package Dancer2::Core::Role::Serializer;
# ABSTRACT: Role for Serializer engines
$Dancer2::Core::Role::Serializer::VERSION = '0.140001';
use Dancer2::Core::Types;
use Moo::Role;

with 'Dancer2::Core::Role::Engine';

sub supported_hooks {
    qw(
      engine.serializer.before
      engine.serializer.after
    );
}

sub _build_type {'Serializer'}

requires 'serialize';
requires 'deserialize';
requires 'loaded';

has error => (
    is        => 'rw',
    isa       => Str,
    predicate => 1,
);

around serialize => sub {
    my ( $orig, $self, $content, $options ) = @_;

    $self->execute_hook( 'engine.serializer.before', $content );
    my $serialized = eval {$self->$orig($content, $options);};

    if ($@) {
        $self->error($@);
    }else{
        $self->execute_hook( 'engine.serializer.after', $serialized );
    }
    return $serialized;
};

around deserialize => sub {
    my ( $orig, $self, $content, $options ) = @_;
    my $data = eval { $self->$orig($content, $options); };
    $self->error($@) if $@;
    return $data;
};

# attribute vs method?
has content_type => (
    is       => 'ro',
    isa      => Str,
    required => 1,
);

# most serializer don't have to overload this one
sub support_content_type {
    my ( $self, $ct ) = @_;
    return unless $ct;

    my @toks = split ';', $ct;
    $ct = lc( $toks[0] );
    return $ct eq $self->content_type;
}

1;

__END__

=pod

=head1 NAME

Dancer2::Core::Role::Serializer - Role for Serializer engines

=head1 VERSION

version 0.140001

=head1 DESCRIPTION

Any class that consumes this role will be able to be used as a
serializer under Dancer2.

In order to implement this role, the consumer B<must> implement the
methods C<serialize>, C<deserialize> and C<loaded>, and should define
the C<content_type> attribute value.

=head1 ATTRIBUTES

=head2 error

The error string in case the serializer is in error state.

=head2 content_type

The I<content type> of the object after being serialized. For example,
a JSON serializer would have a I<application/json> content type
defined.

=head1 METHODS

=head2 has_error

A predicate to check whether the serializer is in error state.

=head2 serialize($content, [\%options])

The serialize method need to be implemented by the consumer. It
receives the serializer class object and a reference to the object to
be serialized. Should return the object after being serialized, in the
content type defined by the C<content_type> attribute.

A third optional argument is a hash reference of options to the
serializer.

The serialize method must return bytes and therefore has to handle any
encoding.

=head2 deserialize($content, [\%options])

The inverse method of C<serialize>. Receives the serializer class
object and a string that should be deserialized. The method should
return a reference to the deserialized Perl data structure.

A third optional argument is a hash reference of options to the
serializer.

The deserialize method receives encoded bytes and must therefore
handle any decoding required.

=head2 loaded

This method should return a boolean true value if the serializer is
able to work. This method might verify the existence of some Perl
module or some other detail. If everything needed for the serializer
to work is present the method returns a true value. If not, returns a
false value.

=head1 METHODS

=head1 AUTHOR

Dancer Core Developers

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Alexis Sukrieh.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut