X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FView.pm;h=9f1bf46005ad66c3332ae4e875b5e71cd96254da;hb=172416d1cd465da4242cc744a3f309d307f1311d;hp=9393d44334ab12d41ad24309d188587dfd41985c;hpb=d4560fca4d1dddafd21a78c793679a1b19cd4db4;p=public-inbox.git

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 9393d443..9f1bf460 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -8,11 +8,9 @@ use strict;
 use warnings;
 use URI::Escape qw/uri_escape_utf8/;
 use Date::Parse qw/str2time/;
-use Encode::MIME::Header;
-use Plack::Util;
 use PublicInbox::Hval qw/ascii_html/;
 use PublicInbox::Linkify;
-use PublicInbox::MID qw/mid_clean id_compress mid_mime/;
+use PublicInbox::MID qw/mid_clean id_compress mid_mime mid_escape/;
 use PublicInbox::MsgIter;
 use PublicInbox::Address;
 use PublicInbox::WwwStream;
@@ -24,14 +22,13 @@ sub th_pfx ($) { $_[0] == 0 ? '' : TCHILD };
 
 # public functions: (unstable)
 sub msg_html {
-	my ($ctx, $mime, $footer) = @_;
+	my ($ctx, $mime) = @_;
 	my $hdr = $mime->header_obj;
 	my $tip = _msg_html_prepare($hdr, $ctx);
-	PublicInbox::WwwStream->new($ctx, sub {
+	PublicInbox::WwwStream->response($ctx, 200, sub {
 		my ($nr, undef) = @_;
 		if ($nr == 1) {
-			$tip . multipart_text_as_html($mime, '') .
-				'</pre><hr />'
+			$tip . multipart_text_as_html($mime, '') . '</pre><hr>'
 		} elsif ($nr == 2) {
 			# fake an EOF if generating the footer fails;
 			# we want to at least show the message if something
@@ -49,32 +46,55 @@ sub msg_html {
 # /$INBOX/$MESSAGE_ID/#R
 sub msg_reply {
 	my ($ctx, $hdr) = @_;
-	my $se_url = 'https://git-htmldocs.bogomips.org/git-send-email.html';
+	my $se_url =
+	 'https://kernel.org/pub/software/scm/git/docs/git-send-email.html';
+	my $p_url =
+	 'https://en.wikipedia.org/wiki/Posting_style#Interleaved_style';
+
+	my $info = '';
+	if (my $url = $ctx->{-inbox}->{infourl}) {
+		$url = PublicInbox::Hval::prurl($ctx->{env}, $url);
+		$info = qq(\n  List information: <a\nhref="$url">$url</a>\n);
+	}
 
 	my ($arg, $link) = mailto_arg_link($hdr);
 	push @$arg, '/path/to/YOUR_REPLY';
-
-	"<pre\nid=R>".
-	"You may reply publically to <a\nhref=#t>this message</a> via\n".
-	"plain-text email using any one of the following methods:\n\n" .
-	"* Save the following mbox file, import it into your mail client,\n" .
-	"  and reply-to-all from there: <a\nhref=raw>mbox</a>\n\n" .
-	"* Reply to all the recipients using the <b>--to</b>, <b>--cc</b>,\n" .
-	"  and <b>--in-reply-to</b> switches of git-send-email(1):\n\n" .
-	"  git send-email \\\n    " .
-	join(" \\\n    ", @$arg ). "\n\n" .
-	qq(  <a\nhref="$se_url">$se_url</a>\n\n) .
-	"* If your mail client supports setting the <b>In-Reply-To</b>" .
-	" header\n  via mailto: links, try the " .
-	qq(<a\nhref="$link">mailto: link</a>\n) .
-	'</pre>';
+	$arg = ascii_html(join(" \\\n    ", '', @$arg));
+	<<EOF
+<hr><pre
+id=R><b>Reply instructions:</b>
+
+You may reply publically to <a
+href=#t>this message</a> via plain-text email
+using any one of the following methods:
+
+* Save the following mbox file, import it into your mail client,
+  and reply-to-all from there: <a
+href=raw>mbox</a>
+
+  Avoid top-posting and favor interleaved quoting:
+  <a
+href="$p_url">$p_url</a>
+$info
+* Reply to all the recipients using the <b>--to</b>, <b>--cc</b>,
+  and <b>--in-reply-to</b> switches of git-send-email(1):
+
+  git send-email$arg
+
+  <a
+href="$se_url">$se_url</a>
+
+* If your mail client supports setting the <b>In-Reply-To</b> header
+  via mailto: links, try the <a
+href="$link">mailto: link</a></pre>
+EOF
 }
 
 sub in_reply_to {
 	my ($hdr) = @_;
 	my $irt = $hdr->header_raw('In-Reply-To');
 
-	return mid_clean($irt) if (defined $irt);
+	return mid_clean($irt) if defined $irt && $irt ne '';
 
 	my $refs = $hdr->header_raw('References');
 	if ($refs && $refs =~ /<([^>]+)>\s*\z/s) {
@@ -103,47 +123,77 @@ sub index_entry {
 	my $subj = $hdr->header('Subject');
 
 	my $mid_raw = mid_clean(mid_mime($mime));
-	my $id = id_compress($mid_raw);
+	my $id = id_compress($mid_raw, 1);
 	my $id_m = 'm'.$id;
-	my $mid = PublicInbox::Hval->new_msgid($mid_raw);
 
 	my $root_anchor = $ctx->{root_anchor} || '';
 	my $irt = in_reply_to($hdr);
 
