FingerReader.java :  » MIDI » fingerplaymidi » com » flat20 » fingerplay » socket » commands » Android Open Source

package com.flat20.fingerplay.socket.commands;

import java.io.DataInputStream;
import java.io.IOException;
import java.net.SocketException;

import com.flat20.fingerplay.socket.commands.midi.MidiSocketCommand;
import com.flat20.fingerplay.socket.commands.misc.DeviceList;
import com.flat20.fingerplay.socket.commands.misc.RequestMidiDeviceList;
import com.flat20.fingerplay.socket.commands.misc.SetMidiDevice;
import com.flat20.fingerplay.socket.commands.misc.Version;

public class FingerReader {

  final private DataInputStream mIn;
  final private IReceiver mReceiver;

  final private static byte[] sData = new byte[ 0xFFFF ];

  final private MidiSocketCommand sMss = new MidiSocketCommand();

  final private DeviceList sDl = new DeviceList();
  final private RequestMidiDeviceList sRmdl = new RequestMidiDeviceList();
  final private SetMidiDevice sMd = new SetMidiDevice();
  final private Version sV = new Version();

  public FingerReader(DataInputStream in, IReceiver receiver) {
    mIn = in;
    mReceiver = receiver;
  }

  public byte readCommand() throws Exception {

    byte command = mIn.readByte();

    // commands[COMMAND_ID] = SocketCommand ?
    switch (command) {
      case SocketCommand.COMMAND_MIDI_SHORT_MESSAGE:
        mReceiver.onMidiSocketCommand( decode(sMss, command) );
        return command;
      
      case SocketCommand.COMMAND_REQUEST_MIDI_DEVICE_LIST:
        mReceiver.onRequestMidiDeviceList( (RequestMidiDeviceList) decode(sRmdl, command) );
        return command;
      
      case SocketCommand.COMMAND_MIDI_DEVICE_LIST:
        mReceiver.onDeviceList( (DeviceList) decode(sDl, command) );
        return command;
      
      case SocketCommand.COMMAND_SET_MIDI_DEVICE:
        mReceiver.onSetMidiDevice( (SetMidiDevice) decode(sMd, command) );
        return command;

      case SocketCommand.COMMAND_VERSION:
        mReceiver.onVersion( (Version) decode(sV, command) );
        return command;
      default:
        System.out.println("Unknown command: " + command);
    }
    return -1;
  }

  private SocketCommand decode(SocketCommand socketCommand, byte command) {
    socketCommand.command = command;
    return socketCommand;
  }

  private void decode(SocketStringCommand socketCommand, byte command, int length, byte[] message) {
    socketCommand.command = command;
    socketCommand.message = new String(message, 0, length);
  }

  private SocketStringCommand decode(SocketStringCommand socketCommand, byte command) throws Exception {
    try {
      final DataInputStream in = mIn;
      // Read until we have an int.
      final int textLength = in.readInt(); // wait forever?
      if (textLength == -1)
        throw new SocketException("Disconnected");

      //byte[] data = new byte[textLength];
      final int numRead = in.read(sData, 0, textLength); // wait forever?
      if (numRead == -1)
        throw new SocketException("Disconnected");

      if (numRead != textLength)
        throw new Exception("Incorrect length for SocketStringCommand " + socketCommand.command);

      decode(socketCommand, command, textLength, sData);

      return socketCommand;

    } catch (IOException e) {
      throw new Exception("Couldn't parse SocketStringCommand " + socketCommand.command);
    }
  }

  private Version decode(Version version, byte command) throws Exception {
    decode((SocketStringCommand) version, command);
    return version;
  }

  private MidiSocketCommand decode(MidiSocketCommand socketCommand, byte command) throws Exception {
    try {
      final DataInputStream in = mIn;
      socketCommand.command = command;
      socketCommand.set(in.readByte(), in.readByte(), in.readByte(), in.readByte());
      return socketCommand;
    } catch (IOException e) {
      throw new Exception("Couldn't parse MidiSocketCommand " + socketCommand.command);
    }
  }


  public interface IReceiver {
    public void onMidiSocketCommand(MidiSocketCommand socketCommand) throws Exception;
    public void onRequestMidiDeviceList(RequestMidiDeviceList socketCommand) throws Exception;
    public void onDeviceList(DeviceList socketCommand) throws Exception;
    public void onSetMidiDevice(SetMidiDevice socketCommand) throws Exception;
    public void onVersion(Version socketCommand) throws Exception;
  }

}