X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2FID3FS%2FPath.pm;h=de8d63bc8e2567878708ab89183c370c36c52e6f;hb=a461a5fca9a1ffc9e54c978423214c2fa59431e5;hp=60ea5de43b498e1fe30c64dcbf81cb11be0b1977;hpb=d37f9e03d8acde3100e40874535f860eaa15582b;p=id3fs.git

diff --git a/lib/ID3FS/Path.pm b/lib/ID3FS/Path.pm
index 60ea5de..de8d63b 100644
--- a/lib/ID3FS/Path.pm
+++ b/lib/ID3FS/Path.pm
@@ -1,24 +1,36 @@
+# id3fs - a FUSE-based filesystem for browsing audio metadata
+# Copyright (C) 2010  Ian Beckwith <ianb@erislabs.net>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
 package ID3FS::Path;
 
 use strict;
 use warnings;
-use ID3FS::PathElement::Artist;
-use ID3FS::PathElement::Album;
-use ID3FS::PathElement::Boolean;
-use ID3FS::PathElement::File;
-use ID3FS::PathElement::Tag;
-use ID3FS::PathElement::Tagval;
 use ID3FS::Path::Node;
 
-our ($STATE_INVALID, $STATE_ROOT, $STATE_TAG, $STATE_TAGVAL,
-     $STATE_BOOLEAN, $STATE_ALBUMS, $STATE_TRACKLIST,
-     $STATE_FILE, $STATE_ALL)=(0..8);
+our ($STATE_INVALID, $STATE_ROOT, $STATE_TAG, $STATE_BOOLEAN,
+     $STATE_ALBUMS, $STATE_TRACKLIST, $STATE_FILE, $STATE_ALL)=(0..7);
 
+# operator precedence
 our %priorities=( "OR" => 0, "AND" => 1, "NOT" => 2 );
 
-our $PATH_ALLTRACKS="TRACKS";
-our $PATH_NOARTIST="NOARTIST";
-our $PATH_NOALBUM="NOALBUM";
+our $PATH_ALLTRACKS= "TRACKS";
+our $PATH_NOARTIST = "NOARTIST";
+our $PATH_NOALBUM  = "NOALBUM";
+
+our $ENABLE_FILTER = 0;
 
 sub new
 {
@@ -31,6 +43,8 @@ sub new
     $self->{db}=shift;
     $self->{path}=shift;
     $self->{verbose}=shift;
+    $self->{maxtagdepth}=shift;
+    $self->{curtagdepth}=0;
     $self->{path} =~ s/\/\//\//g; # drop doubled slashes
 
     $self->parse();
@@ -52,8 +66,7 @@ sub isdir
 sub isfile
 {
     my($self)=@_;
-    return 1 if($self->state() == $STATE_FILE);
-    return 0;
+    return($self->state() == $STATE_FILE);
 }
 
 sub isvalid
@@ -67,7 +80,7 @@ sub dest
     my($self, $mountpoint)=@_;
     if($self->state() == $STATE_FILE)
     {
-	return $self->filename($mountpoint, $self);
+	return $self->filename($mountpoint);
     }
     return "ERROR"; #should never happen?
 }
@@ -82,41 +95,40 @@ sub dirents
 #    print "DIRENTS: FILE: $self->{path}\n";
     if($state==$STATE_ALL)
     {
-	@dents=($self->artists(), $PATH_ALLTRACKS, $PATH_NOARTIST);
+	@dents=($self->filter($PATH_ALLTRACKS, $PATH_NOARTIST), $self->artists());
     }
-    elsif($state==$STATE_TAG || $state==$STATE_TAGVAL)
+    elsif($state==$STATE_TAG)
     {
-	my $tag=$self->tail();
-	if($state==$STATE_TAG &&
-	   defined($tag) &&
-	   ref($tag) eq "ID3FS::PathElement::Tag" &&
-	   $self->{db}->tag_has_values($tag->{id}))
+	my $tail=$self->tail();
+	if($self->is($TYPE_TAG, $tail) && $self->{db}->tag_has_values($tail->id()))
 	{
 	    @dents=$self->tags();
 	}
 	else
 	{
-	    @dents=($self->artists(), qw(AND OR), $PATH_ALLTRACKS, $PATH_NOARTIST);
+	    if($self->{maxtagdepth} && ($self->{curtagdepth} < $self->{maxtagdepth}))
+	    {
+		@dents=qw(AND OR);
+	    }
+	    push(@dents, $self->filter($PATH_ALLTRACKS, $PATH_NOARTIST), $self->artists());
 	}
     }
     elsif($state==$STATE_BOOLEAN)
     {
-	@dents=$self->tags();
 	my $parent=$self->tail();
-	unless(defined($parent) &&
-	       ref($parent) eq "ID3FS::PathElement::Boolean" &&
-	       $parent->{name} eq "NOT")
+	unless($self->is($TYPE_BOOL, $parent) && $parent->name() eq "NOT")
 	{
-	    push(@dents, "NOT");
+	    @dents=("NOT");
 	}
+	push(@dents,$self->tags());
     }
     elsif($state==$STATE_ROOT)
     {
-	@dents=($self->tags(), qw(ALL NOT));
+	@dents=(qw(ALL NOT), $self->tags());
     }
     elsif($state==$STATE_ALBUMS)
     {
-	@dents=($self->albums(), $PATH_ALLTRACKS, $PATH_NOALBUM);
+	@dents=$self->filter($PATH_ALLTRACKS, $PATH_NOALBUM, $self->albums());
     }
     elsif($state==$STATE_TRACKLIST)
     {
@@ -124,23 +136,23 @@ sub dirents
     }
     else
     {
-	print "DIRENTS: UNHANDLED STATE: $state\n";
+	print "id3fsd: INTERNAL ERROR: DIRENTS: UNHANDLED STATE: $state\n";
     }
     return(\@dents, \@fents);
 }
 
