print("Smart Dust Bin")
print("Date: 18/11/2024" )
print("Created by A.Zul")

# Import libraries
import OLED_library
from Ultrasonic_lib import HCSR04  # Import the Ultrasonic sensor library
from machine import Pin, SoftI2C, PWM
from utime import sleep

# Declaration for OLED
oled_pin = SoftI2C(scl=Pin(22), sda=Pin(21))
OMER = OLED_library.SSD1306_I2C(width=128, height=64, i2c=oled_pin)

# Initialize ultrasonic sensor
sensor = HCSR04(trigger_pin=5, echo_pin=4)

# Define pins for LEDs
green_led = Pin(13, Pin.OUT)  # Green LED for "empty"
yellow_led = Pin(12, Pin.OUT)  # Yellow LED for "half-full"
red_led = Pin(14, Pin.OUT)  # Red LED for "full"

# Define buzzer with PWM
buzzer = PWM(Pin(27))


# Define servo motor (connected to GPIO 18)
servo = PWM(Pin(18))
servo.freq(50)  # Standard servo frequency: 50Hz

# Function to control the servo
def set_servo_angle(angle):
    # Convert angle to duty cycle (0-180 degrees maps to 0.5ms-2.5ms pulse width)
    duty = int((angle/ 180) * 102 + 26)  # Map 0°-180° to duty cycle
    servo.duty(duty)

def sound_buzzer_full():
    for _ in range(5):
        """
        Play two distinct sounds when the bin is full.
        """
        # First sound: High-pitched beep
        buzzer.freq(800)
        buzzer.duty(50)
        sleep(0.3)
        buzzer.duty(0)
        sleep(0.1)

        # Second sound: Low-pitched beep
        buzzer.freq(400)
        buzzer.duty(50)
        sleep(0.4)
        buzzer.duty(0)
        sleep(0.2)

def display_oled(message, distance):
    """
    Function to update the OLED display with status messages and distance.
    """
    OMER.fill(0)  # Clear the OLED
    OMER.text("Garbage Bin Status", 0, 0, 1)
    OMER.text(message, 0, 20, 1)
    OMER.text("Distance: {:.1f}cm".format(distance), 0, 40, 1)
    OMER.show()

def main():
    max_height = 106  # Maximum height of the garbage bin in cm
    full_threshold = 10  # Distance threshold for "full" in cm
    half_threshold = 53  # Distance threshold for "half-full" in cm

    while True:
        try:
            # Measure distance using the HC-SR04 sensor
            distance = sensor.distance_cm()
            print("Distance:", distance, "cm")

            # Calculate the fill level percentage
            fill_level = 100 - ((distance / max_height) * 100)
            print("Fill Level:", round(fill_level), "%")

            # Determine bin status
            if distance <= full_threshold:
                # Bin is full
                green_led.value(0)  # Turn off green
                yellow_led.value(0)  # Turn off yellow
                red_led.value(1)    # Turn on red
                sound_buzzer_full()  # Play the two distinct sounds
                set_servo_angle(0)  # Close the lid (angle 0°)
                display_oled("Bin is FULL!", distance)
                print("Bin is FULL!")

            elif distance <= half_threshold:
                # Bin is half-full
                green_led.value(0)  # Turn off green
                yellow_led.value(1)  # Turn on yellow
                red_led.value(0)    # Turn off red
                buzzer.duty(0)      # Turn off buzzer
                set_servo_angle(90)  # Keep lid partially open
                display_oled("Bin is HALF-FULL!", distance)
                print("Bin is HALF-FULL!")

            else:
                # Bin is empty
                green_led.value(1)  # Turn on green
                yellow_led.value(0)  # Turn off yellow
                red_led.value(0)    # Turn off red
                buzzer.duty(0)      # Turn off buzzer
                set_servo_angle(90)  # Keep lid fully open
                display_oled("Bin is EMPTY!", distance)
                print("Bin is EMPTY!")

        except OSError as e:
            print("Error reading from sensor:", e)
            display_oled("Sensor Error!", 0)

        sleep(0.1)

# Run the program
main()