import yaml
from opcua_connector import opcua_connector
import time
import argparse



def check_opcua_server(OPCcon):
    """State 0: Check if OPC UA server is reachable."""
    print("---- State 0 ----")
    try:
        OPCcon.opcuaclient.connect()  # Connection happens here
        print("OPC UA server is reachable.")
        return 1  # Move to state 1
    except Exception as e:
        print(f"Error connecting to OPC UA server: {e}")
        return 99

def establish_connection(OPCcon):
    """State 1: Establish connection to OPC UA server."""
    print("---- State 1 ----")
    try:
        if OPCcon.opcuaclient.uaclient:
            print("OPC UA connection established.")
            return 2
        else:
            print(f"Error establishing connection")
            return 99
    except Exception as e:
        print(f"Error establishing connection: {e}")
        return 99

def push_btn(OPCcon, btn_name):
    """State 2:"""
    print("---- State 2 ----")
    try:
        OPCcon.press_btn(btn_name)
        print("Press button done.")
        return 99
    except Exception as e:
        print(f"Error in Press button: {e}.")
        return 99


if __name__ == '__main__':
    # Argument parsing
    parser = argparse.ArgumentParser(description='Run OPC UA button press script.')
    parser.add_argument('-n', '--name', type=str, required=True, help='Button name to press (BTN_START or BTN_STOP)')
    args = parser.parse_args()
    btn_name = args.name  # Get button name from arguments
    # btn_name = 'BTN_STOP'  # Get button name from arguments

    # INIT
    config = yaml.safe_load(open('./cfg.yaml'))
    OPCcon = opcua_connector(config)

    # State machine loop
    state = 0
    active = True
    while active:
        if state == 0:
            state = check_opcua_server(OPCcon)
        elif state == 1:
            state = establish_connection(OPCcon)
        elif state == 2:
            state = push_btn(OPCcon, btn_name)
        else:
            active = False

    # Close the InfluxDB connection when done
    OPCcon.influxclient.close()
    OPCcon.opcuaclient.disconnect()  # Disconnect from OPC UA after state machine finishes