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/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */
package org.neo4j.server.rest.repr;

import java.io.IOException;
import java.io.OutputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.net.URI;
import java.nio.charset.StandardCharsets;
import javax.ws.rs.Produces;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriInfo;
import javax.ws.rs.ext.MessageBodyWriter;
import javax.ws.rs.ext.Provider;

import org.neo4j.server.rest.repr.formats.JsonFormat;
import org.neo4j.service.Services;

@Provider
@Produces( MediaType.APPLICATION_JSON )
public class RepresentationBasedMessageBodyWriter implements MessageBodyWriter
{
    private static final JsonFormat JSON_FORMAT = Services.loadAll( RepresentationFormat.class ).stream().filter( JsonFormat.class::isInstance )
                                                          .map( JsonFormat.class::cast ).findFirst()
                                                          .orElseThrow( () -> new RuntimeException( "Could not load JsonFormat" ) );

    @Context
    private UriInfo uriInfo;

    // uriInfo will be injected on a per-request base
    public RepresentationBasedMessageBodyWriter()
    {
    }

    public RepresentationBasedMessageBodyWriter( UriInfo uriInfo )
    {
        this.uriInfo = uriInfo;
    }

    public static String serialize( Representation representation, RepresentationFormat format, URI baseUri )
    {
        return representation.serialize( format, baseUri );
    }

    @Override
    public boolean isWriteable( Class type, Type genericType, Annotation[] annotations, MediaType mediaType )
    {
        return Representation.class.isAssignableFrom( type );
    }

    @Override
    public void writeTo( Representation representation, Class type, Type genericType, Annotation[] annotations, MediaType mediaType,
                         MultivaluedMap httpHeaders, OutputStream entityStream ) throws IOException, WebApplicationException
    {
        var content = serialize( representation, JSON_FORMAT, uriInfo.getBaseUri() );
        entityStream.write( content.getBytes( mediaType.getParameters().getOrDefault( MediaType.CHARSET_PARAMETER, StandardCharsets.UTF_8.name() ) ) );
        entityStream.flush();
    }
}