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

# WiFi Config
SSID = 'Wokwi-GUEST'
PASSWORD = ''

# MQTT Config
BROKER = 'broker.emqx.io'
PORT = 1883
TOPIC_PUB = b"distance"
TOPIC_SUB = b"door"
CLIENT_ID = b"publisher-door"

# Ultrasonic Pins
TRIG = Pin(5, Pin.OUT)
ECHO = Pin(18, Pin.IN)

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

# Connect WiFi
def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    wlan.connect(SSID, PASSWORD)
    print("🔌 Connecting WiFi...", end="")
    while not wlan.isconnected():
        print(".", end="")
        time.sleep(0.5)
    print("\n✅ Connected:", wlan.ifconfig())

# Servo Control
def set_servo(angle):
    duty = int(((angle / 180) * 102) + 26)  # map 0–180° to duty cycle
    servo.duty(duty)

# Distance Measurement
def get_distance():
    TRIG.value(0)
    time.sleep_us(2)
    TRIG.value(1)
    time.sleep_us(2)
    TRIG.value(0)

    duration = time_pulse_us(ECHO, 1, 30000)
    distance = (duration / 2) * 0.0343
    return distance

# Callback for subscriber messages
def message_callback(topic, msg):
    command = msg.decode()
    print(f"📩 Command received: {command}")

    if command == "CLOSE":
        print(" Door closed")
        set_servo(0)
    elif command == "OPEN":
        print("Opening Door")
        set_servo(90)
        time.sleep(0)

# Main loop
def main():
    client = MQTTClient(CLIENT_ID, BROKER, PORT)
    client.set_callback(message_callback)
    client.connect()
    print("✅ Connected to MQTT Broker")
    client.subscribe(TOPIC_SUB)

    try:
        while True:
            # Publish distance
            dist = get_distance()
            client.publish(TOPIC_PUB, str(dist))
            print(f"📤 Published Distance: {dist:.2f} cm")

            # Check incoming messages
            client.check_msg()
            time.sleep(1)
    finally:
        client.disconnect()

# Run
connect_wifi()
main()