//
//  Copyright (C) 2001 Const Kaplinsky.  All Rights Reserved.
//  Copyright (C) 2000 Tridia Corporation.  All Rights Reserved.
//  Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
//
//  This is free software; you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation; either version 2 of the License, or
//  (at your option) any later version.
//
//  This software 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 for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this software; if not, write to the Free Software
//  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
//  USA.
//

//
// rfbProto.java
//

import java.io.*;
import java.awt.*;
import java.net.Socket;

/*
class myInputStream extends FilterInputStream {
  public myInputStream(InputStream in) {
    super(in);
  }
  public int read(byte[] b, int off, int len) throws IOException {
    System.out.println("read(byte[] b, int off, int len) called");
    return super.read(b, off, len);
  }
}
*/

class rfbProto {

  final String versionMsg = "RFB 003.003\n";
  final static int ConnFailed = 0, NoAuth = 1, VncAuth = 2;
  final static int VncAuthOK = 0, VncAuthFailed = 1, VncAuthTooMany = 2;

  final static int FramebufferUpdate = 0, SetColourMapEntries = 1, Bell = 2,
    ServerCutText = 3;

  final int SetPixelFormat = 0, FixColourMapEntries = 1, SetEncodings = 2,
    FramebufferUpdateRequest = 3, KeyEvent = 4, PointerEvent = 5,
    ClientCutText = 6;

  final static int EncodingRaw = 0, EncodingCopyRect = 1,
    EncodingRRE = 2, EncodingCoRRE = 4, EncodingHextile = 5,
    EncodingZlib = 6, EncodingTight = 7, EncodingCompressLevel0 = 0xFFFFFF00,
    EncodingXCursor = 0xFFFFFF10, EncodingRichCursor = 0xFFFFFF11,
    EncodingLastRect = 0xFFFFFF20;

  final int HextileRaw			= (1 << 0);
  final int HextileBackgroundSpecified	= (1 << 1);
  final int HextileForegroundSpecified	= (1 << 2);
  final int HextileAnySubrects		= (1 << 3);
  final int HextileSubrectsColoured	= (1 << 4);

  final static int TightExplicitFilter  = 0x04;
  final static int TightFill            = 0x08;
  final static int TightMaxSubencoding  = 0x08;
  final static int TightFilterCopy      = 0x00;
  final static int TightFilterPalette   = 0x01;
  final static int TightFilterGradient  = 0x02;

  final static int TightMinToCompress   = 12;

  String host;
  int port;
  Socket sock;
  DataInputStream is;
  OutputStream os;
  boolean inNormalProtocol = false;
  vncviewer v;


  //
  // Constructor.  Just make TCP connection to RFB server.
  //

  rfbProto(String h, int p, vncviewer v1) throws IOException {
    v = v1;
    host = h;
    port = p;
    sock = new Socket(host, port);
    is = new DataInputStream(new BufferedInputStream(sock.getInputStream(),
						     16384));
    os = sock.getOutputStream();
  }


  void close() {
    try {
      sock.close();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  //
  // Read server's protocol version message
  //

  int serverMajor, serverMinor;

  void readVersionMsg() throws IOException {

    byte[] b = new byte[12];

    is.readFully(b);

    if ((b[0] != 'R') || (b[1] != 'F') || (b[2] != 'B') || (b[3] != ' ')
	|| (b[4] < '0') || (b[4] > '9') || (b[5] < '0') || (b[5] > '9')
	|| (b[6] < '0') || (b[6] > '9') || (b[7] != '.')
	|| (b[8] < '0') || (b[8] > '9') || (b[9] < '0') || (b[9] > '9')
	|| (b[10] < '0') || (b[10] > '9') || (b[11] != '\n'))
    {
      throw new IOException("Host " + host + " port " + port +
			    " is not an RFB server");
    }

    serverMajor = (b[4] - '0') * 100 + (b[5] - '0') * 10 + (b[6] - '0');
    serverMinor = (b[8] - '0') * 100 + (b[9] - '0') * 10 + (b[10] - '0');
  }


