
 490      }
 491  
 492  /// Setter methods =============================================================
 493  
 494      /**
 495       * Add a region to a page
 496       *
 497       * @param string $region add a named region where blocks may appear on the current page.
 498       *      This is an internal name, like 'side-pre', not a string to display in the UI.
 499       * @param bool $custom True if this is a custom block region, being added by the page rather than the theme layout.
 500       */
 501      public function add_region($region, $custom = true) {
 502          global $SESSION;
 503          $this->check_not_yet_loaded();
 504          if ($custom) {
 505              if (array_key_exists($region, $this->regions)) {
 506                  // This here is EXACTLY why we should not be adding block regions into a page. It should
 507                  // ALWAYS be done in a theme layout.
 508                  debugging('A custom region conflicts with a block region in the theme.', DEBUG_DEVELOPER);
 509              }
 510              // We need to register this custom region against the page type being used.
 511              // This allows us to check, when performing block actions, that unrecognised regions can be worked with.
 512              $type = $this->page->pagetype;
 513              if (!isset($SESSION->custom_block_regions)) {
 514                  $SESSION->custom_block_regions = array($type => array($region));
 515              } else if (!isset($SESSION->custom_block_regions[$type])) {
 516                  $SESSION->custom_block_regions[$type] = array($region);
 517              } else if (!in_array($region, $SESSION->custom_block_regions[$type])) {
 518                  $SESSION->custom_block_regions[$type][] = $region;
 519              }
 520          }
 521          $this->regions[$region] = 1;
 522  
 523          // Checking the actual property instead of calling get_default_region as it ends up in a recursive call.
 524          if (empty($this->defaultregion)) {
 525              $this->set_default_region($region);
 526          }
 527      }
 528  
 529      /**
 530       * Add an array of regions
 531       * @see add_region()
 532       *
 533       * @param array $regions this utility method calls add_region for each array element.
 534       */
 535      public function add_regions($regions, $custom = true) {
 536          foreach ($regions as $region) {
 537              $this->add_region($region, $custom);
 538          }
 539      }
 540  
 541      /**
 542       * Finds custom block regions associated with a page type and registers them with this block manager.
 543       *
 544       * @param string $pagetype
 545       */
 546      public function add_custom_regions_for_pagetype($pagetype) {
 547          global $SESSION;
 548          if (isset($SESSION->custom_block_regions[$pagetype])) {
 549              foreach ($SESSION->custom_block_regions[$pagetype] as $customregion) {
 550                  $this->add_region($customregion, false);
 551              }
 552          }
 553      }
 554  
 555      /**
 556       * Set the default region for new blocks on the page
 557       *
 558       * @param string $defaultregion the internal names of the region where new
 559       * blocks should be added by default, and where any blocks from an
 560       * unrecognised region are shown.
 561       */
 562      public function set_default_region($defaultregion) {
 563          $this->check_not_yet_loaded();
 564          if ($defaultregion) {
 565              $this->check_region_is_known($defaultregion);
 566          }
 567          $this->defaultregion = $defaultregion;
 568      }
 569  
 570      /**
 571       * Add something that looks like a block, but which isn't an actual block_instance,
 572       * to this page.
 573       *
 574       * @param block_contents $bc the content of the block-like thing.
 575       * @param string $region a block region that exists on this page.
 576       */
 577      public function add_fake_block($bc, $region) {
 578          $this->page->initialise_theme_and_output();
 579          if (!$this->is_known_region($region)) {
 580              $region = $this->get_default_region();
 581          }
 582          if (array_key_exists($region, $this->visibleblockcontent)) {
 583              throw new coding_exception('block_manager has already prepared the blocks in region ' .
 584                      $region . 'for output. It is too late to add a fake block.');
 585          }
 586          if (!isset($bc->attributes['data-block'])) {
 587              $bc->attributes['data-block'] = '_fake';
 588          }
 589          $bc->attributes['class'] .= ' block_fake';
 590          $this->extracontent[$region][] = $bc;
 591      }
 592  
 593      /**
 594       * Checks to see whether all of the blocks within the given region are docked
 595       *
 596       * @see region_uses_dock
 597       * @param string $region
 598       * @return bool True if all of the blocks within that region are docked
 599       *
 600       * Return false as from MDL-64506
 601       */
 602      public function region_completely_docked($region, $output) {
 603          return false;
 604      }
 605  
 606      /**
 607       * Checks to see whether any of the blocks within the given regions are docked
 608       *
 609       * @see region_completely_docked
 610       * @param array|string $regions array of regions (or single region)
 611       * @return bool True if any of the blocks within that region are docked
 612       *
 613       * Return false as from MDL-64506
 614       */
 615      public function region_uses_dock($regions, $output) {
 616          return false;
 617      }
 618  
 619  /// Actions ====================================================================
 620  
 621      /**
 622       * This method actually loads the blocks for our page from the database.
 623       *
 624       * @param boolean|null $includeinvisible
 625       *      null (default) - load hidden blocks if $this->page->user_is_editing();
 626       *      true - load hidden blocks.
 627       *      false - don't load hidden blocks.
 628       */
 629      public function load_blocks($includeinvisible = null) {
 630          global $DB, $CFG;
 631  
 632          if (!is_null($this->birecordsbyregion)) {
 633              // Already done.
 634              return;
 635          }
 636  
 637          if ($CFG->version < 2009050619) {
 638              // Upgrade/install not complete. Don't try too show any blocks.
 639              $this->birecordsbyregion = array();
 640              return;
 641          }
 642  
 643          // Ensure we have been initialised.
 644          if (is_null($this->defaultregion)) {
 645              $this->page->initialise_theme_and_output();
 646              // If there are still no block regions, then there are no blocks on this page.
 647              if (empty($this->regions)) {
 648                  $this->birecordsbyregion = array();
 649                  return;
 650              }
 651          }
 652  
 653          // Check if we need to load normal blocks
 654          if ($this->fakeblocksonly) {
 655              $this->birecordsbyregion = $this->prepare_per_region_arrays();
 656              return;
 657          }
 658  
 659          // Exclude auto created blocks if they are not undeletable in this theme.
 660          $requiredbytheme = $this->get_required_by_theme_block_types();
 661          $requiredbythemecheck = '';
 662          $requiredbythemeparams = array();
 663          $requiredbythemenotparams = array();
 664          if (!empty($requiredbytheme)) {
 665              list($testsql, $requiredbythemeparams) = $DB->get_in_or_equal($requiredbytheme, SQL_PARAMS_NAMED, 'requiredbytheme');
 666              list($testnotsql, $requiredbythemenotparams) = $DB->get_in_or_equal($requiredbytheme, SQL_PARAMS_NAMED,
 667                                                                                  'notrequiredbytheme', false);
 668              $requiredbythemecheck = 'AND ((bi.blockname ' . $testsql . ' AND bi.requiredbytheme = 1) OR ' .
 669                                  ' (bi.blockname ' . $testnotsql . ' AND bi.requiredbytheme = 0))';
 670          } else {
 671              $requiredbythemecheck = 'AND (bi.requiredbytheme = 0)';
 672          }
 673  
 674          if (is_null($includeinvisible)) {
 675              $includeinvisible = $this->page->user_is_editing();
 676          }
 677          if ($includeinvisible) {
 678              $visiblecheck = '';
 679          } else {
 680              $visiblecheck = 'AND (bp.visible = 1 OR bp.visible IS NULL) AND (bs.visible = 1 OR bs.visible IS NULL)';
 681          }
 682  
 683          $context = $this->page->context;
 684          $contexttest = 'bi.parentcontextid IN (:contextid2, :contextid3)';
 685          $parentcontextparams = array();
 686          $parentcontextids = $context->get_parent_context_ids();
 687          if ($parentcontextids) {
 688              list($parentcontexttest, $parentcontextparams) =
 689                      $DB->get_in_or_equal($parentcontextids, SQL_PARAMS_NAMED, 'parentcontext');
 690              $contexttest = "($contexttest OR (bi.showinsubcontexts = 1 AND bi.parentcontextid $parentcontexttest))";
 691          }
 692  
 693          $pagetypepatterns = matching_page_type_patterns($this->page->pagetype);
 694          list($pagetypepatterntest, $pagetypepatternparams) =
 695                  $DB->get_in_or_equal($pagetypepatterns, SQL_PARAMS_NAMED, 'pagetypepatterntest');
 696  
 697          $ccselect = ', ' . context_helper::get_preload_record_columns_sql('ctx');
 698          $ccjoin = "LEFT JOIN {context} ctx ON (ctx.instanceid = bi.id AND ctx.contextlevel = :contextlevel)";
 699  
 700          $systemcontext = context_system::instance();
 701          $params = array(
 702              'contextlevel' => CONTEXT_BLOCK,
 703              'subpage1' => $this->page->subpage,
 704              'subpage2' => $this->page->subpage,
 705              'subpage3' => $this->page->subpage,
 706              'contextid1' => $context->id,
 707              'contextid2' => $context->id,
 708              'contextid3' => $systemcontext->id,
 709              'contextid4' => $systemcontext->id,
 710              'pagetype' => $this->page->pagetype,
 711              'pagetype2' => $this->page->pagetype,
 712          );
 713          if ($this->page->subpage === '') {
 714              $params['subpage1'] = '';
 715              $params['subpage2'] = '';
 716              $params['subpage3'] = '';
 717          }
 718          $sql = "SELECT
 719                      bi.id,
 720                      COALESCE(bp.id, bs.id) AS blockpositionid,
 721                      bi.blockname,
 722                      bi.parentcontextid,
 723                      bi.showinsubcontexts,
 724                      bi.pagetypepattern,
 725                      bi.requiredbytheme,
 726                      bi.subpagepattern,
 727                      bi.defaultregion,
 728                      bi.defaultweight,
 729                      COALESCE(bp.visible, bs.visible, 1) AS visible,
 730                      COALESCE(bp.region, bs.region, bi.defaultregion) AS region,
 731                      COALESCE(bp.weight, bs.weight, bi.defaultweight) AS weight,
 732                      bi.configdata
 733                      $ccselect
 734  
 735                  FROM {block_instances} bi
 736                  JOIN {block} b ON bi.blockname = b.name
 737                  LEFT JOIN {block_positions} bp ON bp.blockinstanceid = bi.id
 738                                                    AND bp.contextid = :contextid1
 739                                                    AND bp.pagetype = :pagetype
 740                                                    AND bp.subpage = :subpage1
 741                  LEFT JOIN {block_positions} bs ON bs.blockinstanceid = bi.id
 742                                                    AND bs.contextid = :contextid4
 743                                                    AND bs.pagetype = :pagetype2
 744                                                    AND bs.subpage = :subpage3
 745                  $ccjoin
 746  
 747                  WHERE
 748                  $contexttest
 749                  AND bi.pagetypepattern $pagetypepatterntest
 750                  AND (bi.subpagepattern IS NULL OR bi.subpagepattern = :subpage2)
 751                  $visiblecheck
 752                  AND b.visible = 1
 753                  $requiredbythemecheck
 754  
 755                  ORDER BY
 756                      COALESCE(bp.region, bs.region, bi.defaultregion),
 757                      COALESCE(bp.weight, bs.weight, bi.defaultweight),
 758                      bi.id";
 759  
 760          $allparams = $params + $parentcontextparams + $pagetypepatternparams + $requiredbythemeparams + $requiredbythemenotparams;
 761          $blockinstances = $DB->get_recordset_sql($sql, $allparams);
 762  
 763          $this->birecordsbyregion = $this->prepare_per_region_arrays();
 764          $unknown = array();
 765          foreach ($blockinstances as $bi) {
 766              context_helper::preload_from_record($bi);
 767              if ($this->is_known_region($bi->region)) {
 768                  $this->birecordsbyregion[$bi->region][] = $bi;
 769              } else {
 770                  $unknown[] = $bi;
 771              }
 772          }
 773          $blockinstances->close();
 774  
 775          // Pages don't necessarily have a defaultregion. The  one time this can
 776          // happen is when there are no theme block regions, but the script itself
 777          // has a block region in the main content area.
