www: improve navigation around contemporary threads

Sometimes it's useful to quickly get to threads and messages
which are contemporaries of the current thread/message being
focused on.  This hopefully improves navigation by making:

a) the top line (where $INBOX_DIR/description) is shown
   a link to the latest topics in search results and
   per-thread/per-message views.

b) providing a link to contemporaries ("~YYYY-MM-DD") at
   around the thread overview skeleton area for per-thread
   and per-message views

1 files changed, 8 insertions, 1 deletions

diff --git a/lib/PublicInbox/Hval.pm b/lib/PublicInbox/Hval.pm
index e21a64a6..fb21041a 100644
--- a/lib/PublicInbox/Hval.pm
+++ b/lib/PublicInbox/Hval.pm
@@ -10,7 +10,8 @@ use Encode qw(find_encoding);
 use PublicInbox::MID qw/mid_clean mid_escape/;
 use base qw/Exporter/;
 our @EXPORT_OK = qw/ascii_html obfuscate_addrs to_filename src_escape
-                to_attr prurl mid_href/;
+                to_attr prurl mid_href fmt_ts ts2str/;
+use POSIX qw(strftime);
 my $enc_ascii = find_encoding('us-ascii');
 
 # safe-ish acceptable filename pattern for portability
@@ -123,4 +124,10 @@ sub to_attr ($) {
         $first . $str;
 }
 
+# for the t= query parameter passed to overview DB
+sub ts2str ($) { strftime('%Y%m%d%H%M%S', gmtime($_[0])) };
+
+# human-friendly format
+sub fmt_ts ($) { strftime('%Y-%m-%d %k:%M', gmtime($_[0])) }
+
 1;