import _thread
import select # <--- Built-in module to handle TLS timeouts
from machine import Pin
from shared import get_mqtt_client
from shared import config
import time

# --- Hardware Configuration ---
vext = Pin(19, Pin.OUT)
vext.value(0)
time.sleep_ms(100)

# --- Read Unique Device ID ---
try:
    with open("device_id.txt", "r") as f:
        DEVICE_ID = f.read().strip()
except Exception:
    DEVICE_ID = "ESP32_Inconnu"
    
MQTT_CA_FILE = "/certs/ca.crt"

# --- Setup MQTT Client ---
mqtt_client = get_mqtt_client(
    host=config.MQTT_BROKER_HOST,
    client_id="smartwave-esp32-" + DEVICE_ID,
    use_tls=config.USE_TLS,
    cafile=MQTT_CA_FILE,
    keepalive=config.MQTT_KEEPALIVE, # Can safely be 30 now
)

def on_mqtt_message(message):
    print("[MQTT Thread] Received message:", message)

mqtt_client.set_callback(on_mqtt_message)


def mqtt_background_thread():
    """Background MQTT worker using select.poll() for keepalive tracking."""
    print("[Thread] Background MQTT worker started.")
    
    while True:
        try:
            print("[Thread] Attempting connection to MQTT broker...")
            mqtt_client.connect()
            print("[Thread] Connected! Subscribing to topic...")
            mqtt_client.subscribe(config.MQTT_TOPIC, qos=config.MQTT_QOS)
            print("[Thread] Successfully subscribed. Setting up poller...")
            
            # --- THE SELECT POLLER SETUP ---
            # Create a poller and register our active TLS socket to look for incoming data (POLLIN)
            poller = select.poll()
            poller.register(mqtt_client._client.sock, select.POLLIN)
            
            # Listening loop
            while True:
                # Wait for network events for a maximum of 15000 milliseconds (15 seconds)
                events = poller.poll(15000)
                
                if not events:
                    # The 15 seconds expired with zero network traffic! 
                    # Send a keepalive ping to Mosquitto.
                    print("[Thread] No data for 15s. Sending keepalive ping...")
                    mqtt_client._client.ping()
                else:
                    # Data has physically arrived on the socket!
                    # Calling wait() now is completely safe and won't block indefinitely.
                    mqtt_client.wait()
                        
        except Exception as e:
            print("[Thread] Connection dropped or error encountered:", e)
            print("[Thread] Cleaning up socket context. Retrying in 5 seconds...")
            try:
                mqtt_client.close()
            except Exception:
                pass
            time.sleep(5)

# --- Launch background worker ---
_thread.start_new_thread(mqtt_background_thread, ())


# --- MAIN APPLICATION THREAD (Core 0) ---
print("[Main] Main execution path active.")
while True:
    # Your main physical loop runs completely unhindered here
    time.sleep(1)