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package DTL::Fast::Expression::Operator::Binary::In;
use strict;
use utf8;
use warnings FATAL => 'all';
use parent 'DTL::Fast::Expression::Operator::Binary';

$DTL::Fast::OPS_HANDLERS{in} = __PACKAGE__;

use DTL::Fast::Expression::Operator::Binary::Eq;

sub dispatch
{
    my ( $self, $arg1, $arg2, $context) = @_;
    my ($arg1_type, $arg2_type) = (ref $arg1, ref $arg2);
    my $result = undef;

    if (not $arg2_type and not $arg1_type) # substring checking
    {
        $result = index($arg2, $arg1) > - 1 ? 1 : 0;
    }
    elsif (not $arg1_type and $arg2_type eq 'ARRAY')  # operand in array
    {
        $result = 0;
        foreach my $a2 (@$arg2)
        {
            # @todo: deep comparision, shouldn't it be optional?
            if (DTL::Fast::Expression::Operator::Binary::Eq::dispatch($self, $arg1, $a2))
            {
                $result = 1;
                last;
            }
        }
    }
    elsif (not $arg1_type and $arg2_type eq 'HASH')  # exists synonim
    {
        $result = exists $arg2->{$arg1} ? 1 : 0;
    }
    elsif ($arg2_type eq 'ARRAY' and $arg1_type eq 'ARRAY')  # second operand is an ARRAY
    {
        $result = 1;
        foreach my $a1 (@$arg1)
        {
            my $found = 0;
            foreach my $a2 (@$arg2)
            {
                # @todo: deep comparision, shouldn't it be optional?
                if (DTL::Fast::Expression::Operator::Binary::Eq::dispatch($self, $a1, $a2))
                {
                    $found = 1;
                    last;
                }
            }

            if (not $found)
            {
                $result = 0;
                last;
            }
        }
    }
    elsif ($arg2_type eq 'HASH' and $arg1_type eq 'HASH')   # hash contains hash
    {
        $result = 1;
        foreach my $key1 (keys %$arg1)
        {
            if (
                not exists $arg2->{$key1}
                    # @todo: deep comparision, shouldn't it be optional?
                    or not DTL::Fast::Expression::Operator::Binary::Eq::dispatch($self, $arg1->{$key1}, $arg2->{$key1})
            )
            {
                $result = 0;
                last;
            }
        }
    }

    # `in` method implementation
    if (
        not defined $result
            and UNIVERSAL::can($arg1, 'in')
    )
    {
        $result = $arg1->in($arg2);
    }

    # `contains` method implementation
    if (
        not defined $result
            and UNIVERSAL::can($arg2, 'contains')
    )
    {
        $result = $arg2->contains($arg1);
    }

    # still nothing
    if (not defined $result)
    {
        die $self->get_render_error(
                $context,
                sprintf("Don't know how to check that %s (%s) is in %s (%s)"
                    , $arg1 // 'undef'
                    , $arg1_type || 'SCALAR'
                    , $arg2 // 'undef'
                    , $arg2_type || 'SCALAR'
                )
            );
    }

    return $result;
}

1;