import signal, sys, time, os, json
import serial
import asyncio
from pymodbus.server.async_io import ModbusTcpServer
from pymodbus.datastore import ModbusSequentialDataBlock
from pymodbus.datastore import ModbusSlaveContext, ModbusServerContext
import argparse

async def measurement_weight(port, data):
    command_hex = '4430314B570D0A'
    command_bytes = bytes.fromhex(command_hex)

    while True:
        try:
            port.write(command_bytes)
            time.sleep(0.02)
            result = port.readline()
            result = str(result, 'utf-8')
            result = result.replace(' ', '')
            result = float(result.replace('\r\n', ''))
            result *= 1000
            result += 1000
            
            # print(result)
            
            # if result < 0.0:
            #     result = 0.0
            
            data.setValues(3, 1, [int(result)])
        except Exception as e:
            print(f'measurement_weight: \n{e}')
            port.close()
            time.sleep(0.5)
            port.open()
            pass
        
        await asyncio.sleep(1)

async def set_zero(port, data):
    command_hex = '4430314B5A0D0A'
    command_bytes = bytes.fromhex(command_hex)
    
    while True:
        try:
            val = data.getValues(1, 1, count=1)
            
            if val[0] == 1:
                port.write(command_bytes)
                result = port.readline()
                data.setValues(1, 1, [0])
            else:
                print(f'set_zero: \n{e}')
                pass
        except:
            pass
        
        await asyncio.sleep(1)

def exit_handler(signum, frame):
    print('Stop')
    sys.exit(0)

async def run_server(port, data):
    # TCP 서버 시작
    with open(os.path.join('./config.json'), encoding='UTF-8') as f:
        jsonData = json.load(f)
        
    server = ModbusTcpServer(context, address=(jsonData['modbus-server']['address'], jsonData['modbus-server']['port']))
    
    update_coil_task = asyncio.create_task(measurement_weight(port=port, data=data))
    update_hr_task = asyncio.create_task(set_zero(port=port, data=data))
    
    await server.serve_forever()
    await asyncio.gather(update_coil_task, update_hr_task)
    
if __name__ == '__main__':
    # Define serial port
    serial_port = serial.Serial('/dev/ttyMAX0', 115200, parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, timeout=1)

    # For detect Ctrl+C
    signal.signal(signal.SIGINT, exit_handler)

    # Create ModbusTCP server
    store = ModbusSlaveContext(
        co=ModbusSequentialDataBlock(0, [0] * 100),  # Coils
        hr=ModbusSequentialDataBlock(0, [0] * 100)  # Holding Registers
    )

    context = ModbusServerContext(slaves=store, single=True)
    loop = asyncio.get_event_loop()
    loop.run_until_complete(run_server(port=serial_port, data=store))