preprocess elements, calculating joins

[id3fs.git] / lib / ID3FS / Path.pm

diff --git a/lib/ID3FS/Path.pm b/lib/ID3FS/Path.pm
index c683101..855ea9e 100644 (file)
--- a/lib/ID3FS/Path.pm
+++ b/lib/ID3FS/Path.pm
@@ -356,11 +356,65 @@ sub parse
     {
        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);
 }
 
+sub number_joins
+{
+    my($self, @elements)=@_;
+    my @joins=qw(INNER);
+    my $table=1;
+    my $lastop=undef;
+    return () unless(@elements);
+    while(my $thing=shift @elements)
+    {
+       if($thing->type() == $TYPE_BOOL)
+       {
+           my $op=$thing->name();
+           if($op eq "AND")
+           {
+               $table++;
+               push(@joins, "INNER");
+           }
+           elsif($op eq "NOT")
+           {
+               unless($lastop && $lastop eq "AND")
+               {
+                   push(@joins, "LEFT");
+                   $table++;
+               }
+           }
+           elsif($op eq "OR")
+           {
+               if($lastop && $lastop eq "NOT")
+               {
+                   $table++;
+                   push(@joins, "INNER");
+               }
+           }
+           $lastop=$op;
+       }
+       else
+       {
+           # skip tags with values
+           if(@elements && $elements[0]->type() == $TYPE_TAG)
+           {
+               $thing=shift(@elements);
+           }
+           $thing->table($table);
+       }
+    }
+    return @joins;
+}
+
 sub state
 {
     my($self, $newstate)=@_;
@@ -670,12 +724,13 @@ sub tags_subselect
     my($self)=@_;
     my $hasvals=$self->expecting_values();
     my $tree=$self->{tagtree};
-    use Data::Dumper;
-    print Dumper $tree;
+#    use Data::Dumper;
+#    print Dumper $tree;
     my ($sqlclause, @joins)=$tree->to_sql($hasvals) if($tree);
     my $sql="\tSELECT fxt1.files_id FROM tags t1";
     my @crosses=();
     my @inners=();
+    @joins=@{$self->{joins}};
     for(my $i=0; $i <= $#joins; $i++)
     {
        my $cnt=$i+1;