#!/usr/bin/env python3
# rpi_ws281x library strandtest example
# Initial author: Tony DiCola (tony@tonydicola.com)
# Author: Damien Broqua (contact@darkou.fr)

import time
from rpi_ws281x import *
import argparse
import RPi.GPIO as GPIO

# LED strip configuration:
LED_COUNT       = 60      # Number of LED pixels.
LED_PIN         = 18      # GPIO pin connected to the pixels (18 uses PWM!).
LED_FREQ_HZ     = 800000  # LED signal frequency in hertz (usually 800khz)
LED_DMA         = 10      # DMA channel to use for generating signal (try 10)
LED_BRIGHTNESS  = 255     # Set to 0 for darkest and 255 for brightest
LED_INVERT      = False   # True to invert the signal (when using NPN transistor level shift)
LED_CHANNEL     = 0       # set to '1' for GPIOs 13, 19, 41, 45 or 53

LED_DISPLAY     = True
BUTTON          = 16


def handlePushButton(button):
    global LED_DISPLAY
    LED_DISPLAY = not LED_DISPLAY
    print ('Pushed !')

# Define functions which animate LEDs in various ways.
def colorWipe(strip, color, wait_ms=50):
    """Wipe color across display a pixel at a time."""
    for i in range(strip.numPixels()):
        strip.setPixelColor(i, color)
        strip.show()
        time.sleep(wait_ms/1000.0)

def wheel(pos):
    """Generate rainbow colors across 0-255 positions."""
    if pos < 85:
        return Color(pos * 3, 255 - pos * 3, 0)
    elif pos < 170:
        pos -= 85
        return Color(255 - pos * 3, 0, pos * 3)
    else:
        pos -= 170
        return Color(0, pos * 3, 255 - pos * 3)

def rainbowCycle(strip, wait_ms=20, iterations=5):
    """Draw rainbow that uniformly distributes itself across all pixels."""
    for j in range(256*iterations):
        for i in range(strip.numPixels()):
            strip.setPixelColor(i, wheel((int(i * 256 / strip.numPixels()) + j) & 255))
            if LED_DISPLAY == False:
                break
        strip.show()
        time.sleep(wait_ms/1000.0)
        if LED_DISPLAY == False:
            break

# Main program logic follows:
if __name__ == '__main__':
    global BUTTON
    # Process arguments
    parser = argparse.ArgumentParser()
    parser.add_argument('-c', '--clear', action='store_true', help='clear the display on exit')
    args = parser.parse_args()

    # Create NeoPixel object with appropriate configuration.
    strip = Adafruit_NeoPixel(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, LED_BRIGHTNESS, LED_CHANNEL)
    # Intialize the library (must be called once before other functions).
    strip.begin()

    GPIO.setmode(GPIO.BOARD)
    GPIO.setup(BUTTON, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
    GPIO.add_event_detect(BUTTON, GPIO.FALLING, callback=handlePushButton, bouncetime=250)

    print ('Press Ctrl-C to quit.')
    if not args.clear:
        print('Use "-c" argument to clear LEDs on exit')

    try:

        while True:
            if LED_DISPLAY == True:
                rainbowCycle(strip)
            else:
                colorWipe(strip, Color(0,0,0), 10)

    except KeyboardInterrupt:
        if args.clear:
            print("Done")
            colorWipe(strip, Color(0,0,0), 10)