# Copyright (C) 2012 Patrick "P. J." McDermott
#
# 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/>.

use strict;
use warnings;

use MarkdownBook::HTMLTree;
use HTML::TreeBuilder;

package MarkdownBook::Document;

sub new
{
	my ($class, $book, $file, $id, $title) = @_;
	my $self;

	$class = ref($class) || $class;
	$self = {};
	bless($self,$class);
	$self->{'book'} = $book;
	$self->{'file'} = $file;
	$self->{'id'} = $id;
	$self->{'title'} = $title;

	return $self;
}

sub book
{
	my ($self, $book) = @_;
	my $old = $self->{'book'};

	$self->{'book'} = $book if defined($book);

	return $old;
}

sub file
{
	my ($self, $file) = @_;
	my $old = $self->{'file'};

	$self->{'file'} = $file if defined($file);

	return $old;
}

sub file_path
{
	my ($self) = @_;

	return $self->{'book'}->dir() . '/' . $self->{'file'};
}

sub title
{
	my ($self, $title) = @_;
	my $old = $self->{'title'};

	$self->{'title'} = $title if defined($title);

	return $old;
}

sub prev
{
	my ($self, $other) = @_;
	my $old = $self->{'prev'};

	$self->{'prev'} = $other if defined($other);

	return $old;
}

sub next
{
	my ($self, $other) = @_;
	my $old = $self->{'next'};

	$self->{'next'} = $other if defined($other);

	return $old;
}

sub parse_html
{
	my ($self) = @_;
	my $file = $self->{'book'}->dir() . '/' . $self->{'file'} . '.html.in';

	$self->{'tree'} = HTML::TreeBuilder->new();
	$self->{'tree'}->parse_file($file);
}

sub number_sections
{
	my ($self) = @_;

	my @headers;
	my $header;
	my @secnums = (0, 0);
	my $curlev = -1;
	my $newlev;
	my $secstr;
	my @children;
	my $sectitle;
	my $secid;

	@{$self->{'tree_body'}} = MarkdownBook::HTMLTree::find_elements_by_tag_names(
		$self->{'tree'}, ('body'));
	@headers = MarkdownBook::HTMLTree::find_elements_by_tag_names(
		@{$self->{'tree_body'}}[0], ('h1', 'h2'));

	foreach $header (@headers) {

		# Calculate section number.
		$newlev = $header->tag();
		$newlev =~ s/^h(\d)$/$1/;
		if ($newlev != $curlev) {
			foreach (@secnums[$newlev .. $#secnums]) {
				$_ = 0;
			}
		}
		$curlev = $newlev;
		++$secnums[$newlev - 1];
		$secstr = join('.', @secnums);
		$secstr =~ s/(\.0)*$//;

		MarkdownBook::HTMLTree::each_text(sub {

				# Prefix section title with section number.
				my $sectitle = $_[1];
				$sectitle =~ s/^([^\[]+)[ ]*\[[^\]]+\]$/$_[2].$secstr $1/;

				# Set "id" attribute.
				if ($_[1] =~ m/^[^\[\]]*\[([^\]]+)\][^\[\]]*$/) {
					my $secid = $_[1];
					$secid =~ s/^[^\[\]]*\[([^\]]+)\][^\[\]]*$/$1/;
					${$_[0]}->attr('id', $secid);
				}

				# Set section title.
				$_[1] = $sectitle;

			}, $header, $self->{'id'});

	}
}

sub output
{
	my ($self) = @_;

	my $elem;
	my %opt_end_tags;
	my $out;

	# Don't omit any end tags.
	%opt_end_tags = map([$_ => 0], %HTML::Element::optionalEndTag);

	foreach $elem (@{$self->{'tree_body'}}[0]->content_list()) {
		# It's safe to assume (ref($elem) eq 'HTML::Element').
		$out .= $elem->as_HTML('<>&', '', \%opt_end_tags) . "\n";
	}

	return $out;
}

1;