diff --git a/course/view.php b/course/view.php
index ed3c46c61ba..e9ef5d730bc 100644
--- a/course/view.php
+++ b/course/view.php
@@ -1,314 +1,341 @@
 <?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/>.
 
-//  Display the course home page.
+/**
+ * Display the course home page.
+ *
+ * @copyright 1999 Martin Dougiamas  http://dougiamas.com
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core_course
+ */
 
-    require_once('../config.php');
-    require_once('lib.php');
-    require_once($CFG->libdir.'/completionlib.php');
+require_once('../config.php');
+require_once('lib.php');
+require_once($CFG->libdir.'/completionlib.php');
 
-    redirect_if_major_upgrade_required();
+redirect_if_major_upgrade_required();
 
-    $id          = optional_param('id', 0, PARAM_INT);
-    $name        = optional_param('name', '', PARAM_TEXT);
-    $edit        = optional_param('edit', -1, PARAM_BOOL);
-    $hide        = optional_param('hide', 0, PARAM_INT);
-    $show        = optional_param('show', 0, PARAM_INT);
-    $duplicatesection = optional_param('duplicatesection', 0, PARAM_INT);
-    $idnumber    = optional_param('idnumber', '', PARAM_RAW);
-    $sectionid   = optional_param('sectionid', 0, PARAM_INT);
-    $section     = optional_param('section', 0, PARAM_INT);
-    $expandsection = optional_param('expandsection', -1, PARAM_INT);
-    $move        = optional_param('move', 0, PARAM_INT);
-    $marker      = optional_param('marker',-1 , PARAM_INT);
-    $switchrole  = optional_param('switchrole',-1, PARAM_INT); // Deprecated, use course/switchrole.php instead.
-    $return      = optional_param('return', 0, PARAM_LOCALURL);
+$id = optional_param('id', 0, PARAM_INT);
+$name = optional_param('name', '', PARAM_TEXT);
+$edit = optional_param('edit', -1, PARAM_BOOL);
+$hide = optional_param('hide', 0, PARAM_INT);
+$show = optional_param('show', 0, PARAM_INT);
+$duplicatesection = optional_param('duplicatesection', 0, PARAM_INT);
+$idnumber = optional_param('idnumber', '', PARAM_RAW);
+$sectionid = optional_param('sectionid', 0, PARAM_INT);
+$section = optional_param('section', 0, PARAM_INT);
+$expandsection = optional_param('expandsection', -1, PARAM_INT);
+$move = optional_param('move', 0, PARAM_INT);
+$marker = optional_param('marker', -1 , PARAM_INT);
+$switchrole = optional_param('switchrole', -1, PARAM_INT); // Deprecated, use course/switchrole.php instead.
+$return = optional_param('return', 0, PARAM_LOCALURL);
 
-    $params = array();
-    if (!empty($name)) {
-        $params = array('shortname' => $name);
-    } else if (!empty($idnumber)) {
-        $params = array('idnumber' => $idnumber);
-    } else if (!empty($id)) {
-        $params = array('id' => $id);
-    }else {
-        throw new \moodle_exception('unspecifycourseid', 'error');
-    }
+$params = [];
+if (!empty($name)) {
+    $params = ['shortname' => $name];
+} else if (!empty($idnumber)) {
+    $params = ['idnumber' => $idnumber];
+} else if (!empty($id)) {
+    $params = ['id' => $id];
+} else {
+    throw new \moodle_exception('unspecifycourseid', 'error');
+}
 
-    $course = $DB->get_record('course', $params, '*', MUST_EXIST);
+$course = $DB->get_record('course', $params, '*', MUST_EXIST);
 
-    $urlparams = array('id' => $course->id);
+$urlparams = ['id' => $course->id];
 
-    // Sectionid should get priority over section number
-    if ($sectionid) {
-        $section = $DB->get_field('course_sections', 'section', array('id' => $sectionid, 'course' => $course->id), MUST_EXIST);
-    }
-    if ($section) {
-        $urlparams['section'] = $section;
-    }
-    if ($expandsection !== -1) {
-        $urlparams['expandsection'] = $expandsection;
-    }
+// Sectionid should get priority over section number.
+if ($sectionid) {
+    $section = $DB->get_field('course_sections', 'section', ['id' => $sectionid, 'course' => $course->id], MUST_EXIST);
+}
+if ($section) {
+    $urlparams['section'] = $section;
+}
+if ($expandsection !== -1) {
+    $urlparams['expandsection'] = $expandsection;
+}
 
-    $PAGE->set_url('/course/view.php', $urlparams); // Defined here to avoid notices on errors etc
+$PAGE->set_url('/course/view.php', $urlparams); // Defined here to avoid notices on errors etc.
 
