view: fix topic threading when ghosts are present

This fixes a bug where a message replying to a ghost would
accidentally be added to the wrong topic in the index/topic
view.

Before commit 76d8f68dc273e54809ad69cfe49e141003f790ef ("view:
avoid recursion in topic index"), we would refuse to indent a
topic which started with a ghost which hid the problem.  Now we
inform the user the thread started elsewhere.

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 8e81391e106e67584527b8fa17287f3cc16a3ecb..8d2e5424428a953ca74a1a1c157ead60b78f76c0 100644 (file)
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -748,8 +748,7 @@ sub sort_ts {
 }
 
 sub _tryload_ghost ($$) {
-       my ($srch, $node) = @_;
-       my $mid = $node->messageid;
+       my ($srch, $mid) = @_;
        my $smsg = $srch->lookup_mail($mid) or return;
        $smsg->mini_mime;
 }
@@ -758,30 +757,25 @@ sub _tryload_ghost ($$) {
 # returns 1 if done, undef if not
 sub add_topic {
        my ($state, $level, $node) = @_;
-       my $child_adjust = 1;
        my $srch = $state->{srch};
-       my $x = $node->message || _tryload_ghost($srch, $node);
+       my $mid = $node->messageid;
+       my $x = $node->message || _tryload_ghost($srch, $mid);
+       my ($subj, $ts);
        if ($x) {
                $x = $x->header_obj;
-               my $subj;
-
                $subj = $x->header('Subject');
                $subj = $srch->subject_normalized($subj);
-
-               if (++$state->{subjs}->{$subj} == 1) {
-                       push @{$state->{order}}, [ $level, $subj ];
-               }
-
-               my $mid = mid_clean($x->header_raw('Message-ID'));
-
-               my $ts = $x->header('X-PI-TS');
-               my $exist = $state->{latest}->{$subj};
-               if (!$exist || $exist->[1] < $ts) {
-                       $state->{latest}->{$subj} = [ $mid, $ts ];
-               }
-       } else {
-               # ghost message, do not bump level
-               $child_adjust = 0;
+               $ts = $x->header('X-PI-TS');
+       } else { # ghost message, do not bump level
+               $ts = -666;
+               $subj = "<$mid>";
+       }
+       if (++$state->{subjs}->{$subj} == 1) {
+               push @{$state->{order}}, [ $level, $subj ];
+       }
+       my $exist = $state->{latest}->{$subj};
+       if (!$exist || $exist->[1] < $ts) {
+               $state->{latest}->{$subj} = [ $mid, $ts ];
        }
 }
 
@@ -802,7 +796,6 @@ sub emit_topics {
                my $n = delete $subjs->{$subj};
                my ($mid, $ts) = @{delete $latest->{$subj}};
                $mid = PublicInbox::Hval->new_msgid($mid)->as_href;
-               $subj = PublicInbox::Hval->new($subj)->as_html;
                $pfx = indent_for($level);
                my $nl = $level == $prev ? "\n" : '';
                if ($nl && $cur) {
@@ -811,10 +804,14 @@ sub emit_topics {
                }
                $cur ||= [ $ts, '' ];
                $cur->[0] = $ts if $ts > $cur->[0];
-               $cur->[1] .= $nl . $pfx . th_pfx($level) .
-                               "<a\nhref=\"$mid/t/#u\"><b>" .
-                               $subj . "</b></a>\n";
+               $cur->[1] .= $nl . $pfx . th_pfx($level);
+               if ($ts == -666) { # ghost
+                       $cur->[1] .= ghost_parent('', $mid) . "\n";
+                       next; # child will have mbox / atom link
+               }
 
+               $subj = PublicInbox::Hval->new($subj)->as_html;
+               $cur->[1] .= "<a\nhref=\"$mid/t/#u\"><b>$subj</b></a>\n";
                $ts = fmt_ts($ts);
                my $attr = " $ts UTC";