+# State Machine Of Doom
 sub parse
 {
     my($self)=@_;
+    $self->state($STATE_ROOT);
+    return if($self->{path} eq "/");
     @{$self->{components}}=split(/\//, $self->{path});
     shift @{$self->{components}}; # drop empty field before leading /
 #    print "PATH: $self->{path}\n";
-    $self->state($STATE_ROOT);
-    return if($self->{path} eq "/");
     my @parts=@{$self->{components}};
     my($tag, $tagval);
     $self->{elements}=[];
-    $self->{bare_not}=0;
     $self->{in_all}=0;
     my $root_not=0;
     my $tags_seen=0;
@@ -164,12 +176,12 @@ sub parse
 	    elsif($name eq "NOT")
 	    {
 		$root_not=1;
-	        push(@{$self->{elements}}, ID3FS::PathElement::Boolean->new($self->{db}, $name));
+	        push(@{$self->{elements}}, ID3FS::Path::Node->new($self->{db}, $TYPE_BOOL, $name));
 		$self->state($STATE_BOOLEAN);
 	    }
 	    else
 	    {
-		$tag=ID3FS::PathElement::Tag->new($self->{db}, $name);
+		$tag=ID3FS::Path::Node->new($self->{db}, $TYPE_TAG, $name);
 		if($tag)
 		{
 		    push(@{$self->{elements}}, $tag);
@@ -182,20 +194,16 @@ sub parse
 		}
 	    }
 	}
-	elsif($state==$STATE_TAG || $state==$STATE_TAGVAL)
+	elsif($state==$STATE_TAG)
 	{
-#	    print "SM: TAG/TAGVAL($state): $name\n";
 	    my $tag=$self->tail();
-	    if($state==$STATE_TAG &&
-	       defined($tag) &&
-	       ref($tag) eq "ID3FS::PathElement::Tag" &&
-	       $self->{db}->tag_has_values($tag->{id}))
+#	    print "SM: TAG/TAGVAL($state): $name\n";
+	    if($self->is($TYPE_TAG, $tag) && $self->{db}->tag_has_values($tag->id()))
 	    {
-#		print "Parsing: parent: $tag->{id}\n";
-		my $tagval=ID3FS::PathElement::Tag->new($self->{db}, $name, $tag->{id});
+#		print "Parsing: parent: $tag->id()\n";
+		my $tagval=ID3FS::Path::Node->new($self->{db}, $TYPE_TAG, $name, $tag->id());
 		if(defined($tagval))
 		{
-		    $self->state($STATE_TAGVAL);
 		    # stay in tag state
 		    push(@{$self->{elements}}, $tagval);
 		}
@@ -215,16 +223,16 @@ sub parse
 	    elsif($name eq "AND")
 	    {
 		$self->state($STATE_BOOLEAN);
-	        push(@{$self->{elements}}, ID3FS::PathElement::Boolean->new($self->{db}, $name));
+	        push(@{$self->{elements}}, ID3FS::Path::Node->new($self->{db}, $TYPE_BOOL, $name));
 	    }
 	    elsif($name eq "OR")
 	    {
 		$self->state($STATE_BOOLEAN);
-	        push(@{$self->{elements}}, ID3FS::PathElement::Boolean->new($self->{db}, $name));
+	        push(@{$self->{elements}}, ID3FS::Path::Node->new($self->{db}, $TYPE_BOOL, $name));
 	    }
 	    else
 	    {
-		my $artist=ID3FS::PathElement::Artist->new($self->{db}, $name);
+		my $artist=ID3FS::Path::Node->new($self->{db}, $TYPE_ARTIST, $name);
 		if($artist)
 		{
 		    push(@{$self->{elements}}, $artist);
@@ -241,20 +249,19 @@ sub parse
 #	    print "SM: BOOLEAN: $name\n";
 	    my $parent=$self->tail();
 	    my $allownot=1;
-	    if(defined($parent) &&
-	       ref($parent) eq "ID3FS::PathElement::Boolean" &&
-	       $parent->{name} eq "NOT")
+	    if($self->is($TYPE_BOOL, $parent) &&
+	       $parent->name() eq "NOT")
 	    {
 		$allownot=0;
 	    }
 	    if($allownot && $name eq "NOT")
 	    {
 		$self->state($STATE_BOOLEAN);
-	        push(@{$self->{elements}}, ID3FS::PathElement::Boolean->new($self->{db}, $name));
+	        push(@{$self->{elements}}, ID3FS::Path::Node->new($self->{db}, $TYPE_BOOL, $name));
 	    }
 	    else
 	    {
-		my $tag=ID3FS::PathElement::Tag->new($self->{db}, $name);
+		my $tag=ID3FS::Path::Node->new($self->{db}, $TYPE_TAG, $name);
 		if($tag)
 		{
 		    push(@{$self->{elements}}, $tag);
@@ -280,7 +287,7 @@ sub parse
 	    }
 	    else
 	    {
-		my $album=ID3FS::PathElement::Album->new($self->{db}, $name);
+		my $album=ID3FS::Path::Node->new($self->{db}, $TYPE_ALBUM, $name);
 		if($album)
 		{
 		    push(@{$self->{elements}}, $album);
@@ -295,7 +302,7 @@ sub parse
 	elsif($state==$STATE_TRACKLIST)
 	{
 #	    print "SM: TRACKLIST: $name\n";
-	    my $track=ID3FS::PathElement::File->new($self->{db}, $name);
+	    my $track=ID3FS::Path::Node->new($self->{db}, $TYPE_FILE, $name);
 	    if($track)
 	    {
 		push(@{$self->{elements}}, $track);
@@ -320,12 +327,11 @@ sub parse
 	    }
 	    elsif($name eq $PATH_NOARTIST)
 	    {
-		# FIXME
 		$self->state($STATE_TRACKLIST);
 	    }
 	    else
 	    {
-		my $artist=ID3FS::PathElement::Artist->new($self->{db}, $name);
+		my $artist=ID3FS::Path::Node->new($self->{db}, $TYPE_ARTIST, $name);
 		if($artist)
 		{
 		    push(@{$self->{elements}}, $artist);
@@ -344,59 +350,114 @@ sub parse
 	}
     }
 
