/*
 * Copyright (c) 2010-2025 Contributors to the openHAB project
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 */
package org.openhab.core.config.core.xml.util;

import java.util.List;
import java.util.Map;
import java.util.Objects;

import org.eclipse.jdt.annotation.NonNullByDefault;
import org.eclipse.jdt.annotation.Nullable;

import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;

/**
 * The {@link NodeListConverter} is a concrete implementation of the {@code XStream} {@link Converter} interface used to
 * convert a list of XML tags within an XML document
 * into a {@link NodeList} object.
 *
 * @author Michael Grammling - Initial contribution
 */
@NonNullByDefault
public class NodeListConverter extends GenericUnmarshaller<NodeList> {

    public NodeListConverter() {
        super(NodeList.class);
    }

    @Override
    public @Nullable Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
        Map<String, String> attributes = ConverterAttributeMapValidator.readValidatedAttributes(reader, null);

        String nodeName = reader.getNodeName();
        List<?> values = (List<?>) context.convertAnother(context, List.class);

        return new NodeList(nodeName, attributes, Objects.requireNonNullElse(values, List.of()));
    }
}
