#!/usr/bin/env python3
"""Add explicit parent lineage to Hermes API-created sessions."""

from __future__ import annotations

import argparse
from pathlib import Path


BEFORE = '''        model = body.get("model") or self._model_name
        system_prompt = body.get("system_prompt")
        if system_prompt is not None and not isinstance(system_prompt, str):
            return web.json_response(_openai_error("system_prompt must be a string", code="invalid_system_prompt"), status=400)
        db.create_session(session_id, "api_server", model=str(model) if model else None, system_prompt=system_prompt)
'''

AFTER = '''        model = body.get("model") or self._model_name
        system_prompt = body.get("system_prompt")
        if system_prompt is not None and not isinstance(system_prompt, str):
            return web.json_response(_openai_error("system_prompt must be a string", code="invalid_system_prompt"), status=400)

        # API workers are first-class children of the objective that launched
        # them.  Accept a JSON field for normal clients and a header for thin
        # relays that cannot extend their request schema.
        metadata = body.get("metadata")
        metadata_parent = metadata.get("parent_session_id") if isinstance(metadata, dict) else None
        raw_parent = body.get("parent_session_id") or metadata_parent or request.headers.get(
            "X-Hermes-Parent-Session-Id"
        )
        parent_session_id = str(raw_parent).strip() if raw_parent else None
        if parent_session_id:
            if (
                len(parent_session_id) > self._MAX_SESSION_HEADER_LEN
                or re.search(r'[\\r\\n\\x00]', parent_session_id)
                or _is_path_unsafe(parent_session_id)
                or parent_session_id == session_id
            ):
                return web.json_response(_openai_error("Invalid parent session ID", code="invalid_parent_session_id"), status=400)
            if not db.get_session(parent_session_id):
                return web.json_response(_openai_error(f"Parent session not found: {parent_session_id}", code="parent_session_not_found"), status=404)

        db.create_session(
            session_id,
            "api_server",
            model=str(model) if model else None,
            system_prompt=system_prompt,
            parent_session_id=parent_session_id,
        )
'''


def patch(source: Path, destination: Path) -> None:
    """Apply the narrow session-lineage extension and fail on upstream drift."""
    content = source.read_text(encoding="utf-8")
    if BEFORE not in content:
        raise RuntimeError("Hermes API session patch context changed")
    destination.parent.mkdir(parents=True, exist_ok=True)
    destination.write_text(content.replace(BEFORE, AFTER, 1), encoding="utf-8")


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("source", type=Path)
    parser.add_argument("destination", type=Path)
    args = parser.parse_args()
    patch(args.source, args.destination)
    return 0


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