-    // Prevent caching of this page to stop confusion when changing page after making AJAX changes
-    $PAGE->set_cacheable(false);
+// Prevent caching of this page to stop confusion when changing page after making AJAX changes.
+$PAGE->set_cacheable(false);
 
-    context_helper::preload_course($course->id);
-    $context = context_course::instance($course->id, MUST_EXIST);
+context_helper::preload_course($course->id);
+$context = context_course::instance($course->id, MUST_EXIST);
 
-    // Remove any switched roles before checking login
-    if ($switchrole == 0 && confirm_sesskey()) {
+// Remove any switched roles before checking login.
+if ($switchrole == 0 && confirm_sesskey()) {
+    role_switch($switchrole, $context);
+}
+
+require_login($course);
+
+// Switchrole - sanity check in cost-order...
+$resetuserallowedediting = false;
+if ($switchrole > 0 && confirm_sesskey() &&
+    has_capability('moodle/role:switchroles', $context)) {
+    // Is this role assignable in this context?
+    // Inquiring minds want to know.
+    $aroles = get_switchable_roles($context);
+    if (is_array($aroles) && isset($aroles[$switchrole])) {
         role_switch($switchrole, $context);
+        // Double check that this role is allowed here.
+        require_login($course);
     }
+    // Reset course page state. This prevents some weird problems.
+    $USER->activitycopy = false;
+    $USER->activitycopycourse = null;
+    unset($USER->activitycopyname);
+    unset($SESSION->modform);
+    $USER->editing = 0;
+    $resetuserallowedediting = true;
+}
 
-    require_login($course);
-
-    // Switchrole - sanity check in cost-order...
-    $reset_user_allowed_editing = false;
-    if ($switchrole > 0 && confirm_sesskey() &&
-        has_capability('moodle/role:switchroles', $context)) {
-        // is this role assignable in this context?
-        // inquiring minds want to know...
-        $aroles = get_switchable_roles($context);
-        if (is_array($aroles) && isset($aroles[$switchrole])) {
-            role_switch($switchrole, $context);
-            // Double check that this role is allowed here
-            require_login($course);
-        }
-        // reset course page state - this prevents some weird problems ;-)
-        $USER->activitycopy = false;
-        $USER->activitycopycourse = NULL;
-        unset($USER->activitycopyname);
-        unset($SESSION->modform);
-        $USER->editing = 0;
-        $reset_user_allowed_editing = true;
-    }
-
-    //If course is hosted on an external server, redirect to corresponding
-    //url with appropriate authentication attached as parameter
-    if (file_exists($CFG->dirroot .'/course/externservercourse.php')) {
-        include $CFG->dirroot .'/course/externservercourse.php';
-        if (function_exists('extern_server_course')) {
-            if ($extern_url = extern_server_course($course)) {
-                redirect($extern_url);
-            }
+// If course is hosted on an external server, redirect to corresponding
+// url with appropriate authentication attached as parameter.
+if (file_exists($CFG->dirroot . '/course/externservercourse.php')) {
+    include($CFG->dirroot . '/course/externservercourse.php');
+    if (function_exists('extern_server_course')) {
+        if ($externurl = extern_server_course($course)) {
+            redirect($externurl);
         }
     }
+}
 
+require_once($CFG->dirroot.'/calendar/lib.php'); // This is after login because it needs $USER.
 