  //
  // Write our protocol version message
  //

  void writeVersionMsg() throws IOException {
    byte[] b = new byte[12];
    versionMsg.getBytes(0, 12, b, 0);
    os.write(b);
  }


  //
  // Find out the authentication scheme.
  //

  int readAuthScheme() throws IOException {
    int authScheme = is.readInt();

    switch (authScheme) {

    case ConnFailed:
      int reasonLen = is.readInt();
      byte[] reason = new byte[reasonLen];
      is.readFully(reason);
      throw new IOException(new String(reason, 0));

    case NoAuth:
    case VncAuth:
      return authScheme;

    default:
      throw new IOException("Unknown authentication scheme from RFB " +
			    "server " + authScheme);

    }
  }


  //
  // Write the client initialisation message
  //

  void writeClientInit() throws IOException {
    if (v.options.shareDesktop) {
      os.write(1);
    } else {
      os.write(0);
    }
    v.options.disableShareDesktop();
    v.options.disableViewOnly();
  }


  //
  // Read the server initialisation message
  //

  String desktopName;
  int framebufferWidth, framebufferHeight;
  int bitsPerPixel, depth;
  boolean bigEndian, trueColour;
  int redMax, greenMax, blueMax, redShift, greenShift, blueShift;

  void readServerInit() throws IOException {
    framebufferWidth = is.readUnsignedShort();
    framebufferHeight = is.readUnsignedShort();
    bitsPerPixel = is.readUnsignedByte();
    depth = is.readUnsignedByte();
    bigEndian = (is.readUnsignedByte() != 0);
    trueColour = (is.readUnsignedByte() != 0);
    redMax = is.readUnsignedShort();
    greenMax = is.readUnsignedShort();
    blueMax = is.readUnsignedShort();
    redShift = is.readUnsignedByte();
    greenShift = is.readUnsignedByte();
    blueShift = is.readUnsignedByte();
    byte[] pad = new byte[3];
    is.read(pad);
    int nameLength = is.readInt();
    byte[] name = new byte[nameLength];
    is.readFully(name);
    desktopName = new String(name, 0);

    inNormalProtocol = true;
  }


  //
  // Read the server message type
  //

  int readServerMessageType() throws IOException {
    return is.read();
  }


  //
  // Read a FramebufferUpdate message
  //

  int updateNRects;

  void readFramebufferUpdate() throws IOException {
    is.readByte();
    updateNRects = is.readUnsignedShort();
  }

  // Read a FramebufferUpdate rectangle header

  int updateRectX, updateRectY, updateRectW, updateRectH, updateRectEncoding;

  void readFramebufferUpdateRectHdr() throws IOException {
    updateRectX = is.readUnsignedShort();
    updateRectY = is.readUnsignedShort();
    updateRectW = is.readUnsignedShort();
    updateRectH = is.readUnsignedShort();
    updateRectEncoding = is.readInt();

    if ((updateRectX + updateRectW > framebufferWidth) ||
	(updateRectY + updateRectH > framebufferHeight)) {
      throw new IOException("Framebuffer update rectangle too large: " +
			    updateRectW + "x" + updateRectH + " at (" +
			    updateRectX + "," + updateRectY + ")");
    }
  }

  // Read CopyRect source X and Y.

  int copyRectSrcX, copyRectSrcY;

  void readCopyRect() throws IOException {
    copyRectSrcX = is.readUnsignedShort();
    copyRectSrcY = is.readUnsignedShort();
  }


  //
  // Read a ServerCutText message
  //

  String readServerCutText() throws IOException {
    byte[] pad = new byte[3];
    is.read(pad);
    int len = is.readInt();
    byte[] text = new byte[len];
    is.readFully(text);
    return new String(text, 0);
  }