-	my $rv = '<b>'.ascii_html($subj).'</b>';
-	$rv = "<u\nid=u>$rv</u>" if $root_anchor eq $id_m;
-	$rv .= "\n";
+	my $rv = "<a\nhref=#e$id\nid=m$id>*</a> ";
+	$subj = '<b>'.ascii_html($subj).'</b>';
+	$subj = "<u\nid=u>$subj</u>" if $root_anchor eq $id_m;
+	$rv .= $subj . "\n";
 	$rv .= _th_index_lite($mid_raw, $irt, $id, $ctx);
 	my @tocc;
 	foreach my $f (qw(To Cc)) {
 		my $dst = _hdr_names($hdr, $f);
 		push @tocc, "$f: $dst" if $dst ne '';
 	}
-	my $mapping = $ctx->{mapping};
 	$rv .= "From: "._hdr_names($hdr, 'From').' @ '._msg_date($hdr)." UTC";
 	my $upfx = $ctx->{-upfx};
-	$rv .= qq{ (<a\nhref="$upfx$mid_raw/">permalink</a> / };
-	$rv .= qq{<a\nhref="$upfx$mid_raw/raw">raw</a>)\n};
+	my $mhref = $upfx . mid_escape($mid_raw) . '/';
+	$rv .= qq{ (<a\nhref="$mhref">permalink</a> / };
+	$rv .= qq{<a\nhref="${mhref}raw">raw</a>)\n};
 	$rv .= '  '.join('; +', @tocc) . "\n" if @tocc;
+
+	my $mapping = $ctx->{mapping};
 	if (!$mapping && $irt) {
-		$rv .= qq(In-Reply-To: &lt;<a\nhref="$upfx$irt/">$irt</a>&gt;\n)
+		my $mirt = PublicInbox::Hval->new_msgid($irt);
+		my $href = $upfx . $mirt->{href}. '/';
+		my $html = $mirt->as_html;
+		$rv .= qq(In-Reply-To: &lt;<a\nhref="$href">$html</a>&gt;\n)
 	}
 	$rv .= "\n";
 
 	# scan through all parts, looking for displayable text
-	my $href = $mid->as_href;
-	my $mhref = $ctx->{-upfx}.$href.'/';
 	msg_iter($mime, sub { $rv .= add_text_body($mhref, $_[0]) });
 
 	# add the footer
 	$rv .= "\n<a\nhref=#$id_m\nid=e$id>^</a> ".
 		"<a\nhref=\"$mhref\">permalink</a>" .
-		" / <a\nhref=\"${mhref}raw\">raw</a>" .
-		" / <a\nhref=\"${mhref}#R\">reply</a>";
+		" <a\nhref=\"${mhref}raw\">raw</a>" .
+		" <a\nhref=\"${mhref}#R\">reply</a>";
+
+	my $hr;
 	if (my $pct = $ctx->{pct}) { # used by SearchView.pm
-		$rv .= " [relevance $pct->{$mid_raw}%]";
+		$rv .= "\t[relevance $pct->{$mid_raw}%]";
+		$hr = 1;
+	} elsif ($mapping) {
+		my $threaded = 'threaded';
+		my $flat = 'flat';
+		my $end = '';
+		if ($ctx->{flat}) {
+			$hr = 1;
+			$flat = "<b>$flat</b>";
+		} else {
+			$threaded = "<b>$threaded</b>";
+		}
+		$rv .= "\t[<a\nhref=\"${mhref}T/#u\">$flat</a>";
+		$rv .= "|<a\nhref=\"${mhref}t/#u\">$threaded</a>]";
+		$rv .= " <a\nhref=#r$id>$ctx->{s_nr}</a>";
+	} else {
+		$hr = $ctx->{-hr};
 	}
-	$rv .= $more ? "\n\n" : "\n";
+
+	$rv .= $more ? '</pre><hr><pre>' : '</pre>' if $hr;
+	$rv;
+}
+
+sub pad_link ($$;$) {
+	my ($mid, $level, $s) = @_;
+	$s ||= '...';
+	my $id = id_compress($mid, 1);
+	(' 'x19).indent_for($level).th_pfx($level)."<a\nhref=#r$id>($s)</a>\n";
 }
 
