from machine import Pin, time_pulse_us
import utime

# Define GPIO pins for Bin 1 (First sensor)
TRIG1 = Pin(15, Pin.OUT)  # Trigger pin for Bin 1 (Pin 21)
ECHO1 = Pin(14, Pin.IN)   # Echo pin for Bin 1 (Pin 19)

# Define GPIO pins for Bin 2 (Second sensor)
TRIG2 = Pin(16, Pin.OUT)  # Trigger pin for Bin 2 (Pin 22)
ECHO2 = Pin(17, Pin.IN)   # Echo pin for Bin 2 (Pin 22)

# Define GPIO pins for Bin 3 (Third sensor)
TRIG3 = Pin(18, Pin.OUT)  # Trigger pin for Bin 3 (Pin 24)
ECHO3 = Pin(19, Pin.IN)   # Echo pin for Bin 3 (Pin 25)

# Setup GPIO pins
TRIG1.low()
TRIG2.low()
TRIG3.low()
utime.sleep(2)  # Allow sensors to stabilize

# Function to measure distance for a given sensor
def measure_distance(TRIG, ECHO):
    # Send trigger pulse to start the ultrasonic sensor
    TRIG.high()
    utime.sleep_us(10)  # Pulse duration of 10 microseconds
    TRIG.low()

    # Measure the duration of the echo pulse
    try:
        pulse_time = time_pulse_us(ECHO, 1)  # Time the echo pulse (high state)
    except OSError:
        return None  # If no echo received

    # Calculate distance (speed of sound = 343 m/s)
    distance = (pulse_time * 0.0343) / 2  # Distance in centimeters
    return distance

# Function to categorize bin level based on distance
def categorize_bin_level(distance):
    if distance is None:
        return "No reading - Check sensor connections"
    elif distance > 30:
        return "🟢 Bin is Empty!"
    elif 20 <= distance <= 30:
        return "🟡 Bin is Filling!"
    elif 10 <= distance < 20:
        return "🟠 Bin is Almost Full!"
    else:
        return "🚨 Bin is Full!"

# Main program loop
try:
    print("You have 3 waste bins to monitor!")  # Message indicating three bins

    while True:
        # Measure distance for all three bins
        distance1 = measure_distance(TRIG1, ECHO1)
        distance2 = measure_distance(TRIG2, ECHO2)
        distance3 = measure_distance(TRIG3, ECHO3)

        # Get the status for all three bins
        bin1_status = categorize_bin_level(distance1)
        bin2_status = categorize_bin_level(distance2)
        bin3_status = categorize_bin_level(distance3)

        # Print the waste level for all three bins separately
        print("\nWaste Level for Bin 1:")
        print(bin1_status)
        
        print("\nWaste Level for Bin 2:")
        print(bin2_status)

        print("\nWaste Level for Bin 3:")
        print(bin3_status)

        utime.sleep(1)  # Wait for 1 second before taking the next reading

except KeyboardInterrupt:
    print("Measurement stopped")