package App::DuckPAN::TemplateDefinitions;
our $AUTHORITY = 'cpan:DDG';
# ABSTRACT: Parse the template definitions file to create templates and template sets
$App::DuckPAN::TemplateDefinitions::VERSION = '1019';
use Moo;

use Try::Tiny;
use Path::Tiny;
use YAML::XS qw(LoadFile);

use App::DuckPAN::Template;
use App::DuckPAN::TemplateSet;

use namespace::clean;

has templates_yml => (
	is       => 'ro',
	required => 1,
	default  => sub { path('template', 'templates.yml') },
	doc      => 'Path to the YAML file with template definitions',
);

has _templates_data => (
	is       => 'rwp',
	init_arg => undef,
	doc      => 'Raw template definitions read from the template definitions file',
);

has _template_map => (
	is       => 'ro',
	lazy     => 1,
	builder  => 1,
	init_arg => undef,
	doc      => 'Hashref of tempate name => App::DuckPAN::Template instances ' .
	            'built from the templates_yml file',
);

sub _build__template_map {
	my $self = shift;
	my $template_root = path($self->templates_yml)->parent;
	my $data = $self->_templates_data->{templates};
	my %template_map;

	for my $name (keys %$data) {
	    my $template_data = $data->{$name};

	    my $template = App::DuckPAN::Template->new(
	        name          => $name,
	        label         => $template_data->{label},
	        input_file    => path($template_root, $template_data->{input}),
	        output_file   => path($template_data->{output}),
	    );

	    $template_map{$name} = $template;
	}

	return \%template_map;
}

has _template_sets => (
	is      => 'ro',
	builder => 1,
	lazy    => 1,
	doc     => 'hashref of template set name to App::DuckPAN::TemplateSet instances ' .
	           'built from the templates_yml file',
);

sub _build__template_sets {
	my $self = shift;
	my $sets_data = $self->_templates_data->{template_sets};
	my %template_sets;

	for my $name (keys %$sets_data) {
	    my $data     = $sets_data->{$name};
	    my @required = @{$data->{required} // []};
	    my @optional = @{$data->{optional} // []};
	    my $subdir_support = $data->{subdir_support};

	    # check if all templates in this set are defined
	    for my $template_name (@required, @optional) {
	        die "Template '$template_name' not defined in " . $self->templates_yml
	            unless $self->_template_map->{$template_name};
	    }

	    my $template_set = App::DuckPAN::TemplateSet->new(
	        name               => $name,
	        description        => $data->{description},
	        required_templates => [ @{$self->_template_map}{@required} ],
	        optional_templates => [ @{$self->_template_map}{@optional} ],
	        defined($subdir_support) ? (subdir_support => $subdir_support) : (),
	    );

	    $template_sets{$name} = $template_set;
	}

	return \%template_sets;
}

# Get a template set by name
sub get_template_set {
	my ($self, $name) = @_;

	return $self->_template_sets->{$name};
}

# Get all available template set names
sub get_template_sets {
	my ($self) = @_;

	return values %{$self->_template_sets};
}

# Get a list of all templates
sub get_templates {
	my ($self) = @_;

	return values %{$self->_template_map};
}

sub BUILD {
	my $self = shift;

	try {
	    $self->_set__templates_data(LoadFile($self->templates_yml));
	} catch {
	    die "Error loading template definitions file " . $self->templates_yml . ": $_";
	};
}

1;

__END__

=pod

=head1 NAME

App::DuckPAN::TemplateDefinitions - Parse the template definitions file to create templates and template sets

=head1 VERSION

version 1019

=head1 AUTHOR

DuckDuckGo <open@duckduckgo.com>, Zach Thompson <zach@duckduckgo.com>, Zaahir Moolla <moollaza@duckduckgo.com>, Torsten Raudssus <torsten@raudss.us> L<https://raudss.us/>

=head1 COPYRIGHT AND LICENSE

This software is Copyright (c) 2013 by DuckDuckGo, Inc. L<https://duckduckgo.com/>.

This is free software, licensed under:

  The Apache License, Version 2.0, January 2004

=cut