/*

 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package com.sun.xml.internal.ws.commons.xmlutil;

import com.sun.istack.internal.NotNull;

import com.sun.istack.internal.logging.Logger;

import com.sun.xml.internal.ws.api.message.Message;

import com.sun.xml.internal.ws.api.message.Messages;

import com.sun.xml.internal.ws.api.message.Packet;

import com.sun.xml.internal.ws.util.xml.XmlUtil;

import javax.xml.stream.*;

import javax.xml.xpath.XPathFactoryConfigurationException;

import java.io.*;

import java.lang.reflect.Constructor;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.logging.Level;

/**

 * Utility class that provides conversion of different XML representations

 * from/to various other formats

 *

 * @author Marek Potociar

 */

public final class Converter {

    public static final String UTF_8 = "UTF-8";

    private Converter() {

        // prevents instantiation

    }

    private static final Logger LOGGER = Logger.getLogger(Converter.class);

    private static final ContextClassloaderLocal<XMLOutputFactory> xmlOutputFactory = new ContextClassloaderLocal<XMLOutputFactory>() {

        @Override

        protected XMLOutputFactory initialValue() throws Exception {

            return XMLOutputFactory.newInstance();

        }

    };

    private static final AtomicBoolean logMissingStaxUtilsWarning = new AtomicBoolean(false);

    /**

     * Converts a throwable to String

     *

     * @param throwable

     * @return String representation of throwable

     */

    public static String toString(Throwable throwable) {

        if (throwable == null) {

            return "[ No exception ]";

        }

        StringWriter stringOut = new StringWriter();

        throwable.printStackTrace(new PrintWriter(stringOut));

        return stringOut.toString();

    }

    public static String toString(Packet packet) {

        if (packet == null) {

            return "[ Null packet ]";

        } else if (packet.getMessage() == null) {

                return "[ Empty packet ]";

        }

        return toString(packet.getMessage());

    }

    public static String toStringNoIndent(Packet packet) {

        if (packet == null) {

            return "[ Null packet ]";

        } else if (packet.getMessage() == null) {

                return "[ Empty packet ]";

        }

        return toStringNoIndent(packet.getMessage());

    }

    public static String toString(Message message) {

        return toString(message, true);

    }

    public static String toStringNoIndent(Message message) {

        return toString(message, false);

    }

    private static String toString(Message message, boolean createIndenter) {

        if (message == null) {

            return "[ Null message ]";

        }

        StringWriter stringOut = null;

        try {

            stringOut = new StringWriter();

            XMLStreamWriter writer = null;

            try {

                writer = xmlOutputFactory.get().createXMLStreamWriter(stringOut);

                if (createIndenter) {

                    writer = createIndenter(writer);

                }

                message.copy().writeTo(writer);

            } catch (Exception e) { // WSIT-1596 - Message Dumping should not affect other processing

                LOGGER.log(Level.WARNING, "Unexpected exception occured while dumping message", e);

            } finally {

                if (writer != null) {

                    try {

                        writer.close();

                    } catch (XMLStreamException ignored) {

                        LOGGER.fine("Unexpected exception occured while closing XMLStreamWriter", ignored);

                    }

                }

            }

            return stringOut.toString();

        } finally {

            if (stringOut != null) {

                try {

                    stringOut.close();

                } catch (IOException ex) {

                    LOGGER.finest("An exception occured when trying to close StringWriter", ex);

                }

            }

        }

    }

    public static byte[] toBytes(Message message, String encoding) throws XMLStreamException {

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        try {

            if (message != null) {

                XMLStreamWriter xsw = xmlOutputFactory.get().createXMLStreamWriter(baos, encoding);

                try {

                    message.writeTo(xsw);

                } finally {

                    try {

                        xsw.close();

                    } catch (XMLStreamException ex) {

                        LOGGER.warning("Unexpected exception occured while closing XMLStreamWriter", ex);

                    }

                }

            }

            return baos.toByteArray();

        } finally {

            try {

                baos.close();

            } catch (IOException ex) {

                LOGGER.warning("Unexpected exception occured while closing ByteArrayOutputStream", ex);

            }

        }

    }

    /**

     * Converts JAX-WS RI message represented as input stream back to Message

     * object.

     *

     * @param dataStream message data stream

     * @param encoding message data stream encoding

     *

     * @return {@link com.sun.xml.internal.ws.api.message.Message} object created from the data stream

     */

    public static Message toMessage(@NotNull InputStream dataStream, String encoding) throws XMLStreamException {

        XMLStreamReader xsr = XmlUtil.newXMLInputFactory(true).createXMLStreamReader(dataStream, encoding);

        return Messages.create(xsr);

    }

    public static String messageDataToString(final byte[] data, final String encoding) {

        try {

            return toString(toMessage(new ByteArrayInputStream(data), encoding));

            // closing ByteArrayInputStream has no effect, so ignoring the redundant call

        } catch (XMLStreamException ex) {

            LOGGER.warning("Unexpected exception occured while converting message data to string", ex);

            return "[ Message Data Conversion Failed ]";

        }

    }

    /**

     * Wraps {@link javax.xml.stream.XMLStreamWriter} by an indentation engine if possible.

     *

     * <p>

     */

    private static XMLStreamWriter createIndenter(XMLStreamWriter writer) {

        try {

            Class<?> clazz = Converter.class.getClassLoader().loadClass("javanet.staxutils.IndentingXMLStreamWriter");

            Constructor<?> c = clazz.getConstructor(XMLStreamWriter.class);

            writer = XMLStreamWriter.class.cast(c.newInstance(writer));

        } catch (Exception ex) {

            // if stax-utils.jar is not in the classpath, this will fail

            // so, we'll just have to do without indentation

            if (logMissingStaxUtilsWarning.compareAndSet(false, true)) {

                LOGGER.log(Level.WARNING, "Put stax-utils.jar to the classpath to indent the dump output", ex);

            }

        }

        return writer;

    }

}