better indentation and interpolation

[scpubgit/Q-Branch.git] / lib / SQL / Abstract / Formatter.pm

diff --git a/lib/SQL/Abstract/Formatter.pm b/lib/SQL/Abstract/Formatter.pm
index b3c70ed..6fedeb5 100644 (file)
--- a/lib/SQL/Abstract/Formatter.pm
+++ b/lib/SQL/Abstract/Formatter.pm
@@ -9,16 +9,60 @@ has max_width => (is => 'ro', default => 78);
 
 sub _join {
   shift;
-  SQL::Abstract::Parts::stringify(\@_);
+  return SQL::Abstract::Parts::stringify(\@_);
 }
 
 sub format {
   my ($self, $join, @parts) = @_;
-::Dwarn [ J => $join => @parts ];
-  my $sql = $self->_join($join, @parts);
-  return $sql unless length($sql) > $self->max_width;
-  local $self->{max_width} = $self->{max_width} - length($self->indent_by);
-  return join("\n", map $self->format(@$_), @parts);
+  $self->_fold_sql('', '', @{$self->_simplify($join, @parts)});
+}
+
+sub _simplify {
+  my ($self, $join, @parts) = @_;
+  return '' unless @parts;
+  return $parts[0] if @parts == 1 and !ref($parts[0]);
+  return $self->_simplify(@{$parts[0]}) if @parts == 1;
+  return [ $join, map ref() ? $self->_simplify(@$_) : $_, @parts ];
+}
+
+sub _fold_sql {
+  my ($self, $indent0, $indent, $join, @parts) = @_;
+  my @res;
+  my $w = $self->max_width;
+  my $join_len = 0;
+  (s/, \Z/,\n/ and $join_len = 1)
+    or s/\A /\n/
+    or $_ = "\n"
+      for my $line_join = $join;
+  my ($nl_pre, $nl_post) = split "\n", $line_join;
+  my $line = $indent0;
+  my $next_indent = $indent.$self->indent_by;
+  PART: foreach my $idx (0..$#parts) {
+    my $p = $parts[$idx];
+    my $pre = $idx ? $join : '';
+    my $j_part = $pre.(my $j = ref($p) ? $self->_join(@$p) : $p);
+    if (length($j_part) + length($line) + $join_len <= $w) {
+      $line .= $j_part;
+    } else {
+      if (ref($p) and $p->[1] eq '(' and $p->[-1] eq ')') {
+        push @res, $line.($line =~ /S/ ? $join : '').'('."\n";
+        my (undef, undef, $inner) = @$p;
+        my $folded = $self->_fold_sql($indent, $indent, @$inner);
+        push @res, $folded."\n";
+        $line = $indent0.')'.($nl_post and $idx < $#parts ? ' '.$nl_post : '');
+        next PART;
+      }
+      push @res, $line.$nl_pre."\n" if $line =~ /\S/;
+      if (length($line = $indent.$nl_post.$j) <= $w) {
+        next PART;
+      }
+      my $folded = $self->_fold_sql($indent.$nl_post, $next_indent, @$p);
+      $folded =~ s/\n\Z//;
+      push @res, $folded.$nl_pre."\n";
+      $line = $idx == $#parts ? '' : $indent.$nl_post;
+    }
+  }
+  return join '', @res, $line;
 }
 
 1;