package cf::pod;

use Pod::POM;

our $indent;
our $level;
our @result;

package cf::pod::AsParagraphs;

use strict;

use base "Pod::POM::View";

my %E = (
   "<" => "E<lt>",
   ">" => "E<gt>",
);

sub aspod($) {
   local $_ = $_[0];

   s/[<>]/$E{$1}/g;

   $_
}

sub flatten($) {
   local $_ = $_[0];

   s/^\s+//;
   s/\s+$//;
   s/\s+/ /g;

   $_
}

*view_seq_file   = sub { "B<$_[1]>" };
*view_seq_code   = sub { "B<$_[1]>" };
*view_seq_bold   = sub { "B<$_[1]>" };
*view_seq_italic = sub { "I<$_[1]>" };
*view_seq_zero   = sub { "Z<>" };
*view_seq_space  = sub { my $text = $_[1]; $text =~ s/ /\xa0/g; $text };
*view_seq_index  = sub { push @{ $result[-1]{index} }, $_[1]; "" };

sub view_seq_text {
   my $text = $_[1];
   $text =~ s/\s+/ /g;
   aspod $text
}

sub view_seq_link {
   my (undef, $link) = @_;

   my $text = $link =~ s/^(.*)\|// ? $1 : $link;

   if ($link =~ /http:/) {
      "U<" . (aspod $link) . ">"
   } else {
      ()
   }
}

sub view_item {
   push @result, {
      type   => "item",
      indent => $indent * 8,
      level  => $level,
   };
   my $title = $_[1]->title->present ($_[0]);
   $result[-1]{markup} = $title if length $title;
   $title = flatten $title; unshift @{ $result[-1]{index} }, $title if length $title;
   local $level = $level + 1;
   $_[1]->content->present ($_[0]);
   ()
}

sub view_verbatim {
   push @result, {
      type   => "verbatim",
      indent => $indent * 16,
      level  => $level,
      markup => $_[1],
   };
   ()
}

sub view_textblock {
   push @result, {
      indent => $indent * 16,
      level  => $level,
      markup => flatten $_[1],
   };
   ()
}

sub view_head1 {
   push @result, {
      type   => "head1",
      indent => $indent * 16,
      level  => $level,
   };
   my $title = $_[1]->title->present ($_[0]);
   $result[-1]{markup} = $title if length $title;
   $title = flatten $title; unshift @{ $result[-1]{index} }, $title if length $title;
   local $level = $level + 1;
   $_[1]->content->present ($_[0]);
   ()
};

sub view_head2 {
   push @result, {
      type   => "head2",
      indent => $indent * 16,
      level  => $level,
   };
   my $title = $_[1]->title->present ($_[0]);
   $result[-1]{markup} = $title if length $title;
   $title = flatten $title; unshift @{ $result[-1]{index} }, $title if length $title;
   local $level = $level + 1;
   $_[1]->content->present ($_[0]);
   ()
};

sub view_head3 {
   push @result, {
      type   => "head3",
      indent => $indent * 16,
      level  => $level,
   };
   my $title = $_[1]->title->present ($_[0]);
   $result[-1]{markup} = $title if length $title;
   $title = flatten $title; unshift @{ $result[-1]{index} }, $title if length $title;
   local $level = $level + 1;
   $_[1]->content->present ($_[0]);
   ()
};

sub view_over {
   local $indent = $indent + $_[1]->indent;
   push @result, { indent => $indent };
   $_[1]->content->present ($_[0]);
   ()
}

sub view_for {
   if ($_[1]->format eq "image") {
#      push @result, {
#         indent => $indent * 16,
#         level  => $level,
#         markup => (::special image => "pod/" . $_->text),
#      };
   }
   ()
}

sub view_begin {
   ()
}

sub view {
   my ($self, $type, $item) = @_;

   $item->content->present ($self);
}

#############################################################################

package cf::pod;

sub pom_as_paragraphs($) {
   my ($pom) = @_;

   # we suckers use global variables, unfortunately.
   my $guard = cf::lock_acquire "cf::pod::as_paragraphs";

   local $indent = 0;
   local $level  = 1;
   local @result = ( { } );

   $pom->present ("cf::pod::AsParagraphs");

   [grep $_->{index} || exists $_->{markup}, @result]
}

sub load_pod($) {
   my ($path) = @_;

   Coro::Storable::thaw cf::cache "cf::pod::as_paragraphs/$path" => [$path],
      5 => sub {
         my ($src) = @_;

         cf::fork_call {
            my $pod = $src->[0];
            utf8::decode $pod;
            Coro::Storable::blocking_nfreeze pom_as_paragraphs +(Pod::POM->new->parse_text ($pod))
         }
      };
}

# format as cfpod-style text
sub as_cfpod($) {
   my ($pars) = @_;

   my $res;

   for my $par (@$pars) {
      if ($par->{type} =~ /^head\d+$/) {
         $res .= "B<$par->{markup}>\n\n";
      } elsif ($par->{type} eq "verbatim") {
         $res .= "\n$par->{markup}\n\n";
      } elsif ($par->{type} eq "item") {
         $res .= "\n* I<$par->{markup}>\n\n";
      } else {
         $res .= "$par->{markup}\n\n";
      }
   }

   $res
}

1;