import machine
import time

DISPLAY_COUNT ,DECIMAL_PRECISION ,DEBOUNCE_TIME,READINGS_COUNT = 4,1,200,16
VOLTAGE_REFERENCE ,ADC_RESOLUTION = 3.3,65535

display_value ,last_button_press_time,timer = 0,0,None

digit_list_hex = [0x40, 0x79,0x24,0x30,0x19,0x12,0x02,0x78,0x00,0x10]

segment_pins ,display_select_pins ,Analog ,button = [],[],None,None




def read_sensor_voltage():
    return ((Analog.read_u16()) * VOLTAGE_REFERENCE / ADC_RESOLUTION)


def scan_display(timer):
    global display_value
    # Convert the display_value to a string
    value_str = "{:.3f}".format(display_value)

    # Remove the decimal point and get the first 4 digits
    value_str = value_str.replace('.', '')[:4]

    # Create a list of digits with leading zeros if necessary
    digits = [int(value_str[i]) if i < len(value_str) else 0 for i in range(DISPLAY_COUNT)]

    # Determine if the decimal point should be enabled
    dp_enable = (digits[0] != 0)

    # Display the digits on the corresponding 7-segment displays
    for i, digit in enumerate(digits):
        display_digit(digit, i, dp_enable)

def display_digit(digit_value, digit_index, dp_enable=False):
    # Ensure the value is valid
    if 0 <= digit_value < len(digit_list_hex):
        # Deselect all display select pins
        for pin in display_select_pins:
            pin.value(0)

        # Set the segments according to the digit value
        mask = digit_list_hex[digit_value]
        for i, pin in enumerate(segment_pins):
            pin.value((mask >> i) & 1)

        # Set the DP if it's enabled
        segment_pins[7].value(int(not dp_enable))

        # Activate the relevant display select pin
        display_select_pins[digit_index].value(1) if 0 <= digit_index < DISPLAY_COUNT else None

def enable_display_timer():
    global timer
    timer = machine.Timer()
    timer.init(period=1, mode=machine.Timer.PERIODIC, callback=scan_display)

def read_analogue_voltage(pin):
    global display_value, last_button_press_time
    current_time = time.ticks_ms()

    # Debouncing the button
    if current_time - last_button_press_time > DEBOUNCE_TIME:
        last_button_press_time = current_time
        display_value = read_sensor_voltage()
        # Print the voltage on the serial
        print("Voltage: {:.0f} mV".format(display_value * 1000))

def setup():
    global segment_pins, display_select_pins, Analog, button
    # Define pins for the segments and displays
    pin_numbers = [0, 1, 2, 3, 4, 5, 6, 7, 11, 10, 9, 8]
    segment_pins = [machine.Pin(pin_number, machine.Pin.OUT) for pin_number in pin_numbers[:8]]
    display_select_pins = [machine.Pin(pin_number, machine.Pin.OUT) for pin_number in pin_numbers[8:]]

    # Initialize ADC for analog reading
    Analog = machine.ADC(26)

    # Initialize button with interrupt for analog reading
    button = machine.Pin(16, machine.Pin.IN)
    button.irq(trigger=machine.Pin.IRQ_FALLING, handler=read_analogue_voltage)

    # Enable the display timer
    enable_display_timer()

if __name__ == '__main__':
    setup()