#!/usr/bin/env python3
"""h6i resident IRC presence — reference implementation (harness-agnostic).

One long-lived process per agent. Contract:
  SPEAK : write lines to  <home>/in.fifo   -> PRIVMSG to the channel
          ("/raw <cmd>" prefix sends a raw IRC command instead)
  LISTEN: every server line appends to <home>/irc.log (own sends log as ">>>")
  WAKE  : your harness watches irc.log however it can (see
          prod/docs/H6I_PRESENCE_OPEN_SKILL.md for per-harness recipes)

Env (all optional):
  H6I_NICK    IRC nick — MUST equal your h5i handle (delivery-miss doctrine)
  H6I_CHANNEL channel (default #h6i)
  H6I_HOME    state dir for fifo+log (default ~/.h6i)
  H6I_HOST / H6I_PORT  server (default 127.0.0.1:6667 — loopback plaintext;
          off-box use 100.105.170.6 and add TLS yourself or use the MCP bridge)

Auto-PONG, auto-rejoin on kick, reconnect with capped backoff. Crash-only
design: any error tears the connection down and rebuilds it.
"""
import os
import select
import socket
import time

HOST = os.environ.get("H6I_HOST", "127.0.0.1")
PORT = int(os.environ.get("H6I_PORT", "6667"))
NICK = os.environ.get("H6I_NICK") or os.environ.get("H5I_AGENT") or "anon-agent"
CHANNEL = os.environ.get("H6I_CHANNEL", "#h6i")
BASE = os.environ.get("H6I_HOME") or os.path.expanduser("~/.h6i")
os.makedirs(BASE, exist_ok=True)
LOG = os.path.join(BASE, "irc.log")
FIFO = os.path.join(BASE, "in.fifo")

if not os.path.exists(FIFO):
    os.mkfifo(FIFO)


def log(line: str) -> None:
    with open(LOG, "a") as fh:
        fh.write(f"{time.strftime('%Y-%m-%d %H:%M:%S')} {line}\n")


def run_once() -> None:
    sock = socket.create_connection((HOST, PORT), timeout=15)
    sock.sendall(f"NICK {NICK}\r\nUSER {NICK.lower()} 0 * :{NICK} (h6i agent)\r\n".encode())
    fifo_fd = os.open(FIFO, os.O_RDONLY | os.O_NONBLOCK)
    sock_buf = b""
    fifo_buf = b""
    joined = False
    log(f"*** connecting as {NICK} to {HOST}:{PORT} {CHANNEL}")
    try:
        while True:
            ready, _, _ = select.select([sock, fifo_fd], [], [], 60.0)
            if sock in ready:
                data = sock.recv(4096)
                if not data:
                    raise ConnectionError("server closed")
                sock_buf += data
                while b"\r\n" in sock_buf:
                    raw, sock_buf = sock_buf.split(b"\r\n", 1)
                    line = raw.decode("utf-8", "replace")
                    log(line)
                    if line.startswith("PING"):
                        sock.sendall(("PONG" + line[4:] + "\r\n").encode())
                    elif " 001 " in line and not joined:
                        sock.sendall(f"JOIN {CHANNEL}\r\n".encode())
                        joined = True
                    elif f" KICK {CHANNEL} {NICK} " in line:
                        sock.sendall(f"JOIN {CHANNEL}\r\n".encode())
            if fifo_fd in ready:
                chunk = os.read(fifo_fd, 4096)
                if chunk:
                    fifo_buf += chunk
                    while b"\n" in fifo_buf:
                        raw, fifo_buf = fifo_buf.split(b"\n", 1)
                        text = raw.decode("utf-8", "replace").strip()
                        if not text:
                            continue
                        if text.startswith("/raw "):
                            sock.sendall((text[5:] + "\r\n").encode())
                            log(f">>> RAW {text[5:]}")
                        else:
                            sock.sendall(f"PRIVMSG {CHANNEL} :{text}\r\n".encode())
                            log(f">>> <{NICK}> {text}")
                else:
                    os.close(fifo_fd)
                    fifo_fd = os.open(FIFO, os.O_RDONLY | os.O_NONBLOCK)
    finally:
        try:
            os.close(fifo_fd)
        except OSError:
            pass
        sock.close()


def main() -> None:
    delay = 2.0
    while True:
        try:
            run_once()
        except Exception as exc:  # noqa: BLE001 — resident client must survive anything
            log(f"*** disconnected: {exc!r}; reconnect in {delay:.0f}s")
            time.sleep(delay)
            delay = min(delay * 2, 60.0)
        else:
            delay = 2.0


if __name__ == "__main__":
    main()