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

# MQTT Server Parameters
MQTT_CLIENT_ID = "micropython-esp32-buzzer-mqtt"
MQTT_BROKER = "broker.mqttdashboard.com"
MQTT_TOPIC = "buzzer-activate"

buzzer_pins = [12, 27, 21, 15]
buzzer_pwm = [PWM(Pin(pin), freq=1000, duty=0) for pin in buzzer_pins]

current_buzzer = None
last_buzzer_activation_time = 0

def connect_to_wifi():
    # Connect to Wi-Fi
    print("Connecting to Wi-Fi", end="")
    sta_if = network.WLAN(network.STA_IF)
    sta_if.active(True)
    sta_if.connect('Wokwi-GUEST', '')
    while not sta_if.isconnected():
        print(".", end="")
        time.sleep(0.1)
    print(" Connected!")

def connect_to_mqtt_broker():
    # Connect to HiveMQ MQTT broker
    connect_to_wifi()
    print("Connecting to MQTT server... ", end="")
    client.connect()
    print("Connected!")
    client.subscribe(MQTT_TOPIC)
    print("Subscribed to {}".format(MQTT_TOPIC))

def buzzer_activate(buzzer_number):
    global current_buzzer, last_buzzer_activation_time

    # Check if enough time has passed since the last buzzer activation
    current_time = time.time()
    if (current_time - last_buzzer_activation_time) < 5:
        print("Not enough time has passed since the last buzzer activation.")
        return

    # Activate the corresponding buzzer
    if current_buzzer is not None:
        current_buzzer.value(0) 

    buzzer_pin = Pin(buzzer_pins[buzzer_number - 1], Pin.OUT)
    buzzer_pin.value(1) 
    current_buzzer = buzzer_pin

    # Update the last buzzer activation time
    last_buzzer_activation_time = current_time

def buzzer_message_received(topic, message):
    buzzer_number = int(message.decode("utf-8"))
    
    if 1 <= buzzer_number <= 4:
        print("Received from MQTT topic: {} - activating Buzzer {}".format(topic.decode("utf-8"), buzzer_number))
        buzzer_activate(buzzer_number)
    else:
        print("Invalid buzzer number! Must be between 1 and 4.")

# Set up buzzer pins
for buzzer_pin in buzzer_pins:
    Pin(buzzer_pin, Pin.OUT, value=0)

# Set up MQTT client
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER)
client.set_callback(buzzer_message_received)
connect_to_mqtt_broker()

try:
    while 1:
        client.wait_msg()
finally:
    client.disconnect()