import argparse
import readline
from importlib.util import spec_from_file_location, module_from_spec


def parse_args():
    parser = argparse.ArgumentParser(
            prog="Minecraft RCON Client",
            description="A simple RCON client for remotely controlling a Minecraft server. Can be used interactively or to run prespecified commands. Also supports running arbitrary Python scripts for more complex logic.")

    parser.add_argument("-H", "--host", help="The hostname of the RCON server.")
    parser.add_argument("-P", "--port", help="The port number of the RCON server. Default is 25575 if omitted and -H is specified. ", type=int)
    parser.add_argument("-p", "--password", help="The password to the RCON server.")

    execute_arg_group = parser.add_mutually_exclusive_group()
    execute_arg_group.add_argument("-e", "--execute-command", help="Send a single command on the RCON server. Can be passed multiple times to run multiple commands. Does not abort on server-side command failures. Requires -H and -p to be specified. Mutually exclusive with -E.", metavar="COMMAND", action='append')
    execute_arg_group.add_argument("-E", "--execute-file", help="Execute a Python file. Requires -H and -p to be specified. Mutually exclusive with -e.", metavar="FILEPATH")

    parser.add_argument("--echo", help="Echo a command before sending it. Does nothing when neither -e nor -E is present.", action="store_true")
    parser.add_argument("--socket-timeout", help="Set the timeout for the socket when waiting to receive data. Default 30 seconds.", type=float, metavar="TIMEOUT_SECONDS")

    args = parser.parse_args()

    if (args.execute_command or args.execute_file) and not (args.host and args.password):
        parser.error("-e/-E require -H and -p to be specified")

    return args


def safe_input(prompt: str) -> str:
    """Like `input()`, but Ctrl-C prints a fresh prompt and Ctrl-D cleanly exits"""
    while True:
        try:
            return input(prompt)
        except KeyboardInterrupt:
            print('^C')
        except EOFError:
            print()
            exit(0)


def load_script(script_path: str):
    # three stages to importing here: find the thing to import, initialize an empty module, and execute the top-level code in that module
    # here, we're essentially deciding which tool to use to read the script
    spec = spec_from_file_location("user_script", script_path)
    if spec is None:
        raise ValueError(f"{script_path} is not a valid Python file path")

    # initialize an empty "box" that we'll populate with all of our code
    module = module_from_spec(spec)
    # execute the top-level code (function definitions, global variables, etc.)
    spec.loader.exec_module(module) # pyright: ignore

    if not hasattr(module, "run"):
        raise ValueError(f"Provided script {script_path} must define a run(sock) function")

    return module