if ($forum->type == 'qanda' && !has_capability('mod/forum:viewqandawithoutposting', $modcontext) && !empty($discussion->id) && !forum_user_has_posted($forum->id, $discussion->id, $USER->id)) {
    echo $OUTPUT->notification(get_string('qandanotify', 'forum'));
}
forum_check_throttling($forum, $cm);
if (!empty($parent)) {
    if (!($discussion = $DB->get_record('forum_discussions', array('id' => $parent->discussion)))) {
        print_error('notpartofdiscussion', 'forum');
    }
    // #marginalia begin
    $moodlemia = moodle_marginalia::get_instance();
    $miaprofile = $moodlemia->get_profile($PAGE->url->out(false));
    if ($miaprofile) {
        $miaprofile->emit_body();
        $miaprofile->emit_margin_controls();
    }
    // #marginalia end
    forum_print_post($parent, $discussion, $forum, $cm, $course, false, false, false);
    if (empty($post->edit)) {
        if ($forum->type != 'qanda' || forum_user_can_see_discussion($forum, $discussion, $modcontext)) {
            $forumtracked = forum_tp_is_tracked($forum);
            $posts = forum_get_all_discussion_posts($discussion->id, "created ASC", $forumtracked);
            forum_print_posts_threaded($course, $cm, $forum, $discussion, $parent, 0, false, $forumtracked, $posts);
        }
    }
} else {
    if (!empty($forum->intro)) {
        echo $OUTPUT->box(format_module_intro('forum', $forum, $cm->id), 'generalbox', 'intro');
    }
}
$mform_post->display();
echo $OUTPUT->footer();

    print_error('invalidcoursemodule');
}
if (!($cm = get_coursemodule_from_instance("forum", $forum->id, $course->id))) {
    print_error('invalidcoursemodule');
}
require_login($course, false, $cm);
$returnpageurl = new moodle_url('/mod/forum/' . $returnpage, array('id' => $course->id, 'f' => $forum->id));
$returnto = forum_go_back_to($returnpageurl);
if (!forum_tp_can_track_forums($forum)) {
    redirect($returnto);
}
$info = new stdClass();
$info->name = fullname($USER);
$info->forum = format_string($forum->name);
$eventparams = array('context' => context_module::instance($cm->id), 'relateduserid' => $USER->id, 'other' => array('forumid' => $forum->id));
if (forum_tp_is_tracked($forum)) {
    if (forum_tp_stop_tracking($forum->id)) {
        $event = \mod_forum\event\readtracking_disabled::create($eventparams);
        $event->trigger();
        redirect($returnto, get_string("nownottracking", "forum", $info), 1);
    } else {
        print_error('cannottrack', '', get_local_referer(false));
    }
} else {
    // subscribe
    if (forum_tp_start_tracking($forum->id)) {
        $event = \mod_forum\event\readtracking_enabled::create($eventparams);
        $event->trigger();
        redirect($returnto, get_string("nowtracking", "forum", $info), 1);
    } else {
        print_error('cannottrack', '', get_local_referer(false));

//.........这里部分代码省略.........
                // 0
                $allowchoice->action = null;
                $allowchoice->add_class('activesetting');
                $allowchoice->icon = new pix_icon('t/selected', '', 'mod_forum');
                break;
            case FORUM_FORCESUBSCRIBE:
                // 1
                $forceforever->action = null;
                $forceforever->add_class('activesetting');
                $forceforever->icon = new pix_icon('t/selected', '', 'mod_forum');
                break;
            case FORUM_INITIALSUBSCRIBE:
                // 2
                $forceinitially->action = null;
                $forceinitially->add_class('activesetting');
                $forceinitially->icon = new pix_icon('t/selected', '', 'mod_forum');
                break;
            case FORUM_DISALLOWSUBSCRIBE:
                // 3
                $disallowchoice->action = null;
                $disallowchoice->add_class('activesetting');
                $disallowchoice->icon = new pix_icon('t/selected', '', 'mod_forum');
                break;
        }
    } else {
        if ($activeenrolled) {
            switch ($subscriptionmode) {
                case FORUM_CHOOSESUBSCRIBE:
                    // 0
                    $notenode = $forumnode->add(get_string('subscriptionoptional', 'forum'));
                    break;
                case FORUM_FORCESUBSCRIBE:
                    // 1
                    $notenode = $forumnode->add(get_string('subscriptionforced', 'forum'));
                    break;
                case FORUM_INITIALSUBSCRIBE:
                    // 2
                    $notenode = $forumnode->add(get_string('subscriptionauto', 'forum'));
                    break;
                case FORUM_DISALLOWSUBSCRIBE:
                    // 3
                    $notenode = $forumnode->add(get_string('subscriptiondisabled', 'forum'));
                    break;
            }
        }
    }
    if ($cansubscribe) {
        if (\mod_forum\subscriptions::is_subscribed($USER->id, $forumobject, null, $PAGE->cm)) {
            $linktext = get_string('unsubscribe', 'forum');
        } else {
            $linktext = get_string('subscribe', 'forum');
        }
        $url = new moodle_url('/mod/forum/subscribe.php', array('id' => $forumobject->id, 'sesskey' => sesskey()));
        $forumnode->add($linktext, $url, navigation_node::TYPE_SETTING);
        if (isset($discussionid)) {
            if (\mod_forum\subscriptions::is_subscribed($USER->id, $forumobject, $discussionid, $PAGE->cm)) {