 778          if (!empty($this->defaultregion)) {
 779              $this->birecordsbyregion[$this->defaultregion] =
 780                      array_merge($this->birecordsbyregion[$this->defaultregion], $unknown);
 781          }
 782      }
 783  
 784      /**
 785       * Add a block to the current page, or related pages. The block is added to
 786       * context $this->page->contextid. If $pagetypepattern $subpagepattern
 787       *
 788       * @param string $blockname The type of block to add.
 789       * @param string $region the block region on this page to add the block to.
 790       * @param integer $weight determines the order where this block appears in the region.
 791       * @param boolean $showinsubcontexts whether this block appears in subcontexts, or just the current context.
 792       * @param string|null $pagetypepattern which page types this block should appear on. Defaults to just the current page type.
 793       * @param string|null $subpagepattern which subpage this block should appear on. NULL = any (the default), otherwise only the specified subpage.
 794       */
 795      public function add_block($blockname, $region, $weight, $showinsubcontexts, $pagetypepattern = NULL, $subpagepattern = NULL) {
 796          global $DB;
 797          // Allow invisible blocks because this is used when adding default page blocks, which
 798          // might include invisible ones if the user makes some default blocks invisible
 799          $this->check_known_block_type($blockname, true);
 800          $this->check_region_is_known($region);
 801  
 802          if (empty($pagetypepattern)) {
 803              $pagetypepattern = $this->page->pagetype;
 804          }
 805  
 806          $blockinstance = new stdClass;
 807          $blockinstance->blockname = $blockname;
 808          $blockinstance->parentcontextid = $this->page->context->id;
 809          $blockinstance->showinsubcontexts = !empty($showinsubcontexts);
 810          $blockinstance->pagetypepattern = $pagetypepattern;
 811          $blockinstance->subpagepattern = $subpagepattern;
 812          $blockinstance->defaultregion = $region;
 813          $blockinstance->defaultweight = $weight;
 814          $blockinstance->configdata = '';
 815          $blockinstance->timecreated = time();
 816          $blockinstance->timemodified = $blockinstance->timecreated;
 817          $blockinstance->id = $DB->insert_record('block_instances', $blockinstance);
 818  
 819          // Ensure the block context is created.
 820          context_block::instance($blockinstance->id);
 821  
 822          // If the new instance was created, allow it to do additional setup
 823          if ($block = block_instance($blockname, $blockinstance)) {
 824              $block->instance_create();
 825          }
 826      }
 827  
 828      public function add_block_at_end_of_default_region($blockname) {
 829          if (empty($this->birecordsbyregion)) {
 830              // No blocks or block regions exist yet.
 831              return;
 832          }
 833          $defaulregion = $this->get_default_region();
 834  
 835          $lastcurrentblock = end($this->birecordsbyregion[$defaulregion]);
 836          if ($lastcurrentblock) {
 837              $weight = $lastcurrentblock->weight + 1;
 838          } else {
 839              $weight = 0;
 840          }
 841  
 842          if ($this->page->subpage) {
 843              $subpage = $this->page->subpage;
 844          } else {
 845              $subpage = null;
 846          }
 847  
 848          // Special case. Course view page type include the course format, but we
 849          // want to add the block non-format-specifically.
 850          $pagetypepattern = $this->page->pagetype;
 851          if (strpos($pagetypepattern, 'course-view') === 0) {
 852              $pagetypepattern = 'course-view-*';
 853          }
 854  
 855          // We should end using this for ALL the blocks, making always the 1st option
 856          // the default one to be used. Until then, this is one hack to avoid the
 857          // 'pagetypewarning' message on blocks initial edition (MDL-27829) caused by
 858          // non-existing $pagetypepattern set. This way at least we guarantee one "valid"
 859          // (the FIRST $pagetypepattern will be set)
 860  
 861          // We are applying it to all blocks created in mod pages for now and only if the
 862          // default pagetype is not one of the available options
 863          if (preg_match('/^mod-.*-/', $pagetypepattern)) {
 864              $pagetypelist = generate_page_type_patterns($this->page->pagetype, null, $this->page->context);
 865              // Only go for the first if the pagetype is not a valid option
 866              if (is_array($pagetypelist) && !array_key_exists($pagetypepattern, $pagetypelist)) {
 867                  $pagetypepattern = key($pagetypelist);
 868              }
 869          }
 870          // Surely other pages like course-report will need this too, they just are not important
 871          // enough now. This will be decided in the coming days. (MDL-27829, MDL-28150)
 872  
 873          $this->add_block($blockname, $defaulregion, $weight, false, $pagetypepattern, $subpage);
 874      }
 875  
 876      /**
 877       * Convenience method, calls add_block repeatedly for all the blocks in $blocks. Optionally, a starting weight
 878       * can be used to decide the starting point that blocks are added in the region, the weight is passed to {@link add_block}
 879       * and incremented by the position of the block in the $blocks array
 880       *
 881       * @param array $blocks array with array keys the region names, and values an array of block names.
 882       * @param string $pagetypepattern optional. Passed to {@link add_block()}
 883       * @param string $subpagepattern optional. Passed to {@link add_block()}
 884       * @param boolean $showinsubcontexts optional. Passed to {@link add_block()}
 885       * @param integer $weight optional. Determines the starting point that the blocks are added in the region.
 886       */
 887      public function add_blocks($blocks, $pagetypepattern = NULL, $subpagepattern = NULL, $showinsubcontexts=false, $weight=0) {
 888          $initialweight = $weight;
 889          $this->add_regions(array_keys($blocks), false);
 890          foreach ($blocks as $region => $regionblocks) {
 891              foreach ($regionblocks as $offset => $blockname) {
 892                  $weight = $initialweight + $offset;
 893                  $this->add_block($blockname, $region, $weight, $showinsubcontexts, $pagetypepattern, $subpagepattern);
 894              }
 895          }
 896      }
 897  
 898      /**
 899       * Move a block to a new position on this page.
 900       *
 901       * If this block cannot appear on any other pages, then we change defaultposition/weight
 902       * in the block_instances table. Otherwise we just set the position on this page.
 903       *
 904       * @param $blockinstanceid the block instance id.
 905       * @param $newregion the new region name.
 906       * @param $newweight the new weight.
 907       */
 908      public function reposition_block($blockinstanceid, $newregion, $newweight) {
 909          global $DB;
 910  
 911          $this->check_region_is_known($newregion);
 912          $inst = $this->find_instance($blockinstanceid);
 913  
 914          $bi = $inst->instance;
 915          if ($bi->weight == $bi->defaultweight && $bi->region == $bi->defaultregion &&
 916                  !$bi->showinsubcontexts && strpos($bi->pagetypepattern, '*') === false &&
 917                  (!$this->page->subpage || $bi->subpagepattern)) {
 918  
 919              // Set default position
 920              $newbi = new stdClass;
 921              $newbi->id = $bi->id;
 922              $newbi->defaultregion = $newregion;
 923              $newbi->defaultweight = $newweight;
 924              $newbi->timemodified = time();
 925              $DB->update_record('block_instances', $newbi);
 926  
 927              if ($bi->blockpositionid) {
 928                  $bp = new stdClass;
 929                  $bp->id = $bi->blockpositionid;
 930                  $bp->region = $newregion;
 931                  $bp->weight = $newweight;
 932                  $DB->update_record('block_positions', $bp);
 933              }
 934  
 935          } else {
 936              // Just set position on this page.
 937              $bp = new stdClass;
 938              $bp->region = $newregion;
 939              $bp->weight = $newweight;
 940  
 941              if ($bi->blockpositionid) {
 942                  $bp->id = $bi->blockpositionid;
 943                  $DB->update_record('block_positions', $bp);
 944  
 945              } else {
 946                  $bp->blockinstanceid = $bi->id;
 947                  $bp->contextid = $this->page->context->id;
 948                  $bp->pagetype = $this->page->pagetype;
 949                  if ($this->page->subpage) {
 950                      $bp->subpage = $this->page->subpage;
 951                  } else {
 952                      $bp->subpage = '';
 953                  }
 954                  $bp->visible = $bi->visible;
 955                  $DB->insert_record('block_positions', $bp);
 956              }
 957          }
 958      }
 959  
 960      /**
 961       * Find a given block by its instance id
 962       *
 963       * @param integer $instanceid
 964       * @return block_base
 965       */
 966      public function find_instance($instanceid) {
 967          foreach ($this->regions as $region => $notused) {
 968              $this->ensure_instances_exist($region);
 969              foreach($this->blockinstances[$region] as $instance) {
 970                  if ($instance->instance->id == $instanceid) {
 971                      return $instance;
 972                  }
 973              }
 974          }
 975          throw new block_not_on_page_exception($instanceid, $this->page);
 976      }
 977  
 978  /// Inner workings =============================================================
 979  
 980      /**
 981       * Check whether the page blocks have been loaded yet
 982       *
 983       * @return void Throws coding exception if already loaded
 984       */
 985      protected function check_not_yet_loaded() {
 986          if (!is_null($this->birecordsbyregion)) {
 987              throw new coding_exception('block_manager has already loaded the blocks, to it is too late to change things that might affect which blocks are visible.');
 988          }
 989      }
 990  
 991      /**
 992       * Check whether the page blocks have been loaded yet
 993       *
 994       * Nearly identical to the above function {@link check_not_yet_loaded()} except different message
 995       *
 996       * @return void Throws coding exception if already loaded
 997       */
 998      protected function check_is_loaded() {
 999          if (is_null($this->birecordsbyregion)) {
1000              throw new coding_exception('block_manager has not yet loaded the blocks, to it is too soon to request the information you asked for.');
1001          }
1002      }
1003  
1004      /**
1005       * Check if a block type is known and usable
1006       *
1007       * @param string $blockname The block type name to search for
1008       * @param bool $includeinvisible Include disabled block types in the initial pass
1009       * @return void Coding Exception thrown if unknown or not enabled
1010       */
1011      protected function check_known_block_type($blockname, $includeinvisible = false) {
1012          if (!$this->is_known_block_type($blockname, $includeinvisible)) {
1013              if ($this->is_known_block_type($blockname, true)) {
1014                  throw new coding_exception('Unknown block type ' . $blockname);
1015              } else {
1016                  throw new coding_exception('Block type ' . $blockname . ' has been disabled by the administrator.');
1017              }
1018          }
1019      }
1020  
1021      /**
1022       * Check if a region is known by its name
1023       *
1024       * @param string $region
1025       * @return void Coding Exception thrown if the region is not known
1026       */
1027      protected function check_region_is_known($region) {
1028          if (!$this->is_known_region($region)) {
1029              throw new coding_exception('Trying to reference an unknown block region ' . $region);
1030          }
1031      }
1032  
1033      /**
1034       * Returns an array of region names as keys and nested arrays for values
1035       *
1036       * @return array an array where the array keys are the region names, and the array
1037       * values are empty arrays.