 sub _th_index_lite {
@@ -155,32 +205,56 @@ sub _th_index_lite {
 	my $map = $mapping->{$mid_raw};
 	my $nr_c = scalar @{$map->[0]};
 	my $nr_s = 0;
-	if (defined $irt) {
-		my $irt_map = $mapping->{$irt};
+	my $level = $map->[4];
+	my $idx = $map->[3];
+	my $irt_map = $mapping->{$irt} if defined $irt;
+	if (defined $irt_map) {
 		my $siblings = $irt_map->[0];
 		$nr_s = scalar(@$siblings) - 1;
-		$nr_s = 0 if $nr_s < 0;
 		$rv .= $pad . $irt_map->[1];
-		my $idx = $map->[3];
 		if ($idx > 0) {
 			my $prev = $siblings->[$idx - 1];
-			$rv .= $pad . $mapping->{$prev->messageid}->[1];
+			my $pmid = $prev->messageid;
+			if ($idx > 2) {
+				my $s = ($idx - 1). ' preceding siblings ...';
+				$rv .= pad_link($pmid, $level, $s);
+			} elsif ($idx == 2) {
+				my $ppmid = $siblings->[0]->messageid;
+				$rv .= $pad . $mapping->{$ppmid}->[1];
+			}
+			$rv .= $pad . $mapping->{$pmid}->[1];
 		}
 	}
 	my $s_s = nr_to_s($nr_s, 'sibling', 'siblings');
 	my $s_c = nr_to_s($nr_c, 'reply', 'replies');
 	my $this = $map->[1];
 	$this =~ s!\n\z!</b>\n!s;
-	$this =~ s!<a\nhref.*a> !!s; # no point in duplicating subject
+	$this =~ s!<a\nhref.*</a> !!s; # no point in duplicating subject
+	$this =~ s!<a\nhref=[^>]+>([^<]+)</a>!$1!s; # no point linking to self
 	$rv .= "<b>@ $this";
 	my $node = $map->[2];
 	if (my $child = $node->child) {
-		$rv .= $pad . $mapping->{$child->messageid}->[1];
+		my $cmid = $child->messageid;
+		$rv .= $pad . $mapping->{$cmid}->[1];
+		if ($nr_c > 2) {
+			my $s = ($nr_c - 1). ' more replies';
+			$rv .= pad_link($cmid, $level + 1, $s);
+		} elsif (my $cn = $child->next) {
+			$rv .= $pad . $mapping->{$cn->messageid}->[1];
+		}
 	}
 	if (my $next = $node->next) {
-		$rv .= $pad .  $mapping->{$next->messageid}->[1];
+		my $nmid = $next->messageid;
+		$rv .= $pad . $mapping->{$nmid}->[1];
+		my $nnext = $nr_s - $idx;
+		if ($nnext > 2) {
+			my $s = ($nnext - 1).' subsequent siblings';
+			$rv .= pad_link($nmid, $level, $s);
+		} elsif (my $nn = $next->next) {
+			$rv .= $pad . $mapping->{$nn->messageid}->[1];
+		}
 	}
-	$rv .= "<a\nhref=#e$id\nid=m$id>_<a> <a\nhref=#r$id\n>$s_s, $s_c</a>\n";
+	$rv .= $pad ."<a\nhref=#r$id>$s_s, $s_c; $ctx->{s_nr}</a>\n";
 }
 
 sub walk_thread {
@@ -203,10 +277,54 @@ sub pre_thread  {
 		$idx = scalar @$m;
 		push @$m, $node;
 	}
-	$mapping->{$node->messageid} = [ [], '', $node, $idx ];
+	$mapping->{$node->messageid} = [ [], '', $node, $idx, $level ];
 	skel_dump($ctx, $level, $node);
 }
 
+sub thread_index_entry {
+	my ($ctx, $level, $mime) = @_;
+	my ($beg, $end) = thread_adj_level($ctx, $level);
+	$beg . '<pre>' . index_entry($mime, $ctx, 0) . '</pre>' . $end;
+}
+
+sub stream_thread ($$) {
+	my ($th, $ctx) = @_;
+	my $inbox = $ctx->{-inbox};
+	my $mime;
+	my @q = map { (0, $_) } $th->rootset;
+	my $level;
+	while (@q) {
+		$level = shift @q;
+		my $node = shift @q or next;
+		unshift @q, $level+1, $node->child, $level, $node->next;
+		$mime = $inbox->msg_by_mid($node->messageid) and last;
+	}
+	return missing_thread($ctx) unless $mime;
+
+	$mime = Email::MIME->new($mime);
+	$ctx->{-title_html} = ascii_html($mime->header('Subject'));
+	$ctx->{-html_tip} = thread_index_entry($ctx, $level, $mime);
+	PublicInbox::WwwStream->response($ctx, 200, sub {
+		return unless $ctx;
+		while (@q) {
+			$level = shift @q;
+			my $node = shift @q or next;
+			unshift @q, $level+1, $node->child, $level, $node->next;
+			my $mid = $node->messageid;
+			if ($mime = $inbox->msg_by_mid($mid)) {
+				$mime = Email::MIME->new($mime);
+				return thread_index_entry($ctx, $level, $mime);
+			} else {
+				return ghost_index_entry($ctx, $level, $mid);
+			}
+		}
+		my $ret = join('', thread_adj_level($ctx, 0));
+		$ret .= ${$ctx->{dst}}; # skel
+		$ctx = undef;
+		$ret;
+	});
+}
+
 sub thread_html {
 	my ($ctx) = @_;
 	my $mid = $ctx->{mid};
@@ -214,34 +332,41 @@ sub thread_html {
 	my $msgs = load_results($sres);
 	my $nr = $sres->{total};
 	return missing_thread($ctx) if $nr == 0;
-	my $skel = '</pre><hr /><pre>';
+	my $skel = '<hr><pre>';
 	$skel .= $nr == 1 ? 'only message in thread' : 'end of thread';
-	$skel .= ", back to <a\nhref=\"../../\">index</a>";
-	$skel .= "\n<a\nid=t>$nr+ messages in thread:</a> (download: ";
-	$skel .= "<a\nhref=\"../t.mbox.gz\">mbox.gz</a>";
+	$skel .= ", back to <a\nhref=\"../../\">index</a>\n\n";
+	$skel .= "<b\nid=t>Thread overview:</b> ";
+	$skel .= $nr == 1 ? '(only message)' : "$nr+ messages";
+	$skel .= " (download: <a\nhref=\"../t.mbox.gz\">mbox.gz</a>";
 	$skel .= " / follow: <a\nhref=\"../t.atom\">Atom feed</a>)\n";
+	$skel .= "-- links below jump to the message on this page --\n";
+	$ctx->{-upfx} = '../../';
 	$ctx->{cur_level} = 0;
 	$ctx->{dst} = \$skel;
-	$ctx->{mapping} = {}; # mid -> [ reply count, from@date, node ];
 	$ctx->{prev_attr} = '';
 	$ctx->{prev_level} = 0;
 	$ctx->{root_anchor} = anchor_for($mid);
 	$ctx->{seen} = {};
+	$ctx->{mapping} = {};
+	$ctx->{s_nr} = "$nr+ messages in thread";
 