-    require_once($CFG->dirroot.'/calendar/lib.php');    /// This is after login because it needs $USER
+// Must set layout before gettting section info. See MDL-47555.
+$PAGE->set_pagelayout('course');
+$PAGE->add_body_class('limitedwidth');
 
-    // Must set layout before gettting section info. See MDL-47555.
-    $PAGE->set_pagelayout('course');
-    $PAGE->add_body_class('limitedwidth');
+if ($section && $section > 0) {
 
-    if ($section and $section > 0) {
-
-        // Get section details and check it exists.
-        $modinfo = get_fast_modinfo($course);
-        $coursesections = $modinfo->get_section_info($section, MUST_EXIST);
-
-        // Check user is allowed to see it.
-        if (!$coursesections->uservisible) {
-            // Check if coursesection has conditions affecting availability and if
-            // so, output availability info.
-            if ($coursesections->visible && $coursesections->availableinfo) {
-                $sectionname     = get_section_name($course, $coursesections);
-                $message = get_string('notavailablecourse', '', $sectionname);
-                redirect(course_get_url($course), $message, null, \core\output\notification::NOTIFY_ERROR);
-            } else {
-                // Note: We actually already know they don't have this capability
-                // or uservisible would have been true; this is just to get the
-                // correct error message shown.
-                require_capability('moodle/course:viewhiddensections', $context);
-            }
-        }
-    }
-
-    // Fix course format if it is no longer installed
-    $format = course_get_format($course);
-    $course->format = $format->get_format();
-
-    $PAGE->set_pagetype('course-view-' . $course->format);
-    $PAGE->set_other_editing_capability('moodle/course:update');
-    $PAGE->set_other_editing_capability('moodle/course:manageactivities');
-    $PAGE->set_other_editing_capability('moodle/course:activityvisibility');
-    if (course_format_uses_sections($course->format)) {
-        $PAGE->set_other_editing_capability('moodle/course:sectionvisibility');
-        $PAGE->set_other_editing_capability('moodle/course:movesections');
-    }
-
-    // Preload course format renderer before output starts.
-    // This is a little hacky but necessary since
-    // format.php is not included until after output starts
-    $renderer = $format->get_renderer($PAGE);
-
-    if ($reset_user_allowed_editing) {
-        // ugly hack
-        unset($PAGE->_user_allowed_editing);
-    }
-
-    if (!isset($USER->editing)) {
-        $USER->editing = 0;
-    }
-    if ($PAGE->user_allowed_editing()) {
-        if (($edit == 1) and confirm_sesskey()) {
-            $USER->editing = 1;
-            // Redirect to site root if Editing is toggled on frontpage
-            if ($course->id == SITEID) {
-                redirect($CFG->wwwroot .'/?redirect=0');
-            } else if (!empty($return)) {
-                redirect($CFG->wwwroot . $return);
-            } else {
-                $url = new moodle_url($PAGE->url, array('notifyeditingon' => 1));
-                redirect($url);
-            }
-        } else if (($edit == 0) and confirm_sesskey()) {
-            $USER->editing = 0;
-            if(!empty($USER->activitycopy) && $USER->activitycopycourse == $course->id) {
-                $USER->activitycopy       = false;
-                $USER->activitycopycourse = NULL;
-            }
-            // Redirect to site root if Editing is toggled on frontpage
-            if ($course->id == SITEID) {
-                redirect($CFG->wwwroot .'/?redirect=0');
-            } else if (!empty($return)) {
-                redirect($CFG->wwwroot . $return);
-            } else {
-                redirect($PAGE->url);
-            }
-        }
-
-        if (has_capability('moodle/course:sectionvisibility', $context)) {
-            if ($hide && confirm_sesskey()) {
-                set_section_visible($course->id, $hide, '0');
-                redirect($PAGE->url);
-            }
-
-            if ($show && confirm_sesskey()) {