1038       */
1039      protected function prepare_per_region_arrays() {
1040          $result = array();
1041          foreach ($this->regions as $region => $notused) {
1042              $result[$region] = array();
1043          }
1044          return $result;
1045      }
1046  
1047      /**
1048       * Create a set of new block instance from a record array
1049       *
1050       * @param array $birecords An array of block instance records
1051       * @return array An array of instantiated block_instance objects
1052       */
1053      protected function create_block_instances($birecords) {
1054          $results = array();
1055          foreach ($birecords as $record) {
1056              if ($blockobject = block_instance($record->blockname, $record, $this->page)) {
1057                  $results[] = $blockobject;
1058              }
1059          }
1060          return $results;
1061      }
1062  
1063      /**
1064       * Create all the block instances for all the blocks that were loaded by
1065       * load_blocks. This is used, for example, to ensure that all blocks get a
1066       * chance to initialise themselves via the {@link block_base::specialize()}
1067       * method, before any output is done.
1068       *
1069       * It is also used to create any blocks that are "requiredbytheme" by the current theme.
1070       * These blocks that are auto-created have requiredbytheme set on the block instance
1071       * so they are only visible on themes that require them.
1072       */
1073      public function create_all_block_instances() {
1074          $missing = false;
1075  
1076          // If there are any un-removable blocks that were not created - force them.
1077          $requiredbytheme = $this->get_required_by_theme_block_types();
1078          if (!$this->fakeblocksonly) {
1079              foreach ($requiredbytheme as $forced) {
1080                  if (empty($forced)) {
1081                      continue;
1082                  }
1083                  $found = false;
1084                  foreach ($this->get_regions() as $region) {
1085                      foreach($this->birecordsbyregion[$region] as $instance) {
1086                          if ($instance->blockname == $forced) {
1087                              $found = true;
1088                          }
1089                      }
1090                  }
1091                  if (!$found) {
1092                      $this->add_block_required_by_theme($forced);
1093                      $missing = true;
1094                  }
1095              }
1096          }
1097  
1098          if ($missing) {
1099              // Some blocks were missing. Lets do it again.
1100              $this->birecordsbyregion = null;
1101              $this->load_blocks();
1102          }
1103          foreach ($this->get_regions() as $region) {
1104              $this->ensure_instances_exist($region);
1105          }
1106  
1107      }
1108  
1109      /**
1110       * Add a block that is required by the current theme but has not been
1111       * created yet. This is a special type of block that only shows in themes that
1112       * require it (by listing it in undeletable_block_types).
1113       *
1114       * @param string $blockname the name of the block type.
1115       */
1116      protected function add_block_required_by_theme($blockname) {
1117          global $DB;
1118  
1119          if (empty($this->birecordsbyregion)) {
1120              // No blocks or block regions exist yet.
1121              return;
1122          }
1123  
1124          // Never auto create blocks when we are showing fake blocks only.
1125          if ($this->fakeblocksonly) {
1126              return;
1127          }
1128  
1129          // Never add a duplicate block required by theme.
1130          if ($DB->record_exists('block_instances', array('blockname' => $blockname, 'requiredbytheme' => 1))) {
1131              return;
1132          }
1133  
1134          $systemcontext = context_system::instance();
1135          $defaultregion = $this->get_default_region();
1136          // Add a special system wide block instance only for themes that require it.
1137          $blockinstance = new stdClass;
1138          $blockinstance->blockname = $blockname;
1139          $blockinstance->parentcontextid = $systemcontext->id;
1140          $blockinstance->showinsubcontexts = true;
1141          $blockinstance->requiredbytheme = true;
1142          $blockinstance->pagetypepattern = '*';
1143          $blockinstance->subpagepattern = null;
1144          $blockinstance->defaultregion = $defaultregion;
1145          $blockinstance->defaultweight = 0;
1146          $blockinstance->configdata = '';
1147          $blockinstance->timecreated = time();
1148          $blockinstance->timemodified = $blockinstance->timecreated;
1149          $blockinstance->id = $DB->insert_record('block_instances', $blockinstance);
1150  
1151          // Ensure the block context is created.
1152          context_block::instance($blockinstance->id);
1153  
1154          // If the new instance was created, allow it to do additional setup.
1155          if ($block = block_instance($blockname, $blockinstance)) {
1156              $block->instance_create();
1157          }
1158      }
1159  
1160      /**
1161       * Return an array of content objects from a set of block instances
1162       *
1163       * @param array $instances An array of block instances
1164       * @param renderer_base The renderer to use.
1165       * @param string $region the region name.
1166       * @return array An array of block_content (and possibly block_move_target) objects.
1167       */
1168      protected function create_block_contents($instances, $output, $region) {
1169          $results = array();
1170  
1171          $lastweight = 0;
1172          $lastblock = 0;
1173          if ($this->movingblock) {
1174              $first = reset($instances);
1175              if ($first) {
1176                  $lastweight = $first->instance->weight - 2;
1177              }
1178          }
1179  
1180          foreach ($instances as $instance) {
1181              $content = $instance->get_content_for_output($output);
1182              if (empty($content)) {
1183                  continue;
1184              }
1185  
1186              if ($this->movingblock && $lastweight != $instance->instance->weight &&
1187                      $content->blockinstanceid != $this->movingblock && $lastblock != $this->movingblock) {
1188                  $results[] = new block_move_target($this->get_move_target_url($region, ($lastweight + $instance->instance->weight)/2));
1189              }
1190  
1191              if ($content->blockinstanceid == $this->movingblock) {
1192                  $content->add_class('beingmoved');
1193                  $content->annotation .= get_string('movingthisblockcancel', 'block',
1194                          html_writer::link($this->page->url, get_string('cancel')));
1195              }
1196  
1197              $results[] = $content;
1198              $lastweight = $instance->instance->weight;
1199              $lastblock = $instance->instance->id;
1200          }
1201  
1202          if ($this->movingblock && $lastblock != $this->movingblock) {
1203              $results[] = new block_move_target($this->get_move_target_url($region, $lastweight + 1));
1204          }
1205          return $results;
1206      }
1207  
1208      /**
1209       * Ensure block instances exist for a given region
1210       *
1211       * @param string $region Check for bi's with the instance with this name
1212       */
1213      protected function ensure_instances_exist($region) {
1214          $this->check_region_is_known($region);
1215          if (!array_key_exists($region, $this->blockinstances)) {
1216              $this->blockinstances[$region] =
1217                      $this->create_block_instances($this->birecordsbyregion[$region]);
1218          }
1219      }
1220  
1221      /**
1222       * Ensure that there is some content within the given region
1223       *
1224       * @param string $region The name of the region to check
1225       */
1226      public function ensure_content_created($region, $output) {
1227          $this->ensure_instances_exist($region);
1228  
1229          if (!has_capability('moodle/block:view', $this->page->context) ) {
1230              $this->visibleblockcontent[$region] = [];
1231              return;
1232          }
1233  
1234          if (!array_key_exists($region, $this->visibleblockcontent)) {
1235              $contents = array();
1236              if (array_key_exists($region, $this->extracontent)) {
1237                  $contents = $this->extracontent[$region];
1238              }
1239              $contents = array_merge($contents, $this->create_block_contents($this->blockinstances[$region], $output, $region));
1240              if (($region == $this->defaultregion) && (!isset($this->page->theme->addblockposition) ||
1241                      $this->page->theme->addblockposition == BLOCK_ADDBLOCK_POSITION_DEFAULT)) {
1242                  $addblockui = block_add_block_ui($this->page, $output);
1243                  if ($addblockui) {
1244                      $contents[] = $addblockui;
1245                  }
1246              }
1247              $this->visibleblockcontent[$region] = $contents;
1248          }
1249      }
1250  
1251  /// Process actions from the URL ===============================================
1252  
1253      /**
1254       * Get the appropriate list of editing icons for a block. This is used
1255       * to set {@link block_contents::$controls} in {@link block_base::get_contents_for_output()}.
1256       *
1257       * @param $output The core_renderer to use when generating the output. (Need to get icon paths.)
1258       * @return an array in the format for {@link block_contents::$controls}
1259       */
1260      public function edit_controls($block) {
1261          global $CFG;
1262  
1263          $controls = array();
1264          $actionurl = $this->page->url->out(false, array('sesskey'=> sesskey()));
1265          $blocktitle = $block->title;
1266          if (empty($blocktitle)) {
1267              $blocktitle = $block->arialabel;
1268          }
1269  
1270          if ($this->page->user_can_edit_blocks()) {
1271              // Move icon.
1272              $str = new lang_string('moveblock', 'block', $blocktitle);
1273              $controls[] = new action_menu_link_primary(
1274                  new moodle_url($actionurl, array('bui_moveid' => $block->instance->id)),
1275                  new pix_icon('t/move', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1276                  $str,
1277                  array('class' => 'editing_move')
1278              );
1279  
1280          }
1281  
1282          if ($this->page->user_can_edit_blocks() || $block->user_can_edit()) {
1283              // Edit config icon - always show - needed for positioning UI.
