from machine import Pin
from umqtt.simple import MQTTClient

import time 
import json
import ujson
import network
import dht

# ============= Objects =============
led = Pin(4, Pin.OUT)
led.off()
dht_sensor = dht.DHT22(Pin(2))

# ============= WiFi =============
sta = network.WLAN(network.STA_IF)
if not sta.isconnected():
    print('connecting to network...')
    sta.active(True)
    sta.connect('Wokwi-GUEST', '')
    while not sta.isconnected():
        pass
print('network config:', sta.ifconfig())

# ============= MQTT Configuration =============
MQTT_CLIENT_ID = "ku3hqodm4qc6yhmbh88m"
USERNAME = "hlnp06zv5mnon3mvrzy8"
PASSWORD = "bgq5av4a66j4n88glc3q"

BROKER = "thingsboard.cloud"
PUB_TOPIC = "v1/devices/me/telemetry"
SUB_TOPIC = "v1/devices/me/attributes"
RPC_TOPIC = "v1/devices/me/rpc/request/+"

# ============= Callback: MQTT receive message =============
def on_message(topic, msg):
    """Handle incoming shared attribute + RPC messages"""
    print(f"[SUB] Topic: {topic}, Message: {msg}")
    
    # ===== Handle Shared Attributes =====
    if SUB_TOPIC in topic:
        try:
            msg_dict = ujson.loads(msg)
            if 'led_state' in msg_dict:
                led_state = msg_dict['led_state']
                if led_state:
                    led.on()
                    print("[LED] ON")
                else:
                    led.off()
                    print("[LED] OFF")
        except Exception as e:
            print(f"[ERROR] Parse attribute: {e}")
    
    # ===== Handle RPC (Force Publish) =====
    elif 'rpc/request' in topic:
        try:
            msg_dict = ujson.loads(msg)
            # RPC format: {"method": "publish_data", "params": {...}}
            method = msg_dict.get('method', '')
            request_id = topic.split('/')[-1]  # Extract request ID
            
            if method == 'publish_data' or method == 'forcePubData':
                print("[RPC] Force publish requested!")
                force_publish_data()
                
                # Send RPC response
                response_topic = f"v1/devices/me/rpc/response/{request_id}"
                response = ujson.dumps({"status": "success"})
                client.publish(response_topic, response)
                print("[RPC] Response sent")
            else:
                print(f"[RPC] Unknown method: {method}")
        except Exception as e:
            print(f"[ERROR] RPC parse: {e}")

# ============= Force Publish Function =============
def force_publish_data():
    """Publish DHT data immediately (for RPC)"""
    try:
        dht_sensor.measure()
        temp = dht_sensor.temperature()
        hum = dht_sensor.humidity()
        
        data = {
            "temperature": temp,
            "humidity": hum
        }
        data_json = ujson.dumps(data)
        
        client.publish(PUB_TOPIC, data_json)
        print(f"[FORCE] Temp: {temp:.2f}°C, Humidity: {hum:.2f}% - Published Immediately!")
    except Exception as e:
        print(f"[ERROR] Force publish: {e}")

# ============= MQTT Connect =============
print("MQTT Connecting...")
client = MQTTClient(
    client_id=MQTT_CLIENT_ID,
    server=BROKER,
    user=USERNAME,
    password=PASSWORD,
    keepalive=10000
)
client.set_callback(on_message)
client.connect()
print("MQTT Connected!")

# Subscribe to shared attributes + RPC
client.subscribe(SUB_TOPIC)
client.subscribe(RPC_TOPIC)
print(f"Subscribed to {SUB_TOPIC} and RPC")

# ============= Main Loop =============
print("\nStarting Praktikum 14 - Publish DHT + Subscribe LED + Force Publish RPC")
print("="*70)

last_publish = time.time()
publish_interval = 2  # seconds

while True:
    try:
        # ===== 1. CHECK INCOMING MESSAGES =====
        client.check_msg()
        
        # ===== 2. PUBLISH DHT DATA (periodically) =====
        current_time = time.time()
        if current_time - last_publish >= publish_interval:
            try:
                dht_sensor.measure()
                temp = dht_sensor.temperature()
                hum = dht_sensor.humidity()
                
                data = {
                    "temperature": temp,
                    "humidity": hum
                }
                data_json = ujson.dumps(data)
                
                client.publish(PUB_TOPIC, data_json)
                print(f"[PUB] Temp: {temp:.2f}°C, Humidity: {hum:.2f}% - Published (periodic)")
                
                last_publish = current_time
            except Exception as e:
                print(f"[ERROR] DHT read/publish: {e}")
        
        time.sleep(0.1)
    
    except KeyboardInterrupt:
        print("\n[BOOT] User interrupted")
        break
    except Exception as e:
        print(f"[ERROR] Main loop: {e}")
        time.sleep(1)

print("[BOOT] Program ended")