-	walk_thread(thread_results($msgs), $ctx, *pre_thread);
+	my $th = thread_results($msgs);
+	walk_thread($th, $ctx, *pre_thread);
+	$skel .= '</pre>';
+	return stream_thread($th, $ctx) unless $ctx->{flat};
 
-	# lazy load the full message from mini_mime:
+	# flat display: lazy load the full message from mini_mime:
 	my $inbox = $ctx->{-inbox};
 	my $mime;
 	while ($mime = shift @$msgs) {
 		$mime = $inbox->msg_by_mid(mid_clean(mid_mime($mime))) and last;
 	}
+	return missing_thread($ctx) unless $mime;
 	$mime = Email::MIME->new($mime);
-	$ctx->{-upfx} = '../../';
 	$ctx->{-title_html} = ascii_html($mime->header('Subject'));
 	$ctx->{-html_tip} = '<pre>'.index_entry($mime, $ctx, scalar @$msgs);
 	$mime = undef;
-	my $body = PublicInbox::WwwStream->new($ctx, sub {
+	PublicInbox::WwwStream->response($ctx, 200, sub {
 		return unless $msgs;
 		while ($mime = shift @$msgs) {
 			$mid = mid_clean(mid_mime($mime));
@@ -252,9 +377,8 @@ sub thread_html {
 			return index_entry($mime, $ctx, scalar @$msgs);
 		}
 		$msgs = undef;
-		$skel .= '</pre>';
+		$skel;
 	});
-	[ 200, ['Content-Type', 'text/html; charset=UTF-8'], $body ];
 }
 
 sub multipart_text_as_html {
@@ -283,14 +407,16 @@ sub flush_quote {
 	$$s .= qq(<span\nclass="q">) . $rv . '</span>'
 }
 
-sub attach_link ($$$$) {
-	my ($upfx, $ct, $p, $fn) = @_;
+sub attach_link ($$$$;$) {
+	my ($upfx, $ct, $p, $fn, $err) = @_;
 	my ($part, $depth, @idx) = @$p;
 	my $nl = $idx[-1] > 1 ? "\n" : '';
 	my $idx = join('.', @idx);
 	my $size = bytes::length($part->body);
-	$ct ||= 'text/plain';
-	$ct =~ s/;.*//; # no attributes
+
+	# hide attributes normally, unless we want to aid users in
+	# spotting MUA problems:
+	$ct =~ s/;.*// unless $err;
 	$ct = ascii_html($ct);
 	my $desc = $part->header('Content-Description');
 	$desc = $fn unless defined $desc;
@@ -303,31 +429,50 @@ sub attach_link ($$$$) {
 	} else {
 		$sfn = 'a.bin';
 	}
-	my @ret = qq($nl<a\nhref="$upfx$idx-$sfn">[-- Attachment #$idx: );
+	my $ret = qq($nl<a\nhref="$upfx$idx-$sfn">);
+	if ($err) {
+		$ret .=
+"[-- Warning: decoded text below may be mangled --]\n";
+	}
+	$ret .= "[-- Attachment #$idx: ";
 	my $ts = "Type: $ct, Size: $size bytes";
-	push(@ret, ($desc eq '') ? "$ts --]" : "$desc --]\n[-- $ts --]");
-	join('', @ret, "</a>\n");
+	$ret .= ($desc eq '') ? "$ts --]" : "$desc --]\n[-- $ts --]";
+	$ret .= "</a>\n";
 }
 
 sub add_text_body {
 	my ($upfx, $p) = @_; # from msg_iter: [ Email::MIME, depth, @idx ]
 	my ($part, $depth, @idx) = @$p;
-	my $ct = $part->content_type;
+	my $ct = $part->content_type || 'text/plain';
 	my $fn = $part->filename;
 