1284              $str = new lang_string('configureblock', 'block', $blocktitle);
1285              $editactionurl = new moodle_url($actionurl, ['bui_editid' => $block->instance->id]);
1286              $editactionurl->remove_params(['sesskey']);
1287  
1288              // Handle editing block on admin index page, prevent the page redirecting before block action can begin.
1289              if ($editactionurl->compare(new moodle_url('/admin/index.php'), URL_MATCH_BASE)) {
1290                  $editactionurl->param('cache', 1);
1291              }
1292  
1293              $controls[] = new action_menu_link_secondary(
1294                  $editactionurl,
1295                  new pix_icon('t/edit', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1296                  $str,
1297                  array('class' => 'editing_edit')
1298              );
1299  
1300          }
1301  
1302          if ($this->page->user_can_edit_blocks() && $block->instance_can_be_hidden()) {
1303              // Show/hide icon.
1304              if ($block->instance->visible) {
1305                  $str = new lang_string('hideblock', 'block', $blocktitle);
1306                  $url = new moodle_url($actionurl, array('bui_hideid' => $block->instance->id));
1307                  $icon = new pix_icon('t/hide', $str, 'moodle', array('class' => 'iconsmall', 'title' => ''));
1308                  $attributes = array('class' => 'editing_hide');
1309              } else {
1310                  $str = new lang_string('showblock', 'block', $blocktitle);
1311                  $url = new moodle_url($actionurl, array('bui_showid' => $block->instance->id));
1312                  $icon = new pix_icon('t/show', $str, 'moodle', array('class' => 'iconsmall', 'title' => ''));
1313                  $attributes = array('class' => 'editing_show');
1314              }
1315              $controls[] = new action_menu_link_secondary($url, $icon, $str, $attributes);
1316          }
1317  
1318          // Assign roles.
1319          if (get_assignable_roles($block->context, ROLENAME_SHORT)) {
1320              $rolesurl = new moodle_url('/admin/roles/assign.php', array('contextid' => $block->context->id,
1321                  'returnurl' => $this->page->url->out_as_local_url()));
1322              $str = new lang_string('assignrolesinblock', 'block', $blocktitle);
1323              $controls[] = new action_menu_link_secondary(
1324                  $rolesurl,
1325                  new pix_icon('i/assignroles', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1326                  $str, array('class' => 'editing_assignroles')
1327              );
1328          }
1329  
1330          // Permissions.
1331          if (has_capability('moodle/role:review', $block->context) or get_overridable_roles($block->context)) {
1332              $rolesurl = new moodle_url('/admin/roles/permissions.php', array('contextid' => $block->context->id,
1333                  'returnurl' => $this->page->url->out_as_local_url()));
1334              $str = get_string('permissions', 'role');
1335              $controls[] = new action_menu_link_secondary(
1336                  $rolesurl,
1337                  new pix_icon('i/permissions', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1338                  $str, array('class' => 'editing_permissions')
1339              );
1340          }
1341  
1342          // Change permissions.
1343          if (has_any_capability(array('moodle/role:safeoverride', 'moodle/role:override', 'moodle/role:assign'), $block->context)) {
1344              $rolesurl = new moodle_url('/admin/roles/check.php', array('contextid' => $block->context->id,
1345                  'returnurl' => $this->page->url->out_as_local_url()));
1346              $str = get_string('checkpermissions', 'role');
1347              $controls[] = new action_menu_link_secondary(
1348                  $rolesurl,
1349                  new pix_icon('i/checkpermissions', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1350                  $str, array('class' => 'editing_checkroles')
1351              );
1352          }
1353  
1354          if ($this->user_can_delete_block($block)) {
1355              // Delete icon.
1356              $str = new lang_string('deleteblock', 'block', $blocktitle);
1357              $deleteactionurl = new moodle_url($actionurl, ['bui_deleteid' => $block->instance->id]);
1358              $deleteactionurl->remove_params(['sesskey']);
1359  
1360              // Handle deleting block on admin index page, prevent the page redirecting before block action can begin.
1361              if ($deleteactionurl->compare(new moodle_url('/admin/index.php'), URL_MATCH_BASE)) {
1362                  $deleteactionurl->param('cache', 1);
1363              }
1364  
1365              $controls[] = new action_menu_link_secondary(
1366                  $deleteactionurl,
1367                  new pix_icon('t/delete', $str, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1368                  $str,
1369                  array('class' => 'editing_delete')
1370              );
1371          }
1372  
1373          if (!empty($CFG->contextlocking) && has_capability('moodle/site:managecontextlocks', $block->context)) {
1374              $parentcontext = $block->context->get_parent_context();
1375              if (empty($parentcontext) || empty($parentcontext->locked)) {
1376                  if ($block->context->locked) {
1377                      $lockicon = 'i/unlock';
1378                      $lockstring = get_string('managecontextunlock', 'admin');
1379                  } else {
1380                      $lockicon = 'i/lock';
1381                      $lockstring = get_string('managecontextlock', 'admin');
1382                  }
1383                  $controls[] = new action_menu_link_secondary(
1384                      new moodle_url(
1385                          '/admin/lock.php',
1386                          [
1387                              'id' => $block->context->id,
1388                          ]
1389                      ),
1390                      new pix_icon($lockicon, $lockstring, 'moodle', array('class' => 'iconsmall', 'title' => '')),
1391                      $lockstring,
1392                      ['class' => 'editing_lock']
1393                  );
1394              }
1395          }
1396  
1397          return $controls;
1398      }
1399  
1400      /**
1401       * @param block_base $block a block that appears on this page.
1402       * @return boolean boolean whether the currently logged in user is allowed to delete this block.
1403       */
1404      protected function user_can_delete_block($block) {
1405          return $this->page->user_can_edit_blocks() && $block->user_can_edit() &&
1406                  $block->user_can_addto($this->page) &&
1407                  !in_array($block->instance->blockname, self::get_undeletable_block_types()) &&
1408                  !in_array($block->instance->blockname, $this->get_required_by_theme_block_types());
1409      }
1410  
1411      /**
1412       * Process any block actions that were specified in the URL.
1413       *
1414       * @return boolean true if anything was done. False if not.
1415       */
1416      public function process_url_actions() {
1417          if (!$this->page->user_is_editing()) {
1418              return false;
1419          }
1420          return $this->process_url_add() || $this->process_url_delete() ||
1421              $this->process_url_show_hide() || $this->process_url_edit() ||
1422              $this->process_url_move();
1423      }
1424  
1425      /**
1426       * Handle adding a block.
1427       * @return boolean true if anything was done. False if not.
1428       */
1429      public function process_url_add() {
1430          global $CFG, $PAGE, $OUTPUT;
1431  
1432          $blocktype = optional_param('bui_addblock', null, PARAM_PLUGIN);
1433          if ($blocktype === null) {
1434              return false;
1435          }
1436  
1437          require_sesskey();
1438  
1439          if (!$this->page->user_can_edit_blocks()) {
1440              throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('addblock'));
1441          }
1442  
1443          $addableblocks = $this->get_addable_blocks();
1444  
1445          if ($blocktype === '') {
1446              // Display add block selection.
1447              $addpage = new moodle_page();
1448              $addpage->set_pagelayout('admin');
1449              $addpage->blocks->show_only_fake_blocks(true);
1450              $addpage->set_course($this->page->course);
1451              $addpage->set_context($this->page->context);
1452              if ($this->page->cm) {
1453                  $addpage->set_cm($this->page->cm);
1454              }
1455  
1456              $addpagebase = str_replace($CFG->wwwroot . '/', '/', $this->page->url->out_omit_querystring());
1457              $addpageparams = $this->page->url->params();
1458              $addpage->set_url($addpagebase, $addpageparams);
1459              $addpage->set_block_actions_done();
1460              // At this point we are going to display the block selector, overwrite global $PAGE ready for this.
1461              $PAGE = $addpage;
1462              // Some functions use $OUTPUT so we need to replace that too.
1463              $OUTPUT = $addpage->get_renderer('core');
1464  
1465              $site = get_site();
1466              $straddblock = get_string('addblock');
1467  
1468              $PAGE->navbar->add($straddblock);
1469              $PAGE->set_title($straddblock);
1470              $PAGE->set_heading($site->fullname);
1471              echo $OUTPUT->header();
1472              echo $OUTPUT->heading($straddblock);
1473  
1474              if (!$addableblocks) {
1475                  echo $OUTPUT->box(get_string('noblockstoaddhere'));
1476                  echo $OUTPUT->container($OUTPUT->action_link($addpage->url, get_string('back')), 'mx-3 mb-1');
1477              } else {
1478                  $url = new moodle_url($addpage->url, array('sesskey' => sesskey()));
1479                  echo $OUTPUT->render_from_template('core/add_block_body',
1480                      ['blocks' => array_values($addableblocks),
1481                       'url' => '?' . $url->get_query_string(false)]);
1482                  echo $OUTPUT->container($OUTPUT->action_link($addpage->url, get_string('cancel')), 'mx-3 mb-1');
1483              }
1484  
1485              echo $OUTPUT->footer();
1486              // Make sure that nothing else happens after we have displayed this form.
1487              exit;
1488          }
1489  
1490          if (!array_key_exists($blocktype, $addableblocks)) {
1491              throw new moodle_exception('cannotaddthisblocktype', '', $this->page->url->out(), $blocktype);
1492          }
1493  
1494          $this->add_block_at_end_of_default_region($blocktype);
1495  
1496          // If the page URL was a guess, it will contain the bui_... param, so we must make sure it is not there.
1497          $this->page->ensure_param_not_in_url('bui_addblock');
1498  
1499          return true;
1500      }
1501  
1502      /**
1503       * Handle deleting a block.
1504       * @return boolean true if anything was done. False if not.
1505       */
1506      public function process_url_delete() {
1507          global $CFG, $PAGE, $OUTPUT;
1508  
1509          $blockid = optional_param('bui_deleteid', null, PARAM_INT);
1510          $confirmdelete = optional_param('bui_confirm', null, PARAM_INT);
1511  
1512          if (!$blockid) {
1513              return false;
1514          }
1515  
1516          $block = $this->page->blocks->find_instance($blockid);
1517          if (!$this->user_can_delete_block($block)) {
1518              throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('deleteablock'));
1519          }
1520  
1521          if (!$confirmdelete) {
1522              $deletepage = new moodle_page();
1523              $deletepage->set_pagelayout('admin');
1524              $deletepage->blocks->show_only_fake_blocks(true);
1525              $deletepage->set_course($this->page->course);
1526              $deletepage->set_context($this->page->context);
1527              if ($this->page->cm) {
1528                  $deletepage->set_cm($this->page->cm);
1529              }
1530  
1531              $deleteurlbase = str_replace($CFG->wwwroot . '/', '/', $this->page->url->out_omit_querystring());
1532              $deleteurlparams = $this->page->url->params();
1533              $deletepage->set_url($deleteurlbase, $deleteurlparams);
1534              $deletepage->set_block_actions_done();
1535              // At this point we are either going to redirect, or display the form, so
1536              // overwrite global $PAGE ready for this. (Formslib refers to it.)
