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

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Date condition.
  19   *
  20   * @package availability_date
  21   * @copyright 2014 The Open University
  22   * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace availability_date;
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  /**
  30   * Date condition.
  31   *
  32   * @package availability_date
  33   * @copyright 2014 The Open University
  34   * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  35   */
  36  class condition extends \core_availability\condition {
  37      /** @var string Availabile only from specified date. */
  38      const DIRECTION_FROM = '>=';
  39  
  40      /** @var string Availabile only until specified date. */
  41      const DIRECTION_UNTIL = '<';
  42  
  43      /** @var string One of the DIRECTION_xx constants. */
  44      private $direction;
  45  
  46      /** @var int Time (Unix epoch seconds) for condition. */
  47      private $time;
  48  
  49      /** @var int Forced current time (for unit tests) or 0 for normal. */
  50      private static $forcecurrenttime = 0;
  51  
  52      /**
  53       * Constructor.
  54       *
  55       * @param \stdClass $structure Data structure from JSON decode
  56       * @throws \coding_exception If invalid data structure.
  57       */
  58      public function __construct($structure) {
  59          // Get direction.
  60          if (isset($structure->d) && in_array($structure->d,
  61                  array(self::DIRECTION_FROM, self::DIRECTION_UNTIL))) {
  62              $this->direction = $structure->d;
  63          } else {
  64              throw new \coding_exception('Missing or invalid ->d for date condition');
  65          }
  66  
  67          // Get time.
  68          if (isset($structure->t) && is_int($structure->t)) {
  69              $this->time = $structure->t;
  70          } else {
  71              throw new \coding_exception('Missing or invalid ->t for date condition');
  72          }
  73      }
  74  
  75      public function save() {
  76          return (object)array('type' => 'date',
  77                  'd' => $this->direction, 't' => $this->time);
  78      }
  79  
  80      /**
  81       * Returns a JSON object which corresponds to a condition of this type.
  82       *
  83       * Intended for unit testing, as normally the JSON values are constructed
  84       * by JavaScript code.
  85       *
  86       * @param string $direction DIRECTION_xx constant
  87       * @param int $time Time in epoch seconds
  88       * @return stdClass Object representing condition
  89       */
  90      public static function get_json($direction, $time) {
  91          return (object)array('type' => 'date', 'd' => $direction, 't' => (int)$time);
  92      }
  93  
  94      public function is_available($not, \core_availability\info $info, $grabthelot, $userid) {
  95          return $this->is_available_for_all($not);
  96      }
  97  
  98      public function is_available_for_all($not = false) {
  99          // Check condition.
 100          $now = self::get_time();
 101          switch ($this->direction) {
 102              case self::DIRECTION_FROM:
 103                  $allow = $now >= $this->time;
 104                  break;
 105              case self::DIRECTION_UNTIL:
 106                  $allow = $now < $this->time;
 107                  break;
 108              default:
 109                  throw new \coding_exception('Unexpected direction');
 110          }
 111          if ($not) {
 112              $allow = !$allow;
 113          }
 114  
 115          return $allow;
 116      }
 117  
 118      /**
 119       * Obtains the actual direction of checking based on the $not value.
 120       *
 121       * @param bool $not True if condition is negated
 122       * @return string Direction constant
 123       * @throws \coding_exception
 124       */
 125      protected function get_logical_direction($not) {
 126          switch ($this->direction) {
 127              case self::DIRECTION_FROM:
 128                  return $not ? self::DIRECTION_UNTIL : self::DIRECTION_FROM;
 129              case self::DIRECTION_UNTIL:
 130                  return $not ? self::DIRECTION_FROM : self::DIRECTION_UNTIL;
 131              default:
 132                  throw new \coding_exception('Unexpected direction');
 133          }
 134      }
 135  
 136      public function get_description($full, $not, \core_availability\info $info) {
 137          return $this->get_either_description($not, false);
 138      }
 139  
 140      public function get_standalone_description(
 141              $full, $not, \core_availability\info $info) {
 142          return $this->get_either_description($not, true);
 143      }
 144  
 145      /**
 146       * Shows the description using the different lang strings for the standalone
 147       * version or the full one.
 148       *
 149       * @param bool $not True if NOT is in force
 150       * @param bool $standalone True to use standalone lang strings
 151       */
 152      protected function get_either_description($not, $standalone) {
 153          $direction = $this->get_logical_direction($not);
 154          $midnight = self::is_midnight($this->time);
 155          $midnighttag = $midnight ? '_date' : '';
 156          $satag = $standalone ? 'short_' : 'full_';
 157          switch ($direction) {
 158              case self::DIRECTION_FROM:
 159                  return get_string($satag . 'from' . $midnighttag, 'availability_date',
 160                          self::show_time($this->time, $midnight, false));
 161              case self::DIRECTION_UNTIL:
 162                  return get_string($satag . 'until' . $midnighttag, 'availability_date',
 163                          self::show_time($this->time, $midnight, true));
 164          }
 165      }
 166  
 167      protected function get_debug_string() {
 168          return $this->direction . ' ' . gmdate('Y-m-d H:i:s', $this->time);
 169      }
 170  
 171      /**
 172       * Gets time. This function is implemented here rather than calling time()
 173       * so that it can be overridden in unit tests. (Would really be nice if
 174       * Moodle had a generic way of doing that, but it doesn't.)