-    if($root_not && ($tags_seen < 2))
-    {
-	$self->{bare_not}=1;
-    }
-
-    # remove trailing boolean
     my @elements=@{$self->{elements}};
-    while(@elements && ref($elements[$#elements]) eq "ID3FS::PathElement::Boolean")
+    # remove trailing boolean
+    while(@elements && $self->is($TYPE_BOOL, $elements[$#elements]))
     {
 	pop @elements;
     }
+#    print "\nELEMENTS: ", join(' ', map { $_->name(); } @elements), "\n";
+    my @joins=$self->number_joins(@elements);
+    @joins=qw(INNER) unless(@joins);
+    $self->{joins}=\@joins;
+#    print "AFTER: ", join(' ', map { $_->name() . "(" . $_->{table} . ")"; } @elements), "\n";
+#    print "JOINS: ", join(', ', @joins), "\n";
     # sort elements by precedence
     @elements=$self->sort_elements(@elements);
     $self->{tagtree}=$self->elements_to_tree(\@elements);
-    if($self->{tagtree})
+}
+
+sub number_joins
+{
+    my($self, @elements)=@_;
+    my @joins=("INNER");
+    my $table=1;
+    my $nextjoin=undef;
+    my $lastop=undef;
+    return (@joins) unless(@elements);
+    while(my $node=shift @elements)
     {
-	($self->{sqlconditions},
-	 $self->{joins}) = $self->{tagtree}->to_sql();
-#	print "TREE: ",  $self->{tagtree}->print(), "\n";
-#	print("SQL CONDITION(", scalar(@{$self->{joins}}), "): ",
-#	      $self->{sqlconditions}, "\n");
-#	use Data::Dumper;
-#	print Dumper $self->{tagtree};
+	if($node->type() == $TYPE_BOOL)
+	{
+	    my $op=$node->name();
+	    if($op eq "AND")
+	    {
+		$nextjoin="INNER";
+	    }
+	    elsif($op eq "NOT")
+	    {
+		$nextjoin="LEFT";
+	    }
+	    elsif($op eq "OR")
+	    {
+		# NOT/foo/OR needs an extra join
+		$nextjoin="INNER" if($lastop && $lastop eq "NOT");
+	    }
+	    $lastop=$op;
+	}
+	else
+	{
+	    if(@elements)
+	    {
+		# if tag has a value, eat the tag, shifting to the value
+		if($elements[0]->type() == $TYPE_TAG)
+		{
+		    $node->hasvals(1);
+		    $node=shift(@elements);
+		}
+		else
+		{
+		    $node->hasvals(0);
+		}
+	    }
+	    elsif($self->{db}->tag_has_values($node->id()))
+	    {
+		# if the expression ends in a tag that has a value
+		# (ie we have the tag and want the value)
+		# use an INNER join even if we were in a NOT
+		$nextjoin="INNER" if($nextjoin);
+	    }
+	    if($nextjoin)
+	    {
+		$table++;
+		push(@joins, $nextjoin);
+		$nextjoin=undef;
+	    }
+	    $node->table($table);
+	}
     }
+    return @joins;
 }
 
 sub state
 {
     my($self, $newstate)=@_;
-    $self->{state}=$newstate if(defined($newstate));
+    if(defined($newstate))
+    {
+	$self->{state}=$newstate;
+	$self->{curtagdepth}++ if($newstate == $STATE_TAG);
+    }
     return $self->{state};
 }
 
