"""Entry point for ``zkac-node-i2p-server``: same TCP node as ``zkac-node serve``, for I2P tunnels."""

from __future__ import annotations

import argparse
import sys

from .paths import user_dir
from .server import serve


def main() -> None:
    epilog = """
I2P setup (typical):
  1. Run this command so the node listens on the loopback address shown below.
  2. In I2P or i2pd, create a server tunnel (TCP) that forwards inbound I2P
     connections to that host:port (e.g. 127.0.0.1:9800).
  3. Note the published destination (…b32.i2p) and the tunnel’s virtual port.
     Clients use:  <destination>.b32.i2p:<port>  as the server argument to
     zkac-node (registry, grant, auth, net check, etc.).
  4. Clients must reach I2P (e.g. export ZKAC_SOCKS5_PROXY=127.0.0.1:4447).

Pins are stored per host:port string — clients should pin the same address they
use to connect (the .b32.i2p:port form, not localhost).
"""

    p = argparse.ArgumentParser(
        prog="zkac-node-i2p-server",
        description=(
            "Run the ZKAC node (registry + anonymous handshake) on TCP for exposure "
            "through an I2P server tunnel. This is zkac-node serve with I2P-oriented "
            "defaults and setup hints."
        ),
        epilog=epilog,
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )
    p.add_argument(
        "userid",
        help="user whose ~/.zkac/<userid>/server/ holds server state (unless --data-dir)",
    )
    p.add_argument("--data-dir", default=None, help="override server data directory")
    p.add_argument(
        "--host",
        default="127.0.0.1",
        help="bind address (default: 127.0.0.1 — forward here from your I2P tunnel)",
    )
    p.add_argument(
        "--port",
        type=int,
        default=9800,
        help="TCP port the node listens on (default: 9800)",
    )
    p.add_argument(
        "--no-i2p-banner",
        action="store_true",
        help="suppress I2P tunnel reminder text",
    )
    p.add_argument(
        "--allow-non-loopback",
        action="store_true",
        help="allow --host values outside loopback (default blocks non-loopback binds)",
    )
    args = p.parse_args()

    data_dir = args.data_dir
    if data_dir is None:
        data_dir = str(user_dir(args.userid) / "server")

    if not args.no_i2p_banner:
        print(
            "zkac-node-i2p-server: listening for plain TCP (expose this with an I2P server tunnel).\n"
            f"  bind: {args.host}:{args.port}\n"
            f"  data: {data_dir}\n"
            "Clients on I2P: set ZKAC_SOCKS5_PROXY if needed, then use host:port like "
            "mydest.b32.i2p:9800 with zkac-node commands.\n",
            file=sys.stderr,
        )

    serve(data_dir, args.host, args.port, allow_non_loopback=args.allow_non_loopback)


if __name__ == "__main__":
    main()