miscsearch: implement ->newsgroup_matches

This may be used to speed up newsgroup searches down-the-line,
but the grep perlop isn't too shabby, at the moment.

1 files changed, 40 insertions, 0 deletions

diff --git a/lib/PublicInbox/MiscSearch.pm b/lib/PublicInbox/MiscSearch.pm
index 48ef6914..f2e31443 100644
--- a/lib/PublicInbox/MiscSearch.pm
+++ b/lib/PublicInbox/MiscSearch.pm
@@ -76,6 +76,46 @@ sub mset {
         retry_reopen($self, \&misc_enquire_once, $qr, $opt);
 }
 
+sub ibx_matches_once { # retry_reopen callback
+        my ($self, $qr, $by_newsgroup) = @_;
+        # double in case no newsgroups are configured:
+        my $limit = scalar(keys %$by_newsgroup) * 2;
+        my $opt = { limit => $limit, offset => 0, relevance => -1 };
+        my $ret = {}; # newsgroup => $ibx of matches
+        while (1) {
+                my $mset = misc_enquire_once($self, $qr, $opt);
+                for my $mi ($mset->items) {
+                        my $doc = $mi->get_document;
+                        my $end = $doc->termlist_end;
+                        my $cur = $doc->termlist_begin;
+                        $cur->skip_to('Q');
+                        if ($cur != $end) {
+                                my $ng = $cur->get_termname; # eidx_key
+                                $ng =~ s/\AQ// or warn "BUG: no `Q': $ng";
+                                if (my $ibx = $by_newsgroup->{$ng}) {
+                                        $ret->{$ng} = $ibx;
+                                }
+                        } else {
+                                warn <<EOF;
+W: docid=${\$mi->get_docid} has no `Q' (eidx_key) term
+EOF
+                        }
+                }
+                my $nr = $mset->size;
+                return $ret if $nr < $limit;
+                $opt->{offset} += $nr;
+        }
+}
+
+# returns a newsgroup => PublicInbox::Inbox mapping
+sub newsgroup_matches {
+        my ($self, $qs, $pi_cfg) = @_;
+        my $qp = $self->{qp} //= mi_qp_new($self);
+        $qs .= ' type:inbox';
+        my $qr = $qp->parse_query($qs, $PublicInbox::Search::QP_FLAGS);
+        retry_reopen($self, \&ibx_matches_once, $qr, $pi_cfg->{-by_newsgroup});
+}
+
 sub ibx_data_once {
         my ($self, $ibx) = @_;
         my $xdb = $self->{xdb};