1537              $PAGE = $deletepage;
1538              //some functions like MoodleQuickForm::addHelpButton use $OUTPUT so we need to replace that too
1539              $output = $deletepage->get_renderer('core');
1540              $OUTPUT = $output;
1541  
1542              $site = get_site();
1543              $blocktitle = $block->get_title();
1544              $strdeletecheck = get_string('deletecheck', 'block', $blocktitle);
1545              $message = get_string('deleteblockcheck', 'block', $blocktitle);
1546  
1547              // If the block is being shown in sub contexts display a warning.
1548              if ($block->instance->showinsubcontexts == 1) {
1549                  $parentcontext = context::instance_by_id($block->instance->parentcontextid);
1550                  $systemcontext = context_system::instance();
1551                  $messagestring = new stdClass();
1552                  $messagestring->location = $parentcontext->get_context_name();
1553  
1554                  // Checking for blocks that may have visibility on the front page and pages added on that.
1555                  if ($parentcontext->id != $systemcontext->id && is_inside_frontpage($parentcontext)) {
1556                      $messagestring->pagetype = get_string('showonfrontpageandsubs', 'block');
1557                  } else {
1558                      $pagetypes = generate_page_type_patterns($this->page->pagetype, $parentcontext);
1559                      $messagestring->pagetype = $block->instance->pagetypepattern;
1560                      if (isset($pagetypes[$block->instance->pagetypepattern])) {
1561                          $messagestring->pagetype = $pagetypes[$block->instance->pagetypepattern];
1562                      }
1563                  }
1564  
1565                  $message = get_string('deleteblockwarning', 'block', $messagestring);
1566              }
1567  
1568              $PAGE->navbar->add($strdeletecheck);
1569              $PAGE->set_title($blocktitle . ': ' . $strdeletecheck);
1570              $PAGE->set_heading($site->fullname);
1571              echo $OUTPUT->header();
1572              $confirmurl = new moodle_url($deletepage->url, array('sesskey' => sesskey(), 'bui_deleteid' => $block->instance->id, 'bui_confirm' => 1));
1573              $cancelurl = new moodle_url($deletepage->url);
1574              $yesbutton = new single_button($confirmurl, get_string('yes'));
1575              $nobutton = new single_button($cancelurl, get_string('no'));
1576              echo $OUTPUT->confirm($message, $yesbutton, $nobutton);
1577              echo $OUTPUT->footer();
1578              // Make sure that nothing else happens after we have displayed this form.
1579              exit;
1580          } else {
1581              require_sesskey();
1582  
1583              blocks_delete_instance($block->instance);
1584              // bui_deleteid and bui_confirm should not be in the PAGE url.
1585              $this->page->ensure_param_not_in_url('bui_deleteid');
1586              $this->page->ensure_param_not_in_url('bui_confirm');
1587              return true;
1588          }
1589      }
1590  
1591      /**
1592       * Handle showing or hiding a block.
1593       * @return boolean true if anything was done. False if not.
1594       */
1595      public function process_url_show_hide() {
1596          if ($blockid = optional_param('bui_hideid', null, PARAM_INT)) {
1597              $newvisibility = 0;
1598          } else if ($blockid = optional_param('bui_showid', null, PARAM_INT)) {
1599              $newvisibility = 1;
1600          } else {
1601              return false;
1602          }
1603  
1604          require_sesskey();
1605  
1606          $block = $this->page->blocks->find_instance($blockid);
1607  
1608          if (!$this->page->user_can_edit_blocks()) {
1609              throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('hideshowblocks'));
1610          } else if (!$block->instance_can_be_hidden()) {
1611              return false;
1612          }
1613  
1614          blocks_set_visibility($block->instance, $this->page, $newvisibility);
1615  
1616          // If the page URL was a guses, it will contain the bui_... param, so we must make sure it is not there.
1617          $this->page->ensure_param_not_in_url('bui_hideid');
1618          $this->page->ensure_param_not_in_url('bui_showid');
1619  
1620          return true;
1621      }
1622  
1623      /**
1624       * Handle showing/processing the submission from the block editing form.
1625       * @return boolean true if the form was submitted and the new config saved. Does not
1626       *      return if the editing form was displayed. False otherwise.
1627       */
1628      public function process_url_edit() {
1629          global $CFG, $DB, $PAGE, $OUTPUT;
1630  
1631          $blockid = optional_param('bui_editid', null, PARAM_INT);
1632          if (!$blockid) {
1633              return false;
1634          }
1635  
1636          require_once($CFG->dirroot . '/blocks/edit_form.php');
1637  
1638          $block = $this->find_instance($blockid);
1639  
1640          if (!$block->user_can_edit() && !$this->page->user_can_edit_blocks()) {
1641              throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('editblock'));
1642          }
1643  
1644          $editpage = new moodle_page();
1645          $editpage->set_pagelayout('admin');
1646          $editpage->blocks->show_only_fake_blocks(true);
1647          $editpage->set_course($this->page->course);
1648          //$editpage->set_context($block->context);
1649          $editpage->set_context($this->page->context);
1650          if ($this->page->cm) {
1651              $editpage->set_cm($this->page->cm);
1652          }
1653          $editurlbase = str_replace($CFG->wwwroot . '/', '/', $this->page->url->out_omit_querystring());
1654          $editurlparams = $this->page->url->params();
1655          $editurlparams['bui_editid'] = $blockid;
1656          $editpage->set_url($editurlbase, $editurlparams);
1657          $editpage->set_block_actions_done();
1658          // At this point we are either going to redirect, or display the form, so
1659          // overwrite global $PAGE ready for this. (Formslib refers to it.)
1660          $PAGE = $editpage;
1661          //some functions like MoodleQuickForm::addHelpButton use $OUTPUT so we need to replace that to
1662          $output = $editpage->get_renderer('core');
1663          $OUTPUT = $output;
1664  
1665          $formfile = $CFG->dirroot . '/blocks/' . $block->name() . '/edit_form.php';
1666          if (is_readable($formfile)) {
1667              require_once($formfile);
1668              $classname = 'block_' . $block->name() . '_edit_form';
1669              if (!class_exists($classname)) {
1670                  $classname = 'block_edit_form';
1671              }
1672          } else {
1673              $classname = 'block_edit_form';
1674          }
1675  
1676          $mform = new $classname($editpage->url, $block, $this->page);
1677          $mform->set_data($block->instance);
1678  
1679          if ($mform->is_cancelled()) {
1680              redirect($this->page->url);
1681  
1682          } else if ($data = $mform->get_data()) {
1683              $bi = new stdClass;
1684              $bi->id = $block->instance->id;
1685  
1686              // This may get overwritten by the special case handling below.
1687              $bi->pagetypepattern = $data->bui_pagetypepattern;
1688              $bi->showinsubcontexts = (bool) $data->bui_contexts;
1689              if (empty($data->bui_subpagepattern) || $data->bui_subpagepattern == '%@NULL@%') {
1690                  $bi->subpagepattern = null;
1691              } else {
1692                  $bi->subpagepattern = $data->bui_subpagepattern;
1693              }
1694  
1695              $systemcontext = context_system::instance();
1696              $frontpagecontext = context_course::instance(SITEID);
1697              $parentcontext = context::instance_by_id($data->bui_parentcontextid);
1698  
1699              // Updating stickiness and contexts.  See MDL-21375 for details.
1700              if (has_capability('moodle/site:manageblocks', $parentcontext)) { // Check permissions in destination
1701  
1702                  // Explicitly set the default context
1703                  $bi->parentcontextid = $parentcontext->id;
1704  
1705                  if ($data->bui_editingatfrontpage) {   // The block is being edited on the front page
1706  
1707                      // The interface here is a special case because the pagetype pattern is
1708                      // totally derived from the context menu.  Here are the excpetions.   MDL-30340
1709  
1710                      switch ($data->bui_contexts) {
1711                          case BUI_CONTEXTS_ENTIRE_SITE:
1712                              // The user wants to show the block across the entire site
1713                              $bi->parentcontextid = $systemcontext->id;
1714                              $bi->showinsubcontexts = true;
1715                              $bi->pagetypepattern  = '*';
1716                              break;
1717                          case BUI_CONTEXTS_FRONTPAGE_SUBS:
1718                              // The user wants the block shown on the front page and all subcontexts
1719                              $bi->parentcontextid = $frontpagecontext->id;
1720                              $bi->showinsubcontexts = true;
1721                              $bi->pagetypepattern  = '*';
1722                              break;
1723                          case BUI_CONTEXTS_FRONTPAGE_ONLY:
1724                              // The user want to show the front page on the frontpage only
1725                              $bi->parentcontextid = $frontpagecontext->id;
1726                              $bi->showinsubcontexts = false;
1727                              $bi->pagetypepattern  = 'site-index';
1728                              // This is the only relevant page type anyway but we'll set it explicitly just
1729                              // in case the front page grows site-index-* subpages of its own later
1730                              break;
1731                      }
1732                  }
1733              }
1734  
1735              $bits = explode('-', $bi->pagetypepattern);
1736              // hacks for some contexts
1737              if (($parentcontext->contextlevel == CONTEXT_COURSE) && ($parentcontext->instanceid != SITEID)) {
1738                  // For course context
1739                  // is page type pattern is mod-*, change showinsubcontext to 1
1740                  if ($bits[0] == 'mod' || $bi->pagetypepattern == '*') {
1741                      $bi->showinsubcontexts = 1;
1742                  } else {
1743                      $bi->showinsubcontexts = 0;
1744                  }
1745              } else  if ($parentcontext->contextlevel == CONTEXT_USER) {
1746                  // for user context
1747                  // subpagepattern should be null
1748                  if ($bits[0] == 'user' or $bits[0] == 'my') {
1749                      // we don't need subpagepattern in usercontext
1750                      $bi->subpagepattern = null;
1751                  }
1752              }
1753  
1754              $bi->defaultregion = $data->bui_defaultregion;
1755              $bi->defaultweight = $data->bui_defaultweight;
1756              $bi->timemodified = time();
1757              $DB->update_record('block_instances', $bi);
1758  
1759              if (!empty($block->config)) {
1760                  $config = clone($block->config);
1761              } else {
1762                  $config = new stdClass;
1763              }
1764              foreach ($data as $configfield => $value) {
1765                  if (strpos($configfield, 'config_') !== 0) {
1766                      continue;
1767                  }
1768                  $field = substr($configfield, 7);
1769                  $config->$field = $value;
1770              }
1771              $block->instance_config_save($config);
1772  
1773              $bp = new stdClass;
1774              $bp->visible = $data->bui_visible;
1775              $bp->region = $data->bui_region;
1776              $bp->weight = $data->bui_weight;
1777              $needbprecord = !$data->bui_visible || $data->bui_region != $data->bui_defaultregion ||
1778                      $data->bui_weight != $data->bui_defaultweight;
1779  
1780              if ($block->instance->blockpositionid && !$needbprecord) {
1781                  $DB->delete_records('block_positions', array('id' => $block->instance->blockpositionid));
1782  
1783              } else if ($block->instance->blockpositionid && $needbprecord) {
1784                  $bp->id = $block->instance->blockpositionid;
1785                  $DB->update_record('block_positions', $bp);
1786  
1787              } else if ($needbprecord) {
1788                  $bp->blockinstanceid = $block->instance->id;
1789                  $bp->contextid = $this->page->context->id;
1790                  $bp->pagetype = $this->page->pagetype;
1791                  if ($this->page->subpage) {
1792                      $bp->subpage = $this->page->subpage;
1793                  } else {
1794                      $bp->subpage = '';
1795                  }
1796                  $DB->insert_record('block_positions', $bp);
1797              }
1798  
1799              redirect($this->page->url);
1800  
1801          } else {
1802              $strheading = get_string('blockconfiga', 'moodle', $block->get_title());
1803              $editpage->set_title($strheading);
1804              $editpage->set_heading($strheading);
1805              $bits = explode('-', $this->page->pagetype);
1806              if ($bits[0] == 'tag' && !empty($this->page->subpage)) {
1807                  // better navbar for tag pages
1808                  $editpage->navbar->add(get_string('tags'), new moodle_url('/tag/'));
1809                  $tag = core_tag_tag::get($this->page->subpage);
1810                  // tag search page doesn't have subpageid
1811                  if ($tag) {
1812                      $editpage->navbar->add($tag->get_display_name(), $tag->get_view_url());
1813                  }
1814              }
1815              $editpage->navbar->add($block->get_title());
1816              $editpage->navbar->add(get_string('configuration'));
1817              echo $output->header();
1818              echo $output->heading($strheading, 2);
1819              $mform->display();
1820              echo $output->footer();
1821              exit;
1822          }
1823      }
1824  
1825      /**
1826       * Handle showing/processing the submission from the block editing form.
