import network
import time
import random
import socket
import struct

# ---------------- CONFIGURATION ----------------
BROKER = "broker.hivemq.com"
PORT = 1883

# Change this to "node1" for the first board, and "node2" for the second board
NODE_ID = "node2" 
CLIENT_ID = ("bridge_" + NODE_ID + "_combined").encode()

def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)

    if wlan.isconnected():
        return True

    print(f"[{NODE_ID}] Connecting to Wi-Fi...")
    try:
        wlan.connect("Wokwi-GUEST", "")
    except:
        pass

    for i in range(20):
        if wlan.isconnected():
            print(f"[{NODE_ID}] Wi-Fi Connected!")
            return True
        time.sleep(1)

    return False

def connect_mqtt():
    client = socket.socket()
    client.settimeout(10)

    address = socket.getaddrinfo(BROKER, PORT)[0][-1]
    client.connect(address)

    packet = b"\x10" + bytes([12 + len(CLIENT_ID)])
    packet += b"\x00\x04MQTT\x04\x02\x00\x3c"
    packet += bytes([0, len(CLIENT_ID)]) + CLIENT_ID

    client.send(packet)
    response = client.recv(4)

    if response[0] != 0x20 or response[3] != 0:
        raise Exception("MQTT connection failed")

    print(f"[{NODE_ID}] MQTT Connected!")
    return client

def publish_metric(client, metric_name, value):
    topic = f"bridge/{NODE_ID}/{metric_name}".encode()
    message = str(value).encode()

    length = 2 + len(topic) + len(message)
    packet = b"\x30" + bytes([length])
    packet += struct.pack("!H", len(topic))
    packet += topic + message

    client.send(packet)
    print(f"[{NODE_ID}] Published {metric_name}: {value}")

print(f"SMART BRIDGE - {NODE_ID.upper()} (ALL SENSORS)")

client = None
last_ping = time.time()

while True:
    try:
        if not connect_wifi():
            print(f"[{NODE_ID}] Wi-Fi unavailable. Retrying...")
            time.sleep(3)
            continue

        if client is None:
            print(f"[{NODE_ID}] Connecting to MQTT...")
            client = connect_mqtt()
            last_ping = time.time()

        # Read all three sensors on this single node
        vibration = random.randint(10, 100)
        temperature = random.randint(25, 60)
        strain = random.randint(100, 800)

        # Publish each sensor reading to its respective topic
        publish_metric(client, "vibration", vibration)
        publish_metric(client, "temperature", temperature)
        publish_metric(client, "strain", strain)

        if time.time() - last_ping >= 30:
            client.send(b"\xc0\x00")
            last_ping = time.time()

        print("----------------------")
        time.sleep(5)

    except Exception as error:
        print(f"[{NODE_ID}] Connection Error:", error)

        if client is not None:
            try:
                client.close()
            except:
                pass

        client = None
        print(f"[{NODE_ID}] Reconnecting in 3 seconds...")
        time.sleep(3)