package Types::Standard::ScalarRef;

use 5.006001;
use strict;
use warnings;

BEGIN {
	$Types::Standard::ScalarRef::AUTHORITY = 'cpan:TOBYINK';
	$Types::Standard::ScalarRef::VERSION   = '1.004002';
}

use Types::Standard ();
use Types::TypeTiny ();

sub _croak ($;@) { require Error::TypeTiny; goto \&Error::TypeTiny::croak }

no warnings;

sub __constraint_generator
{
	return Types::Standard::ScalarRef unless @_;
	
	my $param = shift;
	Types::TypeTiny::TypeTiny->check($param)
		or _croak("Parameter to ScalarRef[`a] expected to be a type constraint; got $param");
	
	return sub
	{
		my $ref = shift;
		$param->check($$ref) || return;
		return !!1;
	};
}

sub __inline_generator
{
	my $param = shift;
	return unless $param->can_be_inlined;
	return sub {
		my $v = $_[1];
		my $param_check = $param->inline_check("\${$v}");
		"(ref($v) eq 'SCALAR' or ref($v) eq 'REF') and $param_check";
	};
}

sub __deep_explanation
{
	my ($type, $value, $varname) = @_;
	my $param = $type->parameters->[0];
	
	for my $item ($$value)
	{
		next if $param->check($item);
		return [
			sprintf('"%s" constrains the referenced scalar value with "%s"', $type, $param),
			@{ $param->validate_explain($item, sprintf('${%s}', $varname)) },
		];
	}
	
	# This should never happen...
	return;  # uncoverable statement
}

sub __coercion_generator
{
	my ($parent, $child, $param) = @_;
	return unless $param->has_coercion;
	
	my $coercable_item = $param->coercion->_source_type_union;
	my $C = "Type::Coercion"->new(type_constraint => $child);
	
	if ($param->coercion->can_be_inlined and $coercable_item->can_be_inlined)
	{
		$C->add_type_coercions($parent => Types::Standard::Stringable {
			my @code;
			push @code, 'do { my ($orig, $return_orig, $new) = ($_, 0);';
			push @code,    'for ($$orig) {';
			push @code, sprintf('++$return_orig && last unless (%s);', $coercable_item->inline_check('$_'));
			push @code, sprintf('$new = (%s);', $param->coercion->inline_coercion('$_'));
			push @code,    '}';
			push @code,    '$return_orig ? $orig : \\$new';
			push @code, '}';
			"@code";
		});
	}
	else
	{
		$C->add_type_coercions(
			$parent => sub {
				my $value = @_ ? $_[0] : $_;
				my $new;
				for my $item ($$value)
				{
					return $value unless $coercable_item->check($item);
					$new = $param->coerce($item);
				}
				return \$new;
			},
		);
	}
	
	return $C;
}

1;

__END__

=pod

=encoding utf-8

=head1 NAME

Types::Standard::ScalarRef - internals for the Types::Standard ScalarRef type constraint

=head1 STATUS

This module is considered part of Type-Tiny's internals. It is not
covered by the
L<Type-Tiny stability policy|Type::Tiny::Manual::Policies/"STABILITY">.

=head1 DESCRIPTION

This file contains some of the guts for L<Types::Standard>.
It will be loaded on demand. You may ignore its presence.

=head1 BUGS

Please report any bugs to
L<http://rt.cpan.org/Dist/Display.html?Queue=Type-Tiny>.

=head1 SEE ALSO

L<Types::Standard>.

=head1 AUTHOR

Toby Inkster E<lt>tobyink@cpan.orgE<gt>.

=head1 COPYRIGHT AND LICENCE

This software is copyright (c) 2013-2014, 2017-2018 by Toby Inkster.

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

=head1 DISCLAIMER OF WARRANTIES

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

