C:/xampp/htdocs/moodle/lib/modinfolib.php

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<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

// Maximum number of modinfo items to keep in memory cache. Do not increase this to a large
// number because:
// a) modinfo can be big (megabyte range) for some courses
// b) performance of cache will deteriorate if there are very many items in it
if (!defined('MAX_MODINFO_CACHE_SIZE')) {
    define('MAX_MODINFO_CACHE_SIZE', 10);
}


class course_modinfo extends stdClass {
    // For convenience we store the course object here as it is needed in other parts of code
    private $course;

    // Existing data fields

    // These are public for backward compatibility. Note: it is not possible to retain BC
    // using PHP magic get methods because behaviour is different with regard to empty().

    public $courseid;

    public $userid;

    public $sections;

    public $cms;

    public $instances;

    public $groups;

    // Get methods for data

    public function get_course() {
        return $this->course;
    }

    public function get_course_id() {
        return $this->courseid;
    }

    public function get_user_id() {
        return $this->userid;
    }

    public function get_sections() {
        return $this->sections;
    }

    public function get_cms() {
        return $this->cms;
    }

    public function get_cm($cmid) {
        if (empty($this->cms[$cmid])) {
            throw new moodle_exception('invalidcoursemodule', 'error');
        }
        return $this->cms[$cmid];
    }

    public function get_instances() {
        return $this->instances;
    }

    public function get_instances_of($modname) {
        if (empty($this->instances[$modname])) {
            return array();
        }
        return $this->instances[$modname];
    }

    public function get_groups($groupingid=0) {
        if (is_null($this->groups)) {
            // NOTE: Performance could be improved here. The system caches user groups
            // in $USER->groupmember[$courseid] => array of groupid=>groupid. Unfortunately this
            // structure does not include grouping information. It probably could be changed to
            // do so, without a significant performance hit on login, thus saving this one query
            // each request.
            $this->groups = groups_get_user_groups($this->courseid, $this->userid);
        }
        if (!isset($this->groups[$groupingid])) {
            return array();
        }
        return $this->groups[$groupingid];
    }

    public function __construct($course, $userid) {
        global $CFG, $DB;

        // Set initial values
        $this->courseid = $course->id;
        $this->userid = $userid;
        $this->sections = array();
        $this->cms = array();
        $this->instances = array();
        $this->groups = null;
        $this->course = $course;

        // Check modinfo field is set. If not, build and load it.
        if (empty($course->modinfo)) {
            rebuild_course_cache($course->id);
            $course->modinfo = $DB->get_field('course', 'modinfo', array('id'=>$course->id));
        }

        // Load modinfo field into memory as PHP object and check it's valid
        $info = unserialize($course->modinfo);
        if (!is_array($info)) {
            // hmm, something is wrong - lets try to fix it
            rebuild_course_cache($course->id);
            $course->modinfo = $DB->get_field('course', 'modinfo', array('id'=>$course->id));
            $info = unserialize($course->modinfo);
            if (!is_array($info)) {
                // If it still fails, abort
                debugging('Problem with "modinfo" data for this course');
                return;
            }
        }

        // If we haven't already preloaded contexts for the course, do it now
        preload_course_contexts($course->id);

        // Loop through each piece of module data, constructing it
        $modexists = array();
        foreach ($info as $mod) {
            if (empty($mod->name)) {
                // something is wrong here
                continue;
            }

            // Skip modules which don't exist
            if (empty($modexists[$mod->mod])) {
                if (!file_exists("$CFG->dirroot/mod/$mod->mod/lib.php")) {
                    continue;
                }
                $modexists[$mod->mod] = true;
            }

            // Construct info for this module
            $cm = new cm_info($this, $course, $mod, $info);

            // Store module in instances and cms array
            if (!isset($this->instances[$cm->modname])) {
                $this->instances[$cm->modname] = array();
            }
            $this->instances[$cm->modname][$cm->instance] = $cm;
            $this->cms[$cm->id] = $cm;

            // Reconstruct sections. This works because modules are stored in order
            if (!isset($this->sections[$cm->sectionnum])) {
                $this->sections[$cm->sectionnum] = array();
            }
            $this->sections[$cm->sectionnum][] = $cm->id;
        }

        // We need at least 'dynamic' data from each course-module (this is basically the remaining
        // data which was always present in previous version of get_fast_modinfo, so it's required
        // for BC). Creating it in a second pass is necessary because obtain_dynamic_data sometimes
        // needs to be able to refer to a 'complete' (with basic data) modinfo.
        foreach ($this->cms as $cm) {
            $cm->obtain_dynamic_data();
        }
    }
}


class cm_info extends stdClass  {
    const STATE_BASIC = 0;

    const STATE_DYNAMIC = 1;

    const STATE_VIEW = 2;

    private $modinfo;

    private $state;