1827       * @return boolean true if the form was submitted and the new config saved. Does not
1828       *      return if the editing form was displayed. False otherwise.
1829       */
1830      public function process_url_move() {
1831          global $CFG, $DB, $PAGE;
1832  
1833          $blockid = optional_param('bui_moveid', null, PARAM_INT);
1834          if (!$blockid) {
1835              return false;
1836          }
1837  
1838          require_sesskey();
1839  
1840          $block = $this->find_instance($blockid);
1841  
1842          if (!$this->page->user_can_edit_blocks()) {
1843              throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('editblock'));
1844          }
1845  
1846          $newregion = optional_param('bui_newregion', '', PARAM_ALPHANUMEXT);
1847          $newweight = optional_param('bui_newweight', null, PARAM_FLOAT);
1848          if (!$newregion || is_null($newweight)) {
1849              // Don't have a valid target position yet, must be just starting the move.
1850              $this->movingblock = $blockid;
1851              $this->page->ensure_param_not_in_url('bui_moveid');
1852              return false;
1853          }
1854  
1855          if (!$this->is_known_region($newregion)) {
1856              throw new moodle_exception('unknownblockregion', '', $this->page->url, $newregion);
1857          }
1858  
1859          // Move this block. This may involve moving other nearby blocks.
1860          $blocks = $this->birecordsbyregion[$newregion];
1861  
1862          $maxweight = self::MAX_WEIGHT;
1863          $minweight = -self::MAX_WEIGHT;
1864  
1865          // Initialise the used weights and spareweights array with the default values
1866          $spareweights = array();
1867          $usedweights = array();
1868          for ($i = $minweight; $i <= $maxweight; $i++) {
1869              $spareweights[$i] = $i;
1870              $usedweights[$i] = array();
1871          }
1872  
1873          // Check each block and sort out where we have used weights
1874          foreach ($blocks as $bi) {
1875              if ($bi->weight > $maxweight) {
1876                  // If this statement is true then the blocks weight is more than the
1877                  // current maximum. To ensure that we can get the best block position
1878                  // we will initialise elements within the usedweights and spareweights
1879                  // arrays between the blocks weight (which will then be the new max) and
1880                  // the current max
1881                  $parseweight = $bi->weight;
1882                  while (!array_key_exists($parseweight, $usedweights)) {
1883                      $usedweights[$parseweight] = array();
1884                      $spareweights[$parseweight] = $parseweight;
1885                      $parseweight--;
1886                  }
1887                  $maxweight = $bi->weight;
1888              } else if ($bi->weight < $minweight) {
1889                  // As above except this time the blocks weight is LESS than the
1890                  // the current minimum, so we will initialise the array from the
1891                  // blocks weight (new minimum) to the current minimum
1892                  $parseweight = $bi->weight;
1893                  while (!array_key_exists($parseweight, $usedweights)) {
1894                      $usedweights[$parseweight] = array();
1895                      $spareweights[$parseweight] = $parseweight;
1896                      $parseweight++;
1897                  }
1898                  $minweight = $bi->weight;
1899              }
1900              if ($bi->id != $block->instance->id) {
1901                  unset($spareweights[$bi->weight]);
1902                  $usedweights[$bi->weight][] = $bi->id;
1903              }
1904          }
1905  
1906          // First we find the nearest gap in the list of weights.
1907          $bestdistance = max(abs($newweight - self::MAX_WEIGHT), abs($newweight + self::MAX_WEIGHT)) + 1;
1908          $bestgap = null;
1909          foreach ($spareweights as $spareweight) {
1910              if (abs($newweight - $spareweight) < $bestdistance) {
1911                  $bestdistance = abs($newweight - $spareweight);
1912                  $bestgap = $spareweight;
1913              }
1914          }
1915  
1916          // If there is no gap, we have to go outside -self::MAX_WEIGHT .. self::MAX_WEIGHT.
1917          if (is_null($bestgap)) {
1918              $bestgap = self::MAX_WEIGHT + 1;
1919              while (!empty($usedweights[$bestgap])) {
1920                  $bestgap++;
1921              }
1922          }
1923  
1924          // Now we know the gap we are aiming for, so move all the blocks along.
1925          if ($bestgap < $newweight) {
1926              $newweight = floor($newweight);
1927              for ($weight = $bestgap + 1; $weight <= $newweight; $weight++) {
1928                  if (array_key_exists($weight, $usedweights)) {
1929                      foreach ($usedweights[$weight] as $biid) {
1930                          $this->reposition_block($biid, $newregion, $weight - 1);
1931                      }
1932                  }
1933              }
1934              $this->reposition_block($block->instance->id, $newregion, $newweight);
1935          } else {
1936              $newweight = ceil($newweight);
1937              for ($weight = $bestgap - 1; $weight >= $newweight; $weight--) {
1938                  if (array_key_exists($weight, $usedweights)) {
1939                      foreach ($usedweights[$weight] as $biid) {
1940                          $this->reposition_block($biid, $newregion, $weight + 1);
1941                      }
1942                  }
1943              }
1944              $this->reposition_block($block->instance->id, $newregion, $newweight);
1945          }
1946  
1947          $this->page->ensure_param_not_in_url('bui_moveid');
1948          $this->page->ensure_param_not_in_url('bui_newregion');
1949          $this->page->ensure_param_not_in_url('bui_newweight');
1950          return true;
1951      }
1952  
1953      /**
1954       * Turns the display of normal blocks either on or off.
1955       *
1956       * @param bool $setting
1957       */
1958      public function show_only_fake_blocks($setting = true) {
1959          $this->fakeblocksonly = $setting;
1960      }
1961  }
1962  
1963  /// Helper functions for working with block classes ============================
1964  
1965  /**
1966   * Call a class method (one that does not require a block instance) on a block class.
1967   *
1968   * @param string $blockname the name of the block.
1969   * @param string $method the method name.
1970   * @param array $param parameters to pass to the method.
1971   * @return mixed whatever the method returns.
1972   */
1973  function block_method_result($blockname, $method, $param = NULL) {
1974      if(!block_load_class($blockname)) {
1975          return NULL;
1976      }
1977      return call_user_func(array('block_'.$blockname, $method), $param);
1978  }
1979  
1980  /**
1981   * Returns a new instance of the specified block instance id.
1982   *
1983   * @param int $blockinstanceid
1984   * @return block_base the requested block instance.
1985   */
1986  function block_instance_by_id($blockinstanceid) {
1987      global $DB;
1988  
1989      $blockinstance = $DB->get_record('block_instances', ['id' => $blockinstanceid]);
1990      $instance = block_instance($blockinstance->blockname, $blockinstance);
1991      return $instance;
1992  }
1993  
1994  /**
1995   * Creates a new instance of the specified block class.
1996   *
1997   * @param string $blockname the name of the block.
1998   * @param $instance block_instances DB table row (optional).
1999   * @param moodle_page $page the page this block is appearing on.
2000   * @return block_base the requested block instance.
2001   */
2002  function block_instance($blockname, $instance = NULL, $page = NULL) {
2003      if(!block_load_class($blockname)) {
2004          return false;
2005      }
2006      $classname = 'block_'.$blockname;
2007      $retval = new $classname;
2008      if($instance !== NULL) {
2009          if (is_null($page)) {
2010              global $PAGE;
2011              $page = $PAGE;
2012          }
2013          $retval->_load_instance($instance, $page);
2014      }
2015      return $retval;
2016  }
2017  
2018  /**
2019   * Load the block class for a particular type of block.
2020   *
2021   * @param string $blockname the name of the block.
2022   * @return boolean success or failure.
2023   */
2024  function block_load_class($blockname) {
2025      global $CFG;
2026  
2027      if(empty($blockname)) {
2028          return false;
2029      }
2030  
2031      $classname = 'block_'.$blockname;
2032  
2033      if(class_exists($classname)) {
2034          return true;
2035      }
2036  
2037      $blockpath = $CFG->dirroot.'/blocks/'.$blockname.'/block_'.$blockname.'.php';
2038  
2039      if (file_exists($blockpath)) {
2040          require_once($CFG->dirroot.'/blocks/moodleblock.class.php');
2041          include_once($blockpath);
2042      }else{
2043          //debugging("$blockname code does not exist in $blockpath", DEBUG_DEVELOPER);
2044          return false;
2045      }
2046  
2047      return class_exists($classname);
2048  }
2049  
2050  /**
2051   * Given a specific page type, return all the page type patterns that might
2052   * match it.
