import time
import serial
import random
from PIL import Image
import os

class PixelCounter(object):
  ''' loop through each pixel and average rgb '''
  def __init__(self, imageName):
      self.pic = Image.open(imageName)
      # load image data
      self.imgData = self.pic.load()
  def averagePixels(self):
      r, g, b = 0, 0, 0
      count = 0
      for x in xrange(self.pic.size[0]):
          for y in xrange(self.pic.size[1]):
              tempr,tempg,tempb = self.imgData[x,y]
              r += tempr
              g += tempg
              b += tempb
              count += 1
      # calculate averages
      return (r/count), (g/count), (b/count), count


# configure the serial connections (the parameters differs on the device you are connecting to)
ser = serial.Serial(
	port='/dev/tty.usbmodem411',
	baudrate=9600,
	parity=serial.PARITY_NONE,
	stopbits=serial.STOPBITS_ONE,
	bytesize=serial.EIGHTBITS
)

ser.open()

# Check we opened the port correctly
if not (ser.isOpen()):
	print "Failed to open the serial port"
	exit(1)

# Initialise all variables
input=1
r=128
b=128
g=128

# Loop forever
while 1 :
	# Monitor the serial connection
	if not (ser.isOpen()):
		print "The connection to the device was closed"
		exit(1)

	os.system("screencapture 1.jpg")
  	pc = PixelCounter('1.jpg')
	colourvals=pc.averagePixels()
	r=colourvals[0]

	# Construct the string
	string = 'w0-' + "%03d" % r
	string += '-' + "%03d" % g
	string += '-' + "%03d" % b
	print "Sending command: " + string


	# Append a carriage return and newline
	string += '\r\n'

	# Write the string to the serial port
	ser.write(string)
	time.sleep(0.1)

	# Increment values and handle variable overflow
	# r += 1
	# b += 1
	# g += 1
	#if b>254:b=128
	#if g>254:g=128
	#if r>254:r=128


	# Wait a little bit
	time.sleep(0.1)