#!/usr/bin/env python3
"""
Весовой сервис для Orange Pi
Читает данные с весового терминала A9 через USB-RS232 (WaveShare конвертер)
и публикует вес в MQTT топик scale/weight

Установка:
    pip3 install pyserial paho-mqtt --break-system-packages

Автозапуск:
    systemctl enable scales
    systemctl start scales
"""
import subprocess
import paho.mqtt.client as mqtt
import re
import time
import datetime

SERIAL_PORT = '/dev/ttyUSB0'
SERIAL_BAUD = 9600

# MQTT локальный (сервер с ИИ системой)
MQTT1_HOST = '192.168.20.9'
MQTT1_PORT = 1883
MQTT1_USER = ''
MQTT1_PASS = ''

# MQTT наш VPS
MQTT2_HOST = '77.222.43.248'
MQTT2_PORT = 1884
MQTT2_USER = 'esp32'
MQTT2_PASS = 'Esp32Scales#2026'

MQTT_WEIGHT_TOPIC = 'scale/weight'
MQTT_GO_TOPIC     = 'scale/traffic/go'

MIN_WEIGHT   = 200   # кг — минимум для определения машины на платформе
STABLE_DELTA = 50    # кг — допустимый разброс для стабилизации
STABLE_TIME  = 10    # сек — время стабилизации

gpio_ok = False

def on_message(client, userdata, msg):
    print(f"[MQTT] {msg.topic}: {msg.payload}")
    if msg.topic == MQTT_GO_TOPIC:
        print("[LIGHT] Получен GO — зелёный!")

mqtt1 = mqtt.Client(client_id="scales_opi_1")
mqtt2 = mqtt.Client(client_id="scales_opi_2")

def mqtt_connect():
    try:
        mqtt1.on_message = on_message
        mqtt1.connect(MQTT1_HOST, MQTT1_PORT, keepalive=60)
        mqtt1.subscribe(MQTT_GO_TOPIC)
        mqtt1.loop_start()
        print("[MQTT1] Подключён к 192.168.20.9")
    except Exception as e:
        print(f"[MQTT1] Ошибка: {e}")
    try:
        mqtt2.username_pw_set(MQTT2_USER, MQTT2_PASS)
        mqtt2.connect(MQTT2_HOST, MQTT2_PORT, keepalive=60)
        mqtt2.loop_start()
        print("[MQTT2] Подключён к VPS")
    except Exception as e:
        print(f"[MQTT2] Ошибка: {e}")

def publish_weight(w):
    ts = datetime.datetime.now().strftime('%Y-%m-%dT%H:%M:%S')
    payload = f"{w:.1f}"
    try:
        mqtt1.publish(MQTT_WEIGHT_TOPIC, payload)
        print(f"[MQTT1] Отправлен вес: {payload} кг в {ts}")
    except Exception as e:
        print(f"[MQTT1] Ошибка: {e}")
    try:
        mqtt2.publish(MQTT_WEIGHT_TOPIC, payload)
        print(f"[MQTT2] Отправлен вес: {payload} кг в {ts}")
    except Exception as e:
        print(f"[MQTT2] Ошибка: {e}")

def parse_weight(data):
    """
    Формат A9: STX + +XXXXXXX_C + ETX
    Пример: \x02+00176001B\x03 = 1760.0 кг
    """
    m = re.search(rb'\x02([+-]\d{8}[A-Z0-9])\x03', data)
    if m:
        s = m.group(1).decode('ascii')
        digits = s[1:8]  # 7 цифр без знака и контрольной суммы
        w = float(digits[:-1] + '.' + digits[-1])
        return w
    return None

def main():
    mqtt_connect()
    print("[BOOT] Готов, жду машину...")

    subprocess.run(['stty', '-F', '/dev/ttyUSB0', 'raw', '9600',
                    'cs8', '-cstopb', '-parenb'])

    proc = subprocess.Popen(
        ['cat', '/dev/ttyUSB0'],
        stdout=subprocess.PIPE,
        stderr=subprocess.DEVNULL
    )

    state = 'EMPTY'
    last_weights = []
    buf = b""

    while True:
        try:
            chunk = proc.stdout.read(12)
            if not chunk:
                time.sleep(0.1)
                continue
        except:
            time.sleep(0.1)
            continue

        buf += chunk
        while b'\x02' in buf and b'\x03' in buf:
            s = buf.find(b'\x02')
            e = buf.find(b'\x03', s)
            if s == -1 or e == -1:
                break
            frame = buf[s:e+1]
            buf = buf[e+1:]
            w = parse_weight(frame)
            if w is None:
                continue

            now = time.time()
            print(f"[RAW] {w} кг")

            if state == 'EMPTY':
                if w >= MIN_WEIGHT:
                    state = 'LOADING'
                    last_weights = []
                    print(f"[STATE] Машина заезжает: {w} кг")

            elif state == 'LOADING':
                if w < MIN_WEIGHT / 2:
                    state = 'EMPTY'
                    last_weights = []
                    print("[STATE] Машина уехала")
                    continue
                last_weights.append((now, w))
                last_weights = [(t, v) for t, v in last_weights
                                if now - t <= STABLE_TIME]
                if len(last_weights) >= 5:
                    vals = [v for _, v in last_weights]
                    if max(vals) - min(vals) <= STABLE_DELTA:
                        avg = sum(vals) / len(vals)
                        print(f"[STATE] Вес стабилен: {avg:.1f} кг")
                        publish_weight(avg)
                        state = 'WAIT_GO'
                        print("[STATE] Жду GO от сервера")

            elif state == 'WAIT_GO':
                if w < MIN_WEIGHT / 2:
                    state = 'EMPTY'
                    print("[STATE] Машина уехала без GO")

if __name__ == '__main__':
    main()