2053   *
2054   * @param string $pagetype for example 'course-view-weeks' or 'mod-quiz-view'.
2055   * @return array an array of all the page type patterns that might match this page type.
2056   */
2057  function matching_page_type_patterns($pagetype) {
2058      $patterns = array($pagetype);
2059      $bits = explode('-', $pagetype);
2060      if (count($bits) == 3 && $bits[0] == 'mod') {
2061          if ($bits[2] == 'view') {
2062              $patterns[] = 'mod-*-view';
2063          } else if ($bits[2] == 'index') {
2064              $patterns[] = 'mod-*-index';
2065          }
2066      }
2067      while (count($bits) > 0) {
2068          $patterns[] = implode('-', $bits) . '-*';
2069          array_pop($bits);
2070      }
2071      $patterns[] = '*';
2072      return $patterns;
2073  }
2074  
2075  /**
2076   * Give an specific pattern, return all the page type patterns that would also match it.
2077   *
2078   * @param  string $pattern the pattern, e.g. 'mod-forum-*' or 'mod-quiz-view'.
2079   * @return array of all the page type patterns matching.
2080   */
2081  function matching_page_type_patterns_from_pattern($pattern) {
2082      $patterns = array($pattern);
2083      if ($pattern === '*') {
2084          return $patterns;
2085      }
2086  
2087      // Only keep the part before the star because we will append -* to all the bits.
2088      $star = strpos($pattern, '-*');
2089      if ($star !== false) {
2090          $pattern = substr($pattern, 0, $star);
2091      }
2092  
2093      $patterns = array_merge($patterns, matching_page_type_patterns($pattern));
2094      $patterns = array_unique($patterns);
2095  
2096      return $patterns;
2097  }
2098  
2099  /**
2100   * Given a specific page type, parent context and currect context, return all the page type patterns
2101   * that might be used by this block.
2102   *
2103   * @param string $pagetype for example 'course-view-weeks' or 'mod-quiz-view'.
2104   * @param stdClass $parentcontext Block's parent context
2105   * @param stdClass $currentcontext Current context of block
2106   * @return array an array of all the page type patterns that might match this page type.
2107   */
2108  function generate_page_type_patterns($pagetype, $parentcontext = null, $currentcontext = null) {
2109      global $CFG; // Required for includes bellow.
2110  
2111      $bits = explode('-', $pagetype);
2112  
2113      $core = core_component::get_core_subsystems();
2114      $plugins = core_component::get_plugin_types();
2115  
2116      //progressively strip pieces off the page type looking for a match
2117      $componentarray = null;
2118      for ($i = count($bits); $i > 0; $i--) {
2119          $possiblecomponentarray = array_slice($bits, 0, $i);
2120          $possiblecomponent = implode('', $possiblecomponentarray);
2121  
2122          // Check to see if the component is a core component
2123          if (array_key_exists($possiblecomponent, $core) && !empty($core[$possiblecomponent])) {
2124              $libfile = $core[$possiblecomponent].'/lib.php';
2125              if (file_exists($libfile)) {
2126                  require_once($libfile);
2127                  $function = $possiblecomponent.'_page_type_list';
2128                  if (function_exists($function)) {
2129                      if ($patterns = $function($pagetype, $parentcontext, $currentcontext)) {
2130                          break;
2131                      }
2132                  }
2133              }
2134          }
2135  
2136          //check the plugin directory and look for a callback
2137          if (array_key_exists($possiblecomponent, $plugins) && !empty($plugins[$possiblecomponent])) {
2138  
2139              //We've found a plugin type. Look for a plugin name by getting the next section of page type
2140              if (count($bits) > $i) {
2141                  $pluginname = $bits[$i];
2142                  $directory = core_component::get_plugin_directory($possiblecomponent, $pluginname);
2143                  if (!empty($directory)){
2144                      $libfile = $directory.'/lib.php';
2145                      if (file_exists($libfile)) {
2146                          require_once($libfile);
2147                          $function = $possiblecomponent.'_'.$pluginname.'_page_type_list';
2148                          if (!function_exists($function)) {
2149                              $function = $pluginname.'_page_type_list';
2150                          }
2151                          if (function_exists($function)) {
2152                              if ($patterns = $function($pagetype, $parentcontext, $currentcontext)) {
2153                                  break;
2154                              }
2155                          }
2156                      }
2157                  }
2158              }
2159  
2160              //we'll only get to here if we still don't have any patterns
2161              //the plugin type may have a callback
2162              $directory = $plugins[$possiblecomponent];
2163              $libfile = $directory.'/lib.php';
2164              if (file_exists($libfile)) {
2165                  require_once($libfile);
2166                  $function = $possiblecomponent.'_page_type_list';
2167                  if (function_exists($function)) {
2168                      if ($patterns = $function($pagetype, $parentcontext, $currentcontext)) {
2169                          break;
2170                      }
2171                  }
2172              }
2173          }
2174      }
2175  
2176      if (empty($patterns)) {
2177          $patterns = default_page_type_list($pagetype, $parentcontext, $currentcontext);
2178      }
2179  
2180      // Ensure that the * pattern is always available if editing block 'at distance', so
2181      // we always can 'bring back' it to the original context. MDL-30340
2182      if ((!isset($currentcontext) or !isset($parentcontext) or $currentcontext->id != $parentcontext->id) && !isset($patterns['*'])) {
2183          // TODO: We could change the string here, showing its 'bring back' meaning
2184          $patterns['*'] = get_string('page-x', 'pagetype');
2185      }
2186  
2187      return $patterns;
2188  }
2189  
2190  /**
2191   * Generates a default page type list when a more appropriate callback cannot be decided upon.
2192   *
2193   * @param string $pagetype
2194   * @param stdClass $parentcontext
2195   * @param stdClass $currentcontext
2196   * @return array
2197   */
2198  function default_page_type_list($pagetype, $parentcontext = null, $currentcontext = null) {
2199      // Generate page type patterns based on current page type if
2200      // callbacks haven't been defined
2201      $patterns = array($pagetype => $pagetype);
2202      $bits = explode('-', $pagetype);
2203      while (count($bits) > 0) {
2204          $pattern = implode('-', $bits) . '-*';
2205          $pagetypestringname = 'page-'.str_replace('*', 'x', $pattern);
2206          // guessing page type description
2207          if (get_string_manager()->string_exists($pagetypestringname, 'pagetype')) {
2208              $patterns[$pattern] = get_string($pagetypestringname, 'pagetype');
2209          } else {
2210              $patterns[$pattern] = $pattern;
2211          }
2212          array_pop($bits);
2213      }
2214      $patterns['*'] = get_string('page-x', 'pagetype');
2215      return $patterns;
2216  }
2217  
2218  /**
2219   * Generates the page type list for the my moodle page
2220   *
2221   * @param string $pagetype
2222   * @param stdClass $parentcontext
2223   * @param stdClass $currentcontext
2224   * @return array
2225   */
2226  function my_page_type_list($pagetype, $parentcontext = null, $currentcontext = null) {
2227      return array('my-index' => get_string('page-my-index', 'pagetype'));
2228  }
2229  
2230  /**
2231   * Generates the page type list for a module by either locating and using the modules callback
2232   * or by generating a default list.
2233   *
2234   * @param string $pagetype
2235   * @param stdClass $parentcontext
2236   * @param stdClass $currentcontext
2237   * @return array
2238   */
2239  function mod_page_type_list($pagetype, $parentcontext = null, $currentcontext = null) {
2240      $patterns = plugin_page_type_list($pagetype, $parentcontext, $currentcontext);
2241      if (empty($patterns)) {
2242          // if modules don't have callbacks
2243          // generate two default page type patterns for modules only
2244          $bits = explode('-', $pagetype);
2245          $patterns = array($pagetype => $pagetype);
2246          if ($bits[2] == 'view') {
2247              $patterns['mod-*-view'] = get_string('page-mod-x-view', 'pagetype');
2248          } else if ($bits[2] == 'index') {
2249              $patterns['mod-*-index'] = get_string('page-mod-x-index', 'pagetype');
2250          }
2251      }
2252      return $patterns;
2253  }
2254  /// Functions update the blocks if required by the request parameters ==========
2255  
2256  /**
2257   * Return a {@link block_contents} representing the add a new block UI, if
2258   * this user is allowed to see it.
2259   *
2260   * @return block_contents an appropriate block_contents, or null if the user
2261   * cannot add any blocks here.
2262   */
2263  function block_add_block_ui($page, $output) {
2264      global $CFG, $OUTPUT;
2265      if (!$page->user_is_editing() || !$page->user_can_edit_blocks()) {
2266          return null;
2267      }
2268  
2269      $bc = new block_contents();
2270      $bc->title = get_string('addblock');
2271      $bc->add_class('block_adminblock');
2272      $bc->attributes['data-block'] = 'adminblock';
2273  
2274      $missingblocks = $page->blocks->get_addable_blocks();
2275      if (empty($missingblocks)) {
2276          $bc->content = get_string('noblockstoaddhere');
2277          return $bc;
2278      }
2279  
2280      $menu = array();
2281      foreach ($missingblocks as $block) {
2282          $menu[$block->name] = $block->title;
2283      }
2284  
2285      $actionurl = new moodle_url($page->url, array('sesskey'=>sesskey()));
2286      $select = new single_select($actionurl, 'bui_addblock', $menu, null, array(''=>get_string('adddots')), 'add_block');
2287      $select->set_label(get_string('addblock'), array('class'=>'accesshide'));
2288      $bc->content = $OUTPUT->render($select);
2289      return $bc;
2290  }
2291  
2292  /**
2293   * Actually delete from the database any blocks that are currently on this page,
2294   * but which should not be there according to blocks_name_allowed_in_format.
