#!/usr/bin/python

# Quick and dirty AmbientOrb code to scrape and report election results
# most of this code came from:
# http://www.exothermia.net/monkeys_and_robots/2008/11/03/code-to-scape-cnncom-election-results/#more-34

import serial
import urllib2
import re
import time
from optparse import OptionParser

SERIAL_PORT = "/dev/ttyUSB0"
BAUD = 9600
UPDATE = 600

class ElectionWon(Exception):
	pass

class CNN(object):
	def __init__(self):
		self.url = "http://www.cnn.com/ELECTION/2008/results/president/"

	def get(self):
		"""return the electoral balance
				(dpopular, delectoral), (rpopular, relectoral)
		"""
		u = urllib2.urlopen(self.url)
		for line in u.readlines():
			res = re.search(r'var CNN_NData=(.*?);', line)
			if res is not None:
				data = res.group(1)
				data = data.replace("true", "True")
				data = data.replace("false", "False")
				data = eval(data)

				d,r = None, None
				for candidate in data['P']['candidates']:
					if candidate['party'] == 'D':
						d = candidate['votes'], candidate['evotes']
						if candidate['winner']:
							raise ElectionWon("D")
					elif candidate['party'] == 'R':
						r = candidate['votes'], candidate['evotes']
						if candidate['winner']:
							raise ElectionWon("R")

		return d,r

def normalize(d,r, interval=0.5):
	"""normalize to
		-1 => democrat winning
		+1 => republican winning
		abs(1.0) is having "2*interval" higher percent than the other guy
	"""
	if d+r == 0: return 0.0
	rnorm = 2.0*(1.0*r/(d+r) - 0.5) / (2*interval)
	if rnorm > 1.0: rnorm = 1.0
	if rnorm < -1.0: rnorm = -1.0
	return rnorm

def calc_color(value):
	"""
	Assumes a normaized -1:1 range and returns 0000FF through FF0000
	Only manipulates the Red and Blue values
	-1 ==> 0000FF
	 0 ==> 000000
	 1 ==> FF0000
	"""
	red = 0
	blue = 0
	
	if(value < 0):
		blue = (value * -128) + 127
	if(value > 0):
		red = (value * 128) + 127
	
	return('%02x00%02x' % (red, blue))

if __name__=='__main__':
	POP_VOTE = 0
	ELECTORAL_VOTE = 1

	parser = OptionParser()
	parser.add_option("-e", "--electoral", dest="vote_sel", action="store_const",
		const=ELECTORAL_VOTE, help="Report based on electoral vote (default)")
	parser.add_option("-p", "--popular", dest="vote_sel", action="store_const",
		const=POP_VOTE, help="Report based on popular vote")

	(options, args) = parser.parse_args()

	vote_sel = options.vote_sel
	if(vote_sel is None):
		vote_sel = ELECTORAL_VOTE

	cnn = CNN()
	ser = serial.Serial(SERIAL_PORT, BAUD, timeout=1)
	time.sleep(10)
	try:
		while True:
			(d,r) = cnn.get()
			ser.write("#" + calc_color(normalize(d[vote_sel], r[vote_sel])))
			time.sleep(UPDATE)
	except ElectionWon, elewon:
		if(elewon.message == 'D'):
			ser.write("%0000FF")
		elif(elewon.message == 'R'):
			ser.write("%FF0000")
	
	while True:
		time.sleep(UPDATE)