package Koha::Object;

# Copyright ByWater Solutions 2014
# Copyright 2016 Koha Development Team
#
# This file is part of Koha.
#
# Koha is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# Koha is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Koha; if not, see <http://www.gnu.org/licenses>.

use Modern::Perl;

use Carp qw( croak );
use Mojo::JSON;
use Scalar::Util qw( blessed looks_like_number );
use Try::Tiny qw( catch try );
use List::MoreUtils qw( any );

use Koha::Database;
use Koha::Exceptions::Object;
use Koha::DateUtils qw( dt_from_string output_pref );
use Koha::Object::Message;

=head1 NAME

Koha::Object - Koha Object base class

=head1 SYNOPSIS

    use Koha::Object;
    my $object = Koha::Object->new({ property1 => $property1, property2 => $property2, etc... } );

=head1 DESCRIPTION

This class must always be subclassed.

=head1 API

=head2 Class Methods

=cut

=head3 Koha::Object->new();

my $object = Koha::Object->new();
my $object = Koha::Object->new($attributes);

Note that this cannot be used to retrieve record from the DB.

=cut

sub new {
    my ( $class, $attributes ) = @_;
    my $self = {};

    if ($attributes) {
        my $schema = Koha::Database->new->schema;

        # Remove the arguments which exist, are not defined but NOT NULL to use the default value
        my $columns_info = $schema->resultset( $class->_type )->result_source->columns_info;
        for my $column_name ( keys %$attributes ) {
            my $c_info = $columns_info->{$column_name};
            next if $c_info->{is_nullable};
            next if not exists $attributes->{$column_name} or defined $attributes->{$column_name};
            delete $attributes->{$column_name};
        }

        $self->{_result} =
          $schema->resultset( $class->_type() )->new($attributes);
    }

    $self->{_messages} = [];

    croak("No _type found! Koha::Object must be subclassed!")
      unless $class->_type();

    bless( $self, $class );

}

=head3 Koha::Object->_new_from_dbic();

my $object = Koha::Object->_new_from_dbic($dbic_row);

=cut

sub _new_from_dbic {
    my ( $class, $dbic_row ) = @_;
    my $self = {};

    # DBIC result row
    $self->{_result} = $dbic_row;

    croak("No _type found! Koha::Object must be subclassed!")
      unless $class->_type();

    croak( "DBIC result _type " . ref( $self->{_result} ) . " isn't of the _type " . $class->_type() )
      unless ref( $self->{_result} ) eq "Koha::Schema::Result::" . $class->_type();

    bless( $self, $class );

}

=head3 $object->store();

Saves the object in storage.
If the object is new, it will be created.
If the object previously existed, it will be updated.

Returns:
    $self  if the store was a success
    undef  if the store failed

=cut

sub store {
    my ($self) = @_;

    my $columns_info = $self->_result->result_source->columns_info;

    # Handle not null and default values for integers and dates
    foreach my $col ( keys %{$columns_info} ) {
        # Integers
        if (   _numeric_column_type( $columns_info->{$col}->{data_type} )
            or _decimal_column_type( $columns_info->{$col}->{data_type} )
        ) {
            # Has been passed but not a number, usually an empty string
            my $value = $self->_result()->get_column($col);
            if ( defined $value and not looks_like_number( $value ) ) {
                if ( $columns_info->{$col}->{is_nullable} ) {
                    # If nullable, default to null
                    $self->_result()->set_column($col => undef);
                } else {
                    # If cannot be null, get the default value
                    # What if cannot be null and does not have a default value? Possible?
                    $self->_result()->set_column($col => $columns_info->{$col}->{default_value});
                }
            }
        }
        elsif ( _date_or_datetime_column_type( $columns_info->{$col}->{data_type} ) ) {
            # Set to null if an empty string (or == 0 but should not happen)
            my $value = $self->_result()->get_column($col);
            if ( defined $value and not $value ) {
                if ( $columns_info->{$col}->{is_nullable} ) {
                    $self->_result()->set_column($col => undef);
                } else {
                    $self->_result()->set_column($col => $columns_info->{$col}->{default_value});
                }
            }
            elsif ( not defined $self->$col
                  && $columns_info->{$col}->{datetime_undef_if_invalid} )
              {
                  # timestamp
                  $self->_result()->set_column($col => $columns_info->{$col}->{default_value});
              }
        }
    }

