import os, machine, time, neopixel, micropython

micropython.alloc_emergency_exception_buf(100)

# how many LEDs are there in a row?
Nled = 16

# define pin for led control
# see reference for GPIO numbers: https://microcontrollerslab.com/wp-content/uploads/2019/05/ESP8266-12E-Wemos-D1-Mini-pinout.jpg
# not all GPIO pins can be used ...
pin_number = 5
neopin = machine.Pin(pin_number, machine.Pin.OUT)
# initialize neopixel object to write to
np = neopixel.NeoPixel(neopin, Nled)

# define pin for button
button = machine.Pin(13, machine.Pin.IN)

# variable and function for button handling
button_pressed = False
def handle_button(pin):
    global button_pressed
    button_pressed = True
    time.sleep_ms(200)

# register button function for interrupt
button.irq(trigger=machine.Pin.IRQ_RISING, handler=handle_button)

# define ranges of LEDs
full = range(0, Nled)

# define colors for LEDs
red = (255, 0, 0)
green = (0, 255, 0)
blue = (0, 0, 255)
orange = (220, 35, 0)
purple = (255, 0, 255)
white = (255, 255, 255)
off = (0, 0, 0)

# color the leds
def paint(color = white, section = full, single = False):
    if single:
        section = [section]
    for i in section:
        if i not in full:
            i %= Nled
        np[i] = color
    np.write()

# get rainbow colors
# Input a value 0 to 255 to get a color value.
# The colours are a transition r - g - b - back to r.
def wheel(pos):
    
    if pos < 0 or pos > 255:
        return (0, 0, 0)
    if pos < 85:
        return (255 - pos * 3, pos * 3, 0)
    if pos < 170:
        pos -= 85
        return (0, 255 - pos * 3, pos * 3)
    pos -= 170
    return (pos * 3, 0, 255 - pos * 3)

# cycle rainbow colors
def rainbow_cycle(wait):
    global button_pressed
    n = Nled
    while not button_pressed:
        for j in range(255):
            for i in range(n):
                rc_index = (i * 256 // n) + j
                np[i] = wheel(rc_index & 255)
            np.write()
            if button_pressed:
                break
            time.sleep_ms(wait)
    button_pressed = False

# pulsating rainbow
def solid_rainbow(wait):
    global button_pressed
    while not button_pressed:
        for j in range(255):
            paint(wheel(j))
            if button_pressed:
                break
            time.sleep_ms(wait)
    button_pressed = False

# just a single color
def solid_color(color):
    global button_pressed
    paint(color)
    while not button_pressed:
        time.sleep_ms(100)
    button_pressed = False

# single led rotating
def chase_single(color, wait):
    global button_pressed
    while not button_pressed:
        for i in full:
            paint(color, i, True)
            paint(off, i - 1, True)
            if button_pressed:
                break
            time.sleep_ms(wait)
    button_pressed = False

while True:
    rainbow_cycle(5)
    solid_rainbow(200)
    chase_single(orange, 50)
    chase_single(white, 50)
    chase_single(purple, 50)
    solid_color(red)
    solid_color(green)
    solid_color(blue)