                $linktext = get_string('unsubscribediscussion', 'forum');
            } else {
                $linktext = get_string('subscribediscussion', 'forum');
            }
            $url = new moodle_url('/mod/forum/subscribe.php', array('id' => $forumobject->id, 'sesskey' => sesskey(), 'd' => $discussionid, 'returnurl' => $PAGE->url->out()));
            $forumnode->add($linktext, $url, navigation_node::TYPE_SETTING);
        }
    }
    if (has_capability('mod/forum:viewsubscribers', $PAGE->cm->context)) {
        $url = new moodle_url('/mod/forum/subscribers.php', array('id' => $forumobject->id));
        $forumnode->add(get_string('showsubscribers', 'forum'), $url, navigation_node::TYPE_SETTING);
    }
    if ($enrolled && forum_tp_can_track_forums($forumobject)) {
        // keep tracking info for users with suspended enrolments
        if ($forumobject->trackingtype == FORUM_TRACKING_OPTIONAL || !$CFG->forum_allowforcedreadtracking && $forumobject->trackingtype == FORUM_TRACKING_FORCED) {
            if (forum_tp_is_tracked($forumobject)) {
                $linktext = get_string('notrackforum', 'forum');
            } else {
                $linktext = get_string('trackforum', 'forum');
            }
            $url = new moodle_url('/mod/forum/settracking.php', array('id' => $forumobject->id, 'sesskey' => sesskey()));
            $forumnode->add($linktext, $url, navigation_node::TYPE_SETTING);
        }
    }
    if (!isloggedin() && $PAGE->course->id == SITEID) {
        $userid = guest_user()->id;
    } else {
        $userid = $USER->id;
    }
    $hascourseaccess = $PAGE->course->id == SITEID || can_access_course($PAGE->course, $userid);
    $enablerssfeeds = !empty($CFG->enablerssfeeds) && !empty($CFG->forum_enablerssfeeds);
    if ($enablerssfeeds && $forumobject->rsstype && $forumobject->rssarticles && $hascourseaccess) {
        if (!function_exists('rss_get_url')) {
            require_once "{$CFG->libdir}/rsslib.php";
        }
        if ($forumobject->rsstype == 1) {
            $string = get_string('rsssubscriberssdiscussions', 'forum');
        } else {
            $string = get_string('rsssubscriberssposts', 'forum');
        }
        $url = new moodle_url(rss_get_url($PAGE->cm->context->id, $userid, "mod_forum", $forumobject->id));
        $forumnode->add($string, $url, settings_navigation::TYPE_SETTING, null, null, new pix_icon('i/rss', ''));
    }
}

 /**
  * Returns a list of forum posts for a discussion
  *
  * @param int $discussionid the post ids
  * @param string $sortby sort by this element (id, created or modified)
  * @param string $sortdirection sort direction: ASC or DESC
  *
  * @return array the forum post details
  * @since Moodle 2.7
  */
 public static function get_forum_discussion_posts($discussionid, $sortby = "created", $sortdirection = "DESC")
 {
     global $CFG, $DB, $USER;
     $warnings = array();
     // Validate the parameter.
     $params = self::validate_parameters(self::get_forum_discussion_posts_parameters(), array('discussionid' => $discussionid, 'sortby' => $sortby, 'sortdirection' => $sortdirection));
     // Compact/extract functions are not recommended.
     $discussionid = $params['discussionid'];
     $sortby = $params['sortby'];
     $sortdirection = $params['sortdirection'];
     $sortallowedvalues = array('id', 'created', 'modified');
     if (!in_array($sortby, $sortallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortby parameter (value: ' . $sortby . '),' . 'allowed values are: ' . implode(',', $sortallowedvalues));
     }
     $sortdirection = strtoupper($sortdirection);
     $directionallowedvalues = array('ASC', 'DESC');
     if (!in_array($sortdirection, $directionallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortdirection parameter (value: ' . $sortdirection . '),' . 'allowed values are: ' . implode(',', $directionallowedvalues));
     }
     $discussion = $DB->get_record('forum_discussions', array('id' => $discussionid), '*', MUST_EXIST);
     $forum = $DB->get_record('forum', array('id' => $discussion->forum), '*', MUST_EXIST);
     $course = $DB->get_record('course', array('id' => $forum->course), '*', MUST_EXIST);
     $cm = get_coursemodule_from_instance('forum', $forum->id, $course->id, false, MUST_EXIST);
     // Validate the module context. It checks everything that affects the module visibility (including groupings, etc..).
     $modcontext = context_module::instance($cm->id);
     self::validate_context($modcontext);
     // This require must be here, see mod/forum/discuss.php.
     require_once $CFG->dirroot . "/mod/forum/lib.php";
     // Check they have the view forum capability.
     require_capability('mod/forum:viewdiscussion', $modcontext, null, true, 'noviewdiscussionspermission', 'forum');
     if (!($post = forum_get_post_full($discussion->firstpost))) {
         throw new moodle_exception('notexists', 'forum');
     }
     // This function check groups, qanda, timed discussions, etc.
     if (!forum_user_can_see_post($forum, $discussion, $post, null, $cm)) {
         throw new moodle_exception('noviewdiscussionspermission', 'forum');
     }
     $canviewfullname = has_capability('moodle/site:viewfullnames', $modcontext);
     // We will add this field in the response.