    try {
        return $self->_result()->update_or_insert() ? $self : undef;
    }
    catch {
        # Catch problems and raise relevant exceptions
        if (ref($_) eq 'DBIx::Class::Exception') {
            warn $_->{msg};
            if ( $_->{msg} =~ /Cannot add or update a child row: a foreign key constraint fails/ ) {
                # FK constraints
                # FIXME: MySQL error, if we support more DB engines we should implement this for each
                if ( $_->{msg} =~ /FOREIGN KEY \(`(?<column>.*?)`\)/ ) {
                    Koha::Exceptions::Object::FKConstraint->throw(
                        error     => 'Broken FK constraint',
                        broken_fk => $+{column}
                    );
                }
            }
            elsif( $_->{msg} =~ /Duplicate entry '(.*?)' for key '(?<key>.*?)'/ ) {
                Koha::Exceptions::Object::DuplicateID->throw(
                    error => 'Duplicate ID',
                    duplicate_id => $+{key}
                );
            }
            elsif( $_->{msg} =~ /Incorrect (?<type>\w+) value: '(?<value>.*)' for column \W?(?<property>\S+)/ ) { # The optional \W in the regex might be a quote or backtick
                my $type = $+{type};
                my $value = $+{value};
                my $property = $+{property};
                $property =~ s/['`]//g;
                Koha::Exceptions::Object::BadValue->throw(
                    type     => $type,
                    value    => $value,
                    property => $property =~ /(\w+\.\w+)$/ ? $1 : $property, # results in table.column without quotes or backtics
                );
            }
        }
        # Catch-all for foreign key breakages. It will help find other use cases
        $_->rethrow();
    }
}

=head3 $object->update();

A shortcut for set + store in one call.

=cut

sub update {
    my ($self, $values) = @_;
    Koha::Exceptions::Object::NotInStorage->throw unless $self->in_storage;
    $self->set($values)->store();
}

=head3 $object->delete();

Removes the object from storage.

Returns:
    The item object if deletion was a success
    The DBIX::Class error if deletion failed

=cut

sub delete {
    my ($self) = @_;

    my $deleted = $self->_result()->delete;
    if ( ref $deleted ) {
        my $object_class  = Koha::Object::_get_object_class( $self->_result->result_class );
        $deleted = $object_class->_new_from_dbic($deleted);
    }
    return $deleted;
}

=head3 $object->set( $properties_hashref )

$object->set(
    {
        property1 => $property1,
        property2 => $property2,
        property3 => $propery3,
    }
);

Enables multiple properties to be set at once

Returns:
    1      if all properties were set.
    0      if one or more properties do not exist.
    undef  if all properties exist but a different error
           prevents one or more properties from being set.

If one or more of the properties do not exist,
no properties will be set.

=cut

sub set {
    my ( $self, $properties ) = @_;

    my @columns = @{$self->_columns()};

    foreach my $p ( keys %$properties ) {
        unless ( grep { $_ eq $p } @columns ) {
            Koha::Exceptions::Object::PropertyNotFound->throw( "No property $p for " . ref($self) );
        }
    }

    return $self->_result()->set_columns($properties) ? $self : undef;
}

=head3 $object->set_or_blank( $properties_hashref )

$object->set_or_blank(
    {
        property1 => $property1,
        property2 => $property2,
        property3 => $propery3,
    }
);

If not listed in $properties_hashref, the property will be set to the default
value defined at DB level, or nulled.

=cut


sub set_or_blank {
    my ( $self, $properties ) = @_;

    my $columns_info = $self->_result->result_source->columns_info;

    foreach my $col ( keys %{$columns_info} ) {

        next if exists $properties->{$col};

        if ( $columns_info->{$col}->{is_nullable} ) {
            $properties->{$col} = undef;
        } else {
            $properties->{$col} = $columns_info->{$col}->{default_value};
        }
    }

    return $self->set($properties);
}

=head3 $object->unblessed();

Returns an unblessed representation of object.

=cut

sub unblessed {
    my ($self) = @_;

    return { $self->_result->get_columns };
}

=head3 $object->get_from_storage;

=cut

sub get_from_storage {
    my ( $self, $attrs ) = @_;
    my $stored_object = $self->_result->get_from_storage($attrs);
    return unless $stored_object;
    my $object_class  = Koha::Object::_get_object_class( $self->_result->result_class );
    return $object_class->_new_from_dbic($stored_object);
}

=head3 $object->object_messages

    my @messages = @{ $object->object_messages };

Returns the (probably non-fatal) messages that were recorded on the object.

