X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSearchThread.pm;h=00ae9faccc08b7b16aff259fb9cd54165b485eb2;hb=4eee5af6011cc8cdefb66c9729952c7eff5c0b0b;hp=7e89946df81bd695ab7b14251cf2eae1ae346653;hpb=770c3c93b8a6a0db9e2152a67bccb257fa7c0233;p=public-inbox.git

diff --git a/lib/PublicInbox/SearchThread.pm b/lib/PublicInbox/SearchThread.pm
index 7e89946d..00ae9fac 100644
--- a/lib/PublicInbox/SearchThread.pm
+++ b/lib/PublicInbox/SearchThread.pm
@@ -4,10 +4,10 @@
 # This license differs from the rest of public-inbox
 #
 # Our own jwz-style threading class based on Mail::Thread from CPAN.
-# Mail::Thread is unmaintained and available on some distros.
+# Mail::Thread is unmaintained and unavailable on some distros.
 # We also do not want pruning or subject grouping, since we want
 # to encourage strict threading and hopefully encourage people
-# to use proper In-Reply-To.
+# to use proper In-Reply-To/References.
 #
 # This includes fixes from several open bugs for Mail::Thread
 #
@@ -20,53 +20,45 @@
 package PublicInbox::SearchThread;
 use strict;
 use warnings;
-
-sub new {
-	return bless {
-		messages => $_[1],
-		id_table => {},
-		rootset  => []
-	}, $_[0];
-}
+use PublicInbox::MID qw($MID_EXTRACT);
 
 sub thread {
-	my $self = shift;
-	$self->_setup();
-	$self->{rootset} = [
-			grep { !$_->{parent} } values %{$self->{id_table}} ];
-	$self->_finish();
-}
-
-sub _finish {
-	my $self = shift;
-	delete $self->{id_table};
-	delete $self->{seen};
-}
-
-sub _get_cont_for_id ($$) {
-	my ($self, $mid) = @_;
-	$self->{id_table}{$mid} ||= PublicInbox::SearchThread::Msg->new($mid);
-}
-
-sub _setup {
-	my ($self) = @_;
-
-	_add_message($self, $_) foreach @{$self->{messages}};
-}
-
-sub _add_message ($$) {
-	my ($self, $smsg) = @_;
-
-	# A. if id_table...
-	my $this = _get_cont_for_id($self, $smsg->{mid});
-	$this->{smsg} = $smsg;
-
-	# B. For each element in the message's References field:
-	my $prev;
-	if (defined(my $refs = $smsg->{references})) {
-		foreach my $ref ($refs =~ m/<([^>]+)>/g) {
+	my ($msgs, $ordersub, $ctx) = @_;
+	my (%id_table, @imposters);
+	keys(%id_table) = scalar @$msgs; # pre-size
+
+	# A. put all current non-imposter $msgs (non-ghosts) into %id_table
+	# (imposters are messages with reused Message-IDs)
+	# Sadly, we sort here anyways since the fill-in-the-blanks References:
+	# can be shakier if somebody used In-Reply-To with multiple, disparate
+	# messages.  So, take the client Date: into account since we can't
+	# always determine ordering when somebody uses multiple In-Reply-To.
+	my @kids = sort { $a->{ds} <=> $b->{ds} } grep {
+		# this delete saves around 4K across 1K messages
+		# TODO: move this to a more appropriate place, breaks tests
+		# if we do it during psgi_cull
+		delete $_->{num};
+		bless $_, 'PublicInbox::SearchThread::Msg';
+		if (exists $id_table{$_->{mid}}) {
+			$_->{children} = [];
+			push @imposters, $_; # we'll deal with them later
+			undef;
+		} else {
+			$_->{children} = {}; # will become arrayref later
+			$id_table{$_->{mid}} = $_;
+			defined($_->{references});
+		}
+	} @$msgs;
+	for my $smsg (@kids) {
+		# This loop exists to help fill in gaps left from missing
+		# messages.  It is not needed in a perfect world where
+		# everything is perfectly referenced, only the last ref
+		# matters.
+		my $prev;
+		for my $ref ($smsg->{references} =~ m/$MID_EXTRACT/go) {
 			# Find a Container object for the given Message-ID
-			my $cont = _get_cont_for_id($self, $ref);
+			my $cont = $id_table{$ref} //=
+				PublicInbox::SearchThread::Msg::ghost($ref);
 
