package net.sourceforge.jsocks;

import java.net.*;
import java.io.*;

/**
 * SocksSocket tryies to look very similar to normal Socket,
 * while allowing connections through the SOCKS4 or 5 proxy.
 * To use this class you will have to identify proxy you need
 * to use, Proxy class allows you to set default proxy, which
 * will be used by all Socks aware sockets. You can also create
 * either Socks4Proxy or Socks5Proxy, and use them by passing to the
 * appropriate constructors.
 * <P>
 * Using Socks package can be as easy as that:
 *
 * <pre><tt>
 *
 *     import Socks.*;
 *     ....
 *
 *     try{
 *        //Specify SOCKS5 proxy
 *        Proxy.setDefaultProxy("socks-proxy",1080);
 *
 *        //OR you still use SOCKS4
 *        //Code below uses SOCKS4 proxy
 *        //Proxy.setDefaultProxy("socks-proxy",1080,userName);
 *
 *        Socket s = SocksSocket("some.host.of.mine",13);
 *        readTimeFromSock(s);
 *     }catch(SocksException sock_ex){
 *        //Usually it will turn in more or less meaningfull message
 *        System.err.println("SocksException:"+sock_ex);
 *     }
 *
 * </tt></pre>
 *<P>
 * However if the need exist for more control, like resolving addresses
 * remotely, or using some non-trivial authentication schemes, it can be done.
 */

public class SocksSocket extends Socket {
    //Data members
    protected Proxy proxy;
    protected String localHost, remoteHost;
    protected InetAddress localIP, remoteIP;
    protected int localPort, remotePort;

    private Socket directSock = null;

    /**
     * Tryies to connect to given host and port
     * using default proxy. If no default proxy speciefied
     * it throws SocksException with error code SOCKS_NO_PROXY.
       @param host Machine to connect to.
       @param port Port to which to connect.
     * @see SocksSocket#SocksSocket(Proxy,String,int)
     * @see Socks5Proxy#resolveAddrLocally
     */
    public SocksSocket(String host, int port)
    throws SocksException, UnknownHostException {
        this(Proxy.defaultProxy, host, port);
    }
    /**
     * Connects to host port using given proxy server.
       @param p Proxy to use.
       @param host Machine to connect to.
       @param port Port to which to connect.
       @throws UnknownHostException
       If one of the following happens:
       <ol>

       <li> Proxy settings say that address should be resolved locally, but
            this fails.
       <li> Proxy settings say that the host should be contacted directly but
            host name can't be resolved.
       </ol>
       @throws SocksException
       If one of the following happens:
       <ul>
        <li> Proxy is is null.
        <li> Proxy settings say that the host should be contacted directly but
             this fails.
        <li> Socks Server can't be contacted.
        <li> Authentication fails.
        <li> Connection is not allowed by the SOCKS proxy.
        <li> SOCKS proxy can't establish the connection.
        <li> Any IO error occured.
        <li> Any protocol error occured.
       </ul>
       @throws IOexception if anything is wrong with I/O.
       @see Socks5Proxy#resolveAddrLocally
     */
    public SocksSocket(Proxy p, String host, int port) throws SocksException,
        UnknownHostException {
        remoteHost = host;
        remotePort = port;
        remoteIP = InetAddress.getByName(host);
        doDirect();
    }

    /**
       Connects to given ip and port using given Proxy server.
       @param p Proxy to use.
       @param ip Machine to connect to.
       @param port Port to which to connect.

     */
    public SocksSocket(InetAddress ip, int port) throws SocksException {
        this.remoteIP = ip;
        this.remotePort = port;
        this.remoteHost = ip.getHostName();
        doDirect();
    }


    /**
     * These 2 constructors are used by the SocksServerSocket.
     * This socket simply overrides remoteHost, remotePort
     */
    protected SocksSocket(String  host, int port, Proxy proxy) {
        this.remotePort = port;
        this.proxy = proxy;
        this.localIP = proxy.proxySocket.getLocalAddress();
        this.localPort = proxy.proxySocket.getLocalPort();
        this.remoteHost = host;
    }
    protected SocksSocket(InetAddress ip, int port, Proxy proxy) {
        remoteIP = ip;
        remotePort = port;
        this.proxy = proxy;
        this.localIP = proxy.proxySocket.getLocalAddress();
        this.localPort = proxy.proxySocket.getLocalPort();
        remoteHost = remoteIP.getHostName();
    }