=cut

sub object_messages {
    my ( $self ) = @_;

    $self->{_messages} = []
        unless defined $self->{_messages};

    return $self->{_messages};
}

=head3 $object->add_message

    try {
        <some action that might fail>
    }
    catch {
        if ( <fatal condition> ) {
            Koha::Exception->throw...
        }

        # This is a non fatal error, notify the caller
        $self->add_message({ message => $error, type => 'error' });
    }
    return $self;

Adds a message.

=cut

sub add_message {
    my ( $self, $params ) = @_;

    push @{ $self->{_messages} }, Koha::Object::Message->new($params);

    return $self;
}

=head3 $object->TO_JSON

Returns an unblessed representation of the object, suitable for JSON output.

=cut

sub TO_JSON {

    my ($self) = @_;

    my $unblessed    = $self->unblessed;
    my $columns_info = Koha::Database->new->schema->resultset( $self->_type )
        ->result_source->{_columns};

    foreach my $col ( keys %{$columns_info} ) {

        if ( $columns_info->{$col}->{is_boolean} )
        {    # Handle booleans gracefully
            $unblessed->{$col}
                = ( $unblessed->{$col} )
                ? Mojo::JSON->true
                : Mojo::JSON->false;
        }
        elsif ( _numeric_column_type( $columns_info->{$col}->{data_type} )
            and looks_like_number( $unblessed->{$col} )
        ) {
            # TODO: Remove once the solution for
            # https://github.com/perl5-dbi/DBD-mysql/issues/212
            # is ported to whatever distro we support by that time
            # or we move to DBD::MariaDB
            $unblessed->{$col} += 0;
        }
        elsif ( _decimal_column_type( $columns_info->{$col}->{data_type} )
            and looks_like_number( $unblessed->{$col} )
        ) {
            # TODO: Remove once the solution for
            # https://github.com/perl5-dbi/DBD-mysql/issues/212
            # is ported to whatever distro we support by that time
            # or we move to DBD::MariaDB
            $unblessed->{$col} += 0.00;
        }
        elsif ( _datetime_column_type( $columns_info->{$col}->{data_type} ) ) {
            eval {
                return unless $unblessed->{$col};
                $unblessed->{$col} = output_pref({
                    dateformat => 'rfc3339',
                    dt         => dt_from_string($unblessed->{$col}, 'sql'),
                });
            };
        }
    }
    return $unblessed;
}

sub _date_or_datetime_column_type {
    my ($column_type) = @_;

    my @dt_types = (
        'timestamp',
        'date',
        'datetime'
    );

    return ( grep { $column_type eq $_ } @dt_types) ? 1 : 0;
}
sub _datetime_column_type {
    my ($column_type) = @_;

    my @dt_types = (
        'timestamp',
        'datetime'
    );

    return ( grep { $column_type eq $_ } @dt_types) ? 1 : 0;
}

sub _numeric_column_type {
    # TODO: Remove once the solution for
    # https://github.com/perl5-dbi/DBD-mysql/issues/212
    # is ported to whatever distro we support by that time
    # or we move to DBD::MariaDB
    my ($column_type) = @_;

    my @numeric_types = (
        'bigint',
        'integer',
        'int',
        'mediumint',
        'smallint',
        'tinyint',
    );

    return ( grep { $column_type eq $_ } @numeric_types) ? 1 : 0;
}

sub _decimal_column_type {
    # TODO: Remove once the solution for
    # https://github.com/perl5-dbi/DBD-mysql/issues/212
    # is ported to whatever distro we support by that time
    # or we move to DBD::MariaDB
    my ($column_type) = @_;

    my @decimal_types = (
        'decimal',
        'double precision',
        'float'
    );

    return ( grep { $column_type eq $_ } @decimal_types) ? 1 : 0;
}

=head3 prefetch_whitelist

    my $whitelist = $object->prefetch_whitelist()

Returns a hash of prefetchable subs and the type they return.

