use both Date: and Received: times

We want to rely on Date: to sort messages within individual
threads since it keeps messages from git-send-email(1) sorted.
However, since developers occasionally have the clock set
wrong on their machines, sort overall messages by the newest
date in a Received: header so the landing page isn't forever
polluted by messages from the future.

This also gives us determinism for commit times in most cases,
as we'll used the Received: timestamp there, as well.

1 files changed, 3 insertions, 2 deletions

diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 7e7c989d..f08b9870 100644
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -8,11 +8,12 @@ use strict;
 use warnings;
 
 # values for searching
-use constant TS => 0; # timestamp
+use constant DS => 0; # Date: header in Unix time
 use constant NUM => 1; # NNTP article number
 use constant BYTES => 2; # :bytes as defined in RFC 3977
 use constant LINES => 3; # :lines as defined in RFC 3977
-use constant YYYYMMDD => 4; # for searching in the WWW UI
+use constant TS => 4;  # Received: header in Unix time
+use constant YYYYMMDD => 5; # for searching in the WWW UI
 
 use Search::Xapian qw/:standard/;
 use PublicInbox::SearchMsg;