lib/PublicInbox/SearchView.pm - pub/scm/infra/public-inbox - Git at Google

 # Copyright (C) all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 #
 # Displays search results for the web interface
 package PublicInbox::SearchView;
 use strict;
 use v5.10.1;
 use List::Util qw(min max);
 use URI::Escape qw(uri_unescape);
 use PublicInbox::Smsg;
 use PublicInbox::Hval qw(ascii_html obfuscate_addrs mid_href fmt_ts);
 use PublicInbox::View;
 use PublicInbox::WwwAtomStream;
 use PublicInbox::WwwStream qw(html_oneshot);
 use PublicInbox::SearchThread;
 use PublicInbox::SearchQuery;
 use PublicInbox::Search qw(get_pct);
 my %rmap_inc;

 sub mbox_results {
 	my ($ctx) = @_;
 	my $q = PublicInbox::SearchQuery->new($ctx->{qp});
 	if ($ctx->{env}->{'psgi.input'}->read(my $buf, 3)) {
 		$q->{t} = 1 if $buf =~ /\Ax=[^0]/;
 	}
 	require PublicInbox::Mbox;
 	$q->{x} eq 'm' ? PublicInbox::Mbox::mbox_all($ctx, $q) :
 			sres_top_html($ctx);
 }

 sub sres_top_html {
 	my ($ctx) = @_;
 	my $srch = $ctx->{srch} = $ctx->{ibx}->isrch or
 		return PublicInbox::WWW::need($ctx, 'Search');
 	my $q = PublicInbox::SearchQuery->new($ctx->{qp});
 	PublicInbox::View::addr2urlmap $ctx if $q->{x} eq 't';
 	my $o = $q->{o} // 0;
 	my $asc;
 	if ($o < 0) {
 		$asc = 1;
 		$o = -($o + 1); # so [-1] is the last element, like Perl lists
 	}

 	# double the limit for expanded views:
 	my $opt = {
 		limit => $q->{l},
 		offset => $o,
 		relevance => $q->{r},
 		threads => $q->{t},
 		asc => $asc,
 	};
 	my $qs = $q->{'q'};
 	$srch->query_approxidate($ctx->{ibx}->git, $qs);
 	sub {
 		$ctx->{wcb} = $_[0]; # PSGI server supplied write cb
 		$srch->async_mset($qs, $opt, \&sres_html_cb, $ctx, $opt, $q);
 	}
 }

 sub sres_html_cb { # async_mset cb
 	my ($ctx, $opt, $q, $mset, $err) = @_;
 	my $code = 200;
 	my $total = $mset ? $mset->get_matches_estimated : undef;
 	ctx_prepare($q, $ctx);
 	my ($res, $html);
 	if ($err) {
 		$code = 400;
 		$html = '<pre>'.err_txt($ctx, $err).'</pre><hr>';
 	} elsif ($total == 0) {
 		if (defined($ctx->{-uxs_retried})) { # undo retry damage:
 			$q->{'q'} = $ctx->{-uxs_retried};
 		} elsif (index($q->{'q'}, '%') >= 0) { # retry unescaped
 			$ctx->{-uxs_retried} = $q->{'q'};
 			my $qs = $q->{'q'} = uri_unescape($q->{'q'});
 			$ctx->{srch}->query_approxidate($ctx->{ibx}->git, $qs);
 			return $ctx->{srch}->async_mset($qs, $opt,
 						\&sres_html_cb, $ctx, $opt, $q);
 		}
 		$code = 404;
 		$html = "<pre>\n[No results found]</pre><hr>";
 	} elsif ($q->{x} eq 'A') {
 		$res = adump($mset, $q, $ctx);
 	} else {
 		$ctx->{-html_tip} = search_nav_top($mset, $q, $ctx);
 		if ($q->{x} eq 't') {
 			$res = mset_thread($ctx, $mset, $q);
 		} else {
 			mset_summary($ctx, $mset, $q); # appends to {-html_tip}
 			$html = '';
 		}
 	}
 	$res //= html_oneshot($ctx, $code, $html);
 	my $wcb = delete $ctx->{wcb};
 	ref($res) eq 'CODE' ? $res->($wcb) : $wcb->($res);
 }

