/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.tika.parser.xml;

import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import org.apache.commons.io.input.CloseShieldInputStream;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;

import org.apache.tika.exception.TikaException;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.parser.AbstractParser;
import org.apache.tika.parser.ParseContext;
import org.apache.tika.sax.EmbeddedContentHandler;
import org.apache.tika.sax.OfflineContentHandler;
import org.apache.tika.sax.TaggedContentHandler;
import org.apache.tika.sax.TextContentHandler;
import org.apache.tika.sax.XHTMLContentHandler;
import org.apache.tika.utils.XMLReaderUtils;

/**
 * XML parser.
 */
public class XMLParser extends AbstractParser {

    /**
     * Serial version UID
     */
    private static final long serialVersionUID = -6028836725280212837L;

    private static final Set<MediaType> SUPPORTED_TYPES = Collections.unmodifiableSet(
        new HashSet<>(
            Arrays.asList(MediaType.application("xml"), MediaType.image("svg+xml"))));

    public Set<MediaType> getSupportedTypes(ParseContext context) {
        return SUPPORTED_TYPES;
    }

    public void parse(InputStream stream, ContentHandler handler, Metadata metadata,
                      ParseContext context) throws IOException, SAXException, TikaException {
        if (metadata.get(Metadata.CONTENT_TYPE) == null) {
            metadata.set(Metadata.CONTENT_TYPE, "application/xml");
        }

        final XHTMLContentHandler xhtml = new XHTMLContentHandler(handler, metadata);
        xhtml.startDocument();
        xhtml.startElement("p");

        TaggedContentHandler tagged = new TaggedContentHandler(handler);
        try {
            XMLReaderUtils.parseSAX(new CloseShieldInputStream(stream), new OfflineContentHandler(
                    new EmbeddedContentHandler(
                        getContentHandler(tagged, metadata, context))),
                context);
        } catch (SAXException e) {
            tagged.throwIfCauseOf(e);
            throw new TikaException("XML parse error", e);
        } finally {
            xhtml.endElement("p");
            xhtml.endDocument();
        }
    }

    protected ContentHandler getContentHandler(ContentHandler handler, Metadata metadata,
                                               ParseContext context) {
        return new TextContentHandler(handler, true);
    }
}