     $canreply = forum_user_can_post($forum, $discussion, $USER, $cm, $course, $modcontext);
     $forumtracked = forum_tp_is_tracked($forum);
     $sort = 'p.' . $sortby . ' ' . $sortdirection;
     $posts = forum_get_all_discussion_posts($discussion->id, $sort, $forumtracked);
     foreach ($posts as $pid => $post) {
         if (!forum_user_can_see_post($forum, $discussion, $post, null, $cm)) {
             $warning = array();
             $warning['item'] = 'post';
             $warning['itemid'] = $post->id;
             $warning['warningcode'] = '1';
             $warning['message'] = 'You can\'t see this post';
             $warnings[] = $warning;
             continue;
         }
         // Function forum_get_all_discussion_posts adds postread field.
         // Note that the value returned can be a boolean or an integer. The WS expects a boolean.
         if (empty($post->postread)) {
             $posts[$pid]->postread = false;
         } else {
             $posts[$pid]->postread = true;
         }
         $posts[$pid]->canreply = $canreply;
         if (!empty($posts[$pid]->children)) {
             $posts[$pid]->children = array_keys($posts[$pid]->children);
         } else {
             $posts[$pid]->children = array();
         }
         $user = new stdclass();
         $user = username_load_fields_from_object($user, $post);
         $posts[$pid]->userfullname = fullname($user, $canviewfullname);
         $posts[$pid] = (array) $post;
     }
     $result = array();
     $result['posts'] = $posts;
     $result['warnings'] = $warnings;
     return $result;
 }

}
// checkup
if (!empty($parent) && !forum_user_can_see_post($forum, $discussion, $post)) {
    error("You cannot reply to this post");
}
if (empty($parent) && empty($edit) && !forum_user_can_post_discussion($forum)) {
    error("You cannot start a new discussion in this forum");
}
if ($forum->type == 'qanda' && !has_capability('mod/forum:viewqandawithoutposting', $modcontext) && !empty($discussion->id) && !forum_user_has_posted($forum->id, $discussion->id, $USER->id)) {
    notify(get_string('qandanotify', 'forum'));
}
forum_check_throttling($forum);
if (!empty($parent)) {
    forum_print_post($parent, $course->id, $ownpost = false, $reply = false, $link = false);
    if (empty($post->edit)) {
        if (forum_tp_can_track_forums($forum) && forum_tp_is_tracked($forum)) {
            $user_read_array = forum_tp_get_discussion_read_records($USER->id, $discussion->id);
        } else {
            $user_read_array = array();
        }
        if ($forum->type != 'qanda' || forum_user_can_see_discussion($forum, $discussion, $modcontext)) {
            forum_print_posts_threaded($parent->id, $course->id, 0, false, false, $user_read_array, $discussion->forum, $modcontext);
        }
    }
    $heading = get_string("yourreply", "forum");
} else {
    $forum->intro = trim($forum->intro);
    if (!empty($forum->intro)) {
        print_box(format_text($forum->intro), 'generalbox', 'intro');
    }
    if ($forum->type == 'qanda') {

//.........这里部分代码省略.........
            echo '(' . get_string('nonews', 'forum') . ')';
        } else {
            if ($forum->type == 'qanda') {
                echo '(' . get_string('noquestions', 'forum') . ')';
            } else {
                echo '(' . get_string('nodiscussions', 'forum') . ')';
            }
        }
        echo "</div>\n";
        return;
    }
    // If we want paging
    if ($page != -1) {
        ///Get the number of discussions found
        $numdiscussions = forum_get_discussions_count($cm);
        ///Show the paging bar
        echo $OUTPUT->paging_bar($numdiscussions, $page, $perpage, "view.php?f={$forum->id}");
        if ($numdiscussions > 1000) {
            // saves some memory on sites with very large forums
            $replies = forum_count_discussion_replies($forum->id, $sort, $maxdiscussions, $page, $perpage);
        } else {
            $replies = forum_count_discussion_replies($forum->id);
        }
    } else {
        $replies = forum_count_discussion_replies($forum->id);
        if ($maxdiscussions > 0 and $maxdiscussions <= count($discussions)) {
            $olddiscussionlink = true;
        }
    }
    $canviewparticipants = has_capability('moodle/course:viewparticipants', $context);
    $strdatestring = get_string('strftimerecentfull');
    // Check if the forum is tracked.
    if ($cantrack = forum_tp_can_track_forums($forum)) {
        $forumtracked = forum_tp_is_tracked($forum);
    } else {
        $forumtracked = false;
    }
    if ($forumtracked) {
        $unreads = forum_get_discussions_unread($cm);
    } else {
        $unreads = array();
    }
    if ($displayformat == 'header') {
        echo '<table cellspacing="0" class="forumheaderlist">';
        echo '<thead>';
        echo '<tr>';
        echo '<th class="header topic" scope="col">' . get_string('discussion', 'forum') . '</th>';
        echo '<th class="header author" colspan="2" scope="col">' . get_string('startedby', 'forum') . '</th>';
        if ($groupmode > 0) {
            echo '<th class="header group" scope="col">' . get_string('group') . '</th>';
        }
        if (has_capability('mod/forum:viewdiscussion', $context)) {
            echo '<th class="header replies" scope="col">' . get_string('replies', 'forum') . '</th>';
            // If the forum can be tracked, display the unread column.