=cut

sub prefetch_whitelist {
    my ( $self ) = @_;

    my $whitelist = {};
    my $relations = $self->_result->result_source->_relationships;

    foreach my $key (keys %{$relations}) {
        if($self->can($key)) {
            my $result_class = $relations->{$key}->{class};
            my $obj = $result_class->new;
            try {
                $whitelist->{$key} = Koha::Object::_get_object_class( $obj->result_class );
            } catch {
                $whitelist->{$key} = undef;
            }
        }
    }

    return $whitelist;
}

=head3 to_api

    my $object_for_api = $object->to_api(
        {
          [ embed => {
                items => {
                    children => {
                        holds => {,
                            children => {
                              ...
                            }
                        }
                    }
                },
                library => {
                    ...
                }
            },
            public => 0|1,
            ...
         ]
        }
    );

Returns a representation of the object, suitable for API output.

=cut

sub to_api {
    my ( $self, $params ) = @_;

    my $json_object = $self->TO_JSON;

    # Make sure we duplicate the $params variable to avoid
    # breaking calls in a loop (Koha::Objects->to_api)
    $params = defined $params ? {%$params} : {};

    # children should be able to handle without
    my $embeds  = delete $params->{embed};
    my $strings = delete $params->{strings};

    # coded values handling
    my $string_map = {};
    if ( $strings and $self->can('strings_map') ) {
        $string_map = $self->strings_map($params);
    }

    # Remove forbidden attributes if required (including their coded values)
    if ( $params->{public} ) {
        for my $field ( keys %{$json_object} ) {
            delete $json_object->{$field}
              unless any { $_ eq $field } @{ $self->public_read_list };
        }

        if ($strings) {
            foreach my $field ( keys %{$string_map} ) {
                delete $string_map->{$field}
                  unless any { $_ eq $field } @{ $self->public_read_list };
            }
        }
    }

    # Remove forbidden attributes if required (including their coded values)
    if ( !$self->is_accessible($params) ) {
        for my $field ( keys %{$json_object} ) {
            unless ( any { $_ eq $field } @{ $self->unredact_list } ) {
                $json_object->{$field} = undef;
            }
        }

        if ($strings) {
            foreach my $field ( keys %{$string_map} ) {
                unless ( any { $_ eq $field } @{ $self->unredact_list } ) {
                    $string_map->{$field} = undef;
                }
            }
        }
    }

    my $to_api_mapping = $self->to_api_mapping;

    # Rename attributes and coded values if there's a mapping
    if ( $self->can('to_api_mapping') ) {
        foreach my $column ( keys %{ $self->to_api_mapping } ) {
            my $mapped_column = $self->to_api_mapping->{$column};
            if ( exists $json_object->{$column}
                && defined $mapped_column )
            {

                # key != undef
                $json_object->{$mapped_column} = delete $json_object->{$column};
                $string_map->{$mapped_column}  = delete $string_map->{$column}
                  if exists $string_map->{$column};

            }
            elsif ( exists $json_object->{$column}
                && !defined $mapped_column )
            {

                # key == undef
                delete $json_object->{$column};
                delete $string_map->{$column};
            }
        }
    }

    $json_object->{_strings} = $string_map
      if $strings;

    if ($embeds) {
        foreach my $embed ( keys %{$embeds} ) {
            if (    $embed =~ m/^(?<relation>.*)_count$/
                and $embeds->{$embed}->{is_count} )
            {

                my $relation = $+{relation};
                $json_object->{$embed} = $self->$relation->count;
            }
            else {
                my $curr = $embed;
                my $next = $embeds->{$curr}->{children};

                $params->{strings} = 1
                  if $embeds->{$embed}->{strings};

                my $children = $self->$curr;

                if ( defined $children and ref($children) eq 'ARRAY' ) {
                    my @list = map {
                        $self->_handle_to_api_child(
                            {
                                child  => $_,
                                next   => $next,
                                curr   => $curr,
                                params => $params
                            }
                        )
                    } @{$children};
                    $json_object->{$curr} = \@list;
                }
                else {
                    $json_object->{$curr} = $self->_handle_to_api_child(
                        {
                            child  => $children,
                            next   => $next,
                            curr   => $curr,
                            params => $params
                        }
                    );
                }
            }
        }
    }

    return $json_object;
}

=head3 to_api_mapping

    my $mapping = $object->to_api_mapping;

Generic method that returns the attribute name mappings required to
render the object on the API.

Note: this only returns an empty I<hashref>. Each class should have its
own mapping returned.

