/*

 * ====================================================================

 * 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.

 * ====================================================================

 *

 * This software consists of voluntary contributions made by many

 * individuals on behalf of the Apache Software Foundation.  For more

 * information on the Apache Software Foundation, please see

 * <http://www.apache.org/>.

 *

 */



package org.apache.http.impl;



import java.io.IOException;

import java.net.InetAddress;

import java.net.Socket;

import java.net.SocketException;



import org.apache.http.HttpInetConnection;

import org.apache.http.impl.io.SocketInputBuffer;

import org.apache.http.impl.io.SocketOutputBuffer;

import org.apache.http.io.SessionInputBuffer;

import org.apache.http.io.SessionOutputBuffer;

import org.apache.http.params.HttpConnectionParams;

import org.apache.http.params.HttpParams;



/**

 * Implementation of a server-side HTTP connection that can be bound to a 

 * network Socket in order to receive and transmit data.

 * <p>

 * The following parameters can be used to customize the behavior of this 

 * class: 

 * <ul>

 *  <li>{@link org.apache.http.params.CoreProtocolPNames#STRICT_TRANSFER_ENCODING}</li>

 *  <li>{@link org.apache.http.params.CoreProtocolPNames#HTTP_ELEMENT_CHARSET}</li>

 *  <li>{@link org.apache.http.params.CoreConnectionPNames#SOCKET_BUFFER_SIZE}</li>

 *  <li>{@link org.apache.http.params.CoreConnectionPNames#MAX_LINE_LENGTH}</li>

 *  <li>{@link org.apache.http.params.CoreConnectionPNames#MAX_HEADER_COUNT}</li>

 * </ul>

 * 

 * @since 4.0

 */

public class SocketHttpServerConnection extends 

        AbstractHttpServerConnection implements HttpInetConnection {



    private volatile boolean open;

    private volatile Socket socket = null;

    

    public SocketHttpServerConnection() {

        super();

    }



    protected void assertNotOpen() {

        if (this.open) {

            throw new IllegalStateException("Connection is already open");

        }

    }

    

    protected void assertOpen() {

        if (!this.open) {

            throw new IllegalStateException("Connection is not open");

        }

    }

    

    /**

     * @deprecated Use {@link #createSessionInputBuffer(Socket, int, HttpParams)}

     */

    protected SessionInputBuffer createHttpDataReceiver(

            final Socket socket, 

            int buffersize,

            final HttpParams params) throws IOException {

        return createSessionInputBuffer(socket, buffersize, params);

    }

    

    /**

     * @deprecated Use {@link #createSessionOutputBuffer(Socket, int, HttpParams)}

     */

    protected SessionOutputBuffer createHttpDataTransmitter(

            final Socket socket, 

            int buffersize,

            final HttpParams params) throws IOException {

        return createSessionOutputBuffer(socket, buffersize, params);

    }



    /**

     * Creates an instance of {@link SocketInputBuffer} to be used for 

     * receiving data from the given {@link Socket}.

     * <p>

     * This method can be overridden in a super class in order to provide 

     * a custom implementation of {@link SessionInputBuffer} interface.

     * 

     * @see SocketInputBuffer#SocketInputBuffer(Socket, int, HttpParams)

     * 

     * @param socket the socket.

     * @param buffersize the buffer size.

     * @param params HTTP parameters.

     * @return session input buffer.

     * @throws IOException in case of an I/O error.

     */

    protected SessionInputBuffer createSessionInputBuffer(

            final Socket socket, 

            int buffersize,

            final HttpParams params) throws IOException {

        return new SocketInputBuffer(socket, buffersize, params);

    }

    

    /**

     * Creates an instance of {@link SessionOutputBuffer} to be used for 

     * sending data to the given {@link Socket}.

     * <p>

     * This method can be overridden in a super class in order to provide 

     * a custom implementation of {@link SocketOutputBuffer} interface.