            if ($cantrack) {
                echo '<th class="header replies" scope="col">' . get_string('unread', 'forum');
                if ($forumtracked) {
                    echo '<a title="' . get_string('markallread', 'forum') . '" href="' . $CFG->wwwroot . '/mod/forum/markposts.php?f=' . $forum->id . '&amp;mark=read&amp;returnpage=view.php">' . '<img src="' . $OUTPUT->pix_url('t/markasread') . '" class="iconsmall" alt="' . get_string('markallread', 'forum') . '" /></a>';
                }
                echo '</th>';
            }
        }
        echo '<th class="header lastpost" scope="col">' . get_string('lastpost', 'forum') . '</th>';
        if (!is_guest($context, $USER) && isloggedin() && has_capability('mod/forum:viewdiscussion', $context)) {
            if (\mod_forum\subscriptions::is_subscribable($forum)) {
                echo '<th class="header discussionsubscription" scope="col">';

 /**
  * Test the logic in the test_forum_tp_is_tracked() function.
  */
 public function test_forum_tp_is_tracked()
 {
     global $CFG;
     $this->resetAfterTest();
     $useron = $this->getDataGenerator()->create_user(array('trackforums' => 1));
     $useroff = $this->getDataGenerator()->create_user(array('trackforums' => 0));
     $course = $this->getDataGenerator()->create_course();
     $options = array('course' => $course->id, 'trackingtype' => FORUM_TRACKING_OFF);
     // Off.
     $forumoff = $this->getDataGenerator()->create_module('forum', $options);
     $options = array('course' => $course->id, 'trackingtype' => FORUM_TRACKING_FORCED);
     // On.
     $forumforce = $this->getDataGenerator()->create_module('forum', $options);
     $options = array('course' => $course->id, 'trackingtype' => FORUM_TRACKING_OPTIONAL);
     // Optional.
     $forumoptional = $this->getDataGenerator()->create_module('forum', $options);
     // Allow force.
     $CFG->forum_allowforcedreadtracking = 1;
     // User on, forum off, should be off.
     $result = forum_tp_is_tracked($forumoff, $useron);
     $this->assertEquals(false, $result);
     // User on, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useron);
     $this->assertEquals(true, $result);
     // User on, forum optional, should be on.
     $result = forum_tp_is_tracked($forumoptional, $useron);
     $this->assertEquals(true, $result);
     // User off, forum off, should be off.
     $result = forum_tp_is_tracked($forumoff, $useroff);
     $this->assertEquals(false, $result);
     // User off, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useroff);
     $this->assertEquals(true, $result);
     // User off, forum optional, should be off.
     $result = forum_tp_is_tracked($forumoptional, $useroff);
     $this->assertEquals(false, $result);
     // Don't allow force.
     $CFG->forum_allowforcedreadtracking = 0;
     // User on, forum off, should be off.
     $result = forum_tp_is_tracked($forumoff, $useron);
     $this->assertEquals(false, $result);
     // User on, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useron);
     $this->assertEquals(true, $result);
     // User on, forum optional, should be on.
     $result = forum_tp_is_tracked($forumoptional, $useron);
     $this->assertEquals(true, $result);
     // User off, forum off, should be off.
     $result = forum_tp_is_tracked($forumoff, $useroff);
     $this->assertEquals(false, $result);
     // User off, forum force, should be off.
     $result = forum_tp_is_tracked($forumforce, $useroff);
     $this->assertEquals(false, $result);
     // User off, forum optional, should be off.
     $result = forum_tp_is_tracked($forumoptional, $useroff);
     $this->assertEquals(false, $result);
     // Stop tracking so we can test again.
     forum_tp_stop_tracking($forumforce->id, $useron->id);
     forum_tp_stop_tracking($forumoptional->id, $useron->id);
     forum_tp_stop_tracking($forumforce->id, $useroff->id);
     forum_tp_stop_tracking($forumoptional->id, $useroff->id);
     // Allow force.
     $CFG->forum_allowforcedreadtracking = 1;
     // User on, preference off, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useron);
     $this->assertEquals(true, $result);
     // User on, preference off, forum optional, should be on.
     $result = forum_tp_is_tracked($forumoptional, $useron);
     $this->assertEquals(false, $result);
     // User off, preference off, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useroff);
     $this->assertEquals(true, $result);
     // User off, preference off, forum optional, should be off.
     $result = forum_tp_is_tracked($forumoptional, $useroff);
     $this->assertEquals(false, $result);
     // Don't allow force.
     $CFG->forum_allowforcedreadtracking = 0;
     // User on, preference off, forum force, should be on.
     $result = forum_tp_is_tracked($forumforce, $useron);
     $this->assertEquals(false, $result);
     // User on, preference off, forum optional, should be on.
     $result = forum_tp_is_tracked($forumoptional, $useron);
     $this->assertEquals(false, $result);
     // User off, preference off, forum force, should be off.
     $result = forum_tp_is_tracked($forumforce, $useroff);
     $this->assertEquals(false, $result);
     // User off, preference off, forum optional, should be off.
