import network
import time
from machine import Pin, PWM
from umqtt.simple import MQTTClient

# ---------------- MQTT Settings ----------------
MQTT_CLIENT_ID = "smart-dustbin"
MQTT_BROKER = "broker.mqttdashboard.com"
MQTT_USER = ""
MQTT_PASSWORD = ""
MQTT_TOPIC = "smartdustbin/status"

# ---------------- WiFi ----------------
print("Connecting to WiFi", end="")
wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.connect("Wokwi-GUEST", "")

while not wifi.isconnected():
    print(".", end="")
    time.sleep(0.1)

print(" Connected!")

# ---------------- MQTT ----------------
print("Connecting to MQTT...", end="")
client = MQTTClient(MQTT_CLIENT_ID,
                    MQTT_BROKER,
                    user=MQTT_USER,
                    password=MQTT_PASSWORD)
client.connect()
print(" Connected!")

# ---------------- Ultrasonic Sensor ----------------
trigger = Pin(5, Pin.OUT)
echo = Pin(18, Pin.IN)

# ---------------- Servo ----------------
servo = PWM(Pin(15), freq=50)

# Function to rotate servo
def set_angle(angle):
    duty = int((angle / 180) * 102 + 26)
    servo.duty(duty)

# Measure distance
def distance():
    trigger.off()
    time.sleep_us(2)

    trigger.on()
    time.sleep_us(10)
    trigger.off()

    while echo.value() == 0:
        start = time.ticks_us()

    while echo.value() == 1:
        end = time.ticks_us()

    duration = time.ticks_diff(end, start)

    dist = (duration * 0.0343) / 2
    return dist

# Initially close lid
set_angle(0)

while True:
    dist = distance()
    print("Distance:", dist, "cm")

    if dist < 20:
        print("Object Detected - Opening Lid")
        set_angle(90)

        client.publish(MQTT_TOPIC, "Dustbin Open")

        time.sleep(3)

        print("Closing Lid")
        set_angle(0)

        client.publish(MQTT_TOPIC, "Dustbin Closed")

    time.sleep(0.5)