File Coverage

blib/lib/Template/Resolver.pm

Criterion	Covered	Total	%
statement	100	108	92.5
branch	27	42	64.2
condition	14	23	60.8
subroutine	17	17	100.0
pod	2	2	100.0
total	160	192	83.3

use strict;
use warnings;

package Template::Resolver;
$Template::Resolver::VERSION = '1.16';
# ABSTRACT: A powerful, and simple, library for resolving placeholders in templated files
# PODNAME: Template::Resolver

use Carp;
use Log::Any;
use Scalar::Util qw(blessed);
use Template::Transformer;

my $logger = Log::Any->get_logger();

sub new {
    return bless( {}, shift )->_init(@_);
}

sub _entity_to_properties {
    my ( $entity, $properties, $prefix ) = @_;

    $properties = {} unless $properties;

    my $ref = ref($entity);
    if ( ( $ref && $ref eq 'HASH' ) || blessed($entity) ) {
        foreach my $key ( keys( %{$entity} ) ) {
            _entity_to_properties( $entity->{$key}, $properties,
                ( $prefix ? "$prefix.$key" : $key ) );
        }
    }
    elsif ( $ref && $ref eq 'ARRAY' ) {
        my $index = 0;
        foreach my $array_entity ( @{$entity} ) {
            _entity_to_properties( $array_entity, $properties,
                ( $prefix ? "$prefix\[$index\]" : "[$index]" ) );
            $index++;
        }
    }
    elsif ($ref) {
        croak("unsupported ref type '$ref'");
    }
    else {
        $properties->{$prefix} = $entity;
    }

    return $properties;
}

sub _get_property {
    my ( $self, $value, $transform ) = @_;
    my $transformed = $self->{transformer}->transform( $value, $transform );
    croak( "undefined value $value" . ( $transform ? ", using transform $transform" : '' ) )
        unless ( defined($transformed) );
    return $transformed;
}

sub _init {
    my ( $self, $entity, %options ) = @_;

    my $os = $options{os} || $^O;

    $logger->debug('creating new Resolver');

    $self->{entity}      = $entity;
    $self->{transformer} = Template::Transformer->new(
        $os,
        _entity_to_properties($entity),
        (   $options{additional_transforms}
            ? ( additional_transforms => $options{additional_transforms} )
            : ()
        )
    );

    return $self;
}

sub _resolve_loop {
    my ( $self, $template_key, $loop_name, $property_name, $content ) = @_;
    my $property_value = $self->_get_value($property_name);
    my $result         = '';
    my $ref            = ref($property_value);
    my ( $replacer, $key_match, @keys );

    if ( $ref && $ref eq 'HASH' ) {
        $replacer  = sub { return $_[1] ? $_[0] : "${property_name}.${_[0]}" };
        $key_match = "key";
        @keys      = sort( keys(%$property_value) );
    }
    elsif ( $ref && $ref eq 'ARRAY' ) {
        $replacer  = sub { return $_[1] ? $_[0] : "${property_name}[${_[0]}]" };
        $key_match = "ix";
        @keys      = keys(@$property_value);
    }
    elsif ($ref) {
        croak("'$property_name': cannot loop on unsupported ref type '$ref'");
    }
    else {
        croak("'$property_name': does not exist");
    }

    my $resolve_template = sub {
        my ( $text, $key ) = @_;
        if ( $text eq "\$\{\Q$template_key\E<\Q$loop_name\E\.\Q$key_match\E\}\}" ) {
            $text = $key;
        }
        else {
            $text =~ s/<\Q$loop_name\E(\.\Q$key_match\E)?>/$replacer->($key,$1)/egs;
        }
        return $text;
    };

    foreach my $key (@keys) {
        my $line = $content;
        $line =~ s/\$\{$template_key<\Q$loop_name\E\.\Q$key_match\E>\}/$key/egs;
        $line =~ s/(\$\{$template_key.*?\}\})/$resolve_template->($1, $key)/egs;
        $result = $result . $line;
    }

    return $result;
}

sub _resolve_loops {
    my ( $self, $key, $content ) = @_;
    my $done = 0;
    while ( !$done ) {
        my $converted = $content
            =~ s/\$\{$key<(\S+)>:\{(.*?)\}\}(.*?)\$\{$key<\1>:end\}/$self->_resolve_loop($key,$1,$2,$3)/egs;
        $done = ( $converted == 0 );
    }
    return $content;
}

sub _get_value {
    my ( $self, $key ) = @_;
    my $val = $self->{entity};
    for my $token ( split( /\./, $key ) ) {
        my ( $name, $indices ) = $token =~ /^(\w+)?((?:\[\d+\])*)$/;
        croak("Invalid entity: '$key'") if ( !$name && !$indices );
        $val = $val->{$name} if ($name);
        if ($indices) {
            for my $index ( split( /\]\[/, substr( $indices, 1, length($indices) - 2 ) ) ) {
                $val = $val->[$index];
            }
        }
    }
    return $val;
}

sub resolve {
    my ( $self, %options ) = @_;

    my $key = $options{key} || 'TEMPLATE';

    my $content;
    if ( $options{content} ) {
        $content = $options{content};
    }
    elsif ( $options{handle} ) {
        $content = do { local ($/) = undef; <$options{handle}> };
    }
    elsif ( $options{filename} ) {
        $content = do { local ( @ARGV, $/ ) = $options{filename}; <> };
    }
    else {
        croak('Must provide one of [content, handle, filename]');
    }
    $content = $self->_resolve_loops( $key, $content );
    $content =~ s/\$\{$key(?:_(.*?))?\{(.*?)\}\}/$self->_get_property($2,$1)/egs;
    return $content;
}

1;

__END__