# --
# Copyright (C) 2001-2021 OTRS AG, https://otrs.com/
# Copyright (C) 2021 Znuny GmbH, https://znuny.org/
# --
# This software comes with ABSOLUTELY NO WARRANTY. For details, see
# the enclosed file COPYING for license information (GPL). If you
# did not receive this file, see https://www.gnu.org/licenses/gpl-3.0.txt.
# --
## nofilter(TidyAll::Plugin::Znuny::Perl::Pod::NamePod)

package scripts::Migration::Base::DatabaseDefaultStorageEngineCheck;    ## no critic

use strict;
use warnings;
use utf8;

use parent qw(scripts::Migration::Base);

use version;

our @ObjectDependencies = (
    'Kernel::System::DB',
);

=head1 SYNOPSIS

Checks if MySQL database has the correct default storage engine.

=cut

=head2 CheckPreviousRequirement()

Check for initial conditions for running this migration step.

Returns 1 on success:

    my $Result = $MigrateToZnunyObject->CheckPreviousRequirement();

=cut

sub CheckPreviousRequirement {
    my ( $Self, %Param ) = @_;

    my $Verbose = $Param{CommandlineOptions}->{Verbose} || 0;

    my $DBObject = $Kernel::OM->Get('Kernel::System::DB');

    # This check makes sense only for MySQL, so skip it in case of other back-ends.
    if ( $DBObject->GetDatabaseFunction('Type') ne 'mysql' ) {
        if ($Verbose) {
            print "    Database backend is not MySQL, skipping...\n";
        }
        return 1;
    }

    my $IsInnoDB             = 0;
    my $DefaultStorageEngine = "";

    # Check client character set.
    $DBObject->Prepare( SQL => "show variables like 'default_storage_engine'" );
    while ( my @Row = $DBObject->FetchrowArray() ) {
        $DefaultStorageEngine = $Row[1];
        if ( $DefaultStorageEngine =~ /^InnoDB$/i ) {
            $IsInnoDB = 1;
        }
    }

    if ( !$IsInnoDB ) {
        print "    Error: Setting default_storage_engine needs to be InnoDB.\n";
        return;
    }

    if ($Verbose) {
        print "    The setting default_storage_engine is: $DefaultStorageEngine. ";
    }

    return 1;
}

1;

=head1 TERMS AND CONDITIONS

This software is part of the OTRS project (L<https://otrs.org/>).

This software comes with ABSOLUTELY NO WARRANTY. For details, see
the enclosed file COPYING for license information (GPL). If you
did not receive this file, see L<https://www.gnu.org/licenses/gpl-3.0.txt>.

=cut
