/*
 * Copyright (c) 2010, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.jaxb.internal;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.nio.charset.Charset;

import jakarta.ws.rs.BadRequestException;
import jakarta.ws.rs.InternalServerErrorException;
import jakarta.ws.rs.WebApplicationException;
import jakarta.ws.rs.core.MediaType;
import jakarta.ws.rs.core.MultivaluedMap;
import jakarta.ws.rs.core.NoContentException;
import jakarta.ws.rs.ext.Providers;

import jakarta.xml.bind.JAXBElement;
import jakarta.xml.bind.JAXBException;
import jakarta.xml.bind.Marshaller;
import jakarta.xml.bind.UnmarshalException;
import jakarta.xml.bind.Unmarshaller;

import org.glassfish.jersey.internal.LocalizationMessages;
import org.glassfish.jersey.message.internal.EntityInputStream;

An abstract provider for JAXBElement. 

Implementing classes may extend this class to provide specific marshalling
and unmarshalling behaviour.
 When unmarshalling a UnmarshalException will result in a WebApplicationException being thrown with a status of 400 (Client error), and a JAXBException will result in a WebApplicationException being thrown with a status of 500 (Internal Server error). 
 When marshalling a JAXBException will result in a WebApplicationException being thrown with a status of 500 (Internal Server error). 
Author:
Paul Sandoz, Marek Potociar/**
 * An abstract provider for {@link JAXBElement}.
 * <p/>
 * Implementing classes may extend this class to provide specific marshalling
 * and unmarshalling behaviour.
 * <p/>
 * When unmarshalling a {@link UnmarshalException} will result in a
 * {@link WebApplicationException} being thrown with a status of 400
 * (Client error), and a {@link JAXBException} will result in a
 * {@link WebApplicationException} being thrown with a status of 500
 * (Internal Server error).
 * <p/>
 * When marshalling a {@link JAXBException} will result in a
 * {@link WebApplicationException} being thrown with a status of 500
 * (Internal Server error).
 *
 * @author Paul Sandoz
 * @author Marek Potociar
 */
public abstract class AbstractJaxbElementProvider extends AbstractJaxbProvider<JAXBElement<?>> {

    
Inheritance constructor.
Params:
providers – JAX-RS providers./**
     * Inheritance constructor.
     *
     * @param providers JAX-RS providers.
     */
    public AbstractJaxbElementProvider(Providers providers) {
        super(providers);
    }

    
Inheritance constructor.
Params:
providers –         JAX-RS providers.
resolverMediaType – JAXB component context resolver media type to be used./**
     * Inheritance constructor.
     *
     * @param providers         JAX-RS providers.
     * @param resolverMediaType JAXB component context resolver media type to be used.
     */
    public AbstractJaxbElementProvider(Providers providers, MediaType resolverMediaType) {
        super(providers, resolverMediaType);
    }

    @Override
    public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
        return type == JAXBElement.class && genericType instanceof ParameterizedType && isSupported(mediaType);
    }

    @Override
    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
        return JAXBElement.class.isAssignableFrom(type) && isSupported(mediaType);
    }

    @Override
    public final JAXBElement<?> readFrom(
            Class<JAXBElement<?>> type,
            Type genericType,
            Annotation[] annotations,
            MediaType mediaType,
            MultivaluedMap<String, String> httpHeaders,
            InputStream inputStream) throws IOException {

        final EntityInputStream entityStream = EntityInputStream.create(inputStream);
        if (entityStream.isEmpty()) {
            throw new NoContentException(LocalizationMessages.ERROR_READING_ENTITY_MISSING());
        }

        final ParameterizedType pt = (ParameterizedType) genericType;
        final Class ta = (Class) pt.getActualTypeArguments()[0];

        try {
            return readFrom(ta, mediaType, getUnmarshaller(ta, mediaType), entityStream);
        } catch (UnmarshalException ex) {
            throw new BadRequestException(ex);
        } catch (JAXBException ex) {
            throw new InternalServerErrorException(ex);
        }
    }

    
Read JAXB element from an entity stream.
Params:
type –         the type that is to be read from the entity stream.
mediaType –    the media type of the HTTP entity.
unmarshaller – JAXB unmarshaller to be used.
entityStream – the InputStream of the HTTP entity. The caller is responsible for ensuring that the input stream ends when the entity has been consumed. The implementation should not close the input stream.
Throws:
JAXBException – in case entity unmarshalling fails.
Returns:
JAXB element representing the entity./**
     * Read JAXB element from an entity stream.
     *
     * @param type         the type that is to be read from the entity stream.
     * @param mediaType    the media type of the HTTP entity.
     * @param unmarshaller JAXB unmarshaller to be used.
     * @param entityStream the {@link InputStream} of the HTTP entity. The
     *                     caller is responsible for ensuring that the input stream ends when the
     *                     entity has been consumed. The implementation should not close the input
     *                     stream.
     * @return JAXB element representing the entity.
     * @throws JAXBException in case entity unmarshalling fails.
     */
    protected abstract JAXBElement<?> readFrom(
            Class<?> type, MediaType mediaType, Unmarshaller unmarshaller, InputStream entityStream) throws JAXBException;

    @Override
    public final void writeTo(
            JAXBElement<?> t,
            Class<?> type,
            Type genericType,
            Annotation[] annotations,
            MediaType mediaType,
            MultivaluedMap<String, Object> httpHeaders,
            OutputStream entityStream) throws IOException {
        try {
            final Marshaller m = getMarshaller(t.getDeclaredType(), mediaType);
            final Charset c = getCharset(mediaType);
            if (c != UTF8) {
                m.setProperty(Marshaller.JAXB_ENCODING, c.name());
            }
            setHeader(m, annotations);
            writeTo(t, mediaType, c, m, entityStream);
        } catch (JAXBException ex) {
            throw new InternalServerErrorException(ex);
        }
    }

    
Write JAXB element to an entity stream.
Params:
element –      JAXB element to be written to an entity stream.
mediaType –    the media type of the HTTP entity.
charset –      character set to be used.
marshaller –   JAXB unmarshaller to be used.
entityStream – the InputStream of the HTTP entity. The caller is responsible for ensuring that the input stream ends when the entity has been consumed. The implementation should not close the input stream.
Throws:
JAXBException – in case entity marshalling fails./**
     * Write JAXB element to an entity stream.
     *
     * @param element      JAXB element to be written to an entity stream.
     * @param mediaType    the media type of the HTTP entity.
     * @param charset      character set to be used.
     * @param marshaller   JAXB unmarshaller to be used.
     * @param entityStream the {@link InputStream} of the HTTP entity. The
     *                     caller is responsible for ensuring that the input stream ends when the
     *                     entity has been consumed. The implementation should not close the input
     *                     stream.
     * @throws JAXBException in case entity marshalling fails.
     */
    protected abstract void writeTo(JAXBElement<?> element,
                                    MediaType mediaType,
                                    Charset charset,
                                    Marshaller marshaller,
                                    OutputStream entityStream) throws JAXBException;
}