/*
 * Copyright (c) 2001-2008 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Hessian", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.alibaba.com.caucho.hessian.io;

import java.io.IOException;
import java.io.OutputStream;

/**
 * Abstract output stream for Hessian requests.
 * <p>
 * <pre>
 * OutputStream os = ...; // from http connection
 * AbstractOutput out = new HessianSerializerOutput(os);
 * String value;
 *
 * out.startCall("hello");  // start hello call
 * out.writeString("arg1"); // write a string argument
 * out.completeCall();      // complete the call
 * </pre>
 */
abstract public class AbstractHessianOutput {
    // serializer factory
    protected SerializerFactory _serializerFactory;

    /**
     * Gets the serializer factory.
     */
    public SerializerFactory getSerializerFactory() {
        return _serializerFactory;
    }

    /**
     * Sets the serializer factory.
     */
    public void setSerializerFactory(SerializerFactory factory) {
        _serializerFactory = factory;
    }

    /**
     * Gets the serializer factory.
     */
    public final SerializerFactory findSerializerFactory() {
        SerializerFactory factory = _serializerFactory;

        if (factory == null)
            _serializerFactory = factory = new SerializerFactory();

        return factory;
    }

    /**
     * Initialize the output with a new underlying stream.
     */
    public void init(OutputStream os) {
    }

    /**
     * Writes a complete method call.
     */
    public void call(String method, Object[] args)
            throws IOException {
        int length = args != null ? args.length : 0;

        startCall(method, length);

        for (int i = 0; i < length; i++)
            writeObject(args[i]);

        completeCall();
    }

    /**
     * Starts the method call:
     * <p>
     * <code><pre>
     * C
     * </pre></code>
     *
     * @param method the method name to call.
     */
    abstract public void startCall()
            throws IOException;

    /**
     * Starts the method call:
     * <p>
     * <code><pre>
     * C string int
     * </pre></code>
     *
     * @param method the method name to call.
     */
    abstract public void startCall(String method, int length)
            throws IOException;

    /**
     * For Hessian 2.0, use the Header envelope instead
     *
     * @deprecated
     */
    public void writeHeader(String name)
            throws IOException {
        throw new UnsupportedOperationException(getClass().getSimpleName());
    }

    /**
     * Writes the method tag.
     * <p>
     * <code><pre>
     * string
     * </pre></code>
     *
     * @param method the method name to call.
     */
    abstract public void writeMethod(String method)
            throws IOException;

    /**
     * Completes the method call:
     * <p>
     * <code><pre>
     * </pre></code>
     */
    abstract public void completeCall()
            throws IOException;

    /**
     * Writes a boolean value to the stream.  The boolean will be written
     * with the following syntax:
     * <p>
     * <code><pre>
     * T
     * F
     * </pre></code>
     *
     * @param value the boolean value to write.
     */
    abstract public void writeBoolean(boolean value)
            throws IOException;

    /**
     * Writes an integer value to the stream.  The integer will be written
     * with the following syntax:
     * <p>
     * <code><pre>
     * I b32 b24 b16 b8
     * </pre></code>
     *
     * @param value the integer value to write.
     */
    abstract public void writeInt(int value)
            throws IOException;

    /**
     * Writes a long value to the stream.  The long will be written
     * with the following syntax:
     * <p>
     * <code><pre>
     * L b64 b56 b48 b40 b32 b24 b16 b8
     * </pre></code>
     *
     * @param value the long value to write.
     */
    abstract public void writeLong(long value)
            throws IOException;

    /**
     * Writes a double value to the stream.  The double will be written
     * with the following syntax:
     * <p>
     * <code><pre>
     * D b64 b56 b48 b40 b32 b24 b16 b8
     * </pre></code>
     *
     * @param value the double value to write.
     */
    abstract public void writeDouble(double value)
            throws IOException;

    /**
     * Writes a date to the stream.
     * <p>
     * <code><pre>
     * T  b64 b56 b48 b40 b32 b24 b16 b8
     * </pre></code>
     *
     * @param time the date in milliseconds from the epoch in UTC
     */
    abstract public void writeUTCDate(long time)
            throws IOException;

    /**
     * Writes a null value to the stream.
     * The null will be written with the following syntax
     * <p>
     * <code><pre>
     * N
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeNull()
            throws IOException;

    /**
     * Writes a string value to the stream using UTF-8 encoding.
     * The string will be written with the following syntax:
     * <p>
     * <code><pre>
     * S b16 b8 string-value
     * </pre></code>
     * <p>
     * If the value is null, it will be written as
     * <p>
     * <code><pre>
     * N
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeString(String value)
            throws IOException;

    /**
     * Writes a string value to the stream using UTF-8 encoding.
     * The string will be written with the following syntax:
     * <p>
     * <code><pre>
     * S b16 b8 string-value
     * </pre></code>
     * <p>
     * If the value is null, it will be written as
     * <p>
     * <code><pre>
     * N
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeString(char[] buffer, int offset, int length)
            throws IOException;