     $result = forum_tp_is_tracked($forumoptional, $useroff);
     $this->assertEquals(false, $result);
 }

/**
 *
 */
function forum_print_discussion($course, $cm, $forum, $discussion, $post, $mode, $canreply = NULL, $canrate = false)
{
    global $USER, $CFG;
    if (!empty($USER->id)) {
        $ownpost = $USER->id == $post->userid;
    } else {
        $ownpost = false;
    }
    if ($canreply === NULL) {
        $modcontext = get_context_instance(CONTEXT_MODULE, $cm->id);
        $reply = forum_user_can_post($forum, $discussion, $USER, $cm, $course, $modcontext);
    } else {
        $reply = $canreply;
    }
    // $cm holds general cache for forum functions
    $cm->cache = new object();
    $cm->cache->groups = groups_get_all_groups($course->id, 0, $cm->groupingid);
    $cm->cache->usersgroups = array();
    $posters = array();
    // preload all posts - TODO: improve...
    if ($mode == FORUM_MODE_FLATNEWEST) {
        $sort = "p.created DESC";
    } else {
        $sort = "p.created ASC";
    }
    $forumtracked = forum_tp_is_tracked($forum);
    $posts = forum_get_all_discussion_posts($discussion->id, $sort, $forumtracked);
    $post = $posts[$post->id];
    foreach ($posts as $pid => $p) {
        $posters[$p->userid] = $p->userid;
    }
    // preload all groups of ppl that posted in this discussion
    if ($postersgroups = groups_get_all_groups($course->id, $posters, $cm->groupingid, 'gm.id, gm.groupid, gm.userid')) {
        foreach ($postersgroups as $pg) {
            if (!isset($cm->cache->usersgroups[$pg->userid])) {
                $cm->cache->usersgroups[$pg->userid] = array();
            }
            $cm->cache->usersgroups[$pg->userid][$pg->groupid] = $pg->groupid;
        }
        unset($postersgroups);
    }
    $ratings = NULL;
    $ratingsmenuused = false;
    $ratingsformused = false;
    if ($forum->assessed and isloggedin()) {
        if ($ratings->scale = make_grades_menu($forum->scale)) {
            $ratings->assesstimestart = $forum->assesstimestart;
            $ratings->assesstimefinish = $forum->assesstimefinish;
            $ratings->allow = $canrate;
            if ($ratings->allow) {
                echo '<form id="form" method="post" action="rate.php">';
                echo '<div class="ratingform">';
                echo '<input type="hidden" name="forumid" value="' . $forum->id . '" />';
                $ratingsformused = true;
            }
            // preload all ratings - one query only and minimal memory
            $cm->cache->ratings = array();
            $cm->cache->myratings = array();
            if ($postratings = forum_get_all_discussion_ratings($discussion)) {
                foreach ($postratings as $pr) {
                    if (!isset($cm->cache->ratings[$pr->postid])) {
                        $cm->cache->ratings[$pr->postid] = array();
                    }
                    $cm->cache->ratings[$pr->postid][$pr->id] = $pr->rating;
                    if ($pr->userid == $USER->id) {
                        $cm->cache->myratings[$pr->postid] = $pr->rating;
                    }
                }
                unset($postratings);
            }
        }
    }
    $post->forum = $forum->id;
    // Add the forum id to the post object, later used by forum_print_post
    $post->forumtype = $forum->type;
    $post->subject = format_string($post->subject);
    $postread = !empty($post->postread);
    if (forum_print_post($post, $discussion, $forum, $cm, $course, $ownpost, $reply, false, $ratings, '', '', $postread, true, $forumtracked)) {
        $ratingsmenuused = true;
    }
    switch ($mode) {
        case FORUM_MODE_FLATOLDEST:
        case FORUM_MODE_FLATNEWEST:
        default:
            if (forum_print_posts_flat($course, $cm, $forum, $discussion, $post, $mode, $ratings, $reply, $forumtracked, $posts)) {
                $ratingsmenuused = true;
            }
            break;
        case FORUM_MODE_THREADED:
            if (forum_print_posts_threaded($course, $cm, $forum, $discussion, $post, 0, $ratings, $reply, $forumtracked, $posts)) {
                $ratingsmenuused = true;
            }
            break;
        case FORUM_MODE_NESTED:
            if (forum_print_posts_nested($course, $cm, $forum, $discussion, $post, $ratings, $reply, $forumtracked, $posts)) {
                $ratingsmenuused = true;
            }
//.........这里部分代码省略.........

 /**
  * Returns a list of forum discussions optionally sorted and paginated.
  *
  * @param int $forumid the forum instance id
  * @param string $sortby sort by this element (id, timemodified, timestart or timeend)
  * @param string $sortdirection sort direction: ASC or DESC
  * @param int $page page number
  * @param int $perpage items per page
  *
  * @return array the forum discussion details including warnings
  * @since Moodle 2.8
  */
 public static function get_forum_discussions_paginated($forumid, $sortby = 'timemodified', $sortdirection = 'DESC', $page = -1, $perpage = 0)
 {
     global $CFG, $DB, $USER;
     require_once $CFG->dirroot . "/mod/forum/lib.php";
     $warnings = array();
     $discussions = array();
     $params = self::validate_parameters(self::get_forum_discussions_paginated_parameters(), array('forumid' => $forumid, 'sortby' => $sortby, 'sortdirection' => $sortdirection, 'page' => $page, 'perpage' => $perpage));
     // Compact/extract functions are not recommended.