-	if (defined $ct && $ct =~ m!\btext/x?html\b!i) {
+	if ($ct =~ m!\btext/x?html\b!i) {
 		return attach_link($upfx, $ct, $p, $fn);
 	}
 
 	my $s = eval { $part->body_str };
 
 	# badly-encoded message? tell the world about it!
-	return attach_link($upfx, $ct, $p, $fn) if $@;
+	my $err = $@;
+	if ($err) {
+		if ($ct =~ m!\btext/plain\b!i) {
+			# Try to assume UTF-8 because Alpine seems to
+			# do wacky things and set charset=X-UNKNOWN
+			$part->charset_set('UTF-8');
+			$s = eval { $part->body_str };
+
+			# If forcing charset=UTF-8 failed,
+			# attach_link will warn further down...
+			$s = $part->body if $@;
+		} else {
+			return attach_link($upfx, $ct, $p, $fn);
+		}
+	}
 
 	my @lines = split(/^/m, $s);
 	$s = '';
-	if (defined($fn) || $depth > 0) {
-		$s .= attach_link($upfx, $ct, $p, $fn);
+	if (defined($fn) || $depth > 0 || $err) {
+		$s .= attach_link($upfx, $ct, $p, $fn, $err);
 		$s .= "\n";
 	}
 	my @quot;
@@ -367,7 +512,7 @@ sub _msg_html_prepare {
 		$ctx->{-upfx} = '../';
 	}
 	my @title;
-	my $mid = $hdr->header_raw('Message-ID');
+	my $mid = mid_clean($hdr->header_raw('Message-ID'));
 	$mid = PublicInbox::Hval->new_msgid($mid);
 	foreach my $h (qw(From To Cc Subject Date)) {
 		my $v = $hdr->header($h);
@@ -404,11 +549,12 @@ sub thread_skel {
 	my $mid = mid_clean($hdr->header_raw('Message-ID'));
 	my $sres = $srch->get_thread($mid);
 	my $nr = $sres->{total};
-	my $expand = qq(<a\nhref="${tpfx}t/#u">expand</a> ) .
+	my $expand = qq(<a\nhref="${tpfx}T/#u">expand</a> ) .
 			qq(/ <a\nhref="${tpfx}t.mbox.gz">mbox.gz</a> ) .
 			qq(/ <a\nhref="${tpfx}t.atom">Atom feed</a>);
 
 	my $parent = in_reply_to($hdr);
+	$$dst .= "\n<b>Thread overview: </b>";
 	if ($nr <= 1) {
 		if (defined $parent) {
 			$$dst .= "($expand)\n ";
@@ -440,9 +586,9 @@ sub _parent_headers {
 
 	my $irt = in_reply_to($hdr);
 	if (defined $irt) {
-		my $v = PublicInbox::Hval->new_msgid($irt, 1);
+		my $v = PublicInbox::Hval->new_msgid($irt);
 		my $html = $v->as_html;
-		my $href = $v->as_href;
+		my $href = $v->{href};
 		$rv .= "In-Reply-To: &lt;";
 		$rv .= "<a\nhref=\"../$href/\">$html</a>&gt;\n";
 	}
@@ -500,15 +646,15 @@ sub mailto_arg_link {
 	my $subj = $hdr->header('Subject') || '';
 	$subj = "Re: $subj" unless $subj =~ /\bRe:/i;
 	my $mid = $hdr->header_raw('Message-ID');
-	push @arg, '--in-reply-to='.ascii_html(squote_maybe(mid_clean($mid)));
-	my $irt = uri_escape_utf8($mid);
+	push @arg, '--in-reply-to='.squote_maybe(mid_clean($mid));
+	my $irt = mid_escape($mid);
 	delete $cc{$to};
-	push @arg, '--to=' . ascii_html($to);
+	push @arg, "--to=$to";
 	$to = uri_escape_utf8($to);
 	$subj = uri_escape_utf8($subj);
-	my $cc = join(',', sort values %cc);
-	push @arg, '--cc=' . ascii_html($cc);
-	$cc = uri_escape_utf8($cc);
+	my @cc = sort values %cc;
+	push(@arg, map { "--cc=$_" } @cc);
+	my $cc = uri_escape_utf8(join(',', @cc));
 	my $href = "mailto:$to?In-Reply-To=$irt&Cc=${cc}&Subject=$subj";
 	$href =~ s/%20/+/g;
 
