#!/usr/bin/env python3
"""Operator-facing entrypoint for the DITAv2 kernel.

The launcher is env-driven and intentionally conservative by default:
- mock venue
- in-memory Zinc plane
- callback projection
- control-plane values may be overridden via DITA_V2_* env vars
"""

from __future__ import annotations

import json
import os
import signal
import time
from pathlib import Path
import sys

from dotenv import load_dotenv

PROJECT_ROOT = Path(__file__).parent.parent
load_dotenv(PROJECT_ROOT / ".env")
sys.path.insert(0, str(PROJECT_ROOT / "prod"))
sys.path.insert(0, str(PROJECT_ROOT / "prod" / "clean_arch"))
sys.path.insert(0, str(PROJECT_ROOT))

from prod.clean_arch.dita_v2.launcher import build_launcher_bundle


def _env_bool(name: str, default: bool = False) -> bool:
    raw = os.environ.get(name)
    if raw is None:
        return default
    return str(raw).strip().lower() in {"1", "true", "yes", "on"}


def _env_float(name: str, default: float) -> float:
    raw = os.environ.get(name)
    if raw is None:
        return default
    try:
        value = float(str(raw).strip())
    except Exception:
        return default
    return value if value > 0 else default


def _env_mode() -> str:
    mode = str(os.environ.get("DITA_V2_LAUNCHER_MODE", "serve")).strip().lower()
    if mode in {"once", "serve"}:
        return mode
    return "serve"


def _serve(bundle) -> int:
    interval = _env_float("DITA_V2_LAUNCHER_HEARTBEAT_SEC", 30.0)
    stop = False

    def _handle_signal(signum, _frame) -> None:
        nonlocal stop
        stop = True

    previous_term = signal.signal(signal.SIGTERM, _handle_signal)
    previous_int = signal.signal(signal.SIGINT, _handle_signal)
    try:
        print(
            json.dumps(
                {
                    "status": "serving",
                    "control": bundle.kernel.control.as_dict(),
                    "venue": type(bundle.venue).__name__,
                    "zinc_plane": type(bundle.zinc_plane).__name__,
                    "projection": type(bundle.projection).__name__,
                    "heartbeat_sec": interval,
                },
                indent=2,
                sort_keys=True,
                default=str,
            )
        )
        while not stop:
            time.sleep(interval)
        return 0
    finally:
        signal.signal(signal.SIGTERM, previous_term)
        signal.signal(signal.SIGINT, previous_int)


def main() -> int:
    bundle = build_launcher_bundle()
    try:
        mode = _env_mode()
        if mode == "once" or _env_bool("DITA_V2_PRINT_SNAPSHOT", False):
            print(json.dumps(bundle.kernel.snapshot(), indent=2, sort_keys=True, default=str))
            return 0
        return _serve(bundle)
    finally:
        bundle.close()


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