+# link up precedence-sorted list into a binary tree
 sub elements_to_tree
 {
     my($self, $elements)=@_;
     return undef unless(@$elements);
     my ($left, $right, $op)=(undef, undef, undef);
-    my $thing=pop @$elements;
-    if(ref($thing) eq "ID3FS::PathElement::Boolean")
+    my $node=pop @$elements;
+    if($self->is($TYPE_BOOL, $node))
     {
-	my $op=$thing;
 	$right=$self->elements_to_tree($elements);
-	if($op->{name} ne "NOT")
+	if($node->name() ne "NOT")
 	{
 	    $left=$self->elements_to_tree($elements);
 	}
-	return ID3FS::Path::Node->new($left, $op, $right);
-    }
-    else
-    {
-	return ID3FS::Path::Node->new($thing);
+	$node->left($left);
+	$node->right($right);
     }
+    return $node;
 }
 
 # Dijkstra's shunting-yard algorithm
@@ -405,34 +466,31 @@ sub sort_elements
     my ($self, @input)=@_;
     my @opstack=();
     my @output=();
-#    print "INPUT: ", join(', ', map { $_->{name}; } @input), "\n";
-    while(my $thing = shift @input)
+    while(my $node = shift @input)
     {
-	if(ref($thing) eq "ID3FS::PathElement::Tag")
+	if($self->is($TYPE_TAG, $node))
 	{
 	    # Handle tag values by dropping parent
-	    if(@input && ref($input[0]) eq "ID3FS::PathElement::Tag")
+	    if(@input && $self->is($TYPE_TAG, $input[0]))
 	    {
-		$thing=shift @input;
+		$node=shift @input;
 	    }
-	    push(@output, $thing);
+	    push(@output, $node);
 	}
-	elsif(ref($thing) eq "ID3FS::PathElement::Boolean")
+	elsif($self->is($TYPE_BOOL, $node))
 	{
-	    # bool
 	    while(@opstack &&
-		  ($priorities{$thing->{name}} <= $priorities{$opstack[$#opstack]->{name}}))
+		  ($priorities{$node->name()} <= $priorities{$opstack[$#opstack]->name()}))
 	    {
 		push(@output, pop(@opstack));
 	    }
-	    push(@opstack, $thing);
+	    push(@opstack, $node);
 	}
     }
     while(@opstack)
     {
 	push(@output, pop(@opstack));
     }
-#    print "STACK: ", join(', ', map { $_->{name}; } @output), "\n";
     return @output;
 }
 
@@ -443,13 +501,13 @@ sub used_tags
     return($self->{tagtree}->used_tags());
 }
 
-sub tag_has_values
+sub expecting_values
 {
     my($self)=@_;
     my $tail=$self->tail();
-    if($tail && ref($tail) eq "ID3FS::PathElement::Tag")
+    if($self->is($TYPE_TAG, $tail))
     {
-	return($self->{db}->tag_has_values($tail->{id}));
+	return($self->{db}->tag_has_values($tail->id()));
     }
 }
 
@@ -457,9 +515,9 @@ sub trailing_tag_id
 {
     my($self)=@_;
     my $tail=$self->tail();
-    if($tail && ref($tail) eq "ID3FS::PathElement::Tag")
+    if($self->is($TYPE_TAG, $tail))
     {
-	return($tail->{id});
+	return($tail->id());
     }
     return undef;
 }
@@ -468,7 +526,7 @@ sub trailing_tag_parent
 {
     my($self)=@_;
     my $tail=$self->tail();
-    if($tail && ref($tail) eq "ID3FS::PathElement::Tag")
+    if($self->is($TYPE_TAG, $tail))
     {
 	return($tail->{parents_id});
     }
@@ -481,6 +539,15 @@ sub tail
     return($self->{elements}->[$#{$self->{elements}}]);
 }
 
