import board
import neopixel
import time
from analogio import AnalogIn
import array

n_pixels    = 10            # Number of pixels you are using
dc_offset   = 0             # DC offset in mic signal - if unusure, leave 0
noise       = 100           # Noise/hum/interference in mic signal
lvl         = 10            # Current "dampened" audio level
maxbrt    = 127             # Maximum brightness of the neopixels (0-255)
wheelStart  = 0             # Start of the RGB spectrum we'll use
wheelEnd    = 255           # End of the RGB spectrum we'll use

mic_pin = AnalogIn(board.A7)

# Set up NeoPixels and turn them all off.
strip = neopixel.NeoPixel(board.NEOPIXEL, n_pixels, brightness=0.1, auto_write=False)
strip.fill(0)
strip.show()

def wheel(pos):
    # Input a value 0 to 255 to get a color value.
    # The colours are a transition r - g - b - back to r.
    if (pos < 0) or (pos > 255):
        return (0, 0, 0)
    if (pos < 85):
        return (int(pos * 3), int(255 - (pos*3)), 0)
    elif (pos < 170):
        pos -= 85
        return (int(255 - pos*3), 0, int(pos*3))
    else:
        pos -= 170
        return (0, int(pos*3), int(255 - pos*3))
    
def remapRangeSafe(value, leftMin, leftMax, rightMin, rightMax):
    # this remaps a value from original (left) range to new (right) range
    
    # Force the input value to within left min & max
    if value < leftMin: value = leftMin
    if value > leftMax: value = leftMax
    
    # Figure out how 'wide' each range is
    leftSpan = leftMax - leftMin
    rightSpan = rightMax - rightMin

    # Convert the left range into a 0-1 range (int)
    valueScaled = int(value - leftMin) / int(leftSpan)

    # Convert the 0-1 range into a value in the right range.
    return int(rightMin + (valueScaled * rightSpan))

while True:
    n = int ( ( mic_pin.value / 65536 ) * 1000 )    # 10-bit ADC format
    n = abs(n - 512 - dc_offset)                    # Center on zero                   

    if ( n >= noise ):                              # Remove noise/hum
        n = n - noise       

    lvl = int ( ( (lvl * 7) + n ) / 8 )             # "Dampened" reading (else looks twitchy) - divide by 8 (2^3)
    
    # Color pixels based on rainbow gradient
    vlvl = remapRangeSafe(lvl, 0, 255, wheelStart, wheelEnd)
    for i in range(0, len(strip)):
        strip[i] = wheel(vlvl)
        # Set strip brightness based on audio level
        strip.brightness = float(remapRangeSafe(lvl,50,255,0,maxbrt))/255.0
    strip.show()