/*
 * Copyright The WildFly Authors
 * SPDX-License-Identifier: Apache-2.0
 */

package org.jboss.as.subsystem.test.simple.subsystem;

import static org.jboss.as.controller.descriptions.ModelDescriptionConstants.SUBSYSTEM;

import java.util.List;

import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;

import org.jboss.as.controller.Extension;
import org.jboss.as.controller.ExtensionContext;
import org.jboss.as.controller.ModelVersion;
import org.jboss.as.controller.PathAddress;
import org.jboss.as.controller.PathElement;
import org.jboss.as.controller.SimpleResourceDefinition;
import org.jboss.as.controller.SubsystemRegistration;
import org.jboss.as.controller.descriptions.NonResolvingResourceDescriptionResolver;
import org.jboss.as.controller.operations.common.GenericSubsystemDescribeHandler;
import org.jboss.as.controller.operations.common.Util;
import org.jboss.as.controller.parsing.ExtensionParsingContext;
import org.jboss.as.controller.parsing.ParseUtils;
import org.jboss.as.controller.persistence.SubsystemMarshallingContext;
import org.jboss.as.controller.registry.ManagementResourceRegistration;
import org.jboss.dmr.ModelNode;
import org.jboss.staxmapper.XMLElementReader;
import org.jboss.staxmapper.XMLElementWriter;
import org.jboss.staxmapper.XMLExtendedStreamReader;
import org.jboss.staxmapper.XMLExtendedStreamWriter;


/**
 *
 * @author <a href="kabir.khan@jboss.com">Kabir Khan</a>
 */
public class SimpleSubsystemExtension implements Extension {

    /** The name space used for the {@code substystem} element */
    public static final String NAMESPACE = "urn:mycompany:mysubsystem:1.0";

    /** The name of our subsystem within the model. */
    public static final String SUBSYSTEM_NAME = "mysubsystem";

    /** The parser used for parsing our subsystem */
    private final SubsystemParser parser = new SubsystemParser();

    @Override
    public void initializeParsers(ExtensionParsingContext context) {
        context.setSubsystemXmlMapping(SUBSYSTEM_NAME, NAMESPACE, parser);
    }


    @Override
    public void initialize(ExtensionContext context) {
        final SubsystemRegistration subsystem = context.registerSubsystem(SUBSYSTEM_NAME, ModelVersion.create(1));
        final ManagementResourceRegistration registration = subsystem.registerSubsystemModel(new SimpleResourceDefinition(
                PathElement.pathElement(SUBSYSTEM, SUBSYSTEM_NAME),
                NonResolvingResourceDescriptionResolver.INSTANCE,
                SimpleSubsystemAdd.INSTANCE,
                SimpleSubsystemRemove.INSTANCE
        ));
        //We always need to add a 'describe' operation
        registration.registerOperationHandler(GenericSubsystemDescribeHandler.DEFINITION, GenericSubsystemDescribeHandler.INSTANCE);
        subsystem.registerXMLElementWriter(parser);
    }

    /**
    * The subsystem parser, which uses stax to read and write to and from xml
    */
    private static class SubsystemParser implements XMLStreamConstants, XMLElementReader<List<ModelNode>>, XMLElementWriter<SubsystemMarshallingContext> {

        /** {@inheritDoc} */
        @Override
        public void writeContent(XMLExtendedStreamWriter writer, SubsystemMarshallingContext context) throws XMLStreamException {
            context.startSubsystemElement(SimpleSubsystemExtension.NAMESPACE, false);
            writer.writeEndElement();
        }

        /** {@inheritDoc} */
        @Override
        public void readElement(XMLExtendedStreamReader reader, List<ModelNode> list) throws XMLStreamException {
            // Require no content
            ParseUtils.requireNoContent(reader);
            list.add(Util.createAddOperation(PathAddress.pathAddress(PathElement.pathElement(SUBSYSTEM, SUBSYSTEM_NAME))));
        }
    }


}