+sub is
+{
+    my($self, $type, $node)=@_;
+    return 0 unless($node);
+    return 0 unless($node->type());
+    return 1 if($type == $node->type());
+    return 0;
+}
+
 # the one before last
 sub tail_parent
 {
@@ -493,74 +560,42 @@ sub tail_parent
 sub tags
 {
     my($self)=@_;
-    if(!$self->{tagtree}) # / or /NOT  # FIXME: /ALL too?
+    if(!$self->{tagtree}) # / or /NOT
     {
 	my $sql="SELECT DISTINCT name FROM tags WHERE parents_id='';";
 	return($self->{db}->cmd_firstcol($sql));
     }
-    my $hasvals=$self->tag_has_values();
-    my $parent=$self->trailing_tag_parent();
-#    print "THASVALS: $hasvals\n";
-#    print "TPARENT: ", (defined($parent)? $parent : "NO"), "\n";
-    my @ids=();
-    my $sql=("SELECT tags.name FROM (\n" .
-	     $self->tags_subselect() .
-	     ") AS subselect\n" .
-	     "INNER JOIN files_x_tags ON subselect.files_id=files_x_tags.files_id\n" .
-	     "INNER JOIN tags ON files_x_tags.tags_id=tags.id\n");
-    my @allused=$self->used_tags();
-    my @used=grep { ref($_) ne "ARRAY"; } @allused;
-    my @used_with_vals=grep { ref($_) eq "ARRAY"; } @allused;
-#    print "tags(): USED: ", join(", ", @used), "\n";
-#    print "tags(): USED_WITH_VALS: ", join(", ", map { "[".$_->[0]. ", ".$_->[1]."]";} @used_with_vals), "\n";
-    my @orclauses=();
-    my @andclauses=();
-    my $id=$self->trailing_tag_id();
-    if($hasvals)
+    my $sql="SELECT tags.name FROM ";
+    if($self->want_all_tags())
     {
-#	print "HAS_VALUES\n";
-	my @values=map { "'".$_->[1]."'"; } grep { $_->[0] == $id; } @used_with_vals;
-	my $clause="(tags.parents_id='$id'";
-	if(@values)
-	{
-	    $clause .= " AND tags.id NOT IN (" . join(', ', @values) . ")";
-	}
-	$clause .= ")";
-	push(@andclauses, $clause);
+	$sql .= "files_x_tags\n";
     }
     else
     {
-#	print "HASNT VALUES\n";;
-	if(@used)
-	{
-	    push(@andclauses, "(NOT (tags.parents_id='' AND tags.id IN (" . join(', ', @used) . ")))");
-	}
-	for my $pair (@used_with_vals)
-	{
-	    push(@andclauses, "(NOT (tags.parents_id='" . $pair->[0] . "' AND tags.id='" . $pair->[1] . "'))");
-	}
+	$sql .= ("(\n" .
+		 $self->tags_subselect() .
+		 ") AS subselect\n" .
+		 "INNER JOIN files_x_tags ON subselect.files_id=files_x_tags.files_id\n");
     }
+    $sql .= "INNER JOIN tags ON files_x_tags.tags_id=tags.id\n";
+    my @andclauses=();
+    my $id=$self->trailing_tag_id();
 
-    my $parentclause= "(tags.parents_id='";
-    if($hasvals)
-    {
-	$parentclause .= $id;
-    }
-    elsif($parent)
-    {
-	$parentclause .= $parent;
-    }
-    $parentclause .= "')";
+    my $parentclause= "tags.parents_id='";
+    $parentclause .= $id if($self->expecting_values());
+    $parentclause .= "'";
     push(@andclauses, $parentclause);
 
-    if(@orclauses)
+    my @used=$self->used_tags();
+    if(@used)
     {
-	push(@andclauses, '( ' . join(' OR ', @orclauses) . ' )');
+	push(@andclauses, "tags.id NOT IN (" . join(', ', @used) . ")");
     }
     if(@andclauses)
     {
 	$sql .= "WHERE " . join(' AND ', @andclauses) . "\n";
     }
+
     $sql .= "GROUP BY tags.name;";
     print "SQL(TAGS): $sql\n" if($self->{verbose});
     my @tagnames=$self->{db}->cmd_firstcol($sql);
@@ -568,16 +603,6 @@ sub tags
     return(@tagnames);
 }
 