     $forumid = $params['forumid'];
     $sortby = $params['sortby'];
     $sortdirection = $params['sortdirection'];
     $page = $params['page'];
     $perpage = $params['perpage'];
     $sortallowedvalues = array('id', 'timemodified', 'timestart', 'timeend');
     if (!in_array($sortby, $sortallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortby parameter (value: ' . $sortby . '),' . 'allowed values are: ' . implode(',', $sortallowedvalues));
     }
     $sortdirection = strtoupper($sortdirection);
     $directionallowedvalues = array('ASC', 'DESC');
     if (!in_array($sortdirection, $directionallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortdirection parameter (value: ' . $sortdirection . '),' . 'allowed values are: ' . implode(',', $directionallowedvalues));
     }
     $forum = $DB->get_record('forum', array('id' => $forumid), '*', MUST_EXIST);
     $course = $DB->get_record('course', array('id' => $forum->course), '*', MUST_EXIST);
     $cm = get_coursemodule_from_instance('forum', $forum->id, $course->id, false, MUST_EXIST);
     // Validate the module context. It checks everything that affects the module visibility (including groupings, etc..).
     $modcontext = context_module::instance($cm->id);
     self::validate_context($modcontext);
     // Check they have the view forum capability.
     require_capability('mod/forum:viewdiscussion', $modcontext, null, true, 'noviewdiscussionspermission', 'forum');
     $sort = 'd.' . $sortby . ' ' . $sortdirection;
     $alldiscussions = forum_get_discussions($cm, $sort, true, -1, -1, true, $page, $perpage);
     if ($alldiscussions) {
         $canviewfullname = has_capability('moodle/site:viewfullnames', $modcontext);
         // Get the unreads array, this takes a forum id and returns data for all discussions.
         $unreads = array();
         if ($cantrack = forum_tp_can_track_forums($forum)) {
             if ($forumtracked = forum_tp_is_tracked($forum)) {
                 $unreads = forum_get_discussions_unread($cm);
             }
         }
         // The forum function returns the replies for all the discussions in a given forum.
         $replies = forum_count_discussion_replies($forumid, $sort, -1, $page, $perpage);
         foreach ($alldiscussions as $discussion) {
             // This function checks for qanda forums.
             // Note that the forum_get_discussions returns as id the post id, not the discussion id so we need to do this.
             $discussionrec = clone $discussion;
             $discussionrec->id = $discussion->discussion;
             if (!forum_user_can_see_discussion($forum, $discussionrec, $modcontext)) {
                 $warning = array();
                 // Function forum_get_discussions returns forum_posts ids not forum_discussions ones.
                 $warning['item'] = 'post';
                 $warning['itemid'] = $discussion->id;
                 $warning['warningcode'] = '1';
                 $warning['message'] = 'You can\'t see this discussion';
                 $warnings[] = $warning;
                 continue;
             }
             $discussion->numunread = 0;
             if ($cantrack && $forumtracked) {
                 if (isset($unreads[$discussion->discussion])) {
                     $discussion->numunread = (int) $unreads[$discussion->discussion];
                 }
             }
             $discussion->numreplies = 0;
             if (!empty($replies[$discussion->discussion])) {
                 $discussion->numreplies = (int) $replies[$discussion->discussion]->replies;
             }
             // Load user objects from the results of the query.
             $user = new stdclass();
             $user->id = $discussion->userid;
             $user = username_load_fields_from_object($user, $discussion);
             $discussion->userfullname = fullname($user, $canviewfullname);
             // We can have post written by users that are deleted. In this case, those users don't have a valid context.
             $usercontext = context_user::instance($user->id, IGNORE_MISSING);
             if ($usercontext) {
                 $discussion->userpictureurl = moodle_url::make_webservice_pluginfile_url($usercontext->id, 'user', 'icon', null, '/', 'f1')->out(false);
             } else {
                 $discussion->userpictureurl = '';
             }
             $usermodified = new stdclass();
             $usermodified->id = $discussion->usermodified;
             $usermodified = username_load_fields_from_object($usermodified, $discussion, 'um');
             $discussion->usermodifiedfullname = fullname($usermodified, $canviewfullname);
             // We can have post written by users that are deleted. In this case, those users don't have a valid context.
             $usercontext = context_user::instance($usermodified->id, IGNORE_MISSING);
             if ($usercontext) {
                 $discussion->usermodifiedpictureurl = moodle_url::make_webservice_pluginfile_url($usercontext->id, 'user', 'icon', null, '/', 'f1')->out(false);
//.........这里部分代码省略.........