 # display non-nested search results similar to what users expect from
 # regular WWW search engines:
 sub mset_summary {
 	my ($ctx, $mset, $q) = @_;

 	my $total = $mset->get_matches_estimated;
 	my $pad = length("$total");
 	my $pfx = ' ' x $pad;
 	my $res = \($ctx->{-html_tip});
 	my $ibx = $ctx->{ibx};
 	my $obfs_ibx = $ibx->{obfuscate} ? $ibx : undef;
 	my @nums = @{$ibx->isrch->mset_to_artnums($mset)};
 	my %num2msg = map { $_->{num} => $_ } @{$ibx->over->get_all(@nums)};
 	my ($min, $max, %seen);

 	foreach my $m ($mset->items) {
 		my $num = shift @nums;
 		my $smsg = delete($num2msg{$num}) // do {
 			warn "$m $num expired\n";
 			next;
 		};
 		my $mid = $smsg->{mid};
 		next if $seen{$mid}++;
 		$mid = mid_href($mid);
 		$ctx->{-t_max} //= $smsg->{ts};
 		my $rank = sprintf("%${pad}d", $m->get_rank + 1);
 		my $pct = get_pct($m);

 		# only when sorting by relevance, ->items is always
 		# ordered descending:
 		$max //= $pct;
 		$min = $pct;

 		my $s = ascii_html($smsg->{subject});
 		my $f = ascii_html(delete $smsg->{from_name});
 		if ($obfs_ibx) {
 			obfuscate_addrs($obfs_ibx, $s);
 			obfuscate_addrs($obfs_ibx, $f);
 		}
 		my $date = fmt_ts($smsg->{ds});
 		$s = '(no subject)' if $s eq '';
 		$$res .= qq{$rank. <b><a\nhref="$mid/">}.
 			$s . "</a></b>\n";
 		$$res .= "$pfx  - by $f @ $date UTC [$pct%]\n\n";
 	}
 	if ($q->{r}) { # for descriptions in search_nav_bot
 		$q->{-min_pct} = $min;
 		$q->{-max_pct} = $max;
 	}
 	$$res .= search_nav_bot($ctx, $mset, $q);
 	undef;
 }

 # shorten "/full/path/to/Foo/Bar.pm" to "Foo/Bar.pm" so error
 # messages don't reveal FS layout info in case people use non-standard
 # installation paths
 sub path2inc ($) {
 	my $full = $_[0];
 	if (my $short = $rmap_inc{$full}) {
 		return $short;
 	} elsif (!scalar(keys %rmap_inc) && -e $full) {
 		# n.b. $INC{'PublicInbox::Gcf2'} is undef if libgit2-dev
 		# doesn't exist
 		my $f;
 		%rmap_inc = map {;
 			$f = $INC{$_};
 			defined $f ? ($f, $_) : ();
 		} keys %INC;
 		# fall back to basename as last resort
 		$rmap_inc{$full} // (split(m'/', $full))[-1];
 	} else {
 		$full;
 	}
 }

 sub err_txt {
 	my ($ctx, $err) = @_;
 	my $u = $ctx->{ibx}->base_url($ctx->{env}) . '_/text/help/';
 	$err =~ s/^\s*Exception:\s*//; # bad word to show users :P
 	$err =~ s!(\S+)!path2inc($1)!sge;
 	$err = ascii_html($err);
 	"\nBad query: <b>$err</b>\n" .
 		qq{See <a\nhref="$u">$u</a> for help on using search};
 }

 sub search_nav_top {
 	my ($mset, $q, $ctx) = @_;
 	my $m = $q->qs_html(x => 'm', r => undef, t => undef);
 	my $rv = qq{<form\nid=d\naction="?$m"\nmethod=post><pre>};
 	my $initial_q = $ctx->{-uxs_retried};
 	if (defined $initial_q) {
 		my $rewritten = $q->{'q'};
 		utf8::decode($initial_q);
 		utf8::decode($rewritten);
 		$initial_q = ascii_html($initial_q);
 		$rewritten = ascii_html($rewritten);
 		$rv .= " Warning: Initial query:\n <b>$initial_q</b>\n";
 		$rv .= " returned no results, used:\n";
 		$rv .= " <b>$rewritten</b>\n instead\n\n";
 	}

