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

#######################################
# Pin and constant definitions
#######################################
analoge=ADC(Pin(26))
SEVEN_SEGMENT_START_PIN = 0
DISPLAY_COUNT = 4
DECIMAL_PRECISION = 3

# HEX values for 7 segment display values
digit_list_hex = [
    0x40,  # 0
    0x79,  # 1
    0x24,  # 2
    0x30,  # 3
    0x19,  # 4
    0x12,  # 5
    0x02,  # 6
    0x78,  # 7
    0x00,  # 8
    0x10,  # 9
]


#######################################
# Global variables
#######################################
display_value = 0
pushed=None
last_time=0
voltages=[]
voltage=0
display_value = 0
segment_pins = []
display_select_pins = []
current_display_index = DISPLAY_COUNT -1 
display_timer = None
counter_timer = None

#######################################
# Function definitions
#######################################

# Function to read the ADC pin and
# to convert the digital value to a voltage level in the 0-3.3V range
# This function updates the value of the display_value global variable
def read_analogue_voltage(pin):
    global voltage,voltages,last_time,pushed,analoge
    if time.ticks_diff(time.ticks_ms(),last_time) > 200:
        last_time = time.ticks_ms()
        pushed=1
        if len(voltages)>16:
            voltages=[]
        for i in range(16):
            analoge_value=analoge.read_u16() 
            voltage=(analoge_value / 65535)*3.3# We can use the pin parameter if needed
            voltages.append(voltage)
        voltage=sum(voltages)/len(voltages)
        print(f"voltage :{int(voltage*1000)}mV")
# Function to disable timer that triggers scanning 7 segment displays
def disable_display_timer():
    global display_timer
    display_timer.deinit()
    pass

# Function to enable timer that triggers scanning 7 segment displays
def enable_display_timer():
    global display_timer
    display_timer.init(period=30, mode=machine.Timer.PERIODIC, callback=scan_display)
# Function to handle scanning 7 segment displays
# Display the value stored in the display_value global variable
# on available 7-segment displays
def scan_display(timer_int):
    global current_display_index,voltage

    # Extract the digit corresponding to the current display index
    digit = int((voltage*1000 // math.pow(10, current_display_index))) % 10
    ###stopped here
    display_digit(digit, current_display_index, current_display_index == DECIMAL_PRECISION and 0 != DECIMAL_PRECISION)

    current_display_index = (current_display_index - 1)
    if current_display_index < 0:
        current_display_index = DISPLAY_COUNT -1
    pass

# Function display the given value on the display with the specified index
# dp_enable specifies if the decimal pooint should be on or off
def display_digit(digit_value, digit_index, dp_enable=False):
    for pin in display_select_pins:
        pin.value(0)
    mask = digit_list_hex[digit_value]
    for i in range(7):  # 7 segments from A to G
        segment_pins[i].value((mask >> i) & 1)

    segment_pins[7].value(1 if dp_enable == False else 0)
    if digit_index == -1:
        for pin in display_select_pins:
            pin.value(1)
    elif 0 <= digit_index < DISPLAY_COUNT:
        display_select_pins[digit_index].value(1)
    pass    
#function to handle the interrupt
interrupt_pin = machine.Pin(16, machine.Pin.IN, machine.Pin.PULL_UP)
interrupt_pin.irq(trigger=machine.Pin.IRQ_FALLING, handler=read_analogue_voltage)
def display_value_test():
    global voltage

    disable_display_timer()
    current_display_index = 0

    for i in range(0, len(digit_list_hex)):
        display_digit(i, -1, i % 2 != 0)
        time.sleep(0.5)

    for i in range(0, len(digit_list_hex)):
        display_digit(i, DISPLAY_COUNT - 1 - (i % DISPLAY_COUNT), True)
        time.sleep(0.5)        

    display_digit(16, -1, False)
    enable_display_timer()

# Function to setup GPIO/ADC pins, timers and interrupts
def setup():
    global segment_pins, display_select_pins
    global display_timer, counter_timer
    # Set up display select pins
    for i in range(SEVEN_SEGMENT_START_PIN + 8, SEVEN_SEGMENT_START_PIN + 8 + DISPLAY_COUNT):
        pin = machine.Pin(i, machine.Pin.OUT)
        pin.value(0)
        display_select_pins.append(pin)
    
    # Set up seven segment pins
    for i in range(SEVEN_SEGMENT_START_PIN, SEVEN_SEGMENT_START_PIN + 8):
        pin = machine.Pin(i, machine.Pin.OUT)
        pin.value(1)
        segment_pins.append(pin)
    pass
    display_timer = machine.Timer()
    enable_display_timer()
        
if __name__ == '__main__':
    
    while 1:
        if pushed==1:
            setup()
            pushed=0
        sleep(.5)