-sub tag_values
-{
-    my($self, $tagid)=@_;
-    my $sql=("SELECT DISTINCT name FROM tags\n" .
-	     "WHERE parents_id=?");
-    my @tags=$self->{db}->cmd_firstcol($sql, $tagid);
-    @tags=map { length($_) ? $_ : "NOVALUE"; } @tags;
-    return @tags;
-}
-
 sub artists
 {
     my($self)=@_;
@@ -586,12 +611,8 @@ sub artists
 	my $sql="SELECT DISTINCT name FROM artists WHERE name!='';";
 	return($self->{db}->cmd_firstcol($sql));
     }
-    my @ids=();
-    my $sql=("SELECT artists.name FROM (\n" .
-	     $self->tags_subselect() .
-	     ") AS subselect\n" .
-	     "INNER JOIN files ON subselect.files_id=files.id\n" .
-	     "INNER JOIN artists ON files.artists_id=artists.id\n" .
+    my $sql=$self->sql_start("artists.name");
+    $sql .= ("INNER JOIN artists ON files.artists_id=artists.id\n" .
 	     "WHERE artists.name != ''\n" .
 	     "GROUP BY artists.name;");
     print "SQL(ARTISTS): $sql\n" if($self->{verbose});
@@ -603,29 +624,15 @@ sub artists
 sub albums
 {
     my($self)=@_;
-    my @ids=();
     my $tail=$self->tail();
-    # FIXME: rework PathElements
-    if(ref($tail) eq "ID3FS::PathElement::Artist")
-    {
-	return $self->artist_albums($tail->{id});
-    }
-    my $sql;
-    if($self->{in_all})
+    if($self->is($TYPE_ARTIST, $tail))
     {
-	$sql="SELECT name FROM albums";
-    }
-    else
-    {
-	$sql=("SELECT albums.name\n" .
-	      "\tFROM (\n" .
-	      $self->tags_subselect() .
-	      "\t) AS subselect\n" .
-	      "INNER JOIN files ON subselect.files_id=files.id\n" .
-	      "INNER JOIN albums ON files.albums_id=albums.id\n" .
-	      "WHERE albums.name != ''\n" .
-	      "GROUP BY albums.name;");
+	return $self->artist_albums($tail->id());
     }
+    my $sql=$self->sql_start("albums.name");
+    $sql .= ("INNER JOIN albums ON files.albums_id=albums.id\n" .
+	     "WHERE albums.name != ''\n" .
+	     "GROUP BY albums.name;");
     print "SQL(ALBUMS): \n$sql\n" if($self->{verbose});
     my @names=$self->{db}->cmd_firstcol($sql);
     print("ALBUMS: ", join(', ', @names), "\n") if($self->{verbose});
@@ -635,18 +642,7 @@ sub albums
 sub artist_albums
 {
     my($self, $artist_id)=@_;
-    my $sql="SELECT albums.name FROM ";
-    if($self->{in_all})
-    {
-	$sql .= "files\n";
-    }
-    else
-    {
-	$sql .= ("(\n" .
-		 $self->tags_subselect() .
-		 ") AS subselect\n" .
-		 "INNER JOIN files ON subselect.files_id=files.id\n");
-    }
+    my $sql=$self->sql_start("albums.name");
     $sql .= ("INNER JOIN albums ON albums.id=files.albums_id\n" .
 	     "INNER JOIN artists ON artists.id=files.artists_id\n" .
 	     "WHERE artists.id=? and albums.name <> ''\n" .
@@ -660,18 +656,7 @@ sub artist_albums
 sub artist_tracks
 {
     my($self, $artist_id)=@_;
-    my $sql="SELECT files.name FROM ";
-    if($self->{in_all})
-    {
-	$sql .= "files\n";
-    }
-    else
-    {
-	$sql .= ("(\n" .
-		 $self->tags_subselect() .
-		 "\t) AS subselect\n" .
-		 "INNER JOIN files ON subselect.files_id=files.id\n");
-    }
+    my $sql=$self->sql_start("files.name");
     $sql .= ("INNER JOIN artists ON artists.id=files.artists_id\n" .
 	     "INNER JOIN albums  ON albums.id=files.albums_id\n" .
 	     "WHERE artists.id=? AND albums.name=''\n" .
@@ -699,35 +684,23 @@ sub album_tracks
 sub tracks
 {
     my($self)=@_;
-    # FIXME: rework PathElements
     my $tail=$self->tail();
-    if(ref($tail) eq "ID3FS::PathElement::Artist")
+    if($self->is($TYPE_ARTIST, $tail))
     {
-	return $self->artist_tracks($tail->{id});
+	return $self->artist_tracks($tail->id());
     }
-    elsif(ref($tail) eq "ID3FS::PathElement::Album")
+    elsif($self->is($TYPE_ALBUM, $tail))
     {
 	my $artist_id=0;
 	my $artist=$self->tail_parent();
-	if(defined($artist) && (ref($artist) eq "ID3FS::PathElement::Artist"))
+	if($self->is($TYPE_ARTIST, $artist))
 	{
 	    # should always happen
-	    $artist_id=$artist->{id};
+	    $artist_id=$artist->id();
 	}
-	return $self->album_tracks($artist_id, $tail->{id});
-    }
-    my $sql="SELECT files.name FROM ";
-    if($self->{in_all})
-    {
-	$sql .= "files\n";
-    }
-    else
-    {
-	$sql .= ("(\n" .
-		 $self->tags_subselect() .
-		 ") AS subselect\n" .
-		 "INNER JOIN files ON files.id=subselect.files_id\n");
+	return $self->album_tracks($artist_id, $tail->id());
     }
+    my $sql=$self->sql_start("files.name");
     $sql .= "INNER JOIN artists ON files.artists_id=artists.id\n";
     if($self->{components}->[$#{$self->{components}}] eq $PATH_NOARTIST)
     {
@@ -744,53 +717,32 @@ sub filename
 {
     my($self, $mountpoint)=@_;
     my $tail=$self->tail();
-    if(ref($tail) eq "ID3FS::PathElement::File")
+    if($self->is($TYPE_FILE, $tail))
     {
-	my $id=$tail->{id};
+	my $id=$tail->id();
 	my $sql=("SELECT paths.name, files.name FROM files\n" .
 		 "INNER JOIN paths ON files.paths_id=paths.id\n" .
 		 "WHERE files.id=?\n" .
 		 "GROUP BY paths.name, files.name");
 	print "FILENAME SQL: $sql\n" if($self->{verbose});
 	my ($path, $name)=$self->{db}->cmd_onerow($sql, $id);
-	my $id3fs_path=join('/', map { $_->{name}; }  @{$self->{elements}});
-	return($self->{db}->relativise($path, $name, $mountpoint, $id3fs_path));
+	return($self->{db}->relativise($path, $name, $mountpoint, $self->{path}));
     }
-    die("DB::filename: unhandled case\n"); #FIXME
+    # should never happen
+    return "ERROR";
 }
 