  //
  // Read integer in compact representation
  //

  int readCompactLen() throws IOException {
    int portion = is.readUnsignedByte();
    int len = portion & 0x7F;
    if ((portion & 0x80) != 0) {
      portion = is.readUnsignedByte();
      len |= (portion & 0x7F) << 7;
      if ((portion & 0x80) != 0) {
	portion = is.readUnsignedByte();
	len |= (portion & 0xFF) << 14;
      }
    }
    return len;
  }


  //
  // Write a FramebufferUpdateRequest message
  //

  void writeFramebufferUpdateRequest(int x, int y, int w, int h,
				     boolean incremental)
       throws IOException
  {
    byte[] b = new byte[10];

    b[0] = (byte) FramebufferUpdateRequest;
    b[1] = (byte) (incremental ? 1 : 0);
    b[2] = (byte) ((x >> 8) & 0xff);
    b[3] = (byte) (x & 0xff);
    b[4] = (byte) ((y >> 8) & 0xff);
    b[5] = (byte) (y & 0xff);
    b[6] = (byte) ((w >> 8) & 0xff);
    b[7] = (byte) (w & 0xff);
    b[8] = (byte) ((h >> 8) & 0xff);
    b[9] = (byte) (h & 0xff);

    os.write(b);
  }


  //
  // Write a SetPixelFormat message
  //

  void writeSetPixelFormat(int bitsPerPixel, int depth, boolean bigEndian,
			   boolean trueColour,
			   int redMax, int greenMax, int blueMax,
			   int redShift, int greenShift, int blueShift)
       throws IOException
  {
    byte[] b = new byte[20];

    b[0]  = (byte) SetPixelFormat;
    b[4]  = (byte) bitsPerPixel;
    b[5]  = (byte) depth;
    b[6]  = (byte) (bigEndian ? 1 : 0);
    b[7]  = (byte) (trueColour ? 1 : 0);
    b[8]  = (byte) ((redMax >> 8) & 0xff);
    b[9]  = (byte) (redMax & 0xff);
    b[10] = (byte) ((greenMax >> 8) & 0xff);
    b[11] = (byte) (greenMax & 0xff);
    b[12] = (byte) ((blueMax >> 8) & 0xff);
    b[13] = (byte) (blueMax & 0xff);
    b[14] = (byte) redShift;
    b[15] = (byte) greenShift;
    b[16] = (byte) blueShift;

    os.write(b);
  }


  //
  // Write a FixColourMapEntries message.  The values in the red, green and
  // blue arrays are from 0 to 65535.
  //

  void writeFixColourMapEntries(int firstColour, int nColours,
				int[] red, int[] green, int[] blue)
       throws IOException
  {
    byte[] b = new byte[6 + nColours * 6];

    b[0] = (byte) FixColourMapEntries;
    b[2] = (byte) ((firstColour >> 8) & 0xff);
    b[3] = (byte) (firstColour & 0xff);
    b[4] = (byte) ((nColours >> 8) & 0xff);
    b[5] = (byte) (nColours & 0xff);

    for (int i = 0; i < nColours; i++) {
      b[6 + i * 6]     = (byte) ((red[i] >> 8) & 0xff);
      b[6 + i * 6 + 1] = (byte) (red[i] & 0xff);
      b[6 + i * 6 + 2] = (byte) ((green[i] >> 8) & 0xff);
      b[6 + i * 6 + 3] = (byte) (green[i] & 0xff);
      b[6 + i * 6 + 4] = (byte) ((blue[i] >> 8) & 0xff);
      b[6 + i * 6 + 5] = (byte) (blue[i] & 0xff);
    }
 
    os.write(b);
  }


  //
  // Write a SetEncodings message
  //

  void writeSetEncodings(int[] encs, int len) throws IOException {
    byte[] b = new byte[4 + 4 * len];

    b[0] = (byte) SetEncodings;
    b[2] = (byte) ((len >> 8) & 0xff);
    b[3] = (byte) (len & 0xff);