@@ -526,21 +672,35 @@ sub html_footer {
 	if ($idx && $srch) {
 		$idx .= "\n";
 		thread_skel(\$idx, $ctx, $hdr, $tpfx);
-		my $p = $ctx->{parent_msg};
-		my $next = $ctx->{next_msg};
-		if ($p) {
-			$p = PublicInbox::Hval->new_msgid($p);
-			$p = $p->as_href;
-			$irt = "<a\nhref=\"$upfx$p/\"\nrel=prev>parent</a> ";
-		} else {
-			$irt = ' ' x length('parent ');
+		my ($next, $prev);
+		my $parent = '       ';
+		$next = $prev = '    ';
+
+		if (my $n = $ctx->{next_msg}) {
+			$n = PublicInbox::Hval->new_msgid($n)->{href};
+			$next = "<a\nhref=\"$upfx$n/\"\nrel=next>next</a>";
 		}
-		if ($next) {
-			my $n = PublicInbox::Hval->new_msgid($next)->as_href;
-			$irt .= "<a\nhref=\"$upfx$n/\"\nrel=next>next</a> ";
-		} else {
-			$irt .= ' ' x length('next ');
+		my $u;
+		my $par = $ctx->{parent_msg};
+		if ($par) {
+			$u = PublicInbox::Hval->new_msgid($par)->{href};
+			$u = "$upfx$u/";
+		}
+		if (my $p = $ctx->{prev_msg}) {
+			$prev = PublicInbox::Hval->new_msgid($p)->{href};
+			if ($p && $par && $p eq $par) {
+				$prev = "<a\nhref=\"$upfx$prev/\"\n" .
+					'rel=prev>prev parent</a>';
+				$parent = '';
+			} else {
+				$prev = "<a\nhref=\"$upfx$prev/\"\n" .
+					'rel=prev>prev</a>';
+				$parent = " <a\nhref=\"$u\">parent</a>" if $u;
+			}
+		} elsif ($u) { # unlikely
+			$parent = " <a\nhref=\"$u\"\nrel=prev>parent</a>";
 		}
+		$irt = "$next $prev$parent ";
 	} else {
 		$irt = '';
 	}
@@ -550,9 +710,9 @@ sub html_footer {
 }
 
 sub linkify_ref_nosrch {
-	my $v = PublicInbox::Hval->new_msgid($_[0], 1);
+	my $v = PublicInbox::Hval->new_msgid($_[0]);
 	my $html = $v->as_html;
-	my $href = $v->as_href;
+	my $href = $v->{href};
 	"&lt;<a\nhref=\"../$href/\">$html</a>&gt;";
 }
 
@@ -563,11 +723,9 @@ sub anchor_for {
 
 sub ghost_parent {
 	my ($upfx, $mid) = @_;
-	# 'subject dummy' is used internally by Mail::Thread
-	return '[no common parent]' if ($mid eq 'subject dummy');
 
 	$mid = PublicInbox::Hval->new_msgid($mid);
-	my $href = $mid->as_href;
+	my $href = $mid->{href};
 	my $html = $mid->as_html;
 	qq{[parent not found: &lt;<a\nhref="$upfx$href/">$html</a>&gt;]};
 }
@@ -591,8 +749,8 @@ sub msg_timestamp {
 
 sub thread_results {
 	my ($msgs) = @_;
-	require PublicInbox::Thread;
-	my $th = PublicInbox::Thread->new(@$msgs);
+	require PublicInbox::SearchThread;
+	my $th = PublicInbox::SearchThread->new($msgs);
 	$th->thread;
 	$th->order(*sort_ts);
 	$th
@@ -625,18 +783,17 @@ sub _skel_header {
 
 	if ($attr ne $ctx->{prev_attr} || $ctx->{prev_level} > $level) {
 		$ctx->{prev_attr} = $attr;
-	} else {
-		$attr = '';
 	}
 	$ctx->{prev_level} = $level;
 
 	if ($cur) {
 		if ($cur eq $mid) {
 			delete $ctx->{cur};
-			$$dst .= $d;
-			$$dst .= "<b><a\nid=r\nhref=\"#t\">".
+			$$dst .= "<b>$d<a\nid=r\nhref=\"#t\">".
 				 "$attr [this message]</a></b>\n";
 			return;
+		} else {
+			$ctx->{prev_msg} = $mid;
 		}
 	} else {
 		$ctx->{next_msg} ||= $mid;
@@ -654,7 +811,7 @@ sub _skel_header {
 		$s = PublicInbox::Hval->new($s);
 		$s = $s->as_html;
 	}
-	my $m = PublicInbox::Hval->new_msgid($mid);
+	my $m;
 	my $id = '';
 	my $mapping = $ctx->{mapping};
 	my $end = defined($s) ? "$s</a> $f\n" : "$f</a>\n";
@@ -665,7 +822,7 @@ sub _skel_header {
 		$map->[1] = "$d<a\nhref=\"$m\">$end";
 		$id = "\nid=r".$id;
 	} else {
-		$m = $ctx->{-upfx}.$m->as_href.'/';
+		$m = $ctx->{-upfx}.mid_escape($mid).'/';
 	}
 	$$dst .=  $d . "<a\nhref=\"$m\"$id>" . $end;
 }
@@ -679,18 +836,12 @@ sub skel_dump {
 		my $dst = $ctx->{dst};
 		my $mapping = $ctx->{mapping};
 		my $map = $mapping->{$mid} if $mapping;
-		if ($mid eq 'subject dummy') {
-			my $ncp = "\t[no common parent]\n";
-			$map->[1] = $ncp if $map;
-			$$dst .= $ncp;
-			return;
-		}
 		my $d = $ctx->{pct} ? '    [irrelevant] ' # search result
 				    : '     [not found] ';
 		$d .= indent_for($level) . th_pfx($level);
 		my $upfx = $ctx->{-upfx};
 		my $m = PublicInbox::Hval->new_msgid($mid);
-		my $href = $upfx . $m->as_href . '/';
+		my $href = $upfx . $m->{href} . '/';
 		my $html = $m->as_html;
 