    // Existing data fields

    public $id;

    public $instance;

    public $course;

    public $idnumber;

    public $added;

    public $score;

    public $visible;

    public $visibleold;

    public $groupmode;

    public $groupingid;

    public $groupmembersonly;

    public $indent;

    public $completion;

    public $completiongradeitemnumber;

    public $completionview;

    public $completionexpected;

    public $availablefrom;

    public $availableuntil;

    public $showavailability;

    public $showdescription;

    public $extra;

    public $icon;

    public $iconcomponent;

    public $modname;

    public $module;

    public $name;

    public $sectionnum;

    public $section;

    public $conditionscompletion;

    public $conditionsgrade;

    public $modplural;

    public $available;

    public $availableinfo;

    public $uservisible;

    public $context;


    // New data available only via functions

    private $url;

    private $content;

    private $extraclasses;

    private $iconurl;

    private $onclick;

    private $customdata;

    private $afterlink;

    private $afterediticons;

    public function has_view() {
        return !is_null($this->url);
    }

    public function get_url() {
        return $this->url;
    }

    public function get_content() {
        $this->obtain_view_data();
        return $this->content;
    }

    public function get_extra_classes() {
        $this->obtain_view_data();
        return $this->extraclasses;
    }

    public function get_on_click() {
        // Does not need view data; may be used by navigation
        return $this->onclick;
    }
    public function get_custom_data() {
        return $this->customdata;
    }

    public function get_after_link() {
        $this->obtain_view_data();
        return $this->afterlink;
    }

    public function get_after_edit_icons() {
        $this->obtain_view_data();
        return $this->afterediticons;
    }

    public function get_icon_url($output = null) {
        global $OUTPUT;
        if (!$output) {
            $output = $OUTPUT;
        }
        // Support modules setting their own, external, icon image
        if (!empty($this->iconurl)) {
            $icon = $this->iconurl;

        // Fallback to normal local icon + component procesing
        } else if (!empty($this->icon)) {
            if (substr($this->icon, 0, 4) === 'mod/') {
                list($modname, $iconname) = explode('/', substr($this->icon, 4), 2);
                $icon = $output->pix_url($iconname, $modname);
            } else {
                if (!empty($this->iconcomponent)) {
                    // Icon  has specified component
                    $icon = $output->pix_url($this->icon, $this->iconcomponent);
                } else {
                    // Icon does not have specified component, use default
                    $icon = $output->pix_url($this->icon);
                }
            }
        } else {
            $icon = $output->pix_url('icon', $this->modname);
        }
        return $icon;
    }

    public function get_modinfo() {
        return $this->modinfo;
    }

    public function get_course() {
        return $this->modinfo->get_course();
    }

    // Set functions

    public function set_content($content) {
        $this->content = $content;
    }

    public function set_extra_classes($extraclasses) {
        $this->extraclasses = $extraclasses;
    }

    public function set_icon_url(moodle_url $iconurl) {
        $this->iconurl = $iconurl;
    }

    public function set_on_click($onclick) {
        $this->check_not_view_only();
        $this->onclick = $onclick;
    }

    public function set_after_link($afterlink) {
        $this->afterlink = $afterlink;
    }

    public function set_after_edit_icons($afterediticons) {
        $this->afterediticons = $afterediticons;
    }

    public function set_name($name) {
        $this->update_user_visible();
        $this->name = $name;
    }

    public function set_no_view_link() {
        $this->check_not_view_only();
        $this->url = null;
    }

    public function set_user_visible($uservisible) {
        $this->check_not_view_only();
        $this->uservisible = $uservisible;
    }

    public function set_available($available, $showavailability=0, $availableinfo='') {
        $this->check_not_view_only();
        $this->available = $available;
        $this->showavailability = $showavailability;
        $this->availableinfo = $availableinfo;
        $this->update_user_visible();
    }

    private function check_not_view_only() {
        if ($this->state >= self::STATE_DYNAMIC) {
            throw new coding_exception('Cannot set this data from _cm_info_view because it may ' .
                    'affect other pages as well as view');
        }
    }

    public function __construct(course_modinfo $modinfo, $course, $mod, $info) {
        global $CFG;
        $this->modinfo = $modinfo;