 175       *
 176       * @return int Current time (seconds since epoch)
 177       */
 178      protected static function get_time() {
 179          if (self::$forcecurrenttime) {
 180              return self::$forcecurrenttime;
 181          } else {
 182              return time();
 183          }
 184      }
 185  
 186      /**
 187       * Forces the current time for unit tests.
 188       *
 189       * @param int $forcetime Time to return from the get_time function
 190       */
 191      public static function set_current_time_for_test($forcetime = 0) {
 192          self::$forcecurrenttime = $forcetime;
 193      }
 194  
 195      /**
 196       * Shows a time either as a date or a full date and time, according to
 197       * user's timezone.
 198       *
 199       * @param int $time Time
 200       * @param bool $dateonly If true, uses date only
 201       * @param bool $until If true, and if using date only, shows previous date
 202       * @return string Date
 203       */
 204      protected function show_time($time, $dateonly, $until = false) {
 205          // For 'until' dates that are at midnight, e.g. midnight 5 March, it
 206          // is better to word the text as 'until end 4 March'.
 207          $daybefore = false;
 208          if ($until && $dateonly) {
 209              $daybefore = true;
 210              $time = strtotime('-1 day', $time);
 211          }
 212          return userdate($time,
 213                  get_string($dateonly ? 'strftimedate' : 'strftimedatetime', 'langconfig'));
 214      }
 215  
 216      /**
 217       * Checks whether a given time refers exactly to midnight (in current user
 218       * timezone).
 219       *
 220       * @param int $time Time
 221       * @return bool True if time refers to midnight, false otherwise
 222       */
 223      protected static function is_midnight($time) {
 224          return usergetmidnight($time) == $time;
 225      }
 226  
 227      public function update_after_restore(
 228              $restoreid, $courseid, \base_logger $logger, $name) {
 229          // Update the date, if restoring with changed date.
 230          $dateoffset = \core_availability\info::get_restore_date_offset($restoreid);
 231          if ($dateoffset) {
 232              $this->time += $dateoffset;
 233              return true;
 234          }
 235          return false;
 236      }
 237  
 238      /**
 239       * Changes all date restrictions on a course by the specified shift amount.
 240       * Used by the course reset feature.
 241       *
 242       * @param int $courseid Course id
 243       * @param int $timeshift Offset in seconds
 244       */
 245      public static function update_all_dates($courseid, $timeshift) {
 246          global $DB;
 247  
 248          $modinfo = get_fast_modinfo($courseid);
 249          $anychanged = false;
 250  
 251          // Adjust dates from all course modules.
 252          foreach ($modinfo->cms as $cm) {
 253              if (!$cm->availability) {
 254                  continue;
 255              }
 256              $info = new \core_availability\info_module($cm);
 257              $tree = $info->get_availability_tree();
 258              $dates = $tree->get_all_children('availability_date\condition');
 259              $changed = false;
 260              foreach ($dates as $date) {
 261                  $date->time += $timeshift;
 262                  $changed = true;
 263              }
 264  
 265              // Save the updated course module.
 266              if ($changed) {
 267                  $DB->set_field('course_modules', 'availability', json_encode($tree->save()),
 268                          array('id' => $cm->id));
 269                  $anychanged = true;
 270              }
 271          }
 272  
 273          // Adjust dates from all course sections.
 274          foreach ($modinfo->get_section_info_all() as $section) {
 275              if (!$section->availability) {
 276                  continue;
 277              }
 278  
 279              $info = new \core_availability\info_section($section);
 280              $tree = $info->get_availability_tree();
 281              $dates = $tree->get_all_children('availability_date\condition');
 282              $changed = false;
 283              foreach ($dates as $date) {
 284                  $date->time += $timeshift;
 285                  $changed = true;
 286              }
 287  
 288              // Save the updated course module.
 289              if ($changed) {
 290                  $updatesection = new \stdClass();
 291                  $updatesection->id = $section->id;
 292                  $updatesection->availability = json_encode($tree->save());
 293                  $updatesection->timemodified = time();
 294                  $DB->update_record('course_sections', $updatesection);
 295                  // Invalidate the section cache by given section id.
 296                  \course_modinfo::purge_course_section_cache_by_id($courseid, $section->id);
 297  
 298                  $anychanged = true;
 299              }
 300          }
 301  
 302          if ($anychanged) {
 303              // Partial rebuild the sections which have been invalidated.
 304              rebuild_course_cache($courseid, true, true);
 305          }
 306      }
 307  }