/course/view.php

<?php

//  Display the course home page.

    require_once('../config.php');
    require_once('lib.php');
    require_once($CFG->dirroot.'/mod/forum/lib.php');
    require_once($CFG->libdir.'/completionlib.php');

    $id          = optional_param('id', 0, PARAM_INT);
    $name        = optional_param('name', '', PARAM_RAW);
    $edit        = optional_param('edit', -1, PARAM_BOOL);
    $hide        = optional_param('hide', 0, PARAM_INT);
    $show        = optional_param('show', 0, PARAM_INT);
    $idnumber    = optional_param('idnumber', '', PARAM_RAW);
    $section     = optional_param('section', 0, PARAM_INT);
    $move        = optional_param('move', 0, PARAM_INT);
    $marker      = optional_param('marker',-1 , PARAM_INT);
    $switchrole  = optional_param('switchrole',-1, PARAM_INT);

    if (empty($id) && empty($name) && empty($idnumber)) {
        print_error('unspecifycourseid', 'error');
    }

    if (!empty($name)) {
        if (! ($course = $DB->get_record('course', array('shortname'=>$name)))) {
            print_error('invalidcoursenameshort', 'error');
        }
    } else if (!empty($idnumber)) {
        if (! ($course = $DB->get_record('course', array('idnumber'=>$idnumber)))) {
            print_error('invalidcourseid', 'error');
        }
    } else {
        if (! ($course = $DB->get_record('course', array('id'=>$id)))) {
            print_error('invalidcourseid', 'error');
        }
    }

    $PAGE->set_url('/course/view.php', array('id' => $course->id)); // Defined here to avoid notices on errors etc

    preload_course_contexts($course->id);
    if (!$context = get_context_instance(CONTEXT_COURSE, $course->id)) {
        print_error('nocontext');
    }

    // 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...
    $reset_user_allowed_editing = false;
    if ($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->id);
        }
        // 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);
            }
        }
    }


    require_once($CFG->dirroot.'/calendar/lib.php');    /// This is after login because it needs $USER

    add_to_log($course->id, 'course', 'view', "view.php?id=$course->id", "$course->id");

    $course->format = clean_param($course->format, PARAM_ALPHA);
    if (!file_exists($CFG->dirroot.'/course/format/'.$course->format.'/format.php')) {
        $course->format = 'weeks';  // Default format is weeks
    }

    $PAGE->set_pagelayout('course');
    $PAGE->set_pagetype('course-view-' . $course->format);
    $PAGE->set_other_editing_capability('moodle/course:manageactivities');

    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()) {
            $USER->editing = 1;
            redirect($PAGE->url);
        } else if (($edit == 0) and confirm_sesskey()) {
            $USER->editing = 0;
            if(!empty($USER->activitycopy) && $USER->activitycopycourse == $course->id) {
                $USER->activitycopy       = false;
                $USER->activitycopycourse = NULL;
            }
            redirect($PAGE->url);
        }

        if ($hide && confirm_sesskey()) {
            set_section_visible($course->id, $hide, '0');
        }

        if ($show && confirm_sesskey()) {
            set_section_visible($course->id, $show, '1');
        }

        if (!empty($section)) {
            if (!empty($move) and confirm_sesskey()) {
                if (!move_section($course, $section, $move)) {
                    echo $OUTPUT->notification('An error occurred while moving a section');
                }
                // Clear the navigation cache at this point so that the affects
                // are seen immediately on the navigation.
                $PAGE->navigation->clear_cache();
            }
        }
    } else {
        $USER->editing = 0;
    }

    $SESSION->fromdiscussion = $CFG->wwwroot .'/course/view.php?id='. $course->id;


    if ($course->id == SITEID) {
        // This course is not a real course.
        redirect($CFG->wwwroot .'/');
    }

