%# BEGIN LICENSE BLOCK
%# 
%#  Copyright (c) 2002-2003 Jesse Vincent <jesse@bestpractical.com>
%#  
%#  This program is free software; you can redistribute it and/or modify
%#  it under the terms of version 2 of the GNU General Public License 
%#  as published by the Free Software Foundation.
%# 
%#  A copy of that license should have arrived with this
%#  software, but in any event can be snarfed from www.gnu.org.
%# 
%#  This program 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.
%# 
%# END LICENSE BLOCK

<& /RTFM/Elements/Tabs, current_toptab => "RTFM/Topics.html", Title => loc('Topic hierarchy'), class => $class, topic => $id &>

<& /Elements/ListActions, actions => \@Actions &>
<a href="Topics.html">Root</a>
% if (defined $class) {
&gt; <a href="Topics.html?class=<%$currclass->Id%>"><% $currclass->Name %></a>
% }

% if ($id != 0) {
&gt; <& /RTFM/Elements/ShowTopic, topic => $currtopic &>
% }
<br />
<& /Elements/TitleBoxStart, title => loc('Topics') &>
<ul>
<%perl>
if ($class) {
    print MakeLinks(undef, $currclass);
    ProduceTree(\@Actions, $currclass, 0, $id);
} else {
    while (my $c = $Classes->Next) {
	print MakeLinks(undef, $c);
	ProduceTree(\@Actions, $c, 0, $id);
    }
}
</%perl>
</ul>
<& /Elements/TitleBoxEnd &>

% if ($id || $showall) {
%# TODO: Eventually it would be nice to show all for classes too.  Thus
%# the condition above.
<br/>
<& /Elements/TitleBoxStart, title => loc('Articles') &>
<%perl>
my $Articles = RT::FM::ObjectTopicCollection->new($session{'CurrentUser'});
$Articles->Limit(FIELD => 'ObjectType', VALUE => 'RT::FM::Article');
if ($id) {
    $Articles->Limit(FIELD => 'Topic', VALUE => $id, ENTRYAGGREGATOR => 'OR');
    if ($showall) {
        my $kids = $currtopic->Children;
	while (my $k = $kids->Next) {
	    $Articles->Limit(FIELD => 'Topic', VALUE => $k->Id,
	                     ENTRYAGGREGATOR => 'OR');
	}
    }
}
if ($Articles->Count) {
</%perl>
<ul>
% while (my $obj = $Articles->Next) {
%   my $a = RT::FM::Article->new($session{'CurrentUser'});
%   $a->Load($obj->ObjectId);
<li><a href="Article/Display.html?id=<% $a->Id %>"><% $a->Name %></a></li>
% }
</ul>
% } else {
<i>No articles in this topic</i>
% }
<& /Elements/TitleBoxEnd &>
% }


<%init>
my @Actions;
my $Classes;
my $currclass;
my $currtopic;

if ($class) {
    $currclass = RT::FM::Class->new($session{'CurrentUser'});
    $currclass->Load($class);
} else {
    $Classes = RT::FM::ClassCollection->new($session{'CurrentUser'});
    $Classes->UnLimit;
}

if ($id) {
    $currtopic = RT::FM::Topic->new($session{'CurrentUser'});
    $currtopic->Load($id);
}

# A subroutine that iterates through topics and their children, producing
# the necessary ul, li, and href links for the table of contents.  Thank
# heaven for query caching.  The $restrict variable is used to display only
# the branch of the hierarchy which contains that topic ID.

sub ProduceTree {
    my ($Actions, $c, $parentid, $restrictid) = @_;
    $parentid = 0 unless $parentid;

    # Deal with tree restriction, if any.
    if ($restrictid) {
        my $rtopic = RT::FM::Topic->new($session{'CurrentUser'});
	$rtopic->Load($restrictid);
	unless ($rtopic->Id() &&
	        $rtopic->ObjectId() == $c->Id) {
	    push(@{$Actions}, "Could not restrict view to topic $restrictid");
	    # Start over, without the restriction.
	    &ProduceTree($Actions, $c, $parentid, undef);
	} else {
	    my @showtopics;
	    push(@showtopics, $rtopic);
	    my $parent = $rtopic->ParentObj;
	    while ($parent->Id) {
		push(@showtopics, $parent);
		my $newparent = $parent->ParentObj;
		$parent = $newparent;
	    }
	    
	    # List the topics.
	    while (my $t = pop @showtopics) {
		print "<ul>";
		print &MakeLinks($t, $c, $t->Children->Count);
		if ($t->Id == $restrictid) {
		    &ProduceTree($Actions, $c, $restrictid, undef);
		}
	    }
	    print "</ul>" x scalar(@showtopics);
	}
    } else {
	# No restriction in place.  Build the entire tree.
	my $topics = RT::FM::TopicCollection->new($session{'CurrentUser'});
	$topics->LimitToObject($c);
	$topics->LimitToKids($parentid);
	while (my $t = $topics->Next) {
	    print "<ul>";
	    if ($t->Children->Count) {
		print &MakeLinks($t, $c, 1);
		&ProduceTree($Actions, $c, $t->Id);
	    } else {
		print &MakeLinks($t, $c, 0);
	    }
	    print "</ul>\n";
	}
    }
}

sub MakeLinks {
    my ($topic, $c, $haschild) = @_;
    my $query;
    my $output;

    if (ref($topic) eq 'RT::FM::Topic') {
	if ($haschild) {
	    $query = "Topics.html?id=" . $topic->Id . "&class=" . $c->Id;
	} else {
	    $query = "Topics.html?id=" . $topic->Id . "&class=" . $c->Id .
		"&showall=1";
	}
	
	$output = "<li><a href=\"$query\">" . $topic->Name();
	$output .= ": " . $topic->Description() if $topic->Description();
	$output .= "</a>";
	
	if ($haschild) {
	    $output .= " &nbsp;&nbsp;&nbsp;[ <a href=\"$query&showall=1\">Show all articles</a> ]";
	}
	
	$output .= "</li>\n";
	
    } else {
	# This builds a link for the class specified, with no particular
	# topic.
	$query = "Topics.html?class=" . $c->Id;
	$output = "<li><a href=\"$query\">" . $c->Name . "</a>";
	$output .= ": " . $c->Description if $c->Description;
    }
    
    return $output;
}

</%init>

<%args>
$id => 0
$class => undef
$showall => undef
</%args>