 sub tags_subselect
 {
     my($self)=@_;
-    my $hasvals=$self->tag_has_values();
-    # we need to specially handle a bare /NOT/tag with no other clauses,
-    # using a simple WHERE id !='tagid' instead of a LEFT JOIN
-    if($self->{bare_not})
-    {
-	return $self->bare_not_subselect();
-    }
-    if($self->{in_all})
-    {
-	return "\tSELECT id FROM files AS files_id\n";
-    }
     my $tree=$self->{tagtree};
-    my $parent=$self->trailing_tag_parent();
-
-#    print "ELEMENTS: ", join('/', map { $_->{name}; } @{$self->{elements}}), "\n";
-#    print "TREE: ", $tree->print(), "\n";
-    my $tag=undef;
-    if($hasvals)
-    {
-	$tag=$self->trailing_tag_id();
-#	print "Trailing id: $tag\n";
-    }
-    my ($sqlclause, @joins)=(undef, ());
-    ($sqlclause, @joins) = $tree->to_sql($hasvals) if($tree);
-#    print "SQL(" . scalar(@joins) .": $sqlclause\n";
+#    use Data::Dumper;
+#    print Dumper $tree;
+    my ($sqlclause, @joins)=$tree->to_sql() if($tree);
     my $sql="\tSELECT fxt1.files_id FROM tags t1";
     my @crosses=();
     my @inners=();
-#    $joinsneeded++ if($tag);
+    @joins=@{$self->{joins}};
     for(my $i=0; $i <= $#joins; $i++)
     {
 	my $cnt=$i+1;
@@ -807,178 +759,75 @@ sub tags_subselect
     $sql .= ("\n\t" . join(" ", @crosses)) if(@crosses);
     $sql .= ("\n" . join("\n", @inners)) if(@inners);
     $sql .= "\n\tWHERE $sqlclause" if($sqlclause);
-#    if($tag)
-#    {
-#	$sql .= " AND t${joinsneeded}.parents_id='$tag'";
-#    }
     $sql .= "\n\tGROUP BY fxt1.files_id\n";
     return $sql;
 }
 
-sub bare_not_subselect
+sub sql_start
 {
-    my($self)=@_;
-    my @tags=grep { ref($_) eq "ID3FS::PathElement::Tag"; } @{$self->{elements}};
-    my $sql=("\tSELECT f1.id AS files_id FROM files f1 WHERE f1.id NOT IN (\n" .
-	     "\t\tSELECT fxt1.files_id FROM tags t1\n" .
-	     "\t\tINNER JOIN files_x_tags fxt1 ON t1.id=fxt1.tags_id\n" .
-	     "\t\tWHERE ");
-    if(scalar(@tags) > 1)
+    my($self, $tables)=@_;
+    my $sql="SELECT $tables FROM ";
+    if($self->{in_all})
     {
-	$sql .= ("(t1.parents_id='" . $tags[0]->{id} . "' AND t1.id='" .
-		 $tags[1]->{id} . "')");
+	$sql .= "files\n";
     }
     else
     {
-	$sql .= ("(t1.parents_id='' AND t1.id='" . $tags[0]->{id} . "')");
-    }
-    $sql .= "\n\t\tGROUP BY fxt1.files_id\n\t)\n";
-    return($sql);
-}
-
-sub constraints_tag_list
-{
-    my($self, @constraints)=@_;
-    my $lasttag=undef;
-    my @tags=();
-    my @tags_vals=();
-    for my $constraint (@constraints)
-    {
-#	print ref($constraint), ": ", $constraint->{name}, "\n";
-	if(ref($constraint) eq "ID3FS::PathElement::Tag")
-	{
-	    if(defined($lasttag))
-	    {
-#		print "TAGVAL\n";
-		push(@tags_vals, [$lasttag, $constraint->{id}]) if defined($constraint->{id});
-		$lasttag=undef;
-	    }
-	    elsif($self->tag_has_values($constraint->{id}))
-	    {
-#		print "HASVALUES\n";
-		$lasttag=$constraint->{id} if defined($constraint->{id});
-	    }
-	    else
-	    {
-#		print "NOVALUES\n";
-		push(@tags, $constraint->{id}) if(defined($constraint->{id}));
-	    }
-	}
-    }
-    unless($self->{db}->{postgres})
-    {
-	@tags=map{ "\"$_\""; } @tags;
-	@tags_vals=map( { [ map({ "\"$_\""; } @$_ ) ] } @tags_vals);
-	$lasttag="\"$lasttag\"" if defined($lasttag);
-    }
-    return(\@tags, \@tags_vals, $lasttag);
-}
-
-
-sub bare_tags
-{
-    my($self)=@_;
-    my $sql=("SELECT tags.name FROM tags\n" .
-	     "WHERE tags.parents_id=''\n" .
-	     "GROUP BY tags.name\n");
-    my @names=$self->{db}->cmd_firstcol($sql);
-    return (@names);
-}
-
-sub tags_with_values
-{
-    # FIXME: only shows one level of tag depth
-    my($self)=@_;
-    my $sql=("SELECT p.name, t.name  FROM tags t\n" .
-	     "INNER JOIN tags p ON t.parents_id=p.id\n" .
-	     "GROUP BY p.name, t.name\n");
-#    print "SQL: $sql\n";
-    my $result=$self->{db}->cmd_rows($sql);
-    my $tags={};
-    for my $pair (@$result)
-    {
-	push(@{$tags->{$pair->[0]}}, $pair->[1]);
+	$sql .= ("(\n" .
+		 $self->tags_subselect() .
+		 ") AS subselect\n" .
+		 "INNER JOIN files ON subselect.files_id=files.id\n");
     }
-    return $tags;
+    return $sql;
 }
 