 	$rv .= 'Search results ordered by [';
 	if ($q->{r}) {
 		my $d = $q->qs_html(r => 0);
 		$rv .= qq{<a\nhref="?$d">date</a>|<b>relevance</b>};
 	} else {
 		my $d = $q->qs_html(r => 1);
 		$rv .= qq{<b>date</b>|<a\nhref="?$d">relevance</a>};
 	}

 	$rv .= ']  view[';

 	my $x = $q->{x};
 	my $pfx = "\t\t\t";
 	if ($x eq 't') {
 		my $s = $q->qs_html(x => '');
 		$rv .= qq{<a\nhref="?$s">summary</a>|<b>nested</b>};
 		$pfx = "thread overview <a\nhref=#t>below</a> | ";
 	} else {
 		my $t = $q->qs_html(x => 't');
 		$rv .= qq{<b>summary</b>|<a\nhref="?$t">nested</a>}
 	}
 	my $A = $q->qs_html(x => 'A', r => undef);
 	$rv .= qq{|<a\nhref="?$A">Atom feed</a>]\n};
 	$rv .= <<EOM if $x ne 't' && $q->{t};
 *** "t=1" collapses threads in summary, "full threads" requires mbox.gz ***
 EOM
 	$rv .= <<EOM if $x eq 'm';
 *** "x=m" ignored for GET requests, use download buttons below ***
 EOM
 	if ($ctx->{ibx}->isrch->has_threadid) {
 		$rv .= qq{${pfx}download mbox.gz: } .
 			# we set name=z w/o using it since it seems required for
 			# lynx (but works fine for w3m).
 			qq{<input\ntype=submit\nname=z\n} .
 				q{value="results only"/>} .
 			qq{|<input\ntype=submit\nname=x\n} .
 				q{value="full threads"/>};
 	} else { # BOFH needs to --reindex
 		$rv .= qq{${pfx}download: } .
 			qq{<input\ntype=submit\nname=z\nvalue="mbox.gz"/>}
 	}
 	$rv .= qq{</pre></form><pre>};
 }

 sub search_nav_bot { # also used by WwwListing for searching extindex miscidx
 	my ($ctx, $mset, $q) = @_;
 	my $total = $mset->get_matches_estimated;
 	my $l = $q->{l};
 	my $rv = '</pre><hr><pre id=t>';
 	my $o = $q->{o};
 	my $off = $o < 0 ? -($o + 1) : $o;
 	my $end = $off + $mset->size;
 	my $beg = $off + 1;

 	if ($beg <= $end) {
 		my $approx = $end == $total ? '' : '~';
 		$rv .= "Results $beg-$end of $approx$total";
 	} else {
 		$rv .= "No more results, only $total";
 	}
 	my ($next, $join, $prev, $nd, $pd);

 	if ($o >= 0) { # sort descending
 		my $n = $o + $l;
 		if ($n < $total) {
 			$next = $q->qs_html(o => $n, l => $l);
 			$nd = $q->{r} ? "[&lt;= $q->{-min_pct}%]" : '(older)';
 		}
 		if ($o > 0) {
 			$join = $n < $total ? ' | ' : "\t";
 			my $p = $o - $l;
 			$prev = $q->qs_html(o => ($p > 0 ? $p : 0));
 			$pd = $q->{r} ? "[&gt;= $q->{-max_pct}%]" : '(newer)';
 		}
 	} else { # o < 0, sort ascending
 		my $n = $o - $l;

 		if (-$n < $total) {
 			$next = $q->qs_html(o => $n, l => $l);
 			$nd = $q->{r} ? "[&lt;= $q->{-min_pct}%]" : '(newer)';
 		}
 		if ($o < -1) {
 			$join = -$n < $total ? ' | ' : "\t";
 			my $p = $o + $l;
 			$prev = $q->qs_html(o => ($p < 0 ? $p : 0));
 			$pd = $q->{r} ? "[&gt;= $q->{-max_pct}%]" : '(older)';
 		}
 	}

