#!/usr/bin/env python3
"""Keep external comments on the agent's own Gitea pull requests."""
from __future__ import annotations

import json
import os
import sys

AGENT_USERNAME = os.environ.get("GITEA_AGENT_USERNAME", "luna")


def login(user: object) -> str:
    if not isinstance(user, dict):
        return ""
    return str(user.get("login") or user.get("username") or "")


def main() -> int:
    try:
        payload = json.load(sys.stdin)
    except (json.JSONDecodeError, OSError):
        return 1

    if not isinstance(payload, dict):
        return 1

    pull_request = payload.get("pull_request")
    comment = payload.get("comment")
    if not isinstance(pull_request, dict) or not isinstance(comment, dict):
        # Fail closed: only PR comment payloads for the agent's own PRs should
        # wake the route.
        return 0

    if login(pull_request.get("user")) != AGENT_USERNAME:
        return 0

    # Do not wake Hermes for its own reply, which would otherwise create a
    # comment -> run -> comment loop.
    if login(comment.get("user")) == AGENT_USERNAME:
        return 0

    json.dump(payload, sys.stdout, ensure_ascii=False, separators=(",", ":"))
    sys.stdout.write("\n")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())