    /**
     * Writes a byte array to the stream.
     * The array will be written with the following syntax:
     * <p>
     * <code><pre>
     * B b16 b18 bytes
     * </pre></code>
     * <p>
     * If the value is null, it will be written as
     * <p>
     * <code><pre>
     * N
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeBytes(byte[] buffer)
            throws IOException;

    /**
     * Writes a byte array to the stream.
     * The array will be written with the following syntax:
     * <p>
     * <code><pre>
     * B b16 b18 bytes
     * </pre></code>
     * <p>
     * If the value is null, it will be written as
     * <p>
     * <code><pre>
     * N
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeBytes(byte[] buffer, int offset, int length)
            throws IOException;

    /**
     * Writes a byte buffer to the stream.
     */
    abstract public void writeByteBufferStart()
            throws IOException;

    /**
     * Writes a byte buffer to the stream.
     * <p>
     * <code><pre>
     * b b16 b18 bytes
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeByteBufferPart(byte[] buffer,
                                             int offset,
                                             int length)
            throws IOException;

    /**
     * Writes the last chunk of a byte buffer to the stream.
     * <p>
     * <code><pre>
     * b b16 b18 bytes
     * </pre></code>
     *
     * @param value the string value to write.
     */
    abstract public void writeByteBufferEnd(byte[] buffer,
                                            int offset,
                                            int length)
            throws IOException;

    /**
     * Writes a reference.
     * <p>
     * <code><pre>
     * Q int
     * </pre></code>
     *
     * @param value the integer value to write.
     */
    abstract protected void writeRef(int value)
            throws IOException;

    /**
     * Removes a reference.
     */
    abstract public boolean removeRef(Object obj)
            throws IOException;

    /**
     * Replaces a reference from one object to another.
     */
    abstract public boolean replaceRef(Object oldRef, Object newRef)
            throws IOException;

    /**
     * Adds an object to the reference list.  If the object already exists,
     * writes the reference, otherwise, the caller is responsible for
     * the serialization.
     * <p>
     * <code><pre>
     * R b32 b24 b16 b8
     * </pre></code>
     *
     * @param object the object to add as a reference.
     * @return true if the object has already been written.
     */
    abstract public boolean addRef(Object object)
            throws IOException;

    /**
     * Resets the references for streaming.
     */
    public void resetReferences() {
    }

    /**
     * Writes a generic object to the output stream.
     */
    abstract public void writeObject(Object object)
            throws IOException;

    /**
     * Writes the list header to the stream.  List writers will call
     * <code>writeListBegin</code> followed by the list contents and then
     * call <code>writeListEnd</code>.
     * <p>
     * <code><pre>
     * V
     *   x13 java.util.ArrayList   # type
     *   x93                       # length=3
     *   x91                       # 1
     *   x92                       # 2
     *   x93                       # 3
     * &lt;/list>
     * </pre></code>
     */
    abstract public boolean writeListBegin(int length, String type)
            throws IOException;

    /**
     * Writes the tail of the list to the stream.
     */
    abstract public void writeListEnd()
            throws IOException;

    /**
     * Writes the map header to the stream.  Map writers will call
     * <code>writeMapBegin</code> followed by the map contents and then
     * call <code>writeMapEnd</code>.
     * <p>
     * <code><pre>
     * M type (<key> <value>)* Z
     * </pre></code>
     */
    abstract public void writeMapBegin(String type)
            throws IOException;

    /**
     * Writes the tail of the map to the stream.
     */
    abstract public void writeMapEnd()
            throws IOException;

    /**
     * Writes the object header to the stream (for Hessian 2.0), or a
     * Map for Hessian 1.0.  Object writers will call
     * <code>writeObjectBegin</code> followed by the map contents and then
     * call <code>writeObjectEnd</code>.
     * <p>
     * <code><pre>
     * C type int <key>*
     * C int <value>*
     * </pre></code>
     *
     * @return true if the object has already been defined.
     */
    public int writeObjectBegin(String type)
            throws IOException {
        writeMapBegin(type);

        return -2;
    }

    /**
     * Writes the end of the class.
     */
    public void writeClassFieldLength(int len)
            throws IOException {
    }

    /**
     * Writes the tail of the object to the stream.
     */
    public void writeObjectEnd()
            throws IOException {
    }

    public void writeReply(Object o)
            throws IOException {
        startReply();
        writeObject(o);
        completeReply();
    }


    public void startReply()
            throws IOException {
    }

    public void completeReply()
            throws IOException {
    }

    public void writeFault(String code, String message, Object detail)
            throws IOException {
    }

    public void flush()
            throws IOException {
    }

    public void close()
            throws IOException {
    }
}