 	$rv .= qq{  <a\nhref="?$next"\nrel=next>next $nd</a>} if $next;
 	$rv .= $join if $join;
 	$rv .= qq{<a\nhref="?$prev"\nrel=prev>prev $pd</a>} if $prev;

 	my $rev = $q->qs_html(o => $o < 0 ? 0 : -1);
 	$rv .= qq{ | <a\nhref="?$rev">reverse</a>};
 	exists($ctx->{ibx}) and
 		$rv .= q{ | options <a href=#d>above</a></pre>};
 	$rv;
 }

 sub sort_relevance {
 	@{$_[0]} = sort {
 		(eval { $b->topmost->{pct} } // 0) <=>
 		(eval { $a->topmost->{pct} } // 0)
 	} @{$_[0]};
 }

 sub mset_thread {
 	my ($ctx, $mset, $q) = @_;
 	my $ibx = $ctx->{ibx};
 	my @pct = map { get_pct($_) } $mset->items;
 	my $msgs = $ibx->isrch->mset_to_smsg($ibx, $mset);
 	my $i = 0;
 	$_->{pct} = $pct[$i++] for @$msgs;
 	my $r = $q->{r};
 	if ($r) { # for descriptions in search_nav_bot
 		$q->{-min_pct} = min(@pct);
 		$q->{-max_pct} = max(@pct);
 	}
 	my $rootset = PublicInbox::SearchThread::thread($msgs,
 		$r ? \&sort_relevance : \&PublicInbox::View::sort_ds,
 		$ctx);
 	$ctx->{skel} = [ search_nav_bot($ctx, $mset, $q).'<pre>'. <<EOM ];
 -- pct% links below jump to the message on this page, permalinks otherwise --
 EOM
 	$ctx->{-upfx} = '';
 	$ctx->{anchor_idx} = 1;
 	$ctx->{cur_level} = 0;
 	$ctx->{mapping} = {};
 	$ctx->{searchview} = 1;
 	$ctx->{prev_attr} = '';
 	$ctx->{prev_level} = 0;
 	$ctx->{s_nr} = scalar(@$msgs).'+ results';

 	# reduce hash lookups in skel_dump
 	$ctx->{-obfs_ibx} = $ibx->{obfuscate} ? $ibx : undef;
 	PublicInbox::View::walk_thread($rootset, $ctx,
 		\&PublicInbox::View::pre_thread); # pushes to ctx->{skel}

 	# link $INBOX_DIR/description text to "recent" view around
 	# the newest message in this result set:
 	$ctx->{-t_max} = max(map { $_->{ts} } @$msgs);

 	@$msgs = reverse @$msgs if $r;
 	$ctx->{msgs} = $msgs;
 	PublicInbox::WwwStream::aresponse($ctx, \&mset_thread_i);
 }

 # callback for PublicInbox::WwwStream::getline
 sub mset_thread_i {
 	my ($ctx, $eml) = @_;
 	my $zfh = $ctx->zfh;
 	print $zfh $ctx->html_top if exists $ctx->{-html_tip};
 	$eml and return PublicInbox::View::emit_eml $ctx, $eml;
 	my $smsg = shift @{$ctx->{msgs}} or
 		print $zfh @{delete($ctx->{skel})};
 	$smsg;
 }

 sub ctx_prepare {
 	my ($q, $ctx) = @_;
 	my $qh = $q->{'q'};
 	utf8::decode($qh);
 	$qh = ascii_html($qh);
 	$ctx->{-q_value_html} = $qh;
 	$ctx->{-atom} = '?'.$q->qs_html(x => 'A', r => undef);
 	$ctx->{-title_html} = "$qh - search results";
 	my $extra = '';
 	$extra .= qq{<input\ntype=hidden\nname=r />} if $q->{r};
 	if (my $x = $q->{x}) {
 		$x = ascii_html($x);
 		$extra .= qq{<input\ntype=hidden\nname=x\nvalue="$x" />};
 	}
 	$ctx->{-extra_form_html} = $extra;
 }

 sub adump {
 	my ($mset, $q, $ctx) = @_;
 	$ctx->{ids} = $ctx->{ibx}->isrch->mset_to_artnums($mset);
 	$ctx->{search_query} = $q; # used by WwwAtomStream::atom_header
 	PublicInbox::WwwAtomStream->response($ctx, \&adump_i);
 }

