from machine import Pin, I2C
from utime import sleep

# Initialize I2C on GP0 (SDA) and GP1 (SCL)
i2c = I2C(0, scl=Pin(1), sda=Pin(0), freq=100000)
RTC_ADDR = 0x68

# Set the led for pin 16
led = Pin(16, Pin.OUT)
led.value(0) # Ensure LED starts turned off

sleep(0.01) # Wait for USB to connect
print("Hello, Pi Pico!")

def bcd_to_dec(bcd):
    """Convert Binary-Coded Decimal to standard decimal"""
    return (bcd // 16) * 10 + (bcd % 16)

# Ask the user for input to turn on led
try:
    target_hour = int(input("Enter target hour (0-23, e.g., 18 for 6 PM): "))
    target_minute = int(input("Enter target minute (0-59): "))
    print(f"Success! LED will turn on at {target_hour:02d}:{target_minute:02d}.")
except ValueError:
    print("Invalid input! Defaulting to 18:00 (6 PM).")
    target_hour = 18
    target_minute = 0

# Ask the user for input to turn off led
try:
    user_input_off = input("Enter the number of seconds before the LED turns off: ")
    target_time_seconds_off = int(user_input_off)
    print(f"Success! LED will turn off after {target_time_seconds_off} seconds.")
except ValueError:
    print("Invalid input! Defaulting to 10 seconds.")
    target_time_seconds_off = 10

elapsed_seconds = 0
led_has_turned_on = False

while True:
    try:
        # Read 7 bytes starting from register 0x00 (Seconds, Minutes, Hours, Day, Date, Month, Year)
        data = i2c.readfrom_mem(RTC_ADDR, 0x00, 7)    
        sec = bcd_to_dec(data[0] & 0x7F)  # Mask out the Clock Halt (CH) bit
        minute = bcd_to_dec(data[1])
        hour = bcd_to_dec(data[2] & 0x3F)  # Assume 24-hour mode
        date = bcd_to_dec(data[4])
        month = bcd_to_dec(data[5])
        year = bcd_to_dec(data[6]) + 2000
        
        # Print the formatted date and time
        print(f"Date: {year}-{month:02d}-{date:02d} | Time: {hour:02d}:{minute:02d}:{sec:02d} | Elapsed: {elapsed_seconds}s")
        
    except OSError:
        print("Failed to communicate with RTC. Check your wiring!")
        hour, minute = 0, 0  # Fallback if I2C hiccups

    # Check if the target clock time has arrived
    if not led_has_turned_on and hour == target_hour and minute == target_minute:
        led.value(1)
        print("Target time reached! LED is now ON.")
        led_has_turned_on = True
        elapsed_seconds = 0  # Reset elapsed seconds so the off-timer starts counting from zero right now!

    # Turn off led after set amount of time once it has turned on
    if led_has_turned_on and elapsed_seconds >= target_time_seconds_off:
        led.value(0)
        print("Target time reached! LED is now off.")
        break
        
    # Increment the elapsed time counter by 1 second each loop (only matters after LED turns on, but safe to keep running)
    if led_has_turned_on:
        elapsed_seconds += 1
        
    sleep(1)

print("Program has finished.")