/*
 * Copyright (c) 2023, NVIDIA CORPORATION.  All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cdi

import (
	"k8s.io/klog/v2"
)

type null struct{}

var _ Interface = &null{}

// NewNullHandler returns an instance of the 'cdi' interface that can
// be used when CDI specs are not required.
func NewNullHandler() Interface {
	return &null{}
}

// CreateSpecFile is a no-op for the null handler.
func (n *null) CreateSpecFile() error {
	return nil
}

// QualifiedName is a no-op for the null handler. A error message is logged
// inidicating this should never be called for the null handler.
func (n *null) QualifiedName(class string, id string) string {
	klog.Error("cannot return a qualified CDI device name with the null CDI handler")
	return ""
}