 # callback for PublicInbox::WwwAtomStream::getline
 sub adump_i {
 	my ($ctx) = @_;
 	while (my $num = shift @{$ctx->{ids}}) {
 		my $smsg = eval { $ctx->{ibx}->over->get_art($num) } or next;
 		return $smsg;
 	}
 }

 1;
	# Copyright (C) all contributors <meta@public-inbox.org>
	# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
	#
	# Displays search results for the web interface
	package PublicInbox::SearchView;
	use strict;
	use v5.10.1;
	use List::Util qw(min max);
	use URI::Escape qw(uri_unescape);
	use PublicInbox::Smsg;
	use PublicInbox::Hval qw(ascii_html obfuscate_addrs mid_href fmt_ts);
	use PublicInbox::View;
	use PublicInbox::WwwAtomStream;
	use PublicInbox::WwwStream qw(html_oneshot);
	use PublicInbox::SearchThread;
	use PublicInbox::SearchQuery;
	use PublicInbox::Search qw(get_pct);
	my %rmap_inc;

	sub mbox_results {
	my ($ctx) = @_;
	my $q = PublicInbox::SearchQuery->new($ctx->{qp});
	if ($ctx->{env}->{'psgi.input'}->read(my $buf, 3)) {
	$q->{t} = 1 if $buf =~ /\Ax=[^0]/;
	}
	require PublicInbox::Mbox;
	$q->{x} eq 'm' ? PublicInbox::Mbox::mbox_all($ctx, $q) :
	sres_top_html($ctx);
	}

	sub sres_top_html {
	my ($ctx) = @_;
	my $srch = $ctx->{srch} = $ctx->{ibx}->isrch or
	return PublicInbox::WWW::need($ctx, 'Search');
	my $q = PublicInbox::SearchQuery->new($ctx->{qp});
	PublicInbox::View::addr2urlmap $ctx if $q->{x} eq 't';
	my $o = $q->{o} // 0;
	my $asc;
	if ($o < 0) {
	$asc = 1;
	$o = -($o + 1); # so [-1] is the last element, like Perl lists
	}

	# double the limit for expanded views:
	my $opt = {
	limit => $q->{l},
	offset => $o,
	relevance => $q->{r},
	threads => $q->{t},
	asc => $asc,
	};
	my $qs = $q->{'q'};
	$srch->query_approxidate($ctx->{ibx}->git, $qs);
	sub {
	$ctx->{wcb} = $_[0]; # PSGI server supplied write cb
	$srch->async_mset($qs, $opt, \&sres_html_cb, $ctx, $opt, $q);
	}
	}

	sub sres_html_cb { # async_mset cb
	my ($ctx, $opt, $q, $mset, $err) = @_;
	my $code = 200;
	my $total = $mset ? $mset->get_matches_estimated : undef;
	ctx_prepare($q, $ctx);
	my ($res, $html);
	if ($err) {
	$code = 400;
	$html = '<pre>'.err_txt($ctx, $err).'</pre><hr>';
	} elsif ($total == 0) {
	if (defined($ctx->{-uxs_retried})) { # undo retry damage:
	$q->{'q'} = $ctx->{-uxs_retried};
	} elsif (index($q->{'q'}, '%') >= 0) { # retry unescaped
	$ctx->{-uxs_retried} = $q->{'q'};
	my $qs = $q->{'q'} = uri_unescape($q->{'q'});
	$ctx->{srch}->query_approxidate($ctx->{ibx}->git, $qs);
	return $ctx->{srch}->async_mset($qs, $opt,
	\&sres_html_cb, $ctx, $opt, $q);
	}
	$code = 404;
	$html = "<pre>\n[No results found]</pre><hr>";
	} elsif ($q->{x} eq 'A') {
	$res = adump($mset, $q, $ctx);
	} else {
	$ctx->{-html_tip} = search_nav_top($mset, $q, $ctx);
	if ($q->{x} eq 't') {
	$res = mset_thread($ctx, $mset, $q);
	} else {
	mset_summary($ctx, $mset, $q); # appends to {-html_tip}
	$html = '';
	}
	}
	$res //= html_oneshot($ctx, $code, $html);
	my $wcb = delete $ctx->{wcb};
	ref($res) eq 'CODE' ? $res->($wcb) : $wcb->($res);
	}

