Python source code for macOS task-complete notifier project

statuslight.py

#!/usr/bin/env python

import time
import sys
import os
import Adafruit_GPIO as GPIO
import Adafruit_GPIO.FT232H as FT232H

# This class code derivaes from Adafruit's tutorial
# at https://learn.adafruit.com/adafruit-ft232h-breakout
# I had to up the SPI speed to 75MHz to work
# cu.usbserial-141

class NeoPixel_FT232H(object):
    def __init__(self, n):
        self.ft232h = FT232H.FT232H()
        self.spi = FT232H.SPI(self.ft232h, max_speed_hz=7500000, mode=0, bitorder=FT232H.MSBFIRST)
        self.buffer = bytearray(n * 24)
        self.lookup = self.build_byte_lookup()

    def build_byte_lookup(self):
        lookup = {}
        for i in range(256):
            value = bytearray()
            for j in range(7, -1, -1):
                if ((i >> j) & 1) == 0:
                    value.append(0b11100000)
                else:
                    value.append(0b11111000)
            lookup[i] = value
        return lookup

    def set_pixel_color(self, n, r, g, b):
        # Set the pixel RGB color for the pixel at position n.
        index = n * 24
        self.buffer[index :index+8 ] = self.lookup[int(g)]
        self.buffer[index+8 :index+16] = self.lookup[int(r)]
        self.buffer[index+16 :index+24] = self.lookup[int(b)]

    def show(self):
        # Send the pixel buffer out the SPI data output pin (D1)
        self.spi.write(self.buffer)

# START

if __name__ == '__main__':
    FT232H.use_FT232H()

    pixel_count = 1
    pixels = NeoPixel_FT232H(pixel_count)

    filename = '/Users/smittytone/.status' # Enter your own path here
    brightness = 30 # Brightness control as a percentage
    delay = 0.1

    redVal = 252
    greenVal = 0
    blueVal = 0

    redDel = 2
    greenDel = 2
    blueDel = 2

    redOn = True
    greenOn = False
    blueOn = False

    saveRed = 252
    saveGreen = 0
    saveBlue = 0

    noteOne = False

    print 'Ctrl-C to quit'

    while True:
        try:
            pixels.set_pixel_color(0, (redVal * brightness / 100), (greenVal * brightness / 100), (blueVal * brightness / 100))
            pixels.show()

            if noteOne:
                # Notification flag set
                if redVal != 0:
                    redVal = 0
                else:
                    redVal = 255
            else:
                # Notification flag unset; run a colour sweep effect
                if redOn:
                    redVal = redVal + redDel
                    if redVal > 254:
                        redVal = 254
                        redDel = -2
                        greenOn = True

                    if redVal < 1:
                        redDel = 2
                        redOn = False
                        redVal = 0

                if greenOn:
                    greenVal = greenVal + greenDel
                    if greenVal > 254:
                        greenDel = -2
                        blueOn = True
                        greenVal = 254

                    if greenVal < 1:
                        greenDel = 2
                        greenOn = False
                        greenVal = 0

                if blueOn:
                    blueVal = blueVal + blueDel
                    if blueVal > 254:
                        blueDel = -1
                        redOn = True
                        blueVal = 254

                    if blueVal < 1:
                        blueDel = 2
                        blueOn = False
                        blueVal = 0

            # Check file
            if os.path.exists(filename):
                file = open(filename)
                text = file.read()
                file.close()
                # File contains three values, eg. 0.0.0
                # First is a marker for the red light (1 = on; 0 = off)
                items = text.split('.')
                if items[0] != '0':
                    # Status file indicates notification light should be on
                    if noteOne == False:
                        # So turn it on only if it's currently off
                        noteOne = True
                        saveGreen = greenVal
                        greenVal = 0
                        saveRed = redVal
                        redVal = 255
                        saveBlue = blueVal
                        blueVal = 0
                        delay = 0.5
                else:
                    # Disable the notification...
                    if noteOne:
                        # ...but only if it's actually on
                        noteOne = False
                        redVal = saveRed
                        greenVal = saveGreen
                        blueVal = saveBlue
                        delay = 0.1
            else:
                # No file error - warn the user
                print 'No status file'
                noteOne = False
                redVal = saveRed
                greenVal = saveGreen
                blueVal = saveBlue
                delay = 0.1

            time.sleep(delay)
        except KeyboardInterrupt:
            for i in range(pixel_count):
                pixels.set_pixel_color(0, 0, 0, 0)
            pixels.show()
sys.exit(-1)