from pymodbus.client.sync import ModbusTcpClient

class WebRelay:
    def __init__(self, n_relay=10):
        self.n_relay = n_relay
        self.relay_status = [False for i in range(self.n_relay)]
        self.client = None 

    def __del__(self):
        if self.client:
            self.client.close()

    def apply_network_configs(self, nc_dict):
        self.ip_address = nc_dict["ipaddr"]
        self.port = nc_dict["port"]
        self.uid = nc_dict["uid"]

    def connect_slave(self):
        if not self.client:
            self.client = ModbusTcpClient(self.ip_address)
            self.client.connect()

    def disconnect_slave(self):
        if self.client:
            self.client.close()
            self.client = None

    def turn_relay_on(self, relay_id):
        '''
        :param relay_id: id of relay to turn on
        :return: None
        '''
        self.check_write_single_coil(relay_id, True)

    def turn_relay_off(self, relay_id):
        '''
        :param relay_id: id of relay to turn off
        :return: None
        '''
        self.check_write_single_coil(relay_id, False)

    def check_write_single_coil(self, relay_id, value):
        if self.client:
            self.client.write_coil(relay_id, value)