view: reply threading adjustment

Give changes in subject their own line to reduce line wrapping,
but avoid showing any redundant subjects by maintaining a hash
of subjects already displayed.

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index dcdb310991dabfd43b127e5d6bba99cb9d2e2533..fe4f2dfd9c6bd907c3c7d592971fb225ac3cd145 100644 (file)
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -9,6 +9,7 @@ use Encode::MIME::Header;
 use Email::MIME::ContentType qw/parse_content_type/;
 use PublicInbox::Hval;
 use PublicInbox::MID qw/mid_clean mid_compressed/;
+use Digest::SHA;
 require POSIX;
 
 # TODO: make these constants tunable
@@ -393,37 +394,45 @@ sub anchor_for {
 
 sub simple_dump {
        my ($dst, $root, $node, $level) = @_;
-       $$dst .= '  ' x $level;
+       my $pfx = '  ' x $level;
+       $$dst .= $pfx;
        if (my $x = $node->message) {
                my $mid = $x->header('Message-ID');
                if ($root->[0] ne $mid) {
-                       my $s = clean_subj($x->header('Subject'));
-                       if ($root->[1] eq $s) {
-                               $s = '  ';
+                       my $s = $x->header('Subject');
+                       my $h = hash_subj($s);
+                       if ($root->[1]->{$h}) {
+                               $s = '';
                        } else {
+                               $root->[1]->{$h} = 1;
                                $s = PublicInbox::Hval->new($s);
-                               $s = $s->as_html . ' ';
+                               $s = $s->as_html;
                        }
                        my $m = PublicInbox::Hval->new_msgid($mid);
                        my $f = PublicInbox::Hval->new($x->header('X-PI-From'));
                        my $d = PublicInbox::Hval->new($x->header('X-PI-Date'));
                        $m = $m->as_href . '.html';
                        $f = $f->as_html;
-                       $d = $d->as_html;
-                       $$dst .= "` <a\nhref=\"$m\">$s$f @ $d UTC</a>\n";
+                       $d = $d->as_html . ' UTC';
+                       if (length($s) == 0) {
+                               $$dst .= "` <a\nhref=\"$m\">$f @ $d</a>\n";
+                       } else {
+                               $$dst .= "` <a\nhref=\"$m\">$s</a>\n" .
+                                    "$pfx  by $f @ $d\n";
+                       }
                }
        }
        simple_dump($dst, $root, $node->child, $level + 1) if $node->child;
        simple_dump($dst, $root, $node->next, $level) if $node->next;
 }
 
-sub clean_subj {
+sub hash_subj {
        my ($subj) = @_;
        $subj =~ s/\A\s+//;
        $subj =~ s/\s+\z//;
        $subj =~ s/^(?:re|aw):\s*//i; # remove reply prefix (aw: German)
        $subj =~ s/\s+/ /;
-       $subj;
+       Digest::SHA::sha1($subj);
 }
 
 sub thread_replies {
@@ -435,7 +444,7 @@ sub thread_replies {
        $th->thread;
        $th->order(*PublicInbox::Thread::sort_ts);
        $root = [ $root->header('Message-ID'),
-                 clean_subj($root->header('Subject')) ];
+                 { hash_subj($root->header('Subject')) => 1 } ];
        simple_dump($dst, $root, $_, 0) for $th->rootset;
 }