<?PHP  // $Id: subscribers.php,v 1.19 2004/08/21 20:20:55 gustav_delius Exp $

    require_once("../../config.php");
    require_once("lib.php");

    require_variable($id);                // forum
    optional_variable($group);            // change of group
    
    optional_variable($edit);     // Turn editing on and off

    if (! $forum = get_record("forum", "id", $id)) {
        error("Forum ID is incorrect");
    }

    if (! $course = get_record("course", "id", $forum->course)) {
        error("Could not find this course!");
    }

    if (! $cm = get_coursemodule_from_instance("forum", $forum->id, $course->id)) {
        $cm->id = 0;
    }

    require_login($course->id);

    if (!isteacher($course->id)) {
        error("This page is for teachers only");
    }

    unset($SESSION->fromdiscussion);

    add_to_log($course->id, "forum", "view subscribers", "subscribers.php?id=$forum->id", $forum->id, $cm->id);
    
    if (isset($_GET['edit'])) {
        if($edit == "on") {
            $USER->subscriptionsediting = true;
        } else {
            $USER->subscriptionsediting = false;
        }
    }

    $strsubscribeall = get_string("subscribeall", "forum");
    $strsubscribenone = get_string("subscribenone", "forum");
    $strsubscribers = get_string("subscribers", "forum");
    $strforums      = get_string("forums", "forum");

    $navigation = "<a href=\"index.php?id=$course->id\">$strforums</a> -> 
       <a href=\"view.php?f=$forum->id\">$forum->name</a> -> $strsubscribers";

    print_header_simple("$strsubscribers", "", "$navigation", 
        "", "", true, forum_update_subscriptions_button($course->id, $id));

/// Check to see if groups are being used in this forum
    if ($groupmode = groupmode($course, $cm)) {   // Groups are being used
        $currentgroup = setup_and_print_groups($course, $groupmode, "subscribers.php?id=$forum->id");
    } else {
        $currentgroup = false;
    }

    if (empty($USER->subscriptionsediting)) {         /// Display an overview of subscribers
        
        if (! $users = forum_subscribed_users($course, $forum, $currentgroup) ) {
    
            print_heading(get_string("nosubscribers", "forum"));
    
        } else {
    
            print_heading(get_string("subscribersto","forum", "'$forum->name'"));
    
            echo '<table align="center" cellpadding="5" cellspacing="5">';
            foreach ($users as $user) {
                echo "<tr><td>";
                print_user_picture($user->id, $course->id, $user->picture);
                echo "</td><td bgcolor=\"$THEME->cellcontent\">";
                echo fullname($user);
                echo "</td><td bgcolor=\"$THEME->cellcontent\">";
                echo "$user->email";
                echo "</td></tr>";
            }
            echo "</table>";
        }
    
        print_footer($course);
        exit;
    }

/// We are in editing mode.

    $strexistingsubscribers   = get_string("existingsubscribers", 'forum');
    $strpotentialsubscribers  = get_string("potentialsubscribers", 'forum');
    $straddsubscriber    = get_string("addsubscriber", 'forum');
    $strremovesubscriber = get_string("removesubscriber", 'forum');
    $strsearch        = get_string("search");
    $strsearchresults  = get_string("searchresults");
    $strshowall = get_string("showall");
    $strsubscribers = get_string("subscribers", "forum");
    $strforums      = get_string("forums", "forum");

    if ($frm = data_submitted()) {

/// A form was submitted so process the input

        if (!empty($frm->add) and !empty($frm->addselect)) {

            foreach ($frm->addselect as $addsubscriber) {
                if (! forum_subscribe($addsubscriber, $id)) {
                    error("Could not add subscriber with id $addsubscriber to this forum!");
                }
            }
        } else if (!empty($frm->remove) and !empty($frm->removeselect)) {
            foreach ($frm->removeselect as $removesubscriber) {
                if (! forum_unsubscribe($removesubscriber, $id)) {
                    error("Could not remove subscriber with id $removesubscriber from this forum!");
                }
            }
        } else if (!empty($frm->showall)) {
            unset($frm->searchtext);
            $frm->previoussearch = 0;
        }
    }

    $previoussearch = (!empty($frm->search) or ($frm->previoussearch == 1)) ;

/// Get all existing subscribers for this forum.
    if (!$subscribers = forum_subscribed_users($course, $forum, $currentgroup)) {
        $subscribers = array();
    }
    
    $subscriberarray = array();
    foreach ($subscribers as $subscriber) {
        $subscriberarray[] = $subscriber->id;
    }
    $subscriberlist = implode(',', $subscriberarray);
    
    unset($subscriberarray);

/// Get search results excluding any users already subscribed

    if (!empty($frm->searchtext) and $previoussearch) {
        $searchusers = search_users($course->id, $currentgroup, $frm->searchtext, 'firstname ASC, lastname ASC', $subscriberlist);
    }
    
/// If no search results then get potential subscribers for this forum excluding users already subscribed
    if (empty($searchusers)) {
        if ($currentgroup) {
            $users = get_group_users($currentgroup, 'firstname ASC, lastname ASC', $subscriberlist);
        } else {
             $users = get_course_users($course->id, 'firstname ASC, lastname ASC', $subscriberlist);
        }
        if (!$users) {
            $users = array();
        }

    }

    $searchtext = (isset($frm->searchtext)) ? $frm->searchtext : "";
    $previoussearch = ($previoussearch) ? '1' : '0';

    print_simple_box_start("center", "", "$THEME->cellheading");

    include('subscriber.html');

    print_simple_box_end();

    print_footer();

?>
