from machine import SPI, ADC, Pin
import time
from utime import sleep
import math
print(1)
light = ADC(Pin(26))
iso = 90
gamma = 0.7
rl10 = 50
max_value = 65535
f_stop = 8.0
print_button = machine.Pin(17, machine.Pin.IN, machine.Pin.PULL_UP)
read_button = machine.Pin(27, machine.Pin.IN, machine.Pin.PULL_UP)
serial = SPI(0, 10000000, sck=Pin(2,Pin.OUT), mosi=Pin(3,Pin.OUT))
latch = Pin(1, Pin.OUT)

# gradeColors = [ {'R': 1, 'G': 0.97, 'B': 0.325, 'Grade': '00'}, {'R': 1, 'G': 0.94, 'B': 0.475, 'Grade': '0'}, {'R': 1, 'G': 0.945, 'B': 0.615, 'Grade': '0.5'}, {'R': 1, 'G': 0.915, 'B': 0.665, 'Grade': '1'}, {'R': 1, 'G': 0.86, 'B': 0.74, 'Grade': '1.5'}, {'R': 1, 'G': 0.785, 'B': 0.805, 'Grade': '2'}, {'R': 1, 'G': 0.745, 'B': 0.84, 'Grade': '2.5'}, {'R': 1, 'G': 0.69, 'B': 0.885, 'Grade': '3'}, {'R': 1, 'G': 0.605, 'B': 0.93, 'Grade': '3.5'}, {'R': 1, 'G': 0.525, 'B': 0.95, 'Grade': '4'}, {'R': 1, 'G': 0.23, 'B': 0.925, 'Grade': '4.5'}, {'R': 1, 'G': 0, 'B': 1, 'Grade': '5'} ]

def calculate_lux(analogValue):
    voltage = analogValue / max_value * 5
    resistance = 2000 * voltage / (1 - voltage / 5)
    return math.pow(rl10 * 1000 * math.pow(10, gamma) / resistance, (1 / gamma))

def calculate_ev_iso_100(lux):
    return math.log2(lux / 2.5)
    
def iso_stops(iso):
    return math.log2(iso/100)

def ev_to_seconds(ev):
    return (100 * f_stop**2)/(100 * 2**ev)

led = Pin(9, Pin.OUT)
highlight_value = 7
middle_value = 5
seconds = 0

while True:
    if read_button.value() == 0:
        analogValue = light.read_u16()
        lux = calculate_lux(analogValue)
        ev_iso_100 = calculate_ev_iso_100(lux)
        stops_off = iso_stops(iso)
        seconds = ev_to_seconds(ev_iso_100 + stops_off + (highlight_value - middle_value))
        print(lux)
        print(seconds)
        sleep(0.1)
        
    if print_button.value() == 0:
        led.on()
        sleep(seconds)
        led.off()
    
    latch.off()
    serial.write(b"0b10110111")
    latch.on()
    
    sleep(0.5)