	# display non-nested search results similar to what users expect from
	# regular WWW search engines:
	sub mset_summary {
	my ($ctx, $mset, $q) = @_;

	my $total = $mset->get_matches_estimated;
	my $pad = length("$total");
	my $pfx = ' ' x $pad;
	my $res = \($ctx->{-html_tip});
	my $ibx = $ctx->{ibx};
	my $obfs_ibx = $ibx->{obfuscate} ? $ibx : undef;
	my @nums = @{$ibx->isrch->mset_to_artnums($mset)};
	my %num2msg = map { $_->{num} => $_ } @{$ibx->over->get_all(@nums)};
	my ($min, $max, %seen);

	foreach my $m ($mset->items) {
	my $num = shift @nums;
	my $smsg = delete($num2msg{$num}) // do {
	warn "$m $num expired\n";
	next;
	};
	my $mid = $smsg->{mid};
	next if $seen{$mid}++;
	$mid = mid_href($mid);
	$ctx->{-t_max} //= $smsg->{ts};
	my $rank = sprintf("%${pad}d", $m->get_rank + 1);
	my $pct = get_pct($m);

	# only when sorting by relevance, ->items is always
	# ordered descending:
	$max //= $pct;
	$min = $pct;

	my $s = ascii_html($smsg->{subject});
	my $f = ascii_html(delete $smsg->{from_name});
	if ($obfs_ibx) {
	obfuscate_addrs($obfs_ibx, $s);
	obfuscate_addrs($obfs_ibx, $f);
	}
	my $date = fmt_ts($smsg->{ds});
	$s = '(no subject)' if $s eq '';
	$$res .= qq{$rank. <b><a\nhref="$mid/">}.
	$s . "</a></b>\n";
	$$res .= "$pfx - by $f @ $date UTC [$pct%]\n\n";
	}
	if ($q->{r}) { # for descriptions in search_nav_bot
	$q->{-min_pct} = $min;
	$q->{-max_pct} = $max;
	}
	$$res .= search_nav_bot($ctx, $mset, $q);
	undef;
	}

	# shorten "/full/path/to/Foo/Bar.pm" to "Foo/Bar.pm" so error
	# messages don't reveal FS layout info in case people use non-standard
	# installation paths
	sub path2inc ($) {
	my $full = $_[0];
	if (my $short = $rmap_inc{$full}) {
	return $short;
	} elsif (!scalar(keys %rmap_inc) && -e $full) {
	# n.b. $INC{'PublicInbox::Gcf2'} is undef if libgit2-dev
	# doesn't exist
	my $f;
	%rmap_inc = map {;
	$f = $INC{$_};
	defined $f ? ($f, $_) : ();
	} keys %INC;
	# fall back to basename as last resort
	$rmap_inc{$full} // (split(m'/', $full))[-1];
	} else {
	$full;
	}
	}

	sub err_txt {
	my ($ctx, $err) = @_;
	my $u = $ctx->{ibx}->base_url($ctx->{env}) . '_/text/help/';
	$err =~ s/^\sException:\s//; # bad word to show users :P
	$err =~ s!(\S+)!path2inc($1)!sge;
	$err = ascii_html($err);
	"\nBad query: <b>$err</b>\n" .
	qq{See <a\nhref="$u">$u</a> for help on using search};
	}

	sub search_nav_top {
	my ($mset, $q, $ctx) = @_;
	my $m = $q->qs_html(x => 'm', r => undef, t => undef);
	my $rv = qq{<form\nid=d\naction="?$m"\nmethod=post><pre>};
	my $initial_q = $ctx->{-uxs_retried};
	if (defined $initial_q) {
	my $rewritten = $q->{'q'};
	utf8::decode($initial_q);
	utf8::decode($rewritten);
	$initial_q = ascii_html($initial_q);
	$rewritten = ascii_html($rewritten);
	$rv .= " Warning: Initial query:\n <b>$initial_q</b>\n";
	$rv .= " returned no results, used:\n";
	$rv .= " <b>$rewritten</b>\n instead\n\n";
	}

