#!/usr/bin/env python3
"""Hugging Face Spaces launcher for the upstream FreeLLMAPI container.

FreeLLMAPI itself is a Node.js/React application. This small Python launcher
prepares the Space environment and explicitly forwards the server command to
the upstream privilege-dropping entrypoint.
"""
from __future__ import annotations

import os
import secrets
import sys
from pathlib import Path


def prepare_environment() -> None:
    data_dir = Path(os.environ.get("FREELLMAPI_DATA_DIR", "/data"))
    data_dir.mkdir(parents=True, exist_ok=True)

    os.environ.setdefault("NODE_ENV", "production")
    os.environ.setdefault("PORT", os.environ.get("SPACE_PORT", "7860"))
    os.environ.setdefault("FREEAPI_DB_PATH", str(data_dir / "freeapi.db"))

    # Keep a stable generated key beside the DB if a Space Secret was not set.
    # For a persistent deployment, mount a writable bucket at /data.
    if not os.environ.get("ENCRYPTION_KEY"):
        key_file = Path(
            os.environ.get("ENCRYPTION_KEY_FILE", str(data_dir / ".encryption-key"))
        )
        if not key_file.is_file() or key_file.stat().st_size == 0:
            key_file.parent.mkdir(parents=True, exist_ok=True)
            try:
                descriptor = os.open(
                    key_file,
                    os.O_WRONLY | os.O_CREAT | os.O_EXCL,
                    0o600,
                )
            except FileExistsError:
                # Another startup process created it first.
                pass
            else:
                with os.fdopen(descriptor, "w", encoding="utf-8") as handle:
                    handle.write(secrets.token_hex(32))
                    handle.write("\n")
        os.environ["ENCRYPTION_KEY"] = key_file.read_text(encoding="utf-8").strip()


def main() -> None:
    prepare_environment()

    # Dockerfile supplies this CMD explicitly. Keep the fallback to avoid ever
    # calling setpriv with an empty command (the error seen in the Space logs).
    command = sys.argv[1:] or ["node", "server/dist/index.js"]
    upstream_entrypoint = "/usr/local/bin/docker-entrypoint.sh"
    if not os.path.isfile(upstream_entrypoint):
        raise FileNotFoundError(
            f"Expected upstream FreeLLMAPI entrypoint at {upstream_entrypoint}"
        )

    os.execv(upstream_entrypoint, [upstream_entrypoint, *command])


if __name__ == "__main__":
    main()