X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSearchThread.pm;h=450a06f43bc86f6266d32811e6efd507ffe94c7a;hb=ec2df4c3b80104a0bf15b0d917d82264bbf9b50e;hp=153eef2b32176412efd85cd3f007d70a1e3d3465;hpb=728d8dbcb920cd19f2fe4d7479d770c540274690;p=public-inbox.git

diff --git a/lib/PublicInbox/SearchThread.pm b/lib/PublicInbox/SearchThread.pm
index 153eef2b..450a06f4 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
 #
@@ -21,217 +21,135 @@ package PublicInbox::SearchThread;
 use strict;
 use warnings;
 
-sub new {
-	return bless {
-		messages => $_[1],
-		id_table => {},
-		rootset  => []
-	}, $_[0];
-}
-
 sub thread {
-	my $self = shift;
-	_add_message($self, $_) foreach @{$self->{messages}};
-	$self->{rootset} = [
-			grep { !$_->{parent} } values %{$self->{id_table}} ];
-	delete $self->{id_table};
+	my ($messages, $ordersub, $ibx) = @_;
+	my $id_table = {};
+	_add_message($id_table, $_) foreach @$messages;
+	my $rootset = [ grep {
+			!delete($_->{parent}) && $_->visible($ibx)
+		} values %$id_table ];
+	$id_table = undef;
+	$rootset = $ordersub->($rootset);
+	$_->order_children($ordersub, $ibx) for @$rootset;
+	$rootset;
 }
 
 sub _get_cont_for_id ($$) {
-	my ($self, $mid) = @_;
-	$self->{id_table}{$mid} ||= PublicInbox::SearchThread::Msg->new($mid);
+	my ($id_table, $mid) = @_;
+	$id_table->{$mid} ||= PublicInbox::SearchThread::Msg->new($mid);
 }
 
 sub _add_message ($$) {
-	my ($self, $smsg) = @_;
+	my ($id_table, $smsg) = @_;
 
 	# A. if id_table...
-	my $this = _get_cont_for_id($self, $smsg->{mid});
+	my $this = _get_cont_for_id($id_table, $smsg->{mid});
 	$this->{smsg} = $smsg;
 
 	# B. For each element in the message's References field:
+	defined(my $refs = $smsg->{references}) or return;
+
+	# 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;
-	if (defined(my $refs = $smsg->{references})) {
-		foreach my $ref ($refs =~ m/<([^>]+)>/g) {
-			# Find a Container object for the given Message-ID
-			my $cont = _get_cont_for_id($self, $ref);
-
-			# Link the References field's Containers together in
-			# the order implied by the References header
-			#
-			# * If they are already linked don't change the
-			#   existing links
-			# * Do not add a link if adding that link would
-			#   introduce a loop...
-			if ($prev &&
-				!$cont->{parent} &&  # already linked
-				!$cont->has_descendent($prev) # would loop
-			   ) {
-				$prev->add_child($cont);
-			}
-			$prev = $cont;
+	foreach my $ref ($refs =~ m/<([^>]+)>/g) {
+		# Find a Container object for the given Message-ID
+		my $cont = _get_cont_for_id($id_table, $ref);
+
+		# Link the References field's Containers together in
+		# the order implied by the References header
+		#
+		# * If they are already linked don't change the
+		#   existing links
+		# * Do not add a link if adding that link would
+		#   introduce a loop...
+		if ($prev &&
+			!$cont->{parent} &&  # already linked
+			!$cont->has_descendent($prev) # would loop
+		   ) {
+			$prev->add_child($cont);
 		}
+		$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)
+	# References.
+	if (defined $prev && !$this->has_descendent($prev)) { # would loop
+		$prev->add_child($this);
 	}
 }
 
-sub order {
-	my ($self, $ordersub) = @_;
-
-	# 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;
-}
-
 package PublicInbox::SearchThread::Msg;
+use strict;
+use warnings;
 use Carp qw(croak);
-use Scalar::Util qw(weaken);
 
-sub new { my $self = shift; bless { id => shift }, $self; }
+sub new {
+	bless {
+		id => $_[1],
+		children => {}, # becomes an array when sorted by ->order(...)
+	}, $_[0];
+}
+
+sub topmost {
+	my ($self) = @_;
+	my @q = ($self);
+	while (my $cont = shift @q) {
+		return $cont if $cont->{smsg};
+		push @q, values %{$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 $cid = $child->{id};
 
-	my $parent = $child->{parent};
-	remove_child($parent, $child) if $parent;
-
-	$child->{next} = $self->{child};
-	$self->{child} = $child;
-	weaken($child->{parent} = $self);
-}
-
-sub remove_child {
-	my ($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, $child) = @_;
-	my %seen;
-	my @q = ($self);
-	while (my $cont = shift @q) {
-		$seen{$cont} = 1;
-
-		return 1 if $cont == $child;
-
-		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, $child;
-			}
-		}
+	my %seen; # loop prevention
+	while ($child) {
+		return 1 if $self == $child || $seen{$child}++;
+		$child = $child->{parent};
 	}
 	0;
 }
 
-sub children {
-	my $self = shift;
-	my @children;
-	my $visitor = $self->{child};
-	while ($visitor) {
-		push @children, $visitor;
-		$visitor = $visitor->{next};
-	}
-	\@children;
-}
-
-sub set_children {
-	my ($self, $children) = @_;
-	my $walk = $self->{child} = shift @$children;
-	do {
-		$walk = $walk->{next} = shift @$children;
-	} while ($walk);
+# 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, $ibx) = @_;
+	($self->{smsg} ||= eval { $ibx->smsg_by_mid($self->{id}) }) ||
+	 (scalar values %{$self->{children}});
 }
 
 sub order_children {
-	my ($walk, $ordersub) = @_;
+	my ($cur, $ordersub, $ibx) = @_;
 
-	my %seen;
-	my @visited;
-	while ($walk) {
-		push @visited, $walk;
-
-		# spot/break loops
-		$seen{$walk} = 1;
-
-		my $child = $walk->{child};
-		if ($child && $seen{$child}) {
-			$walk->{child} = $child = undef;
-		}
+	my %seen = ($cur => 1); # self-referential loop prevention
+	my @q = ($cur);
+	while (defined($cur = shift @q)) {
+		my $c = $cur->{children}; # The hashref here...
 
-		my $next = $walk->{next};
-		if ($next && $seen{$next}) {
-			$walk->{next} = $next = undef;
-		}
-
-		# go down, or across
-		$next = $child if $child;
-
-		# no next?  look up
-		if (!$next) {
-			my $up = $walk;
-			while ($up && !$next) {
-				$up = $up->{parent};
-				$next = $up->{next} if $up;
-			}
-		}
-		$walk = $next;
-	}
-	foreach my $cont (@visited) {
-		my $children = $cont->children;
-		next if @$children < 2;
-		$children = $ordersub->($children);
-		$cont = $cont->{child} = shift @$children;
-		do {
-			$cont = $cont->{next} = shift @$children;
-		} while ($cont);
+		$c = [ grep { !$seen{$_}++ && visible($_, $ibx) } values %$c ];
+		$c = $ordersub->($c) if scalar @$c > 1;
+		$cur->{children} = $c; # ...becomes an arrayref
+		push @q, @$c;
 	}
 }