<?PHP  // $Id$

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

    optional_variable($id);            // Course Module ID
    optional_variable($f);             // Forum ID
    optional_variable($mode);          // Display mode (for single forum)
    optional_variable($search, "");    // search string
    optional_variable($showall, "");   // show all discussions on one page

    $strforums = get_string("modulenameplural", "forum");
    $strforum = get_string("modulename", "forum");

    if ($id) {
        if (! $cm = get_record("course_modules", "id", $id)) {
            error("Course Module ID was incorrect");
        }
        if (! $course = get_record("course", "id", $cm->course)) {
            error("Course is misconfigured");
        }
        if (! $forum = get_record("forum", "id", $cm->instance)) {
            error("Forum ID was incorrect");
        }
        $buttontext = update_module_button($cm->id, $course->id, $strforum);

    } else if ($f) {
        if (! $forum = get_record("forum", "id", $f)) {
            error("Forum ID was incorrect or no longer exists");
        }
        if (! $course = get_record("course", "id", $forum->course)) {
            error("Forum is misconfigured - don't know what course it's from");
        }
        if ($cm = get_coursemodule_from_instance("forum", $forum->id, $course->id)) {
            $buttontext = update_module_button($cm->id, $course->id, $strforum);
        } else {
            $buttontext = "";
        }

    } else {
        error("Must specify a course module or a forum ID");
    }

    if (!$buttontext) {
        $buttontext = forum_print_search_form($course, $search, true, "plain");
    } 

    if ($course->category) {
        require_login($course->id);
        $navigation = "<A HREF=\"../../course/view.php?id=$course->id\">$course->shortname</A> ->
                       <A HREF=\"index.php?id=$course->id\">$strforums</A> ->";
    } else {
        $navigation = "<A HREF=\"index.php?id=$course->id\">$strforums</A> ->";
    }

    if ($forum->type == "teacher") {
        if (!isteacher($course->id)) {
            error("You must be a $course->teacher to view this forum");
        }
    }

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

    print_header("$course->shortname: $forum->name", "$course->fullname",
                 "$navigation $forum->name", "", "", true, $buttontext, navmenu($course, $cm));

    if (!$cm->visible and !isteacher($course->id)) {
        notice(get_string("activityiscurrentlyhidden"));
    }

    if ($USER) {
        $SESSION->fromdiscussion = "$FULLME";
        if (forum_is_forcesubscribed($forum->id)) {
            $streveryoneissubscribed = get_string("everyoneissubscribed", "forum");
            $strallowchoice = get_string("allowchoice", "forum");
            echo "<div align=right>";
            helpbutton("subscription", $streveryoneissubscribed, "forum");
            echo "<font size=1>";
            if (isteacher($course->id)) {
                echo "<a title=\"$strallowchoice\" href=\"subscribe.php?id=$forum->id&force=no\">$streveryoneissubscribed</a>";
            } else {
                echo $streveryoneissubscribed;
            }
            echo "</font></div>";

        } else {
            $streveryonecanchoose = get_string("everyonecanchoose", "forum");
            $strforcesubscribe = get_string("forcesubscribe", "forum");
            $strshowsubscribers = get_string("showsubscribers", "forum");

            echo "<div align=right>";
            helpbutton("subscription", $streveryonecanchoose, "forum");
            echo "<font size=1>";

            if (isteacher($course->id)) {
                echo "<a title=\"$strforcesubscribe\" href=\"subscribe.php?id=$forum->id&force=yes\">$streveryonecanchoose</a>";
                echo "</font></div><div align=right><font size=1>";
                echo "<a href=\"subscribers.php?id=$forum->id\">$strshowsubscribers</a>";
            } else {
                echo $streveryonecanchoose;
            }
            echo "</font></div>";

            if (forum_is_subscribed($USER->id, $forum->id)) {
                $subtexttitle = get_string("subscribestop", "forum");
                $subtext = get_string("unsubscribe", "forum");
            } else {
                $subtexttitle = get_string("subscribestart", "forum");
                $subtext = get_string("subscribe", "forum");
            }
            echo "<div align=right>";
            echo "<font size=1><a title=\"$subtexttitle\" href=\"subscribe.php?id=$forum->id\">$subtext</a></font>";
            echo "</div>";
        }
    }


    switch ($forum->type) {
        case "single":
            if (! $discussion = get_record("forum_discussions", "forum", $forum->id)) {
                if ($discussions = get_records("forum_discussions", "forum", $forum->id, "timemodified ASC")) {
                    notify("Warning! There is more than one discussion in this forum - using the most recent");
                    $discussion = array_pop($discussions);
                } else {
                    error("Could not find the discussion in this forum");
                }
            }
            if (! $post = forum_get_post_full($discussion->firstpost)) {
                error("Could not find the first post in this forum");
            }
            forum_set_display_mode($mode);
            forum_print_discussion($course, $forum, $discussion, $post, $USER->mode);
            break;

        case "eachuser":
            if (!empty($forum->intro)) {
                print_simple_box(text_to_html($forum->intro), "center");
            }
            echo "<p align=\"center\">";
            if (forum_user_can_post_discussion($forum)) {
                print_string("allowsdiscussions", "forum");
            } else {
                echo "&nbsp";
            }
            echo "</p>";
            if (!empty($showall)) {
                forum_print_latest_discussions($forum->id, 0, "header");
            } else {
                forum_print_latest_discussions($forum->id, $CFG->forum_manydiscussions, "header");
            }
            break;

        case "teacher":
            if (!empty($showall)) {
                forum_print_latest_discussions($forum->id, 0, "header");
            } else {
                forum_print_latest_discussions($forum->id, $CFG->forum_manydiscussions, "header");
            }
            break;

        default:
            if (!empty($forum->intro)) {
                print_simple_box(text_to_html($forum->intro), "center");
            }
            echo "<p>&nbsp;</p>";
            if (!empty($showall)) {
                forum_print_latest_discussions($forum->id, 0, "header");
            } else {
                forum_print_latest_discussions($forum->id, $CFG->forum_manydiscussions, "header");
            }
            break;
    }


    print_footer($course);

?>