=cut

sub to_api_mapping {
    return {};
}

=head3 strings_map

    my $string_map = $object->strings_map($params);

Generic method that returns the string map for coded attributes.

Return should be a hashref keyed on database field name with the values
being hashrefs containing 'str', 'type' and optionally 'category'.

This is then used in to_api to render the _strings embed when requested.

Note: this only returns an empty I<hashref>. Each class should have its
own mapping returned.

=cut

sub strings_map {
    return {};
}

=head3 public_read_list


    my @public_read_list = @{$object->public_read_list};

Generic method that returns the list of database columns that are allowed to
be passed to render objects on the public API.

Note: this only returns an empty I<arrayref>. Each class should have its
own implementation.

=cut

sub public_read_list
 {
    return [];
}

=head3 unredact_list

    my @unredact_list = @{$object->unredact_list};

Generic method that returns the list of database columns that are allowed to
be passed to render objects on the API when the user making the request should
not ordinarily have unrestricted access to the data (as returned by the is_accesible method).

Note: this only returns an empty I<arrayref>. Each class should have its
own implementation.

=cut

sub unredact_list {
    return [];
}

=head3 from_api_mapping

    my $mapping = $object->from_api_mapping;

Generic method that returns the attribute name mappings so the data that
comes from the API is correctly renamed to match what is required for the DB.

=cut

sub from_api_mapping {
    my ( $self ) = @_;

    my $to_api_mapping = $self->to_api_mapping;

    unless ( defined $self->{_from_api_mapping} ) {
        $self->{_from_api_mapping} = {};
        while (my ($key, $value) = each %{ $to_api_mapping } ) {
            $self->{_from_api_mapping}->{$value} = $key
                if defined $value;
        }
    }

    return $self->{_from_api_mapping};
}

=head3 new_from_api

    my $object = Koha::Object->new_from_api;
    my $object = Koha::Object->new_from_api( $attrs );

Creates a new object, mapping the API attribute names to the ones on the DB schema.

=cut

sub new_from_api {
    my ( $class, $params ) = @_;

    my $self = $class->new;
    return $self->set_from_api( $params );
}

=head3 set_from_api

    my $object = Koha::Object->new(...);
    $object->set_from_api( $attrs )

Sets the object's attributes mapping API attribute names to the ones on the DB schema.

=cut

sub set_from_api {
    my ( $self, $from_api_params ) = @_;

    return $self->set( $self->attributes_from_api( $from_api_params ) );
}

=head3 attributes_from_api

    my $attributes = attributes_from_api( $params );

Returns the passed params, converted from API naming into the model.

=cut

sub attributes_from_api {
    my ( $self, $from_api_params ) = @_;

    my $from_api_mapping = $self->from_api_mapping;

    my $params;
    my $columns_info = $self->_result->result_source->columns_info;
    my $dtf          = $self->_result->result_source->storage->datetime_parser;

    while (my ($key, $value) = each %{ $from_api_params } ) {
        my $koha_field_name =
          exists $from_api_mapping->{$key}
          ? $from_api_mapping->{$key}
          : $key;

        if ( $columns_info->{$koha_field_name}->{is_boolean} ) {
            # TODO: Remove when D8 is formally deprecated
            # Handle booleans gracefully
            $value = ( $value ) ? 1 : 0;
        }
        elsif ( _date_or_datetime_column_type( $columns_info->{$koha_field_name}->{data_type} ) ) {
            try {
                if ( $columns_info->{$koha_field_name}->{data_type} eq 'date' ) {
                    $value = $dtf->format_date(dt_from_string($value, 'iso'))
                        if defined $value;
                }
                else {
                    $value = $dtf->format_datetime(dt_from_string($value, 'rfc3339'))
                        if defined $value;
                }
            }
            catch {
                Koha::Exceptions::BadParameter->throw( parameter => $key );
            };
        }

        $params->{$koha_field_name} = $value;
    }

    return $params;
}

=head3 $object->unblessed_all_relateds

my $everything_into_one_hashref = $object->unblessed_all_relateds

The unblessed method only retrieves column' values for the column of the object.
In a *few* cases we want to retrieve the information of all the prefetched data.