 			# Link the References field's Containers together in
 			# the order implied by the References header
@@ -83,195 +75,103 @@ sub _add_message ($$) {
 			}
 			$prev = $cont;
 		}
-	}
 
-	# C. Set the parent of this message to be the last element in
-	# References...
-	if ($prev && !$this->has_descendent($prev)) { # would loop
-		$prev->add_child($this)
+		# C. Set the parent of this message to be the last element in
+		# References.
+		if (defined $prev && !$smsg->has_descendent($prev)) {
+			$prev->add_child($smsg);
+		}
 	}
-}
-
-sub order {
-	my $self = shift;
-	my $ordersub = shift;
-
-	# make a fake root
-	my $root = _get_cont_for_id($self, 'fakeroot');
-	$root->add_child( $_ ) for @{ $self->{rootset} };
-
-	# sort it
-	$root->order_children( $ordersub );
-
-	# and untangle it
-	my $kids = $root->children;
-	$self->{rootset} = $kids;
-	$root->remove_child($_) for @$kids;
+	my $ibx = $ctx->{ibx};
+	my @rootset = grep { # n.b.: delete prevents cyclic refs
+			!delete($_->{parent}) && $_->visible($ibx)
+		} values %id_table;
+	$ordersub->(\@rootset);
+	$_->order_children($ordersub, $ctx) for @rootset;
+
+	# parent imposter messages with reused Message-IDs
+	unshift(@{$id_table{$_->{mid}}->{children}}, $_) for @imposters;
+	\@rootset;
 }
 
 package PublicInbox::SearchThread::Msg;
+use base qw(PublicInbox::Smsg);
+use strict;
+use warnings;
 use Carp qw(croak);
-use Scalar::Util qw(weaken);
 
-sub new { my $self = shift; bless { id => shift }, $self; }
+# declare a ghost smsg (determined by absence of {blob})
+sub ghost {
+	bless {
+		mid => $_[0],
+		children => {}, # becomes an array when sorted by ->order(...)
+	}, __PACKAGE__;
+}
+
+sub topmost {
+	my ($self) = @_;
+	my @q = ($self);
+	while (my $cont = shift @q) {
+		return $cont if $cont->{blob};
+		push @q, values %{$cont->{children}};
+	}
+	undef;
+}
 
 sub add_child {
 	my ($self, $child) = @_;
 	croak "Cowardly refusing to become my own parent: $self"
 	  if $self == $child;
 
-	if (grep { $_ == $child } @{$self->children}) {
-		# All is potentially correct with the world
-		weaken($child->{parent} = $self);
-		return;
-	}
-
-	my $parent = $child->{parent};
-	remove_child($parent, $child) if $parent;
-
-	$child->{next} = $self->{child};
-	$self->{child} = $child;
-	weaken($child->{parent} = $self);
-}
+	my $cid = $child->{mid};
 
-sub remove_child {
-	my ($self, $child) = @_;
-
-	my $x = $self->{child} or return;
-	if ($x == $child) {  # First one's easy.
-		$self->{child} = $child->{next};
-		$child->{parent} = $child->{next} = undef;
-		return;
+	# reparenting:
+	if (defined(my $parent = $child->{parent})) {
+		delete $parent->{children}->{$cid};
 	}
 
