from machine import Pin
import utime

trigger = Pin(3, Pin.OUT)
# Define the Trigger pin
echo = Pin(2, Pin.IN)
# Define the Echo pin
buzzer_pin = Pin(13, Pin.OUT)  
# Define the buzzer pin

# Define stepper motor control pins
stepper_pin1 = Pin(4, Pin.OUT)
stepper_pin2 = Pin(5, Pin.OUT)
stepper_pin3 = Pin(6, Pin.OUT)
stepper_pin4 = Pin(7, Pin.OUT)

# Define stepper motor sequence
stepper_sequence = [
    [1, 0, 0, 1],
    [1, 0, 0, 0],
    [1, 1, 0, 0],
    [0, 1, 0, 0],
    [0, 1, 1, 0],
    [0, 0, 1, 0],
    [0, 0, 1, 1],
    [0, 0, 0, 1]
]

def set_stepper_step(step):
    stepper_pin1.value(step[0])
    stepper_pin2.value(step[1])
    stepper_pin3.value(step[2])
    stepper_pin4.value(step[3])

def rotate_stepper(steps, direction):
    for _ in range(steps):
        if direction == "clockwise":
            for step in stepper_sequence[::-1]:
                set_stepper_step(step)
                utime.sleep_ms(10) 
                
        elif direction == "anticlockwise":
            for step in stepper_sequence:
                set_stepper_step(step)
                utime.sleep_ms(10)  
                

def ultra():
    trigger.low()
    utime.sleep_us(2)
    trigger.high()
    utime.sleep_us(5)
    trigger.low()

    while echo.value() == 0:
        signaloff = utime.ticks_us()
    while echo.value() == 1:
        signalon = utime.ticks_us()
    timpassed = signalon - signaloff
    distance = (timpassed * 0.0330) / 2

    if distance < 20:
        print("Obstacle detected! Distance:", distance, "cm")
        print("Vehicle is changing path...")
        rotate_stepper(50, "anticlockwise")  
        # Rotate anticlockwise for 50 steps 
        buzzer_pin.on()  # Turn on the buzzer
        utime.sleep(2)  # Delay before changing direction
        buzzer_pin.off()  # Turn off the buzzer
    else:
        print("No obstacle detected. Distance:", distance, "cm")
        print("Car is moving forward...")
        rotate_stepper(50, "clockwise")  
        # Rotate clockwise for 50 steps 
        utime.sleep(2)  # Delay before changing direction

while True:
    ultra()
    utime.sleep(1)