    for (int i = 0; i < len; i++) {
      b[4 + 4 * i] = (byte) ((encs[i] >> 24) & 0xff);
      b[5 + 4 * i] = (byte) ((encs[i] >> 16) & 0xff);
      b[6 + 4 * i] = (byte) ((encs[i] >> 8) & 0xff);
      b[7 + 4 * i] = (byte) (encs[i] & 0xff);
    }

    os.write(b);
  }


  //
  // Write a ClientCutText message
  //

  void writeClientCutText(String text) throws IOException {
    byte[] b = new byte[8 + text.length()];

    b[0] = (byte) ClientCutText;
    b[4] = (byte) ((text.length() >> 24) & 0xff);
    b[5] = (byte) ((text.length() >> 16) & 0xff);
    b[6] = (byte) ((text.length() >> 8) & 0xff);
    b[7] = (byte) (text.length() & 0xff);

    text.getBytes(0, text.length(), b, 8);

    os.write(b);
  }


  //
  // A buffer for putting pointer and keyboard events before being sent.  This
  // is to ensure that multiple RFB events generated from a single Java Event 
  // will all be sent in a single network packet.  The maximum possible
  // length is 4 modifier down events, a single key event followed by 4
  // modifier up events i.e. 9 key events or 72 bytes.
  //

  byte[] eventBuf = new byte[72];
  int eventBufLen;


  //
  // Write a pointer event message.  We may need to send modifier key events
  // around it to set the correct modifier state.  Also buttons 2 and 3 are
  // represented as having ALT and META modifiers respectively.
  //

  int pointerMask = 0;

  void writePointerEvent(Event evt)
       throws IOException
  {
    byte[] b = new byte[6];

    if (evt.id == Event.MOUSE_DOWN) {
      pointerMask = 1;
      if ((evt.modifiers & Event.ALT_MASK) != 0) {
	if (v.options.reverseMouseButtons2And3)
	  pointerMask = 4;
	else
	  pointerMask = 2;
      }
      if ((evt.modifiers & Event.META_MASK) != 0) {
	if (v.options.reverseMouseButtons2And3)
	  pointerMask = 2;
	else
	  pointerMask = 4;
      }
    } else if (evt.id == Event.MOUSE_UP) {
      pointerMask = 0;
    }

    evt.modifiers &= ~(Event.ALT_MASK|Event.META_MASK);

    eventBufLen = 0;

    writeModifierKeyEvents(evt.modifiers);

    if (evt.x < 0) evt.x = 0;
    if (evt.y < 0) evt.y = 0;

    eventBuf[eventBufLen++] = (byte) PointerEvent;
    eventBuf[eventBufLen++] = (byte) pointerMask;
    eventBuf[eventBufLen++] = (byte) ((evt.x >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (evt.x & 0xff);
    eventBuf[eventBufLen++] = (byte) ((evt.y >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (evt.y & 0xff);

    //
    // Always release all modifiers after an "up" event
    //

    if (pointerMask == 0) {
      writeModifierKeyEvents(0);
    }

    os.write(eventBuf, 0, eventBufLen);
  }


  //
  // Write a key event message.  We may need to send modifier key events
  // around it to set the correct modifier state.  Also we need to translate
  // from the Java key values to the X keysym values used by the RFB protocol.
  //

  void writeKeyEvent(Event evt)
       throws IOException
  {
    int key = evt.key;
    boolean down = false;

    if ((evt.id == Event.KEY_PRESS) || (evt.id == Event.KEY_ACTION))
      down = true;

    if ((evt.id == Event.KEY_ACTION) || (evt.id == Event.KEY_ACTION_RELEASE)) {

      //
      // A KEY_ACTION event should be one of the following.  If not then just
      // ignore the event.
      //