            } else {
                echo '<span class="helplink">' . $streveryonecannowchoose . '</span>';
            }
            if (forum_is_subscribed($USER->id, $forum->id)) {
                $subtexttitle = get_string('subscribestop', 'forum');
                $subtext = get_string('unsubscribe', 'forum');
            } else {
                $subtexttitle = get_string('subscribestart', 'forum');
                $subtext = get_string('subscribe', 'forum');
            }
            echo "<br />";
            echo "<span class=\"helplink\"><a title=\"{$subtexttitle}\" href=\"subscribe.php?id={$forum->id}\">{$subtext}</a></span>";
        }
    }
    if (forum_tp_can_track_forums($forum) && $forum->trackingtype == FORUM_TRACKING_OPTIONAL) {
        if (forum_tp_is_tracked($forum, $USER->id)) {
            $trtitle = get_string('notrackforum', 'forum');
            $trackedlink = '<a title="' . get_string('notrackforum', 'forum') . '" href="settracking.php?id=' . $forum->id . '&amp;returnpage=view.php">' . get_string('forumtracked', 'forum') . '</a>';
        } else {
            $trtitle = get_string('trackforum', 'forum');
            $trackedlink = '<a title="' . get_string('trackforum', 'forum') . '" href="settracking.php?id=' . $forum->id . '&amp;returnpage=view.php">' . get_string('forumtrackednot', 'forum') . '</a>';
        }
        echo '<br />';
        echo "<span class=\"helplink\">{$trackedlink}</span>";
    }
}
/// If rss are activated at site and forum level and this forum has rss defined, show link
if (isset($CFG->enablerssfeeds) && isset($CFG->forum_enablerssfeeds) && $CFG->enablerssfeeds && $CFG->forum_enablerssfeeds && $forum->rsstype and $forum->rssarticles) {
    if ($forum->rsstype == 1) {
        $tooltiptext = get_string('rsssubscriberssdiscussions', 'forum', format_string($forum->name));
    } else {

 /**
  * Returns a list of forum discussions optionally sorted and paginated.
  *
  * @param int $forumid the forum instance id
  * @param string $sortby sort by this element (id, timemodified, timestart or timeend)
  * @param string $sortdirection sort direction: ASC or DESC
  * @param int $page page number
  * @param int $perpage items per page
  *
  * @return array the forum discussion details including warnings
  * @since Moodle 2.8
  */
 public static function get_forum_discussions_paginated($forumid, $sortby = 'timemodified', $sortdirection = 'DESC', $page = -1, $perpage = 0)
 {
     global $CFG, $DB, $USER, $PAGE;
     require_once $CFG->dirroot . "/mod/forum/lib.php";
     $warnings = array();
     $discussions = array();
     $params = self::validate_parameters(self::get_forum_discussions_paginated_parameters(), array('forumid' => $forumid, 'sortby' => $sortby, 'sortdirection' => $sortdirection, 'page' => $page, 'perpage' => $perpage));
     // Compact/extract functions are not recommended.
     $forumid = $params['forumid'];
     $sortby = $params['sortby'];
     $sortdirection = $params['sortdirection'];
     $page = $params['page'];
     $perpage = $params['perpage'];
     $sortallowedvalues = array('id', 'timemodified', 'timestart', 'timeend');
     if (!in_array($sortby, $sortallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortby parameter (value: ' . $sortby . '),' . 'allowed values are: ' . implode(',', $sortallowedvalues));
     }
     $sortdirection = strtoupper($sortdirection);
     $directionallowedvalues = array('ASC', 'DESC');
     if (!in_array($sortdirection, $directionallowedvalues)) {
         throw new invalid_parameter_exception('Invalid value for sortdirection parameter (value: ' . $sortdirection . '),' . 'allowed values are: ' . implode(',', $directionallowedvalues));
     }
     $forum = $DB->get_record('forum', array('id' => $forumid), '*', MUST_EXIST);
     $course = $DB->get_record('course', array('id' => $forum->course), '*', MUST_EXIST);
     $cm = get_coursemodule_from_instance('forum', $forum->id, $course->id, false, MUST_EXIST);
     // Validate the module context. It checks everything that affects the module visibility (including groupings, etc..).
     $modcontext = context_module::instance($cm->id);
     self::validate_context($modcontext);
     // Check they have the view forum capability.
     require_capability('mod/forum:viewdiscussion', $modcontext, null, true, 'noviewdiscussionspermission', 'forum');
     $sort = 'd.pinned DESC, d.' . $sortby . ' ' . $sortdirection;
     $alldiscussions = forum_get_discussions($cm, $sort, true, -1, -1, true, $page, $perpage, FORUM_POSTS_ALL_USER_GROUPS);
     if ($alldiscussions) {
         $canviewfullname = has_capability('moodle/site:viewfullnames', $modcontext);
         // Get the unreads array, this takes a forum id and returns data for all discussions.
         $unreads = array();
         if ($cantrack = forum_tp_can_track_forums($forum)) {
             if ($forumtracked = forum_tp_is_tracked($forum)) {
                 $unreads = forum_get_discussions_unread($cm);
             }
         }
         // The forum function returns the replies for all the discussions in a given forum.
         $replies = forum_count_discussion_replies($forumid, $sort, -1, $page, $perpage);
         foreach ($alldiscussions as $discussion) {
             // This function checks for qanda forums.
             // Note that the forum_get_discussions returns as id the post id, not the discussion id so we need to do this.
             $discussionrec = clone $discussion;
             $discussionrec->id = $discussion->discussion;
             if (!forum_user_can_see_discussion($forum, $discussionrec, $modcontext)) {
                 $warning = array();
                 // Function forum_get_discussions returns forum_posts ids not forum_discussions ones.