-	my $prev = $x;
-	while ($x = $x->{next}) {
-		if ($x == $child) {
-			$prev->{next} = $x->{next}; # Unlink x
-			$x->{next} = $x->{parent} = undef; # Deparent it
-			return;
-		}
-		$prev = $x;
-	}
-	# oddly, we can get here
-	$child->{next} = $child->{parent} = undef;
+	$self->{children}->{$cid} = $child;
+	$child->{parent} = $self;
 }
 
 sub has_descendent {
-	my $self = shift;
-	my $child = shift;
-	die "Assertion failed: $child" unless eval {$child};
-	my $there = 0;
-	$self->recurse_down(sub { $there = 1 if $_[0] == $child });
-
-	return $there;
-}
-
-sub children {
-	my $self = shift;
-	my @children;
-	my $visitor = $self->{child};
-	while ($visitor) {
-		push @children, $visitor;
-		$visitor = $visitor->{next};
+	my ($self, $child) = @_;
+	my %seen; # loop prevention
+	while ($child) {
+		return 1 if $self == $child || $seen{$child}++;
+		$child = $child->{parent};
 	}
-	\@children;
+	0;
 }
 
-sub set_children {
-	my ($self, $children) = @_;
-	my $walk = $self->{child} = shift @$children;
-	do {
-		$walk = $walk->{next} = shift @$children;
-	} while ($walk);
-}
-
-sub order_children {
-	my $self = shift;
-	my $ordersub = shift;
-
-	return unless $ordersub;
-
-	my $sub = sub {
-		my $cont = shift;
-		my $children = $cont->children;
-		return if @$children < 2;
-		$cont->set_children( $ordersub->( $children ) );
-	};
-	$self->iterate_down( undef, $sub );
-	undef $sub;
-}
-
-# non-recursive version of recurse_down to avoid stack depth warnings
-sub recurse_down {
-	my ($self, $callback) = @_;
-	my %seen;
-	my @q = ($self);
-	while (my $cont = shift @q) {
-		$seen{$cont}++;
-		$callback->($cont);
-
-		if (my $next = $cont->{next}) {
-			if ($seen{$next}) {
-				$cont->{next} = undef;
-			} else {
-				push @q, $next;
-			}
-		}
-		if (my $child = $cont->{child}) {
-			if ($seen{$child}) {
-				$cont->{child} = undef;
-			} else {
-				push @q, $child;
-			}
-		}
+# Do not show/keep ghosts iff they have no children.  Sometimes
+# a ghost Message-ID is the result of a long header line
+# being folded/mangled by a MUA, and not a missing message.
+sub visible ($$) {
+	my ($self, $ibx) = @_;
+	return 1 if $self->{blob};
+	if (my $by_mid = $ibx->smsg_by_mid($self->{mid})) {
+		%$self = (%$self, %$by_mid);
+		1;
+	} else {
+		(scalar values %{$self->{children}});
 	}
 }
 
-sub iterate_down {
-	my $self = shift;
-	my ($before, $after) = @_;
-
-	my %seen;
-	my $walk = $self;
-	my $depth = 0;
-	my @visited;
-	while ($walk) {
-		push @visited, [ $walk, $depth ];
-		$before->($walk, $depth) if $before;
-
-		# spot/break loops
-		$seen{$walk}++;
-
-		my $child = $walk->{child};
-		if ($child && $seen{$child}) {
-			$walk->{child} = $child = undef;
-		}
-
-		my $next = $walk->{next};
-		if ($next && $seen{$next}) {
-			$walk->{next} = $next = undef;
-		}
-
-		# go down, or across
-		if ($child) {
-			$next = $child;
-			++$depth;
-		}
-
-		# no next?  look up
-		if (!$next) {
-			my $up = $walk;
-			while ($up && !$next) {
-				$up = $up->{parent};
-				--$depth;
-				$next = $up->{next} if $up;
-			}
-		}
-		$walk = $next;
+sub order_children {
+	my ($cur, $ordersub, $ctx) = @_;
+
+	my %seen = ($cur => 1); # self-referential loop prevention
+	my @q = ($cur);
+	my $ibx = $ctx->{ibx};
+	while (defined($cur = shift @q)) {
+		# the {children} hashref here...
+		my @c = grep { !$seen{$_}++ && visible($_, $ibx) }
+			values %{delete $cur->{children}};
+		$ordersub->(\@c) if scalar(@c) > 1;
+		$cur->{children} = \@c; # ...becomes an arrayref
+		push @q, @c;
 	}
-	return unless $after;
-	while (@visited) { $after->(@{ pop @visited }) }
 }
 
 1;