        $this->id               = $mod->cm;
        $this->instance         = $mod->id;
        $this->course           = $course->id;
        $this->modname          = $mod->mod;
        $this->idnumber         = isset($mod->idnumber) ? $mod->idnumber : '';
        $this->name             = $mod->name;
        $this->visible          = $mod->visible;
        $this->sectionnum       = $mod->section; // Note weirdness with name here
        $this->groupmode        = isset($mod->groupmode) ? $mod->groupmode : 0;
        $this->groupingid       = isset($mod->groupingid) ? $mod->groupingid : 0;
        $this->groupmembersonly = isset($mod->groupmembersonly) ? $mod->groupmembersonly : 0;
        $this->indent           = isset($mod->indent) ? $mod->indent : 0;
        $this->extra            = isset($mod->extra) ? $mod->extra : '';
        $this->extraclasses     = isset($mod->extraclasses) ? $mod->extraclasses : '';
        $this->iconurl          = isset($mod->iconurl) ? $mod->iconurl : '';
        $this->onclick          = isset($mod->onclick) ? $mod->onclick : '';
        $this->content          = isset($mod->content) ? $mod->content : '';
        $this->icon             = isset($mod->icon) ? $mod->icon : '';
        $this->iconcomponent    = isset($mod->iconcomponent) ? $mod->iconcomponent : '';
        $this->customdata       = isset($mod->customdata) ? $mod->customdata : '';
        $this->context          = get_context_instance(CONTEXT_MODULE, $mod->cm);
        $this->showdescription  = isset($mod->showdescription) ? $mod->showdescription : 0;
        $this->state = self::STATE_BASIC;

        // This special case handles old label data. Labels used to use the 'name' field for
        // content
        if ($this->modname === 'label' && $this->content === '') {
            $this->content = $this->extra;
            $this->extra = '';
        }

        // Note: These fields from $cm were not present in cm_info in Moodle
        // 2.0.2 and prior. They may not be available if course cache hasn't
        // been rebuilt since then.
        $this->section = isset($mod->sectionid) ? $mod->sectionid : 0;
        $this->module = isset($mod->module) ? $mod->module : 0;
        $this->added = isset($mod->added) ? $mod->added : 0;
        $this->score = isset($mod->score) ? $mod->score : 0;
        $this->visibleold = isset($mod->visibleold) ? $mod->visibleold : 0;

        // Note: it saves effort and database space to always include the
        // availability and completion fields, even if availability or completion
        // are actually disabled
        $this->completion = isset($mod->completion) ? $mod->completion : 0;
        $this->completiongradeitemnumber = isset($mod->completiongradeitemnumber)
                ? $mod->completiongradeitemnumber : null;
        $this->completionview = isset($mod->completionview)
                ? $mod->completionview : 0;
        $this->completionexpected = isset($mod->completionexpected)
                ? $mod->completionexpected : 0;
        $this->showavailability = isset($mod->showavailability) ? $mod->showavailability : 0;
        $this->availablefrom = isset($mod->availablefrom) ? $mod->availablefrom : 0;
        $this->availableuntil = isset($mod->availableuntil) ? $mod->availableuntil : 0;
        $this->conditionscompletion = isset($mod->conditionscompletion)
                ? $mod->conditionscompletion : array();
        $this->conditionsgrade = isset($mod->conditionsgrade)
                ? $mod->conditionsgrade : array();

        // Get module plural name.
        // TODO This was a very old performance hack and should now be removed as the information
        // certainly doesn't belong in modinfo. On a 'normal' page this is only used in the
        // activity_modules block, so if it needs caching, it should be cached there.
        static $modplurals;
        if (!isset($modplurals[$this->modname])) {
            $modplurals[$this->modname] = get_string('modulenameplural', $this->modname);
        }
        $this->modplural = $modplurals[$this->modname];

        static $modviews;
        if (!isset($modviews[$this->modname])) {
            $modviews[$this->modname] = !plugin_supports('mod', $this->modname,
                    FEATURE_NO_VIEW_LINK);
        }
        $this->url = $modviews[$this->modname]
                ? new moodle_url('/mod/' . $this->modname . '/view.php', array('id'=>$this->id))
                : null;
    }

    public function obtain_dynamic_data() {
        global $CFG;
        if ($this->state >= self::STATE_DYNAMIC) {
            return;
        }
        $userid = $this->modinfo->get_user_id();

        if (!empty($CFG->enableavailability)) {
            // Get availability information
            $ci = new condition_info($this);
            // Note that the modinfo currently available only includes minimal details (basic data)
            // so passing it to this function is a bit dangerous as it would cause infinite
            // recursion if it tried to get dynamic data, however we know that this function only
            // uses basic data.
            $this->available = $ci->is_available($this->availableinfo, true,
                    $userid, $this->modinfo);
        } else {
            $this->available = true;
        }

        // Update visible state for current user
        $this->update_user_visible();