    // AJAX-capable course format?
    $useajax = false;
    $formatajax = course_format_ajax_support($course->format);

    if (!empty($CFG->enablecourseajax)
            and $formatajax->capable
            and !empty($USER->editing)
            and ajaxenabled($formatajax->testedbrowsers)
            and $PAGE->theme->enablecourseajax
            and has_capability('moodle/course:manageactivities', $context)) {
        $PAGE->requires->yui2_lib('dragdrop');
        $PAGE->requires->yui2_lib('connection');
        $PAGE->requires->yui2_lib('selector');
        $PAGE->requires->js('/lib/ajax/block_classes.js', true);
        $PAGE->requires->js('/lib/ajax/section_classes.js', true);

        // Okay, global variable alert. VERY UGLY. We need to create
        // this object here before the <blockname>_print_block()
        // function is called, since that function needs to set some
        // stuff in the javascriptportal object.
        $COURSE->javascriptportal = new jsportal();
        $useajax = true;
    }

    $CFG->blocksdrag = $useajax;   // this will add a new class to the header so we can style differently

    $completion = new completion_info($course);
    if ($completion->is_enabled() && ajaxenabled()) {
        $PAGE->requires->string_for_js('completion-title-manual-y', 'completion');
        $PAGE->requires->string_for_js('completion-title-manual-n', 'completion');
        $PAGE->requires->string_for_js('completion-alt-manual-y', 'completion');
        $PAGE->requires->string_for_js('completion-alt-manual-n', 'completion');

        $PAGE->requires->js_init_call('M.core_completion.init');
    }

    // 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(new moodle_url('/course/view.php', array('id' => $course->id)));
        $PAGE->set_button($buttons);
    }

    $PAGE->set_title(get_string('course') . ': ' . $course->fullname);
    $PAGE->set_heading($course->fullname);
    echo $OUTPUT->header();

    if ($completion->is_enabled() && ajaxenabled()) {
        // This value tracks whether there has been a dynamic change to the page.
        // It is used so that if a user does this - (a) set some tickmarks, (b)
        // go to another page, (c) clicks Back button - the page will
        // automatically reload. Otherwise it would start with the wrong tick
        // values.
        echo html_writer::start_tag('form', array('action'=>'.', 'method'=>'get'));
        echo html_writer::start_tag('div');
        echo html_writer::empty_tag('input', array('type'=>'hidden', 'id'=>'completion_dynamic_change', 'name'=>'completion_dynamic_change', 'value'=>'0'));
        echo html_writer::end_tag('div');
        echo html_writer::end_tag('form');
    }

    // Course wrapper start.
    echo html_writer::start_tag('div', array('class'=>'course-content'));

    $modinfo =& get_fast_modinfo($COURSE);
    get_all_mods($course->id, $mods, $modnames, $modnamesplural, $modnamesused);
    foreach($mods as $modid=>$unused) {
        if (!isset($modinfo->cms[$modid])) {
            rebuild_course_cache($course->id);
            $modinfo =& get_fast_modinfo($COURSE);
            debugging('Rebuilding course cache', DEBUG_DEVELOPER);
            break;
        }
    }

    if (! $sections = get_all_sections($course->id)) {   // No sections found
        // Double-check to be extra sure
        if (! $section = $DB->get_record('course_sections', array('course'=>$course->id, 'section'=>0))) {
            $section->course = $course->id;   // Create a default section.
            $section->section = 0;
            $section->visible = 1;
            $section->summaryformat = FORMAT_HTML;
            $section->id = $DB->insert_record('course_sections', $section);
        }
        if (! $sections = get_all_sections($course->id) ) {      // Try again
            print_error('cannotcreateorfindstructs', 'error');
        }
    }

    // Include the actual course format.
    require($CFG->dirroot .'/course/format/'. $course->format .'/format.php');
    // Content wrapper end.

    echo html_writer::end_tag('div');

    // Use AJAX?
    if ($useajax && has_capability('moodle/course:manageactivities', $context)) {
        // At the bottom because we want to process sections and activities
        // after the relevant html has been generated. We're forced to do this
        // because of the way in which lib/ajax/ajaxcourse.js is written.
        echo html_writer::script(false, new moodle_url('/lib/ajax/ajaxcourse.js'));
        $COURSE->javascriptportal->print_javascript($course->id);
    }


    echo $OUTPUT->footer();