package Perl::Analysis::Static::Analysis::Declaration::Variable;
{
  $Perl::Analysis::Static::Analysis::Declaration::Variable::VERSION = '0.004'; # TRIAL
}

# ABSTRACT: find all declarations of variables

use Moose;
use Carp;
use English qw( -no_match_vars );    # Avoids regex performance penalty

use Perl::Analysis::Static::Element::Declaration::Variable::Lexical;
use Perl::Analysis::Static::Element::Declaration::Variable::Local;
use Perl::Analysis::Static::Element::Declaration::Variable::Package;

extends 'Perl::Analysis::Static::Analysis';

has '_ppi_class' =>
  ( is => 'rw', isa => 'Str', default => 'PPI::Statement::Variable' );

sub _convert {
    my ( $self, $node ) = @_;

    # get significant children
    my @schildren = $node->schildren();

    # the first child is the keyword, for lexical
    # variables this has to be 'my', for package 'our';
    my $type = _detect_type( $schildren[0] );

    # maybe a warning here?
    return unless $type;

    my $class =
      'Perl::Analysis::Static::Element::Declaration::Variable::' . $type;

    # variable (or list of variables) is the second child
    my $variables = $schildren[1];

    # "my $foo"?
    if ( $variables->isa('PPI::Token::Symbol') ) {
        my $name = $variables->content;

        return $class->new(
            name     => $name,
            from     => $node->location->[0],
            to       => $node->location->[0],
            ppi_node => $node
        );
    }

    # no, not "my $foo", so check for "my ($foo, $bar)"
    # list of variables is found in a PPI::Structure::List
    @schildren = $node->schildren();
    my $list = $schildren[1];
    unless ( $list->isa('PPI::Structure::List') ) {
        App::Perlanalyst::die('PANIC: Expected PPI::Structure::List');
    }

    # variable names are of class PPI::Token::Symbol
    my $symbols = $list->find('PPI::Token::Symbol');
    return map {
        $class->new(
            name     => $_->content,
            from     => $_->location->[0],
            to       => $_->location->[0],
            ppi_node => $node
        );

    } @$symbols;
}

sub _detect_type {
    my ($keyword) = @_;
    return 'Lexical' if $keyword eq 'my';
    return 'Package' if $keyword eq 'our';
    return 'Local'   if $keyword eq 'local';

    return;
}


1;

__END__
=pod

=head1 NAME

Perl::Analysis::Static::Analysis::Declaration::Variable - find all declarations of variables

=head1 VERSION

version 0.004

=head1 DESCRIPTION

This analysis looks for variable declarations. It may create three
different kinds of elements:
L<Perl::Analysis::Static::Element::Declaration::Variable::Lexical>
for declaration of lexical variables,
L<Perl::Analysis::Static::Element::Declaration::Variable::Local>
for declaration of local variables,
L<Perl::Analysis::Static::Element::Declaration::Variable::>
for declaration of package variables.

=head1 AUTHOR

Gregor Goldbach <glauschwuffel@nomaden.org>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2011 by Gregor Goldbach.

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