      switch(key) {
      case Event.HOME:	key = 0xff50; break;
      case Event.LEFT:	key = 0xff51; break;
      case Event.UP:	key = 0xff52; break;
      case Event.RIGHT:	key = 0xff53; break;
      case Event.DOWN:	key = 0xff54; break;
      case Event.PGUP:	key = 0xff55; break;
      case Event.PGDN:	key = 0xff56; break;
      case Event.END:	key = 0xff57; break;
      case Event.F1:	key = 0xffbe; break;
      case Event.F2:	key = 0xffbf; break;
      case Event.F3:	key = 0xffc0; break;
      case Event.F4:	key = 0xffc1; break;
      case Event.F5:	key = 0xffc2; break;
      case Event.F6:	key = 0xffc3; break;
      case Event.F7:	key = 0xffc4; break;
      case Event.F8:	key = 0xffc5; break;
      case Event.F9:	key = 0xffc6; break;
      case Event.F10:	key = 0xffc7; break;
      case Event.F11:	key = 0xffc8; break;
      case Event.F12:	key = 0xffc9; break;
      default:
        return;
      }

    } else {

      //
      // A "normal" key press.  Ordinary ASCII characters go straight through.
      // For CTRL-<letter>, CTRL is sent separately so just send <letter>.
      // Backspace, tab, return, escape and delete have special keysyms.
      // Anything else we ignore.
      //

      if (key < 32) {
	if ((evt.modifiers & Event.CTRL_MASK) != 0) {
	  key += 96;
	} else {
	  switch(key) {
	  case 8:  key = 0xff08; break;
	  case 9:  key = 0xff09; break;
	  case 10: key = 0xff0d; break;
	  case 27: key = 0xff1b; break;
	  }
	}
      } else if (key >= 127) {
	if (key == 127) {
	  key = 0xffff;
	} else {
	  // JDK1.1 on X incorrectly passes some keysyms straight through, so
	  // we do too.  JDK1.1.4 seems to have fixed this.
	  if ((key < 0xff00) || (key > 0xffff))
	    return;
	}
      }
    }

    eventBufLen = 0;

    writeModifierKeyEvents(evt.modifiers);

    writeKeyEvent(key, down);

    //
    // Always release all modifiers after an "up" event
    //

    if (!down) {
      writeModifierKeyEvents(0);
    }

    os.write(eventBuf, 0, eventBufLen);
  }


  //
  // Add a raw key event with the given X keysym to eventBuf.
  //

  void writeKeyEvent(int keysym, boolean down)
       throws IOException
  {
    eventBuf[eventBufLen++] = (byte) KeyEvent;
    eventBuf[eventBufLen++] = (byte) (down ? 1 : 0);
    eventBuf[eventBufLen++] = (byte) 0;
    eventBuf[eventBufLen++] = (byte) 0;
    eventBuf[eventBufLen++] = (byte) ((keysym >> 24) & 0xff);
    eventBuf[eventBufLen++] = (byte) ((keysym >> 16) & 0xff);
    eventBuf[eventBufLen++] = (byte) ((keysym >> 8) & 0xff);
    eventBuf[eventBufLen++] = (byte) (keysym & 0xff);
  }


  //
  // Write key events to set the correct modifier state.
  //

  int oldModifiers;

  void writeModifierKeyEvents(int newModifiers)
       throws IOException
  {
    if ((newModifiers & Event.CTRL_MASK) != (oldModifiers & Event.CTRL_MASK))
      writeKeyEvent(0xffe3, (newModifiers & Event.CTRL_MASK) != 0);

    if ((newModifiers & Event.SHIFT_MASK) != (oldModifiers & Event.SHIFT_MASK))
      writeKeyEvent(0xffe1, (newModifiers & Event.SHIFT_MASK) != 0);

    if ((newModifiers & Event.META_MASK) != (oldModifiers & Event.META_MASK))
      writeKeyEvent(0xffe7, (newModifiers & Event.META_MASK) != 0);

    if ((newModifiers & Event.ALT_MASK) != (oldModifiers & Event.ALT_MASK))
      writeKeyEvent(0xffe9, (newModifiers & Event.ALT_MASK) != 0);

    oldModifiers = newModifiers;
  }
}