=cut

sub unblessed_all_relateds {
    my ($self) = @_;

    my %data;
    my $related_resultsets = $self->_result->{related_resultsets} || {};
    my $rs = $self->_result;
    while ( $related_resultsets and %$related_resultsets ) {
        my @relations = keys %{ $related_resultsets };
        if ( @relations ) {
            my $relation = $relations[0];
            $rs = $rs->related_resultset($relation)->get_cache;
            $rs = $rs->[0]; # Does it makes sense to have several values here?
            my $object_class = Koha::Object::_get_object_class( $rs->result_class );
            my $koha_object = $object_class->_new_from_dbic( $rs );
            $related_resultsets = $rs->{related_resultsets};
            %data = ( %data, %{ $koha_object->unblessed } );
        }
    }
    %data = ( %data, %{ $self->unblessed } );
    return \%data;
}

=head3 $object->_result();

Returns the internal DBIC Row object

=cut

sub _result {
    my ($self) = @_;

    # If we don't have a dbic row at this point, we need to create an empty one
    $self->{_result} ||=
      Koha::Database->new()->schema()->resultset( $self->_type() )->new({});

    return $self->{_result};
}

=head3 $object->_columns();

Returns an arrayref of the table columns

=cut

sub _columns {
    my ($self) = @_;

    # If we don't have a dbic row at this point, we need to create an empty one
    $self->{_columns} ||= [ $self->_result()->result_source()->columns() ];

    return $self->{_columns};
}

sub _get_object_class {
    my ( $type ) = @_;
    return unless $type;

    if( $type->can('koha_object_class') ) {
        return $type->koha_object_class;
    }
    $type =~ s|Schema::Result::||;
    return ${type};
}

=head3 AUTOLOAD

The autoload method is used only to get and set values for an objects properties.

=cut

sub AUTOLOAD {
    my $self = shift;

    my $method = our $AUTOLOAD;
    $method =~ s/.*://;

    my @columns = @{$self->_columns()};
    if ( grep { $_ eq $method } @columns ) {

        # Lazy definition of get/set accessors like $item->barcode; note that it contains $method
        my $accessor = sub {
            my $self = shift;
            if (@_) {
                $self->_result()->set_column( $method, @_ );
                return $self;
            } else {
                return $self->_result()->get_column($method);
            }
        };
        # If called from child class as $self->SUPER-><accessor_name>
        # $AUTOLOAD will contain ::SUPER which breaks method lookup
        # therefore we cannot write those entries into the symbol table
        unless ( $AUTOLOAD =~ /::SUPER::/ ) {
            no strict 'refs'; ## no critic (strict)
            *{$AUTOLOAD} = $accessor;
        }
        return $accessor->( $self, @_ );
    }

    my @known_methods = qw( is_changed id in_storage get_column discard_changes make_column_dirty );

    Koha::Exceptions::Object::MethodNotCoveredByTests->throw(
        error      => sprintf("The method %s->%s is not covered by tests!", ref($self), $method),
        show_trace => 1
    ) unless grep { $_ eq $method } @known_methods;

    my $r = eval { $self->_result->$method(@_) };
    if ( $@ ) {
        Koha::Exceptions::Object->throw( ref($self) . "::$method generated this error: " . $@ );
    }
    return $r;
}

=head3 _type

This method must be defined in the child class. The value is the name of the DBIC resultset.
For example, for borrowers, the _type method will return "Borrower".

=cut

sub _type { }

=head3 _handle_to_api_child

=cut

sub _handle_to_api_child {
    my ($self, $args ) = @_;

    my $child  = $args->{child};
    my $next   = $args->{next};
    my $curr   = $args->{curr};
    my $params = $args->{params};

    my $res;

    if ( defined $child ) {

        Koha::Exception->throw( "Asked to embed $curr but its return value doesn't implement to_api" )
            if defined $next and blessed $child and !$child->can('to_api');

        if ( blessed $child ) {
            $params->{embed} = $next;
            $res = $child->to_api($params);
        }
        else {
            $res = $child;
        }
    }

    return $res;
}

=head3 is_accessible

    if ( $object->is_accessible ) { ... }

Stub method that is expected to be overloaded (if required) by implementing classes.

=cut

sub is_accessible {
    my ($self) = @_;

    return 1;
}

sub DESTROY { }

=head1 AUTHOR

Kyle M Hall <kyle@bywatersolutions.com>

Jonathan Druart <jonathan.druart@bugs.koha-community.org>

=cut

1;