                 $warning['item'] = 'post';
                 $warning['itemid'] = $discussion->id;
                 $warning['warningcode'] = '1';
                 $warning['message'] = 'You can\'t see this discussion';
                 $warnings[] = $warning;
                 continue;
             }
             $discussion->numunread = 0;
             if ($cantrack && $forumtracked) {
                 if (isset($unreads[$discussion->discussion])) {
                     $discussion->numunread = (int) $unreads[$discussion->discussion];
                 }
             }
             $discussion->numreplies = 0;
             if (!empty($replies[$discussion->discussion])) {
                 $discussion->numreplies = (int) $replies[$discussion->discussion]->replies;
             }
             $discussion->name = external_format_string($discussion->name, $modcontext->id);
             $discussion->subject = external_format_string($discussion->subject, $modcontext->id);
             // Rewrite embedded images URLs.
             list($discussion->message, $discussion->messageformat) = external_format_text($discussion->message, $discussion->messageformat, $modcontext->id, 'mod_forum', 'post', $discussion->id);
             // List attachments.
             if (!empty($discussion->attachment)) {
                 $discussion->attachments = external_util::get_area_files($modcontext->id, 'mod_forum', 'attachment', $discussion->id);
             }
             $messageinlinefiles = external_util::get_area_files($modcontext->id, 'mod_forum', 'post', $discussion->id);
             if (!empty($messageinlinefiles)) {
                 $discussion->messageinlinefiles = $messageinlinefiles;
             }
             $discussion->locked = forum_discussion_is_locked($forum, $discussion);
             $discussion->canreply = forum_user_can_post($forum, $discussion, $USER, $cm, $course, $modcontext);
             if (forum_is_author_hidden($discussion, $forum)) {
                 $discussion->userid = null;
                 $discussion->userfullname = null;
                 $discussion->userpictureurl = null;
                 $discussion->usermodified = null;
                 $discussion->usermodifiedfullname = null;
//.........这里部分代码省略.........

 /**
  * Returns a list of forum discussions as well as a summary of the discussion
  * in a provided list of forums.
  *
  * @param array $forumids the forum ids
  * @return array the forum discussion details
  * @since Moodle 2.5
  */
 public static function get_forum_discussions($forumids)
 {
     global $CFG, $DB, $USER;
     require_once $CFG->dirroot . "/mod/forum/lib.php";
     // Validate the parameter.
     $params = self::validate_parameters(self::get_forum_discussions_parameters(), array('forumids' => $forumids));
     $forumids = $params['forumids'];
     // Array to store the forum discussions to return.
     $arrdiscussions = array();
     // Keep track of the users we have looked up in the DB.
     $arrusers = array();
     // Loop through them.
     foreach ($forumids as $id) {
         // Get the forum object.
         $forum = $DB->get_record('forum', array('id' => $id), '*', MUST_EXIST);
         $course = get_course($forum->course);
         $modinfo = get_fast_modinfo($course);
         $forums = $modinfo->get_instances_of('forum');
         $cm = $forums[$forum->id];
         // Get the module context.
         $modcontext = context_module::instance($cm->id);
         // Validate the context.
         self::validate_context($modcontext);
         require_capability('mod/forum:viewdiscussion', $modcontext);
         // Get the discussions for this forum.
         $params = array();
         $groupselect = "";
         $groupmode = groups_get_activity_groupmode($cm, $course);
         if ($groupmode and $groupmode != VISIBLEGROUPS and !has_capability('moodle/site:accessallgroups', $modcontext)) {
             // Get all the discussions from all the groups this user belongs to.
             $usergroups = groups_get_user_groups($course->id);
             if (!empty($usergroups['0'])) {
                 list($sql, $params) = $DB->get_in_or_equal($usergroups['0']);
                 $groupselect = "AND (groupid {$sql} OR groupid = -1)";
             }
         }
         array_unshift($params, $id);
         $select = "forum = ? {$groupselect}";
         if ($discussions = $DB->get_records_select('forum_discussions', $select, $params, 'timemodified DESC')) {
             // Check if they can view full names.
             $canviewfullname = has_capability('moodle/site:viewfullnames', $modcontext);
             // Get the unreads array, this takes a forum id and returns data for all discussions.
             $unreads = array();
             if ($cantrack = forum_tp_can_track_forums($forum)) {
                 if ($forumtracked = forum_tp_is_tracked($forum)) {
                     $unreads = forum_get_discussions_unread($cm);
                 }
             }
             // The forum function returns the replies for all the discussions in a given forum.
             $replies = forum_count_discussion_replies($id);
             foreach ($discussions as $discussion) {
                 // This function checks capabilities, timed discussions, groups and qanda forums posting.
                 if (!forum_user_can_see_discussion($forum, $discussion, $modcontext)) {
                     continue;
                 }
                 $usernamefields = user_picture::fields();
                 // If we don't have the users details then perform DB call.
                 if (empty($arrusers[$discussion->userid])) {
                     $arrusers[$discussion->userid] = $DB->get_record('user', array('id' => $discussion->userid), $usernamefields, MUST_EXIST);
                 }
                 // Get the subject.
                 $subject = $DB->get_field('forum_posts', 'subject', array('id' => $discussion->firstpost), MUST_EXIST);
                 // Create object to return.
                 $return = new stdClass();
                 $return->id = (int) $discussion->id;
                 $return->course = $discussion->course;
                 $return->forum = $discussion->forum;
                 $return->name = $discussion->name;
                 $return->userid = $discussion->userid;
                 $return->groupid = $discussion->groupid;
                 $return->assessed = $discussion->assessed;
                 $return->timemodified = (int) $discussion->timemodified;
                 $return->usermodified = $discussion->usermodified;
                 $return->timestart = $discussion->timestart;
                 $return->timeend = $discussion->timeend;
                 $return->firstpost = (int) $discussion->firstpost;
                 $return->firstuserfullname = fullname($arrusers[$discussion->userid], $canviewfullname);
                 $return->firstuserimagealt = $arrusers[$dis