     * 

     * @see SocketOutputBuffer#SocketOutputBuffer(Socket, int, HttpParams)

     * 

     * @param socket the socket.

     * @param buffersize the buffer size.

     * @param params HTTP parameters.

     * @return session output buffer.

     * @throws IOException in case of an I/O error.

     */

    protected SessionOutputBuffer createSessionOutputBuffer(

            final Socket socket, 

            int buffersize,

            final HttpParams params) throws IOException {

        return new SocketOutputBuffer(socket, buffersize, params);

    }

    

    /**

     * Binds this connection to the given {@link Socket}. This socket will be 

     * used by the connection to send and receive data.

     * <p>

     * This method will invoke {@link #createSessionInputBuffer(Socket, int, HttpParams)}

     * and {@link #createSessionOutputBuffer(Socket, int, HttpParams)} methods 

     * to create session input / output buffers bound to this socket and then 

     * will invoke {@link #init(SessionInputBuffer, SessionOutputBuffer, HttpParams)} 

     * method to pass references to those buffers to the underlying HTTP message

     * parser and formatter. 

     * <p>

     * After this method's execution the connection status will be reported

     * as open and the {@link #isOpen()} will return <code>true</code>.

     * 

     * @param socket the socket.

     * @param params HTTP parameters.

     * @throws IOException in case of an I/O error.

     */

    protected void bind(final Socket socket, final HttpParams params) throws IOException {

        if (socket == null) {

            throw new IllegalArgumentException("Socket may not be null");

        }

        if (params == null) {

            throw new IllegalArgumentException("HTTP parameters may not be null");

        }

        this.socket = socket;

        

        int buffersize = HttpConnectionParams.getSocketBufferSize(params);

        

        init(

                createHttpDataReceiver(socket, buffersize, params), 

                createHttpDataTransmitter(socket, buffersize, params),

                params);

        

        this.open = true;

    }



    protected Socket getSocket() {

        return this.socket;

    }



    public boolean isOpen() {

        return this.open;

    }



    public InetAddress getLocalAddress() {

        if (this.socket != null) {

            return this.socket.getLocalAddress();

        } else {

            return null;

        }

    }



    public int getLocalPort() {

        if (this.socket != null) {

            return this.socket.getLocalPort();

        } else {

            return -1;

        }

    }



    public InetAddress getRemoteAddress() {

        if (this.socket != null) {

            return this.socket.getInetAddress();

        } else {

            return null;

        }

    }



    public int getRemotePort() {

        if (this.socket != null) {

            return this.socket.getPort();

        } else {

            return -1;

        }

    }



    public void setSocketTimeout(int timeout) {

        assertOpen();

        if (this.socket != null) {

            try {

                this.socket.setSoTimeout(timeout);

            } catch (SocketException ignore) {

                // It is not quite clear from the Sun's documentation if there are any 

                // other legitimate cases for a socket exception to be thrown when setting 

                // SO_TIMEOUT besides the socket being already closed

            }

        }

    }

    

    public int getSocketTimeout() {

        if (this.socket != null) {

            try {

                return this.socket.getSoTimeout();

            } catch (SocketException ignore) {

                return -1;

            }

        } else {

            return -1;

        }

    }



    public void shutdown() throws IOException {

        this.open = false;

        Socket tmpsocket = this.socket;

        if (tmpsocket != null) {

            tmpsocket.close();

        }

    }

    

    public void close() throws IOException {

        if (!this.open) {

            return;

        }

        this.open = false;

        this.open = false;

        Socket sock = this.socket;

        try {

            doFlush();

            try {

                try {

                    sock.shutdownOutput();

                } catch (IOException ignore) {

                }

                try {

                    sock.shutdownInput();

                } catch (IOException ignore) {

                }

            } catch (UnsupportedOperationException ignore) {

                // if one isn't supported, the other one isn't either

            }

        } finally {

            sock.close();

        }

    }

    

}