from machine import Pin, PWM
from time import sleep

# Set up PWM for an LED connected to GPIO 2
led = PWM(Pin(2), freq=1000)  # Operating at 1 kHz
led.duty(0)  # Begin with the LED turned off

# Set up a button on GPIO 0
button = Pin(0, Pin.IN, Pin.PULL_UP)  # Enable pull-up resistor

# Initialize brightness settings
duty_cycle = 0
is_increasing = True  # Flag to track brightness direction

while True:
    # Detect button press (active low)
    if not button.value():
        led.duty(0)  # Turn off the LED while the button is held
        duty_cycle = 0  # Reset brightness to zero
    else:
        # Adjust brightness only when the button is released
        if is_increasing:
            if duty_cycle < 1023:
                duty_cycle += 10  # Brighten the LED
                if duty_cycle > 1023:  # Limit to maximum value
                    duty_cycle = 1023
            else:
                is_increasing = False  # Start dimming
        else:
            if duty_cycle > 0:
                duty_cycle -= 10  # Dim the LED
                if duty_cycle < 0:  # Limit to minimum value
                    duty_cycle = 0
            else:
                is_increasing = True  # Start brightening

        led.duty(duty_cycle)  # Apply the current brightness setting
        sleep(0.01)  # Brief pause for smooth transitions