from machine import Pin, time_pulse_us
import time
import tm1637

# Define pins connected to the HC-SR04 sensor
trigger_pin = Pin(4, Pin.OUT)
echo_pin = Pin(5, Pin.IN)

# Define pins connected to the TM1637 display
clk = Pin(1)
data = Pin(0)
display = tm1637.TM1637(clk, data)


red_led_pin = Pin(6,Pin.OUT)
yellow_led_pin = Pin(7, Pin.OUT)
green_led_pin = Pin(8, Pin.OUT)

buzzer_pin = Pin(9,Pin.OUT)

# Function to measure distance using HC-SR04 sensor
def measure_distance():
    """Measures the distance using the HC-SR04 ultrasonic sensor.

    Returns:
        float: The distance in centimeters, or None if an error occurs.
    """

    # Send a 10us pulse on the trigger pin to start the measurement
    trigger_pin.value(0)  # Ensure initial low state
    time.sleep_us(2)
    trigger_pin.value(1)
    time.sleep_us(10)
    trigger_pin.value(0)

    # Measure echo pulse duration with timeout
    duration = time_pulse_us(echo_pin, 1, 30000)  # Timeout of 30ms (adjustable)
    if duration is None:
        print("Error: Sensor timeout")
        return None

    # Calculate distance using speed of sound (343 m/s)
    # Divide by 2 for round trip measurement
    distance = duration * 0.0343 / 2

    return distance

def bacaan_lampu (height):
    red_led_pin.value(0)
    yellow_led_pin.value(0)
    green_led_pin.value(0)

    if  height >= 30:
        red_led_pin.value(1)
    elif height >= 20 :
        yellow_led_pin.value(1)
    else:
        green_led_pin.value(1)    

def control_buzzer(height):
    if height >= 30:
        buzzer_pin.value(1)
    else:
        buzzer_pin.value(0)

def display_height(height):
    """Displays a message on the TM1637 based on the height.

    Args:
        height (float): The distance in centimeters.
    """

    # Convert height to integer string (adjust based on display limitations)
    height_str = str(int(height)) if height < 100 else str(int(height / 10))  # Truncate for larger values

    # Determine indicator message based on height thresholds
    if height >= 30:
        indicator_message = "BAhaya"
    elif height >= 20:
        indicator_message = "Waspada"
    else:
        indicator_message = "aman"

    # Display message on the TM1637 (consider adding scrolling)
    display.scroll(indicator_message)  # Adjust display behavior as needed

def main():
    """Main program loop."""

    while True:
        # Measure distance and handle errors
        distance = measure_distance()
        if distance is None:
            continue

        # Convert distance to height (assuming sensor is horizontal)
        height = distance

        # Display height on TM1637 and potentially control LEDs or buzzer (add in separate functions as needed)
        display_height(height)

        bacaan_lampu (height)

        # Print distance for debugging or logging purposes
        print(f"Distance: {distance:.2f} cm")

        # Wait for a short period before next measurement
        time.sleep(1)

if __name__ == "__main__":
    main()