	$rv .= 'Search results ordered by [';
	if ($q->{r}) {
	my $d = $q->qs_html(r => 0);
	$rv .= qq{<a\nhref="?$d">date</a>\|<b>relevance</b>};
	} else {
	my $d = $q->qs_html(r => 1);
	$rv .= qq{<b>date</b>\|<a\nhref="?$d">relevance</a>};
	}

	$rv .= '] view[';

	my $x = $q->{x};
	my $pfx = "\t\t\t";
	if ($x eq 't') {
	my $s = $q->qs_html(x => '');
	$rv .= qq{<a\nhref="?$s">summary</a>\|<b>nested</b>};
	$pfx = "thread overview <a\nhref=#t>below</a> \| ";
	} else {
	my $t = $q->qs_html(x => 't');
	$rv .= qq{<b>summary</b>\|<a\nhref="?$t">nested</a>}
	}
	my $A = $q->qs_html(x => 'A', r => undef);
	$rv .= qq{\|<a\nhref="?$A">Atom feed</a>]\n};
	$rv .= <<EOM if $x ne 't' && $q->{t};
	* "t=1" collapses threads in summary, "full threads" requires mbox.gz *
	EOM
	$rv .= <<EOM if $x eq 'm';
	* "x=m" ignored for GET requests, use download buttons below *
	EOM
	if ($ctx->{ibx}->isrch->has_threadid) {
	$rv .= qq{${pfx}download mbox.gz: } .
	# we set name=z w/o using it since it seems required for
	# lynx (but works fine for w3m).
	qq{<input\ntype=submit\nname=z\n} .
	q{value="results only"/>} .
	qq{\|<input\ntype=submit\nname=x\n} .
	q{value="full threads"/>};
	} else { # BOFH needs to --reindex
	$rv .= qq{${pfx}download: } .
	qq{<input\ntype=submit\nname=z\nvalue="mbox.gz"/>}
	}
	$rv .= qq{</pre></form><pre>};
	}

	sub search_nav_bot { # also used by WwwListing for searching extindex miscidx
	my ($ctx, $mset, $q) = @_;
	my $total = $mset->get_matches_estimated;
	my $l = $q->{l};
	my $rv = '</pre><hr><pre id=t>';
	my $o = $q->{o};
	my $off = $o < 0 ? -($o + 1) : $o;
	my $end = $off + $mset->size;
	my $beg = $off + 1;

	if ($beg <= $end) {
	my $approx = $end == $total ? '' : '~';
	$rv .= "Results $beg-$end of $approx$total";
	} else {
	$rv .= "No more results, only $total";
	}
	my ($next, $join, $prev, $nd, $pd);

	if ($o >= 0) { # sort descending
	my $n = $o + $l;
	if ($n < $total) {
	$next = $q->qs_html(o => $n, l => $l);
	$nd = $q->{r} ? "[<= $q->{-min_pct}%]" : '(older)';
	}
	if ($o > 0) {
	$join = $n < $total ? ' \| ' : "\t";
	my $p = $o - $l;
	$prev = $q->qs_html(o => ($p > 0 ? $p : 0));
	$pd = $q->{r} ? "[>= $q->{-max_pct}%]" : '(newer)';
	}
	} else { # o < 0, sort ascending
	my $n = $o - $l;

	if (-$n < $total) {
	$next = $q->qs_html(o => $n, l => $l);
	$nd = $q->{r} ? "[<= $q->{-min_pct}%]" : '(newer)';
	}
	if ($o < -1) {
	$join = -$n < $total ? ' \| ' : "\t";
	my $p = $o + $l;
	$prev = $q->qs_html(o => ($p < 0 ? $p : 0));
	$pd = $q->{r} ? "[>= $q->{-max_pct}%]" : '(older)';
	}
	}

