package acroname;
import java.io.*;

public class Brainstem
    {
    /** The input stream */
    public NonBlockingInputStream in;
    
    /** The output stream */
    public OutputStream out;
    byte[] buf = new byte[32];
    
    public static final int FAIL = -1024;
    public boolean time = false;
    long l;
    
    /** Make a Brainstem object. */
    public Brainstem()
        {
        try
            {
            in = new NonBlockingInputStream(new FileInputStream("/dev/brainstem")); 
            out = new FileOutputStream("/dev/brainstem");
            }
        catch (IOException e) { throw new RuntimeException("couldn't open /dev/brainstem"); }
        }
    
    public int setServo(int brainstemid, int servo, int position)
        {
        try
            {
            if (time) l = System.currentTimeMillis();
            byte[] packet = new byte[] { (byte)brainstemid, 3, 33, (byte)servo, (byte) position };
            out.write(packet);
            if (time) System.out.println("Time: " + (System.currentTimeMillis() - l));
            return 1;
            }
        catch (IOException e) { return FAIL; }
        }
    
    public int getA2D(int brainstemid, int sensor)
        {
        try
            {
            if (time) l = System.currentTimeMillis();
            byte[] packet = new byte[] { (byte)brainstemid, 2, 25, (byte)(sensor+128) };
            out.write(packet);
            
            int size =in.readNonBlocking(buf,1000);
            if (time) System.out.println("Time: " + (System.currentTimeMillis() - l));
            if (size <= 0) return FAIL;
            else return 256 * 
                (buf[size-2] < 0 ? 
                    buf[size-2] + 256 :
                    buf[size-2] )
                +
                (buf[size-1] < 0 ? 
                    buf[size-1] + 256 :
                    buf[size-1] );
            }
        catch (IOException e) { return FAIL; }
        }
        
    public int getDigital(int brainstemid, int sensor)
        {
        try
            {
            if (time) l = System.currentTimeMillis();
            byte[] packet = new byte[] { (byte)brainstemid, 2, 27, (byte)(sensor+128) };
            out.write(packet);
            
            int size =in.readNonBlocking(buf,1000);
            if (time) System.out.println("Time: " + (System.currentTimeMillis() - l));
            if (size <= 0) return FAIL;
            else return buf[size-1];
            }
        catch (IOException e) { return FAIL; }
        }
    
    public int getCharScratchpad(int brainstemid, int pad)
        {
        try
            {
            if (time) l = System.currentTimeMillis();
    //        if (pad > 31)  throw an error!
            byte[] packet = new byte[] { (byte)brainstemid, 2, 51, (byte)pad };
            out.write(packet);
            
            int size =in.readNonBlocking(buf,1000);
            if (time) System.out.println("Time: " + (System.currentTimeMillis() - l));
            if (size <= 0) return FAIL;
            else return buf[size-1];
            }
        catch (IOException e) { return FAIL; }
        }
    
    public int getIntScratchpad(int brainstemid, int pad)
        {
        int val0 = getCharScratchpad(brainstemid, pad);
        if (val0 == FAIL) return FAIL;
        int val1 = getCharScratchpad(brainstemid, pad+1);
        if (val1 == FAIL) return FAIL;
        byte b0 = (byte)val0;
        byte b1 = (byte)val1;
        return (short)((b0 << 8) + b1);
        }
    
    public int setCharScratchpad(int brainstemid, int pad, int value)
        {
        try
            {
            if (time) l = System.currentTimeMillis();
            byte[] packet = new byte[] { (byte)brainstemid, 3, 51, (byte)pad, (byte)value};
            //        if (pad > 31)  throw an error!
            out.write(packet);
            if (time) System.out.println("Time: " + (System.currentTimeMillis() - l));
            return 1;
            }
        catch (IOException e) { return FAIL; }
        }
    
    public int setIntScratchpad(int brainstemid, int pad, int value)
        {
        short sval = (short)value;
        if (setCharScratchpad(brainstemid, pad, sval & 0xFF00) == FAIL) return FAIL;
        if (setCharScratchpad(brainstemid, pad+1, sval & 0x00FF) == FAIL) return FAIL;
        return 1;
        }
    }