-                set_section_visible($course->id, $show, '1');
-                redirect($PAGE->url);
-            }
-        }
-
-        if (!empty($section) && !empty($coursesections) && !empty($duplicatesection)
-            && has_capability('moodle/course:update', $context) && confirm_sesskey()) {
-            $newsection = $format->duplicate_section($coursesections);
-            redirect(course_get_url($course, $newsection->section));
-        }
-
-        if (!empty($section) && !empty($move) &&
-                has_capability('moodle/course:movesections', $context) && confirm_sesskey()) {
-            $destsection = $section + $move;
-            if (move_section_to($course, $section, $destsection)) {
-                if ($course->id == SITEID) {
-                    redirect($CFG->wwwroot . '/?redirect=0');
-                } else {
-                    if ($format->get_course_display() == COURSE_DISPLAY_MULTIPAGE) {
-                        redirect(course_get_url($course));
-                    } else {
-                        redirect(course_get_url($course, $destsection));
-                    }
-                }
-            } else {
-                echo $OUTPUT->notification('An error occurred while moving a section');
-            }
-        }
-    } else {
-        $USER->editing = 0;
-    }
-
-    $SESSION->fromdiscussion = $PAGE->url->out(false);
-
-
-    if ($course->id == SITEID) {
-        // This course is not a real course.
-        redirect($CFG->wwwroot .'/?redirect=0');
-    }
-
-    // Determine whether the user has permission to download course content.
-    $candownloadcourse = \core\content::can_export_context($context, $USER);
-
-    // We are currently keeping the button here from 1.x to help new teachers figure out
-    // what to do, even though the link also appears in the course admin block.  It also
-    // means you can back out of a situation where you removed the admin block. :)
-    if ($PAGE->user_allowed_editing()) {
-        $buttons = $OUTPUT->edit_button($PAGE->url);
-        $PAGE->set_button($buttons);
-    }
-
-    // If viewing a section, make the title more specific
-    if ($section and $section > 0 and course_format_uses_sections($course->format)) {
-        $sectionname = get_string('sectionname', "format_$course->format");
-        $sectiontitle = get_section_name($course, $section);
-        $PAGE->set_title(get_string('coursesectiontitle', 'moodle', array('course' => $course->fullname, 'sectiontitle' => $sectiontitle, 'sectionname' => $sectionname)));
-    } else {
-        $PAGE->set_title(get_string('coursetitle', 'moodle', array('course' => $course->fullname)));
-    }
-
-    // Add bulk editing control.
-    $bulkbutton = $renderer->bulk_editing_button($format);
-    if (!empty($bulkbutton)) {
-        $PAGE->add_header_action($bulkbutton);
-    }
-
-    $PAGE->set_heading($course->fullname);
-    echo $OUTPUT->header();
-
-    if ($USER->editing == 1) {
-
-        // MDL-65321 The backup libraries are quite heavy, only require the bare minimum.
-        require_once($CFG->dirroot . '/backup/util/helper/async_helper.class.php');
-
-        if (async_helper::is_async_pending($id, 'course', 'backup')) {
-            echo $OUTPUT->notification(get_string('pendingasyncedit', 'backup'), 'warning');
-        }
-    }
-
-    // Course wrapper start.
-    echo html_writer::start_tag('div', array('class'=>'course-content'));
-
-    // make sure that section 0 exists (this function will create one if it is missing)
-    course_create_sections_if_missing($course, 0);
-
-    // get information about course modules and existing module types
-    // format.php in course formats may rely on presence of these variables
+    // Get section details and check it exists.
     $modinfo = get_fast_modinfo($course);
-    $modnames = get_module_types_names();
-    $modnamesplural = get_module_types_names(true);
-    $modnamesused = $modinfo->get_used_module_names();
-    $mods = $modinfo->get_cms();
-    $sections = $modinfo->get_section_info_all();
+    $coursesections = $modinfo->get_section_info($section, MUST_EXIST);
 
