# imports
from machine import Pin
from machine import ADC
import math
import time

#pins
digits_pins = [11, 10, 9, 8]
segement_pins = [0, 1, 2, 3, 4, 5, 6]
digit_selector = []
segement_selector = []

dp = Pin(7, Pin.OUT)

#numbers as 0s and 1s 
num_segement_values = [
    [1, 1, 1, 1 ,1, 1, 0], #0
    [0, 1, 1, 0, 0, 0, 0], #1
    [1, 1, 0, 1, 1, 0, 1], #2
    [1, 1, 1, 1, 0, 0, 1], #3
    [0, 1, 1, 0, 0, 1, 1], #4
    [1, 0, 1, 1, 0, 1, 1], #5
    [1, 0, 1, 1, 1, 1, 1], #6
    [1, 1, 1, 0, 0, 0, 0], #7
    [1, 1, 1, 1, 1, 1, 1], #8
    [1, 1, 1, 1, 0, 1, 1]  #9
    ]

#for loops to assign digits and segment pins as output pins

for i in digits_pins:
    digit_selector.append(Pin(i, Pin.OUT))

for i in segement_pins:
    segement_selector.append(Pin(i, Pin.OUT))

#function to display numbers 

def num_display(num):
    for i in range(7):
        segement_selector[i].value(num_segement_values[num][i])

#functions to select the digit to be displayed

def all_digits_off():
    dp.value(0)
    digit_selector[0].value(1)
    digit_selector[1].value(1)
    digit_selector[2].value(1)
    digit_selector[3].value(1)

def digit_1():
    all_digits_off()
    dp.value(1)
    digit_selector[0].value(0)
    digit_selector[1].value(1)
    digit_selector[2].value(1)
    digit_selector[3].value(1)

def digit_2():
    all_digits_off()
    digit_selector[0].value(1)
    digit_selector[1].value(0)
    digit_selector[2].value(1)
    digit_selector[3].value(1)

def digit_3():
    all_digits_off()
    digit_selector[0].value(1)
    digit_selector[1].value(1)
    digit_selector[2].value(0)
    digit_selector[3].value(1)

def digit_4():
    all_digits_off()
    digit_selector[0].value(1)
    digit_selector[1].value(1)
    digit_selector[2].value(1)
    digit_selector[3].value(0)

#declare the button as output pin
button = Pin(16, Pin.IN, Pin.PULL_UP)
button_press = False

#button handler function
def handler(pin):
    global button_press
    button_press = True

button.irq(trigger= Pin.IRQ_FALLING, handler= handler)

volt_reader = ADC(26)

display_active = False

#main loop to read the voltage and display it
while True:

    if button_press == True:

        display_active = not display_active
        button_press = False

        volt_read = volt_reader.read_u16()
        volt_val = float((volt_read/(2**16-1))*3.3)
        four_digit_num = "{:.3f}".format(volt_val)
        num_1 = int(four_digit_num[0])
        num_2 = int(four_digit_num[2])
        num_3 = int(four_digit_num[3])
        num_4 = int(four_digit_num[4])
        print(four_digit_num)
        while display_active:
            all_digits_off()
            num_display(num_1)
            digit_1()
            all_digits_off()
            
            time.sleep(0.01)
            num_display(num_2)
            digit_2()
            all_digits_off()
            time.sleep(0.01)
            num_display(num_3)
            digit_3()
            all_digits_off()
            time.sleep(0.01)
            num_display(num_4)
            digit_4()
            all_digits_off()
            time.sleep(0.01)
            if button_press :
                display_active = False