"""
CEG5103/EE5024 - Industrial IoT for Machine Failure Prediction
Student 5: Response Node (Basic Implementation)
- Subscribes to ThingSpeak Field 5 for predictions
- Green LED for normal status (Pin 2)
- Red LED + Buzzer for anomaly alert (Pin 4, Pin 15)

Hardware:
- ESP32 Development Board
- Green LED -> Pin 2
- Red LED   -> Pin 4
- Buzzer    -> Pin 15
"""

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

# ===== HARDWARE CONFIGURATION =====
LED_GREEN = Pin(2, Pin.OUT)
LED_RED = Pin(4, Pin.OUT)
BUZZER = PWM(Pin(15))
BUZZER.freq(1000)
BUZZER.duty(0)

# ===== ACTUATION FUNCTIONS =====
def set_normal_mode():
    """Normal operation: Green LED ON, Red LED OFF, Buzzer OFF"""
    LED_GREEN.value(1)
    LED_RED.value(0)
    BUZZER.duty(0)
    print("   [ACTUATOR] Green LED ON - Machine NORMAL")

def set_anomaly_mode():
    """Anomaly detected: Green LED OFF, Red LED ON, Buzzer sounds"""
    LED_GREEN.value(0)
    LED_RED.value(1)
    BUZZER.duty(512)
    time.sleep(0.5)
    BUZZER.duty(0)
    print("   [ACTUATOR] Red LED ON - ANOMALY DETECTED")
    print("   [ACTUATOR] Buzzer SOUNDING - ALERT!")

def set_idle_mode():
    """Idle state: All LEDs OFF, Buzzer OFF"""
    LED_GREEN.value(0)
    LED_RED.value(0)
    BUZZER.duty(0)
    print("   [ACTUATOR] System IDLE")

def flash_led(led, times=3, duration=0.2):
    for _ in range(times):
        led.value(1)
        time.sleep(duration)
        led.value(0)
        time.sleep(duration)

# ===== WIFI & MQTT CONFIGURATION =====
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""

CHANNEL_ID = "3293129"
MQTT_CLIENT_ID = "ORwNMAYKEg0kCiUsLxk4LSY"
MQTT_USER = "ORwNMAYKEg0kCiUsLxk4LSY"
MQTT_PASS = "oniySoxRWcSviO9bvemQbAE1"
MQTT_SERVER = "mqtt3.thingspeak.com"
MQTT_PORT = 1883
MQTT_TOPIC = f"channels/{CHANNEL_ID}/subscribe/fields/field5"

STATUS_NORMAL = 0
STATUS_ANOMALY = 1

def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    wlan.connect(WIFI_SSID, WIFI_PASSWORD)
    print(f"\nConnecting to WiFi: {WIFI_SSID}", end="")
    for i in range(30):
        if wlan.isconnected():
            print("\nWiFi Connected Successfully")
            print("IP Address: " + wlan.ifconfig()[0])
            flash_led(LED_GREEN, times=2, duration=0.1)
            return wlan
        print(".", end="")
        time.sleep(1)
    print("\nWiFi Connection Failed")
    return None

def connect_mqtt():
    try:
        gc.collect()
        print(f"\nConnecting to ThingSpeak MQTT...")
        print(f"   Server: {MQTT_SERVER}:{MQTT_PORT}")
        print(f"   Client ID: {MQTT_CLIENT_ID}")
        print(f"   Subscribing to: {MQTT_TOPIC}")
        client = MQTTClient(
            client_id=MQTT_CLIENT_ID,
            server=MQTT_SERVER,
            port=MQTT_PORT,
            user=MQTT_USER,
            password=MQTT_PASS,
            keepalive=60
        )
        client.connect()
        print("MQTT Connected Successfully")
        flash_led(LED_GREEN, times=1, duration=0.2)
        return client
    except Exception as e:
        print("MQTT Connection Failed: " + str(e))
        return None

def mqtt_callback(topic, msg):
    try:
        prediction = int(msg.decode('utf-8'))
        print(f"\n{'='*50}")
        print(f"MQTT Message Received")
        print(f"   Topic: {topic}")
        print(f"   Prediction: {prediction}")
        
        if prediction == STATUS_NORMAL:
            print(f"\nSTATUS: NORMAL OPERATION")
            set_normal_mode()
        elif prediction == STATUS_ANOMALY:
            print(f"\nSTATUS: ANOMALY DETECTED!")
            set_anomaly_mode()
            flash_led(LED_RED, times=3, duration=0.2)
        print(f"{'='*50}\n")
    except Exception as e:
        print(f"Callback error: {e}")

def main():
    print("="*60)
    print("CEG5103/EE5024 - Industrial IoT System")
    print("Student 5: Response Node")
    print("="*60)
    print("\nHardware Configuration:")
    print("   - Green LED   : Pin 2")
    print("   - Red LED     : Pin 4")
    print("   - Buzzer      : Pin 15")
    print("="*60)
    
    set_idle_mode()
    
    wlan = connect_wifi()
    if not wlan:
        return
    
    mqtt_client = connect_mqtt()
    if not mqtt_client:
        return
    
    mqtt_client.set_callback(mqtt_callback)
    mqtt_client.subscribe(MQTT_TOPIC)
    print(f"\nSubscribed to: {MQTT_TOPIC}")
    print("\nSystem READY! Waiting for predictions...")
    print("Press Ctrl+C to stop\n")
    
    flash_led(LED_GREEN, times=3, duration=0.1)
    
    last_connection_check = time.time()
    
    try:
        while True:
            mqtt_client.check_msg()
            
            current_time = time.time()
            if current_time - last_connection_check > 30:
                try:
                    mqtt_client.ping()
                except:
                    print("\nMQTT connection lost. Reconnecting...")
                    mqtt_client = connect_mqtt()
                    if mqtt_client:
                        mqtt_client.set_callback(mqtt_callback)
                        mqtt_client.subscribe(MQTT_TOPIC)
                last_connection_check = current_time
            
            time.sleep(0.05)
            
    except KeyboardInterrupt:
        print("\n\nProgram stopped by user")
    finally:
        set_idle_mode()
        if mqtt_client:
            mqtt_client.disconnect()
        BUZZER.deinit()
        print("System shutdown complete")

if __name__ == "__main__":
    main()