 		if ($map) {
@@ -718,102 +869,163 @@ sub _tryload_ghost ($$) {
 }
 
 # accumulate recent topics if search is supported
-# returns 1 if done, undef if not
-sub add_topic {
+# returns 200 if done, 404 if not
+sub acc_topic {
 	my ($ctx, $level, $node) = @_;
 	my $srch = $ctx->{srch};
 	my $mid = $node->messageid;
 	my $x = $node->message || _tryload_ghost($srch, $mid);
 	my ($subj, $ts);
+	my $topic;
 	if ($x) {
 		$x = $x->header_obj;
-		$subj = $x->header('Subject');
+		$subj = $x->header('Subject') || '';
 		$subj = $srch->subject_normalized($subj);
 		$ts = $x->header('X-PI-TS');
-	} else { # ghost message, do not bump level
-		$ts = -666;
-		$subj = "<$mid>";
-	}
-	if (++$ctx->{subjs}->{$subj} == 1) {
-		push @{$ctx->{order}}, [ $level, $subj ];
-	}
-	my $exist = $ctx->{latest}->{$subj};
-	if (!$exist || $exist->[1] < $ts) {
-		$ctx->{latest}->{$subj} = [ $mid, $ts ];
+		if ($level == 0) {
+			$topic = [ $ts, 1, { $subj => $mid }, $subj ];
+			$ctx->{-cur_topic} = $topic;
+			push @{$ctx->{order}}, $topic;
+			return;
+		}
+
+		$topic = $ctx->{-cur_topic}; # should never be undef
+		$topic->[0] = $ts if $ts > $topic->[0];
+		$topic->[1]++;
+		my $seen = $topic->[2];
+		if (scalar(@$topic) == 3) { # parent was a ghost
+			push @$topic, $subj;
+		} elsif (!$seen->{$subj}) {
+			push @$topic, $level, $subj;
+		}
+		$seen->{$subj} = $mid; # latest for subject
+	} else { # ghost message
+		return if $level != 0; # ignore child ghosts
+		$topic = [ -666, 0, {} ];
+		$ctx->{-cur_topic} = $topic;
+		push @{$ctx->{order}}, $topic;
 	}
 }
 
-sub emit_topics {
+sub dump_topics {
 	my ($ctx) = @_;
-	my $order = $ctx->{order};
-	my $subjs = $ctx->{subjs};
-	my $latest = $ctx->{latest};
-	my $fh = $ctx->{fh};
-	return $fh->write("\n[No topics in range]</pre>") unless scalar @$order;
-	my $pfx;
-	my $prev = 0;
-	my $prev_attr = '';
-	my $cur;
-	my @recent;
-	while (defined(my $info = shift @$order)) {
-		my ($level, $subj) = @$info;
-		my $n = delete $subjs->{$subj};
-		my ($mid, $ts) = @{delete $latest->{$subj}};
-		$mid = PublicInbox::Hval->new_msgid($mid)->as_href;
-		$pfx = indent_for($level);
-		my $nl = $level == $prev ? "\n" : '';
-		if ($nl && $cur) {
-			push @recent, $cur;
-			$cur = undef;
-		}
-		$cur ||= [ $ts, '' ];
-		$cur->[0] = $ts if $ts > $cur->[0];
-		$cur->[1] .= $nl . $pfx . th_pfx($level);
-		if ($ts == -666) { # ghost
-			$cur->[1] .= ghost_parent('', $mid) . "\n";
-			next; # child will have mbox / atom link
-		}
+	my $order = delete $ctx->{order}; # [ ts, subj1, subj2, subj3, ... ]
+	if (!@$order) {
+		$ctx->{-html_tip} = '<pre>[No topics in range]</pre>';
+		return 404;
+	}
+
+	my @out;
 
-		$subj = PublicInbox::Hval->new($subj)->as_html;
-		$cur->[1] .= "<a\nhref=\"$mid/t/#u\"><b>$subj</b></a>\n";
+	# sort by recency, this allows new posts to "bump" old topics...
+	foreach my $topic (sort { $b->[0] <=> $a->[0] } @$order) {
+		my ($ts, $n, $seen, $top, @ex) = @$topic;
+		@$topic = ();
+		next unless defined $top;  # ghost topic
+		my $mid = delete $seen->{$top};
+		my $href = mid_escape($mid);
+		$top = PublicInbox::Hval->new($top)->as_html;
 		$ts = fmt_ts($ts);
-		my $attr = " $ts UTC";
 
