use Koha::Item::Transfer::Limits;

use Koha::Libraries;

use Koha::Exceptions::Library;

=head3 can_be_transferred

$biblio->can_be_transferred({ to => $to_library, from => $from_library })

Checks if at least one item of a biblio can be transferred to given library.

This feature is controlled by two system preferences:

UseBranchTransferLimits to enable / disable the feature

BranchTransferLimitsType to use either an itemnumber or ccode as an identifier

                         for setting the limitations

Performance-wise, it is recommended to use this method for a biblio instead of

iterating each item of a biblio with Koha::Item->can_be_transferred().

Takes HASHref that can have the following parameters:

    MANDATORY PARAMETERS:

    $to   : Koha::Library or branchcode string

    OPTIONAL PARAMETERS:

    $from : Koha::Library or branchcode string  # if given, only items from that

                                                # holdingbranch are considered

Returns 1 if at least one of the item of a biblio can be transferred

to $to_library, otherwise 0.

=cut

sub can_be_transferred {

    my ($self, $params) = @_;

    my $to = $params->{'to'};

    my $from = $params->{'from'};

    if (ref($to) ne 'Koha::Library') {

        my $tobranchcode = defined $to ? $to : '';

        $to = Koha::Libraries->find($tobranchcode);

        unless ($to) {

            Koha::Exceptions::Library::NotFound->throw(

                error => "Library '$tobranchcode' not found.",

            );

        }

    }

    if ($from && ref($from) ne 'Koha::Library') {

        my $frombranchcode = defined $from ? $from : '';

        $from = Koha::Libraries->find($frombranchcode);

        unless ($from) {

            Koha::Exceptions::Library::NotFound->throw(

                error => "Library '$frombranchcode' not found.",

            );

        }

    }

    return 1 unless C4::Context->preference('UseBranchTransferLimits');

    my $limittype = C4::Context->preference('BranchTransferLimitsType');

    my $items;

    foreach my $item_of_bib ($self->items) {

        next unless $item_of_bib->holdingbranch;

        next if $from && $from->branchcode ne $item_of_bib->holdingbranch;

        return 1 if $item_of_bib->holdingbranch eq $to->branchcode;

        my $code = $limittype eq 'itemtype'

            ? $item_of_bib->effective_itemtype

            : $item_of_bib->ccode;

        return 1 unless $code;

        $items->{$code}->{$item_of_bib->holdingbranch} = 1;

    }

    # At this point we will have a HASHref containing each itemtype/ccode that

    # this biblio has, inside which are all of the holdingbranches where those

    # items are located at. Then, we will query Koha::Item::Transfer::Limits to

    # find out whether a transfer limits for such $limittype from any of the

    # listed holdingbranches to the given $to library exist. If at least one

    # holdingbranch for that $limittype does not have a transfer limit to given

    # $to library, then we know that the transfer is possible.

    foreach my $code (keys %{$items}) {

        my @holdingbranches = keys %{$items->{$code}};

        return 1 if Koha::Item::Transfer::Limits->search({

            toBranch => $to->branchcode,

            fromBranch => { 'in' => \@holdingbranches },

            $limittype => $code

        }, {

            group_by => [qw/fromBranch/]

        })->count == scalar(@holdingbranches) ? 0 : 1;

    }

    return 0;

}

To find out whether at least one item of a Koha::Biblio can be transferred, please

see Koha::Biblio->can_be_transferred() instead of using this method for

multiple items of the same biblio.

use C4::Biblio;

use C4::Items;

subtest 'can_be_transferred' => sub {

    plan tests => 11;

    t::lib::Mocks::mock_preference('UseBranchTransferLimits', 1);

    t::lib::Mocks::mock_preference('BranchTransferLimitsType', 'itemtype');

    my $library1 = $builder->build( { source => 'Branch' } )->{branchcode};

    my $library2 = $builder->build( { source => 'Branch' } )->{branchcode};

    my $library3 = $builder->build( { source => 'Branch' } )->{branchcode};

    my ($bibnum, $title, $bibitemnum) = create_helper_biblio('ONLY1');

    my ($item_bibnum, $item_bibitemnum, $itemnumber)

        = AddItem({ homebranch => $library1, holdingbranch => $library1 }, $bibnum);

    my $item  = Koha::Items->find($itemnumber);

    my $biblio = Koha::Biblios->find($bibnum);

    is(Koha::Item::Transfer::Limits->search({

        fromBranch => $library1,

        toBranch => $library2,

    })->count, 0, 'There are no transfer limits between libraries.');

    ok($biblio->can_be_transferred({ to => $library2 }),

        'Some items of this biblio can be transferred between libraries.');

    my $limit = Koha::Item::Transfer::Limit->new({

        fromBranch => $library1,

        toBranch => $library2,

        itemtype => $item->effective_itemtype,

    })->store;

    is(Koha::Item::Transfer::Limits->search({

        fromBranch => $library1,

        toBranch => $library2,

    })->count, 1, 'Given we have added a transfer limit that applies for all '

        .'of this biblio\s items,');

    is($biblio->can_be_transferred({ to => $library2 }), 0,

        'None of the items of biblio can no longer be transferred between '

        .'libraries.');

    is($biblio->can_be_transferred({ to => $library2, from => $library1 }), 0,

         'We get the same result also if we pass the from-library parameter.');

    $item->holdingbranch($library2)->store;

    is($biblio->can_be_transferred({ to => $library2 }), 1, 'Given one of the '

         .'items is already located at to-library, then the transfer is possible.');

    $item->holdingbranch($library1)->store;

    my ($item_bibnum2, $item_bibitemnum2, $itemnumber2)

        = AddItem({ homebranch => $library1, holdingbranch => $library3 }, $bibnum);

    my $item2  = Koha::Items->find($itemnumber2);

    is($biblio->can_be_transferred({ to => $library2 }), 1, 'Given we added '

        .'another item that should have no transfer limits applying on, then '

        .'the transfer is possible.');

    $item2->holdingbranch($library1)->store;

    is($biblio->can_be_transferred({ to => $library2 }), 0, 'Given all of items'

        .' of the biblio are from same, transfer limited library, then transfer'

        .' is not possible.');

    eval { $biblio->can_be_transferred({ to => undef }); };

    is(ref($@), 'Koha::Exceptions::Library::NotFound', 'Exception thrown when no'

        .' library given.');

    eval { $biblio->can_be_transferred({ to => 'heaven' }); };

    is(ref($@), 'Koha::Exceptions::Library::NotFound', 'Exception thrown when'

        .' invalid library is given.');

    eval { $biblio->can_be_transferred({ to => $library2, from => 'hell' }); };

    is(ref($@), 'Koha::Exceptions::Library::NotFound', 'Exception thrown when'

        .' invalid library is given.');

};

# Helper method to set up a Biblio.

sub create_helper_biblio {

    my $itemtype = shift;

    my ($bibnum, $title, $bibitemnum);

    my $bib = MARC::Record->new();

    $title = 'Silence in the library';

    $bib->append_fields(

        MARC::Field->new('100', ' ', ' ', a => 'Moffat, Steven'),

        MARC::Field->new('245', ' ', ' ', a => $title),

        MARC::Field->new('942', ' ', ' ', c => $itemtype),

    );

    return ($bibnum, $title, $bibitemnum) = AddBiblio($bib, '');

}