#!/bin/env python

import serial
import pygame


def compute_value(line, minimum, maximum):
    line = line.split(" ")
    if len(line) < 3:
        return False

    for i in range(3):
        value[i] = int(255*(line[i]-minimum[i])/(maximum[i]-minimum[i]))
        if value[i] > 255:
            value[i] = 255
        elif value[i] < 0:
            value[i] = 0

    return value[0], value[1], value[2]


ser = serial.Serial("/dev/ttyACM0", 115200)
pygame.init()

size = width, height = 640, 480
screen = pygame.display.set_mode(size)
pygame.display.set_caption("Touchless 3D tracking")
screen.fill((0, 0, 0))

try:
    ser.open()
except Exception as e:
    print("Error while opening serial port : "+str(e))

if ser.isOpen():
    try:
        ser.flushInput()
        ser.flushOutput()

        maximum = [-1, -1, -1]
        minimum = [-1, -1, -1]

        print("Calibration :")
        pygame.display.flip()

        for i in range(50):
            line = float(ser.readline())

            if line < minimum or minimum < 0:
                minimumR = line
            if line > maximum:
                maximumR = line

        print("Go :")
        running = True
        while running:
            # Quit if window is closed
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    running = False

            # Read line from serial
            line = float(ser.readline())
            # Compute the value for red
            value = compute_value(line, minimum, maximum)

            if value is not False:
                screen.fill(value)
                pygame.display.flip()

        ser.close()
    except Exception as e:
        print("Error while fetching data from serial : "+str(e))