import struct
import time
import threading
from pymodbus.client import ModbusTcpClient
from flask import Flask, jsonify

app = Flask(__name__)

modbus_data = {'rpm': 0, 'ai': 0, 'analog': 0}  # 全域變數儲存資料

def read_modbus_data():
    client = ModbusTcpClient(host="169.254.11.130", port=502)
    if client.connect():
        result = client.read_holding_registers(address=1633, count=6, slave=255)
        client.close()
        if result.isError():
            return {'rpm': 'Error', 'ai': 'Error', 'analog': 'Error'}
        else:
            regs = result.registers
            def to_float32(low, high):
                return struct.unpack('<f', struct.pack('<HH', low, high))[0]
            return {
                'rpm': to_float32(regs[0], regs[1]),
                'ai': to_float32(regs[2], regs[3]),
                'analog': to_float32(regs[4], regs[5]),
            }
    else:
        return {'rpm': 'Disconnected', 'ai': 'Disconnected', 'analog': 'Disconnected'}

def polling_loop():
    global modbus_data
    while True:
        modbus_data = read_modbus_data()
        print(modbus_data)  # ✅ 持續印出
        time.sleep(0.5)

@app.route("/")
def index():
    return "✅ Flask is running. Visit /modbus to get data."

@app.route("/modbus")
def get_data():
    return jsonify(modbus_data)

if __name__ == "__main__":
    threading.Thread(target=polling_loop, daemon=True).start()  # ✅ 背景輪詢
    app.run(host='127.0.0.1', port=5000, debug=True)