	$rv .= qq{ <a\nhref="?$next"\nrel=next>next $nd</a>} if $next;
	$rv .= $join if $join;
	$rv .= qq{<a\nhref="?$prev"\nrel=prev>prev $pd</a>} if $prev;

	my $rev = $q->qs_html(o => $o < 0 ? 0 : -1);
	$rv .= qq{ \| <a\nhref="?$rev">reverse</a>};
	exists($ctx->{ibx}) and
	$rv .= q{ \| options <a href=#d>above</a></pre>};
	$rv;
	}

	sub sort_relevance {
	@{$_[0]} = sort {
	(eval { $b->topmost->{pct} } // 0) <=>
	(eval { $a->topmost->{pct} } // 0)
	} @{$_[0]};
	}

	sub mset_thread {
	my ($ctx, $mset, $q) = @_;
	my $ibx = $ctx->{ibx};
	my @pct = map { get_pct($_) } $mset->items;
	my $msgs = $ibx->isrch->mset_to_smsg($ibx, $mset);
	my $i = 0;
	$_->{pct} = $pct[$i++] for @$msgs;
	my $r = $q->{r};
	if ($r) { # for descriptions in search_nav_bot
	$q->{-min_pct} = min(@pct);
	$q->{-max_pct} = max(@pct);
	}
	my $rootset = PublicInbox::SearchThread::thread($msgs,
	$r ? \&sort_relevance : \&PublicInbox::View::sort_ds,
	$ctx);
	$ctx->{skel} = [ search_nav_bot($ctx, $mset, $q).'<pre>'. <<EOM ];
	-- pct% links below jump to the message on this page, permalinks otherwise --
	EOM
	$ctx->{-upfx} = '';
	$ctx->{anchor_idx} = 1;
	$ctx->{cur_level} = 0;
	$ctx->{mapping} = {};
	$ctx->{searchview} = 1;
	$ctx->{prev_attr} = '';
	$ctx->{prev_level} = 0;
	$ctx->{s_nr} = scalar(@$msgs).'+ results';

	# reduce hash lookups in skel_dump
	$ctx->{-obfs_ibx} = $ibx->{obfuscate} ? $ibx : undef;
	PublicInbox::View::walk_thread($rootset, $ctx,
	\&PublicInbox::View::pre_thread); # pushes to ctx->{skel}

	# link $INBOX_DIR/description text to "recent" view around
	# the newest message in this result set:
	$ctx->{-t_max} = max(map { $_->{ts} } @$msgs);

	@$msgs = reverse @$msgs if $r;
	$ctx->{msgs} = $msgs;
	PublicInbox::WwwStream::aresponse($ctx, \&mset_thread_i);
	}

	# callback for PublicInbox::WwwStream::getline
	sub mset_thread_i {
	my ($ctx, $eml) = @_;
	my $zfh = $ctx->zfh;
	print $zfh $ctx->html_top if exists $ctx->{-html_tip};
	$eml and return PublicInbox::View::emit_eml $ctx, $eml;
	my $smsg = shift @{$ctx->{msgs}} or
	print $zfh @{delete($ctx->{skel})};
	$smsg;
	}

	sub ctx_prepare {
	my ($q, $ctx) = @_;
	my $qh = $q->{'q'};
	utf8::decode($qh);
	$qh = ascii_html($qh);
	$ctx->{-q_value_html} = $qh;
	$ctx->{-atom} = '?'.$q->qs_html(x => 'A', r => undef);
	$ctx->{-title_html} = "$qh - search results";
	my $extra = '';
	$extra .= qq{<input\ntype=hidden\nname=r />} if $q->{r};
	if (my $x = $q->{x}) {
	$x = ascii_html($x);
	$extra .= qq{<input\ntype=hidden\nname=x\nvalue="$x" />};
	}
	$ctx->{-extra_form_html} = $extra;
	}

	sub adump {
	my ($mset, $q, $ctx) = @_;
	$ctx->{ids} = $ctx->{ibx}->isrch->mset_to_artnums($mset);
	$ctx->{search_query} = $q; # used by WwwAtomStream::atom_header
	PublicInbox::WwwAtomStream->response($ctx, \&adump_i);
	}

	# callback for PublicInbox::WwwAtomStream::getline
	sub adump_i {
	my ($ctx) = @_;
	while (my $num = shift @{$ctx->{ids}}) {
	my $smsg = eval { $ctx->{ibx}->over->get_art($num) } or next;
	return $smsg;
	}
	}

	1;