#include <Wire.h>
#include <string.h>
#include <stdio.h>


uint8_t outbuf[6]; // array to store arduino output
char storebuf[200]; //array to store arduino input (transmitted from PC)
int cnt = 0;
int ledPin = 13;


void
receiveEvent (int howMany)
{

  while (Wire.available ())
    {
      int c = Wire.receive ();	// receive byte as an integer
      char myinput[10];
      sprintf (myinput, "%d", c); // convert integer to character
      strncat (storebuf, myinput, 10); // copy into the input buffer
      strncat (storebuf, ",", 1); // add a comma
      cnt++;
      // after we read 50 bytes, print what we have so far
      if (cnt > 50)
	{
	  print ();
	}
      digitalWrite (ledPin, HIGH);	// sets the LED on
    }
  strncat (storebuf, ":", 1);  // add a break after each set of input data
}

void
requestEvent ()
{
  // Send some data back to the wiimote to be transmitted back to PC
  outbuf[0] = nunchuk_encode_byte (125);	// joystick X
  outbuf[1] = nunchuk_encode_byte (126);	// joystick Y
  outbuf[2] = nunchuk_encode_byte (227);	// Axis X
  outbuf[3] = nunchuk_encode_byte (241);	// Axis Y
  outbuf[4] = nunchuk_encode_byte (140);	// Axis Z
  outbuf[5] = nunchuk_encode_byte (1);	// Press C button, byte[5] is buttons 
  //C,Z and accelaration data
  //outbuf[5] = nunchuk_encode_byte(2); // Press Z button
  //outbuf[5] = nunchuk_encode_byte(0); // Press Z and C button

  Wire.send (outbuf, 6);	// send data packet
}

void
setup ()
{
  beginSerial (19200);
  Serial.print ("Finished setup\n");
  Wire.begin (0x52);		// join i2c bus with address 0x52
  Wire.onReceive (receiveEvent);	// register event
  Wire.onRequest (requestEvent);	// register event
}


// Print the input data we have recieved
void
print ()
{
  int s = 0;

  Serial.println ("Start data dump");
  int a = strlen (storebuf); // Get the lenght of the buffer, then print it out one character at a time
  while (s < (a - 1))
    {
      Serial.print (storebuf[s]);
      s++;
    }

  cnt = 0;
  strcpy (storebuf, ""); // empty out the storage buffer
  Serial.println ("End data dump");
}

void
loop ()
{
  delay (100);
}

// Encode data to format that most wiimote drivers except
// only needed if you use one of the regular wiimote drivers
char
nunchuk_encode_byte (char x)
{
  x = x - 0x17;
  x = (x ^ 0x17);
  return x;
}