 		# $n isn't the total number of posts on the topic,
 		# just the number of posts in the current results window
-		$n = $n == 1 ? '' : " ($n+ messages)";
-
-		if ($level == 0 || $attr ne $prev_attr) {
-			my $mbox = qq(<a\nhref="$mid/t.mbox.gz">mbox.gz</a>);
-			my $atom = qq(<a\nhref="$mid/t.atom">Atom</a>);
-			$pfx .= INDENT if $level > 0;
-			$cur->[1] .= $pfx . $attr . $n . " - $mbox / $atom\n";
-			$prev_attr = $attr;
+		my $anchor;
+		if ($n == 1) {
+			$n = '';
+			$anchor = '#u'; # top of only message
+		} else {
+			$n = " ($n+ messages)";
+			$anchor = '#t'; # thread skeleton
+		}
+
+		my $mbox = qq(<a\nhref="$href/t.mbox.gz">mbox.gz</a>);
+		my $atom = qq(<a\nhref="$href/t.atom">Atom</a>);
+		my $s = "<a\nhref=\"$href/T/$anchor\"><b>$top</b></a>\n" .
+			" $ts UTC $n - $mbox / $atom\n";
+		for (my $i = 0; $i < scalar(@ex); $i += 2) {
+			my $level = $ex[$i];
+			my $sub = $ex[$i + 1];
+			$mid = delete $seen->{$sub};
+			$sub = PublicInbox::Hval->new($sub)->as_html;
+			$href = mid_escape($mid);
+			$s .= indent_for($level) . TCHILD;
+			$s .= "<a\nhref=\"$href/T/#u\">$sub</a>\n";
 		}
+		push @out, $s;
 	}
-	push @recent, $cur if $cur;
-	@recent = map { $_->[1] } sort { $b->[0] <=> $a->[0] } @recent;
-	$fh->write(join('', @recent) . '</pre>');
+	$ctx->{-html_tip} = '<pre>' . join("\n", @out) . '</pre>';
+	200;
 }
 
-sub emit_index_topics {
+sub index_nav { # callback for WwwStream
+	my (undef, $ctx) = @_;
+	delete $ctx->{qp} or return;
+	my ($next, $prev);
+	$next = $prev = '    ';
+	my $latest = '';
+
+	my $next_o = $ctx->{-next_o};
+	if ($next_o) {
+		$next = qq!<a\nhref="?o=$next_o"\nrel=next>next</a>!;
+	}
+	if (my $cur_o = $ctx->{-cur_o}) {
+		$latest = qq! <a\nhref=.>latest</a>!;
+
+		my $o = $cur_o - ($next_o - $cur_o);
+		if ($o > 0) {
+			$prev = qq!<a\nhref="?o=$o"\nrel=prev>prev</a>!;
+		} elsif ($o == 0) {
+			$prev = qq!<a\nhref=.\nrel=prev>prev</a>!;
+		}
+	}
+	"<hr><pre>page: $next $prev$latest</pre>";
+}
+
+sub index_topics {
 	my ($ctx) = @_;
-	my ($off) = (($ctx->{cgi}->param('o') || '0') =~ /(\d+)/);
+	my ($off) = (($ctx->{qp}->{o} || '0') =~ /(\d+)/);
+	my $opts = { offset => $off, limit => 200 };
+
 	$ctx->{order} = [];
-	$ctx->{subjs} = {};
-	$ctx->{latest} = {};
-	my $max = 25;
-	my %opts = ( offset => $off, limit => $max * 4 );
-	while (scalar @{$ctx->{order}} < $max) {
-		my $sres = $ctx->{srch}->query('', \%opts);
-		my $nr = scalar @{$sres->{msgs}} or last;
+	my $sres = $ctx->{srch}->query('', $opts);
+	my $nr = scalar @{$sres->{msgs}};
+	if ($nr) {
 		$sres = load_results($sres);
-		walk_thread(thread_results($sres), $ctx, *add_topic);
-		$opts{offset} += $nr;
+		walk_thread(thread_results($sres), $ctx, *acc_topic);
 	}
+	$ctx->{-next_o} = $off+ $nr;
+	$ctx->{-cur_o} = $off;
+	PublicInbox::WwwStream->response($ctx, dump_topics($ctx), *index_nav);
+}
+
+sub thread_adj_level {
+	my ($ctx, $level) = @_;
+
+	my $max = $ctx->{cur_level};
+	if ($level <= 0) {
+		return ('', '') if $max == 0; # flat output
+
+		# reset existing lists
+		my $beg = $max > 1 ? ('</ul></li>' x ($max - 1)) : '';
+		$ctx->{cur_level} = 0;
+		("$beg</ul>", '');
+	} elsif ($level == $max) { # continue existing list
+		qw(<li> </li>);
+	} elsif ($level < $max) {
+		my $beg = $max > 1 ? ('</ul></li>' x ($max - $level)) : '';
+		$ctx->{cur_level} = $level;
+		("$beg<li>", '</li>');
+	} else { # ($level > $max) # start a new level
+		$ctx->{cur_level} = $level;
+		my $beg = ($max ? '<li>' : '') . '<ul><li>';
+		($beg, '</li>');
+	}
+}
 
-	emit_topics($ctx);
-	$opts{offset};
+sub ghost_index_entry {
+	my ($ctx, $level, $mid) = @_;
+	my ($beg, $end) = thread_adj_level($ctx,  $level);
+	$beg . '<pre>'. ghost_parent($ctx->{-upfx}, $mid) . '</pre>' . $end;
 }
 
 1;