- my @mids = (join(' ', @raw) =~ /<([^>]+)>/g);
- my $mids = scalar(@mids) == 0 ? \@raw: \@mids;
+ uniq_mids(\@mids);
+}
+
+# last References should be IRT, but some mail clients do things
+# out of order, so trust IRT over References iff IRT exists
+sub references ($) {
+ my ($hdr) = @_;
+ my @mids;
+ foreach my $f (qw(References In-Reply-To)) {
+ my @v = $hdr->header_raw($f);
+ foreach my $v (@v) {
+ push(@mids, ($v =~ /<([^>]+)>/sg));
+ }
+ }
+
+ # old versions of git-send-email would prompt users for
+ # In-Reply-To and users' muscle memory would use 'y' or 'n'
+ # as responses:
+ my %addr = ( y => 1, n => 1 );
+
+ foreach my $f (qw(To From Cc)) {
+ my @v = $hdr->header_raw($f);
+ foreach my $v (@v) {
+ $addr{$_} = 1 for (PublicInbox::Address::emails($v));
+ }
+ }
+ uniq_mids(\@mids, \%addr);
+}
+
+sub uniq_mids ($;$) {
+ my ($mids, $seen) = @_;