-    // CAUTION, hacky fundamental variable defintion to follow!
-    // Note that because of the way course fromats are constructed though
-    // inclusion we pass parameters around this way..
-    $displaysection = $section;
+    // Check user is allowed to see it.
+    if (!$coursesections->uservisible) {
+        // Check if coursesection has conditions affecting availability and if
+        // so, output availability info.
+        if ($coursesections->visible && $coursesections->availableinfo) {
+            $sectionname = get_section_name($course, $coursesections);
+            $message = get_string('notavailablecourse', '', $sectionname);
+            redirect(course_get_url($course), $message, null, \core\output\notification::NOTIFY_ERROR);
+        } else {
+            // Note: We actually already know they don't have this capability
+            // or uservisible would have been true; this is just to get the
+            // correct error message shown.
+            require_capability('moodle/course:viewhiddensections', $context);
+        }
+    }
+}
 
-    // Include course AJAX
-    include_course_ajax($course, $modnamesused);
+// Fix course format if it is no longer installed.
+$format = course_get_format($course);
+$course->format = $format->get_format();
 
-    // Include the actual course format.
-    require($CFG->dirroot .'/course/format/'. $course->format .'/format.php');
-    // Content wrapper end.
+$PAGE->set_pagetype('course-view-' . $course->format);
+$PAGE->set_other_editing_capability('moodle/course:update');
+$PAGE->set_other_editing_capability('moodle/course:manageactivities');
+$PAGE->set_other_editing_capability('moodle/course:activityvisibility');
+if (course_format_uses_sections($course->format)) {
+    $PAGE->set_other_editing_capability('moodle/course:sectionvisibility');
+    $PAGE->set_other_editing_capability('moodle/course:movesections');
+}
 
-    echo html_writer::end_tag('div');
+// Preload course format renderer before output starts.
+// This is a little hacky but necessary since
+// format.php is not included until after output starts.
+$renderer = $format->get_renderer($PAGE);
 
-    // Trigger course viewed event.
-    // We don't trust $context here. Course format inclusion above executes in the global space. We can't assume
-    // anything after that point.
-    course_view(context_course::instance($course->id), $section);
+if ($resetuserallowedediting) {
+    // Ugly hack.
+    unset($PAGE->_user_allowed_editing);
+}
 
-    // If available, include the JS to prepare the download course content modal.
-    if ($candownloadcourse) {
-        $PAGE->requires->js_call_amd('core_course/downloadcontent', 'init');
+if (!isset($USER->editing)) {
+    $USER->editing = 0;
+}
+if ($PAGE->user_allowed_editing()) {
+    if (($edit == 1) && confirm_sesskey()) {
+        $USER->editing = 1;
+        // Redirect to site root if Editing is toggled on frontpage.
+        if ($course->id == SITEID) {
+            redirect($CFG->wwwroot .'/?redirect=0');
+        } else if (!empty($return)) {
+            redirect($CFG->wwwroot . $return);
+        } else {
+            $url = new moodle_url($PAGE->url, ['notifyeditingon' => 1]);
+            redirect($url);
+        }
+    } else if (($edit == 0) && confirm_sesskey()) {
+        $USER->editing = 0;
+        if (!empty($USER->activitycopy) && $USER->activitycopycourse == $course->id) {
+            $USER->activitycopy = false;
+            $USER->activitycopycourse = null;
+        }
+        // Redirect to site root if Editing is toggled on frontpage.
+        if ($course->id == SITEID) {
+            redirect($CFG->wwwroot .'/?redirect=0');
+        } else if (!empty($return)) {
+            redirect($CFG->wwwroot . $return);
+        } else {
+            redirect($PAGE->url);
+        }
     }
 
-    // Load the view JS module if completion tracking is enabled for this course.
-    $completion = new completion_info($course);
-    if ($completion->is_enabled()) {
-        $PAGE->requires->js_call_amd('core_course/view', 'init');
+    if (has_capability('moodle/course:sectionvisibility', $context)) {
+        if ($hide && confirm_sesskey()) {
+            set_section_visible($course->id, $hide, '0');
+            redirect($PAGE->url);
+        }
+
+        if ($show && confirm_sesskey()) {
+            set_section_visible($course->id, $show, '1');
+            redirect($PAGE->url);
+        }
     }
 