        // Let module make dynamic changes at this point
        $this->call_mod_function('cm_info_dynamic');
        $this->state = self::STATE_DYNAMIC;
    }

    private function update_user_visible() {
        global $CFG;
        $modcontext = get_context_instance(CONTEXT_MODULE, $this->id);
        $userid = $this->modinfo->get_user_id();
        $this->uservisible = true;
        if ((!$this->visible or !$this->available) and
                !has_capability('moodle/course:viewhiddenactivities', $modcontext, $userid)) {
            // If the activity is hidden or unavailable, and you don't have viewhiddenactivities,
            // set it so that user can't see or access it
            $this->uservisible = false;
        } else if (!empty($CFG->enablegroupmembersonly) and !empty($this->groupmembersonly)
                and !has_capability('moodle/site:accessallgroups', $modcontext, $userid)) {
            // If the activity has 'group members only' and you don't have accessallgroups...
            $groups = $this->modinfo->get_groups($this->groupingid);
            if (empty($groups)) {
                // ...and you don't belong to a group, then set it so you can't see/access it
                $this->uservisible = false;
            }
        }
    }

    private function call_mod_function($type) {
        global $CFG;
        $libfile = $CFG->dirroot . '/mod/' . $this->modname . '/lib.php';
        if (file_exists($libfile)) {
            include_once($libfile);
            $function = 'mod_' . $this->modname . '_' . $type;
            if (function_exists($function)) {
                $function($this);
            } else {
                $function = $this->modname . '_' . $type;
                if (function_exists($function)) {
                    $function($this);
                }
            }
        }
    }

    private function obtain_view_data() {
        if ($this->state >= self::STATE_VIEW) {
            return;
        }

        // Let module make changes at this point
        $this->call_mod_function('cm_info_view');
        $this->state = self::STATE_VIEW;
    }
}


function get_fast_modinfo(&$course, $userid=0) {
    global $CFG, $USER, $DB;
    require_once($CFG->dirroot.'/course/lib.php');

    if (!empty($CFG->enableavailability)) {
        require_once($CFG->libdir.'/conditionlib.php');
    }

    static $cache = array();

    if ($course === 'reset') {
        $cache = array();
        return null;
    }

    if (empty($userid)) {
        $userid = $USER->id;
    }

    if (array_key_exists($course->id, $cache) and $cache[$course->id]->userid == $userid) {
        return $cache[$course->id];
    }

    if (!property_exists($course, 'modinfo')) {
        debugging('Coding problem - missing course modinfo property in get_fast_modinfo() call');
    }

    unset($cache[$course->id]); // prevent potential reference problems when switching users

    $cache[$course->id] = new course_modinfo($course, $userid);

    // Ensure cache does not use too much RAM
    if (count($cache) > MAX_MODINFO_CACHE_SIZE) {
        reset($cache);
        $key = key($cache);
        unset($cache[$key]->instances);
        unset($cache[$key]->cms);
        unset($cache[$key]);
    }

    return $cache[$course->id];
}

function rebuild_course_cache($courseid=0, $clearonly=false) {
    global $COURSE, $DB, $CFG;

    // Destroy navigation caches
    navigation_cache::destroy_volatile_caches();

    if ($clearonly) {
        if (empty($courseid)) {
            $courseselect = array();
        } else {
            $courseselect = array('id'=>$courseid);
        }
        $DB->set_field('course', 'modinfo', null, $courseselect);
        // update cached global COURSE too ;-)
        if ($courseid == $COURSE->id or empty($courseid)) {
            $COURSE->modinfo = null;
        }
        // reset the fast modinfo cache
        $reset = 'reset';
        get_fast_modinfo($reset);
        return;
    }

    require_once("$CFG->dirroot/course/lib.php");

    if ($courseid) {
        $select = array('id'=>$courseid);
    } else {
        $select = array();
        @set_time_limit(0);  // this could take a while!   MDL-10954
    }

    $rs = $DB->get_recordset("course", $select,'','id,fullname');
    foreach ($rs as $course) {
        $modinfo = serialize(get_array_of_activities($course->id));
        $DB->set_field("course", "modinfo", $modinfo, array("id"=>$course->id));
        // update cached global COURSE too ;-)
        if ($course->id == $COURSE->id) {
            $COURSE->modinfo = $modinfo;
        }
    }
    $rs->close();
    // reset the fast modinfo cache
    $reset = 'reset';
    get_fast_modinfo($reset);
}


class cached_cm_info {
    public $name;

    public $icon;

    public $iconcomponent;

    public $content;

    public $customdata;

    public $extraclasses;

    public $iconurl;

    public $onclick;
}