#!/usr/bin/env python3
# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

"""
Example for sending and receiving CAN frames via ASCII protocol (slcan).
"""

import sys
import time
import argparse

import can
import serial


def main():
    """main routine."""
    parser = argparse.ArgumentParser(description="CAN tester")
    parser.add_argument(
        "dev", action="store", help="CAN device like socket://192.168.0.127:2001"
    )
    args = parser.parse_args()
    try:
        bus = can.interface.Bus(
            bustype="slcan", channel=args.dev, rtscts=True, bitrate=125000
        )
    except serial.serialutil.SerialException as err:
        print(err)
        sys.exit(1)

    try:
        while True:
            msg = can.Message(
                arbitration_id=0x100,
                is_extended_id=False,
                data=[0x00, 0x01, 0x02, 0x03],
            )
            bus.send(msg)
            time.sleep(0.1)
            msg = bus.recv(0.1)
            if not msg:
                print("Timeout")
                continue
            data = "".join("{:02X} ".format(byte) for byte in msg.data)
            print("{:X} [{}] {}".format(msg.arbitration_id, msg.dlc, data))

    except KeyboardInterrupt:
        print("\nShutting down server...")
        bus.shutdown()
        print("Server shut down.")


if __name__ == "__main__":
    main()