2295   *
2296   * @todo Write/Fix this function. Currently returns immediately
2297   * @param $course
2298   */
2299  function blocks_remove_inappropriate($course) {
2300      // TODO
2301      return;
2302      /*
2303      $blockmanager = blocks_get_by_page($page);
2304  
2305      if (empty($blockmanager)) {
2306          return;
2307      }
2308  
2309      if (($pageformat = $page->pagetype) == NULL) {
2310          return;
2311      }
2312  
2313      foreach($blockmanager as $region) {
2314          foreach($region as $instance) {
2315              $block = blocks_get_record($instance->blockid);
2316              if(!blocks_name_allowed_in_format($block->name, $pageformat)) {
2317                 blocks_delete_instance($instance->instance);
2318              }
2319          }
2320      }*/
2321  }
2322  
2323  /**
2324   * Check that a given name is in a permittable format
2325   *
2326   * @param string $name
2327   * @param string $pageformat
2328   * @return bool
2329   */
2330  function blocks_name_allowed_in_format($name, $pageformat) {
2331      $accept = NULL;
2332      $maxdepth = -1;
2333      if (!$bi = block_instance($name)) {
2334          return false;
2335      }
2336  
2337      $formats = $bi->applicable_formats();
2338      if (!$formats) {
2339          $formats = array();
2340      }
2341      foreach ($formats as $format => $allowed) {
2342          $formatregex = '/^'.str_replace('*', '[^-]*', $format).'.*$/';
2343          $depth = substr_count($format, '-');
2344          if (preg_match($formatregex, $pageformat) && $depth > $maxdepth) {
2345              $maxdepth = $depth;
2346              $accept = $allowed;
2347          }
2348      }
2349      if ($accept === NULL) {
2350          $accept = !empty($formats['all']);
2351      }
2352      return $accept;
2353  }
2354  
2355  /**
2356   * Delete a block, and associated data.
2357   *
2358   * @param object $instance a row from the block_instances table
2359   * @param bool $nolongerused legacy parameter. Not used, but kept for backwards compatibility.
2360   * @param bool $skipblockstables for internal use only. Makes @see blocks_delete_all_for_context() more efficient.
2361   */
2362  function blocks_delete_instance($instance, $nolongerused = false, $skipblockstables = false) {
2363      global $DB;
2364  
2365      // Allow plugins to use this block before we completely delete it.
2366      if ($pluginsfunction = get_plugins_with_function('pre_block_delete')) {
2367          foreach ($pluginsfunction as $plugintype => $plugins) {
2368              foreach ($plugins as $pluginfunction) {
2369                  $pluginfunction($instance);
2370              }
2371          }
2372      }
2373  
2374      if ($block = block_instance($instance->blockname, $instance)) {
2375          $block->instance_delete();
2376      }
2377      context_helper::delete_instance(CONTEXT_BLOCK, $instance->id);
2378  
2379      if (!$skipblockstables) {
2380          $DB->delete_records('block_positions', array('blockinstanceid' => $instance->id));
2381          $DB->delete_records('block_instances', array('id' => $instance->id));
2382          $DB->delete_records_list('user_preferences', 'name', array('block'.$instance->id.'hidden','docked_block_instance_'.$instance->id));
2383      }
2384  }
2385  
2386  /**
2387   * Delete multiple blocks at once.
2388   *
2389   * @param array $instanceids A list of block instance ID.
2390   */
2391  function blocks_delete_instances($instanceids) {
2392      global $DB;
2393  
2394      $limit = 1000;
2395      $count = count($instanceids);
2396      $chunks = [$instanceids];
2397      if ($count > $limit) {
2398          $chunks = array_chunk($instanceids, $limit);
2399      }
2400  
2401      // Perform deletion for each chunk.
2402      foreach ($chunks as $chunk) {
2403          $instances = $DB->get_recordset_list('block_instances', 'id', $chunk);
2404          foreach ($instances as $instance) {
2405              blocks_delete_instance($instance, false, true);
2406          }
2407          $instances->close();
2408  
2409          $DB->delete_records_list('block_positions', 'blockinstanceid', $chunk);
2410          $DB->delete_records_list('block_instances', 'id', $chunk);
2411  
2412          $preferences = array();
2413          foreach ($chunk as $instanceid) {
2414              $preferences[] = 'block' . $instanceid . 'hidden';
2415              $preferences[] = 'docked_block_instance_' . $instanceid;
2416          }
2417          $DB->delete_records_list('user_preferences', 'name', $preferences);
2418      }
2419  }
2420  
2421  /**
2422   * Delete all the blocks that belong to a particular context.
2423   *
2424   * @param int $contextid the context id.
2425   */
2426  function blocks_delete_all_for_context($contextid) {
2427      global $DB;
2428      $instances = $DB->get_recordset('block_instances', array('parentcontextid' => $contextid));
2429      foreach ($instances as $instance) {
2430          blocks_delete_instance($instance, true);
2431      }
2432      $instances->close();
2433      $DB->delete_records('block_instances', array('parentcontextid' => $contextid));
2434      $DB->delete_records('block_positions', array('contextid' => $contextid));
2435  }
2436  
2437  /**
2438   * Set a block to be visible or hidden on a particular page.
2439   *
2440   * @param object $instance a row from the block_instances, preferably LEFT JOINed with the
2441   *      block_positions table as return by block_manager.
2442   * @param moodle_page $page the back to set the visibility with respect to.
2443   * @param integer $newvisibility 1 for visible, 0 for hidden.
2444   */
2445  function blocks_set_visibility($instance, $page, $newvisibility) {
2446      global $DB;
2447      if (!empty($instance->blockpositionid)) {
2448          // Already have local information on this page.
2449          $DB->set_field('block_positions', 'visible', $newvisibility, array('id' => $instance->blockpositionid));
2450          return;
2451      }
2452  
2453      // Create a new block_positions record.
2454      $bp = new stdClass;
2455      $bp->blockinstanceid = $instance->id;
2456      $bp->contextid = $page->context->id;
2457      $bp->pagetype = $page->pagetype;
2458      if ($page->subpage) {
2459          $bp->subpage = $page->subpage;
2460      }
2461      $bp->visible = $newvisibility;
2462      $bp->region = $instance->defaultregion;
2463      $bp->weight = $instance->defaultweight;
2464      $DB->insert_record('block_positions', $bp);
2465  }
2466  
2467  /**
2468   * Get the block record for a particular blockid - that is, a particular type os block.
2469   *
2470   * @param $int blockid block type id. If null, an array of all block types is returned.
2471   * @param bool $notusedanymore No longer used.
2472   * @return array|object row from block table, or all rows.
2473   */
2474  function blocks_get_record($blockid = NULL, $notusedanymore = false) {
2475      global $PAGE;
2476      $blocks = $PAGE->blocks->get_installed_blocks();
2477      if ($blockid === NULL) {
2478          return $blocks;
2479      } else if (isset($blocks[$blockid])) {
2480          return $blocks[$blockid];
2481      } else {
2482          return false;
2483      }
2484  }
2485  
2486  /**
2487   * Find a given block by its blockid within a provide array
2488   *
2489   * @param int $blockid
2490   * @param array $blocksarray
2491   * @return bool|object Instance if found else false
2492   */
2493  function blocks_find_block($blockid, $blocksarray) {
2494      if (empty($blocksarray)) {
2495          return false;
2496      }
2497      foreach($blocksarray as $blockgroup) {
2498          if (empty($blockgroup)) {
2499              continue;
2500          }
2501          foreach($blockgroup as $instance) {
2502              if($instance->blockid == $blockid) {
2503                  return $instance;
2504              }
2505          }
2506      }
2507      return false;
2508  }
2509  
2510  // Functions for programatically adding default blocks to pages ================
2511  
2512   /**
2513    * Parse a list of default blocks. See config-dist for a description of the format.
2514    *
2515    * @param string $blocksstr Determines the starting point that the blocks are added in the region.
2516    * @return array the parsed list of default blocks
2517    */
2518  function blocks_parse_default_blocks_list($blocksstr) {
2519      $blocks = array();
2520      $bits = explode(':', $blocksstr);
2521      if (!empty($bits)) {
2522          $leftbits = trim(array_shift($bits));
2523          if ($leftbits != '') {
2524              $blocks[BLOCK_POS_LEFT] = explode(',', $leftbits);
2525          }
2526      }
2527      if (!empty($bits)) {
2528          $rightbits = trim(array_shift($bits));
2529          if ($rightbits != '') {
2530              $blocks[BLOCK_POS_RIGHT] = explode(',', $rightbits);
2531          }
2532      }
2533      return $blocks;
2534  }
2535  
2536  /**
2537   * @return array the blocks that should be added to the site course by default.
2538   */
2539  function blocks_get_default_site_course_blocks() {
2540      global $CFG;
2541  
2542      if (isset($CFG->defaultblocks_site)) {
2543          return blocks_parse_default_blocks_list($CFG->defaultblocks_site);
2544      } else {
2545          return array(
2546              BLOCK_POS_LEFT => array(),
2547              BLOCK_POS_RIGHT => array()
2548          );
2549      }
2550  }
2551  
2552  /**
2553   * Add the default blocks to a course.
2554   *
2555   * @param object $course a course object.
2556   */
2557  function blocks_add_default_course_blocks($course) {
2558      global $CFG;
2559  
2560      if (isset($CFG->defaultblocks_override)) {
2561          $blocknames = blocks_parse_default_blocks_list($CFG->defaultblocks_override);
2562  
2563      } else if ($course->id == SITEID) {
2564          $blocknames = blocks_get_default_site_course_blocks();
2565  
2566      } else if (isset($CFG->{'defaultblocks_' . $course->format})) {
2567          $blocknames = blocks_parse_default_blocks_list($CFG->{'defaultblocks_' . $course->format});
2568  
2569      } else {
2570          require_once($CFG->dirroot. '/course/lib.php');
2571          $blocknames = course_get_format($course)->get_default_blocks();
2572  
2573      }
2574  
2575      if ($course->id == SITEID) {
2576          $pagetypepattern = 'site-index';
2577      } else {
2578          $pagetypepattern = 'course-view-*';
2579      }
2580      $page = new moodle_page();
2581      $page->set_course($course);
2582      $page->blocks->add_blocks($blocknames, $pagetypepattern);
2583  }
2584  
2585  /**
2586   * Add the default system-context blocks. E.g. the admin tree.
2587   */
2588  function blocks_add_default_system_blocks() {
2589      global $DB;
2590  
2591      $page = new moodle_page();
2592      $page->set_context(context_system::instance());
2593      // We don't add blocks required by the theme, they will be auto-created.
2594      $page->blocks->add_blocks(array(BLOCK_POS_LEFT => array('admin_bookmarks')), 'admin-*', null, null, 2);
2595  
2596      if ($defaultmypage = $DB->get_record('my_pages', array('userid' => null, 'name' => '__default', 'private' => 1))) {
2597          $subpagepattern = $defaultmypage->id;
2598      } else {
2599          $subpagepattern = null;
2600      }
2601  
2602      $newblocks = array('timeline', 'private_files', 'online_users', 'badges', 'calendar_month', 'calendar_upcoming');
2603      $newcontent = array('lp', 'recentlyaccessedcourses', 'myoverview');
2604      $page->blocks->add_blocks(array(BLOCK_POS_RIGHT => $newblocks, 'content' => $newcontent), 'my-index', $subpagepattern);
2605  }