1 files changed, 51 insertions, 0 deletions
diff --git a/lib/PublicInbox/MsgTime.pm b/lib/PublicInbox/MsgTime.pm
new file mode 100644
index 00000000..87664f4b
--- /dev/null
+++ b/lib/PublicInbox/MsgTime.pm
@@ -0,0 +1,51 @@
+# Copyright (C) 2018 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+package PublicInbox::MsgTime;
+use strict;
+use warnings;
+use base qw(Exporter);
+our @EXPORT_OK = qw(msg_timestamp);
+use Date::Parse qw(str2time);
+use Time::Zone qw(tz_offset);
+
+sub msg_timestamp ($) {
+        my ($hdr) = @_; # Email::MIME::Header
+        my ($ts, $zone);
+        my $mid;
+        my @recvd = $hdr->header_raw('Received');
+        foreach my $r (@recvd) {
+                $zone = undef;
+                $r =~ /\s*(\d+\s+[[:alpha:]]+\s+\d{2,4}\s+
+                        \d+\D\d+(?:\D\d+)\s+([\+\-]\d+))/sx or next;
+                $zone = $2;
+                $ts = eval { str2time($1) } and last;
+                $mid ||= $hdr->header_raw('Message-ID');
+                warn "no date in $mid Received: $r\n";
+        }
+        unless (defined $ts) {
+                my @date = $hdr->header_raw('Date');
+                foreach my $d (@date) {
+                        $zone = undef;
+                        $ts = eval { str2time($d) };
+                        if ($@) {
+                                $mid ||= $hdr->header_raw('Message-ID');
+                                warn "bad Date: $d in $mid: $@\n";
+                        } elsif ($d =~ /\s+([\+\-]\d+)\s*\z/) {
+                                $zone = $1;
+                        }
+                }
+        }
+        $ts = time unless defined $ts;
+        return $ts unless wantarray;
+
+        $zone ||= '+0000';
+        # "-1200" is the furthest westermost zone offset,
+        # but git fast-import is liberal so we use "-1400"
+        if ($zone >= 1400 || $zone <= -1400) {
+                warn "bogus TZ offset: $zone, ignoring and assuming +0000\n";
+                $zone = '+0000';
+        }
+        ($ts, $zone);
+}
+
+1;