-    echo $OUTPUT->footer();
+    if (
+        !empty($section) && !empty($coursesections) && !empty($duplicatesection)
+        && has_capability('moodle/course:update', $context) && confirm_sesskey()
+    ) {
+        $newsection = $format->duplicate_section($coursesections);
+        redirect(course_get_url($course, $newsection->section));
+    }
+
+    if (!empty($section) && !empty($move) &&
+            has_capability('moodle/course:movesections', $context) && confirm_sesskey()) {
+        $destsection = $section + $move;
+        if (move_section_to($course, $section, $destsection)) {
+            if ($course->id == SITEID) {
+                redirect($CFG->wwwroot . '/?redirect=0');
+            } else {
+                if ($format->get_course_display() == COURSE_DISPLAY_MULTIPAGE) {
+                    redirect(course_get_url($course));
+                } else {
+                    redirect(course_get_url($course, $destsection));
+                }
+            }
+        } else {
+            echo $OUTPUT->notification('An error occurred while moving a section');
+        }
+    }
+} else {
+    $USER->editing = 0;
+}
+
+$SESSION->fromdiscussion = $PAGE->url->out(false);
+
+
+if ($course->id == SITEID) {
+    // This course is not a real course.
+    redirect($CFG->wwwroot .'/?redirect=0');
+}
+
+// Determine whether the user has permission to download course content.
+$candownloadcourse = \core\content::can_export_context($context, $USER);
+
+// We are currently keeping the button here from 1.x to help new teachers figure out
+// what to do, even though the link also appears in the course admin block.  It also
+// means you can back out of a situation where you removed the admin block.
+if ($PAGE->user_allowed_editing()) {
+    $buttons = $OUTPUT->edit_button($PAGE->url);
+    $PAGE->set_button($buttons);
+}
+
+// If viewing a section, make the title more specific.
+if ($section && $section > 0 && course_format_uses_sections($course->format)) {
+    $sectionname = get_string('sectionname', "format_$course->format");
+    $sectiontitle = get_section_name($course, $section);
+    $PAGE->set_title(
+        get_string(
+            'coursesectiontitle',
+            'moodle',
+            ['course' => $course->fullname, 'sectiontitle' => $sectiontitle, 'sectionname' => $sectionname]
+        )
+    );
+} else {
+    $PAGE->set_title(get_string('coursetitle', 'moodle', ['course' => $course->fullname]));
+}
+
+// Add bulk editing control.
+$bulkbutton = $renderer->bulk_editing_button($format);
+if (!empty($bulkbutton)) {
+    $PAGE->add_header_action($bulkbutton);
+}
+
+$PAGE->set_heading($course->fullname);
+echo $OUTPUT->header();
+
+if ($USER->editing == 1) {
+
+    // MDL-65321 The backup libraries are quite heavy, only require the bare minimum.
+    require_once($CFG->dirroot . '/backup/util/helper/async_helper.class.php');
+
+    if (async_helper::is_async_pending($id, 'course', 'backup')) {
+        echo $OUTPUT->notification(get_string('pendingasyncedit', 'backup'), 'warning');
+    }
+}
+
+// Course wrapper start.
+echo html_writer::start_tag('div', ['class' => 'course-content']);
+
+// Make sure that section 0 exists (this function will create one if it is missing).
+course_create_sections_if_missing($course, 0);
+
+// Get information about course modules and existing module types.
+// format.php in course formats may rely on presence of these variables.
+$modinfo = get_fast_modinfo($course);
+$modnames = get_module_types_names();
+$modnamesplural = get_module_types_names(true);
+$modnamesused = $modinfo->get_used_module_names();
+$mods = $modinfo->get_cms();
+$sections = $modinfo->get_section_info_all();
+
+// CAUTION, hacky fundamental variable defintion to follow!
+// Note that because of the way course fromats are constructed though
+// inclusion we pass parameters around this way.
+$displaysection = $section;
+
+// Include course AJAX.
+include_course_ajax($course, $modnamesused);
+
+// Include the actual course format.
+require($CFG->dirroot .'/course/format/'. $course->format .'/format.php');
+// Content wrapper end.
+
+echo html_writer::end_tag('div');
+
+// Trigger course viewed event.
+// We don't trust $context here. Course format inclusion above executes in the global space. We can't assume
+// anything after that point.
+course_view(context_course::instance($course->id), $section);
+
+// If available, include the JS to prepare the download course content modal.
+if ($candownloadcourse) {
+    $PAGE->requires->js_call_amd('core_course/downloadcontent', 'init');
+}
+
+// Load the view JS module if completion tracking is enabled for this course.
+$completion = new completion_info($course);
+if ($completion->is_enabled()) {
+    $PAGE->requires->js_call_amd('core_course/view', 'init');
+}
+
+echo $OUTPUT->footer();