-
+# we just filter $ALLTRACKS, $NOARTIST and $NOALBUM
+# filtering tags properly requires up to four levels of recursion
+# (tag/tagval/AND/NOT) and is too slow
 sub filter
 {
     my($self, @dirs)=@_;
+    return(@dirs) unless($ENABLE_FILTER);
     my $base=$self->{path};
     my @outdirs=();
-    # depth 4 to allow for tag/tagval/AND/NOT
-    my $maxdepth=4;
     for my $dir (@dirs)
     {
-#	print "\nFILTER (",$self->state(), "): $base / $dir\n";
-	if($self->empty("$base/$dir", $maxdepth))
-	{
-#	    print "empty: $base / $dir\n";
-	}
-	else
-	{
-#	    print "non-empty, accepting: $base / $dir\n";
-	    push(@outdirs, $dir);
-	}
+	push(@outdirs, $dir) unless($self->empty("$base/$dir"));
     }
     return(@outdirs);
 }
 
 sub empty
 {
-    my($self, $dir, $maxdepth)=@_;
-    return 0 unless($maxdepth);
-#    print "testing($maxdepth): $dir\n";
-    my $path=ID3FS::Path->new($self->{db}, $dir, $self->{verbose});
-#    print "PATH INVALID\n" unless($path->isvalid());
+    my($self, $dir)=@_;
+    my $path=ID3FS::Path->new($self->{db}, $dir, $self->{verbose},
+			      ($self->{maxtagdepth} - $self->{curtagdepth}));
     return 1 unless($path->isvalid());
     my($subdirs,$subfiles)=$path->dirents();
-#    print "SUBDENTS: ", join(", ", @$subdirs, @$subfiles), "\n";
-#    print("SUBFILES: ", join(', ', @$subfiles), "\n") if(@$subfiles);
-    return 0 if(@$subfiles);
-    for my $subdir (@$subdirs)
-    {
-#	print "SUBSUB $dir/$subdir\n";
-	if(1) #$self->dir_is_special($subdir))
-	{
-	    if($self->empty("$dir/$subdir", ($maxdepth-1)))
-	    {
-#		print "EMPTY: $dir / $subdir\n";
-	    }
-	    else
-	    {
-#		print "NONEMPTY: $dir / $subdir\n";
-		return 0;
-	    }
-	}
-	else
-	{
-	    return 0;
-	}
-#	return 0 if($self->nonempty("$dir/$subdir", ($maxdepth-1)));
-    }
+    return 0 if(@$subfiles || @$subdirs);
     return 1;
 }
 
-sub tagname_has_values
-{
-    my($self, $name)=@_;
-    my $id=$self->{db}->lookup_id("tags", $name);
-    return 0 unless($id);
-    return $self->{db}->tag_has_values($id);
-
-}
-
-sub dir_is_special
+# if path is .../OR/ or .../OR/NOT or .../AND/NOT
+sub want_all_tags
 {
-    my($self, $dir)=@_;
-    if((grep { $_ eq $dir; }
-	qw(AND OR NOT), $PATH_ALLTRACKS, $PATH_NOARTIST, $PATH_NOALBUM) ||
-       ($self->tagname_has_values($dir)))
+    my($self)=@_;
+    my $tail=$self->tail();
+    return 0 unless($tail);
+    my $parent=$self->tail_parent();
+    my $parent_valid = ($parent && $parent->type() == $TYPE_BOOL);
+    if($tail->type() == $TYPE_BOOL)
+    {
+	return 1 if($tail->name() eq "OR");
+	return 0 unless($tail->name() eq "NOT");
+	return 0 unless($parent_valid);
+	return 1 if($parent->name() eq "OR");
+	return 1 if($parent->name() eq "AND");
+    }
+    elsif($tail->type() == $TYPE_TAG)
     {
-	return 1;
+	return 0 unless($parent_valid);
+	return 1 if($parent->name() eq "NOT");
     }
     return 0;
 }