    /**
     * Same as Socket
     */
    public void close() throws IOException {
        if (proxy != null)proxy.endSession();

        proxy = null;
    }
    /**
     * Same as Socket
     */
    public InputStream getInputStream() {
        return proxy.in;
    }
    /**
     * Same as Socket
     */
    public OutputStream getOutputStream() {
        return proxy.out;
    }
    /**
     * Same as Socket
     */
    public int getPort() {
        return remotePort;
    }
    /**
     * Returns remote host name, it is usefull in cases when addresses
     * are resolved by proxy, and we can't create InetAddress object.
       @return The name of the host this socket is connected to.
     */
    public String getHost() {
        return remoteHost;
    }
    /**
     * Get remote host as InetAddress object, might return null if
     * addresses are resolved by proxy, and it is not possible to resolve
     * it locally
       @return Ip address of the host this socket is connected to, or null
       if address was returned by the proxy as DOMAINNAME and can't be
       resolved locally.
     */
    public InetAddress getInetAddress() {
        if (remoteIP == null) {
            try {
                remoteIP = InetAddress.getByName(remoteHost);
            }
            catch (UnknownHostException e) {
                return null;
            }
        }

        return remoteIP;
    }

    /**
     * Get the port assigned by the proxy for the socket, not
     * the port on locall machine as in Socket.
       @return Port of the socket used on the proxy server.
     */
    public int getLocalPort() {
        return localPort;
    }

    /**
     * Get address assigned by proxy to make a remote connection,
     * it might be different from the host specified for the proxy.
     * Can return null if socks server returned this address as hostname
     * and it can't be resolved locally, use getLocalHost() then.
       @return Address proxy is using to make a connection.
     */
    public InetAddress getLocalAddress() {
        if (localIP == null) {
            try {
                localIP = InetAddress.getByName(localHost);
            }
            catch (UnknownHostException e) {
                return null;
            }
        }

        return localIP;
    }
    /**
       Get name of the host, proxy has assigned to make a remote connection
       for this socket. This method is usefull when proxy have returned
       address as hostname, and we can't resolve it on this machine.
       @return The name of the host proxy is using to make a connection.
    */
    public String getLocalHost() {
        return localHost;
    }

    /**
      Same as socket.
    */
    public void setSoLinger(boolean on, int val) throws SocketException {
        proxy.proxySocket.setSoLinger(on, val);
    }
    /**
      Same as socket.
    */
    public int getSoLinger(int timeout) throws SocketException {
        return proxy.proxySocket.getSoLinger();
    }
    /**
      Same as socket.
    */
    public void setSoTimeout(int timeout) throws SocketException {
        proxy.proxySocket.setSoTimeout(timeout);
    }
    /**
      Same as socket.
    */
    public int getSoTimeout(int timeout) throws SocketException {
        return proxy.proxySocket.getSoTimeout();
    }
    /**
      Same as socket.
    */
    public void setTcpNoDelay(boolean on) throws SocketException {
        proxy.proxySocket.setTcpNoDelay(on);
    }
    /**
      Same as socket.
    */
    public boolean getTcpNoDelay() throws SocketException {
        return proxy.proxySocket.getTcpNoDelay();
    }

    /**
      Get string representation of the socket.
    */
    public String toString() {
        if (directSock != null) return "Direct connection:" + directSock;

        return ("Proxy:" + proxy + ";" + "addr:" + remoteHost + ",port:" + remotePort
                + ",localport:" + localPort);
    }

//Private Methods
//////////////////

    private void doDirect()throws SocksException {
        try {
            //System.out.println("IP:"+remoteIP+":"+remotePort);
            directSock = new Socket(remoteIP, remotePort);
            proxy.out = directSock.getOutputStream();
            proxy.in  = directSock.getInputStream();
            proxy.proxySocket = directSock;
            localIP = directSock.getLocalAddress();
            localPort = directSock.getLocalPort();
        }
        catch (IOException io_ex) {
            throw new SocksException(Proxy.SOCKS_DIRECT_FAILED,
                                     "Direct connect failed:" + io_ex);
        }
    }

}