"""
WebSocket 재연결 대기 간격 — **REST 아님** (소켓 run_forever 끊김 후 재접속 전 sleep).

기본 시퀀스: 1 → 3 → 5 → 7 → 10초, 이후 10초 유지.
env ``WS_RECONNECT_DELAY_SECS`` (쉼표 구분, DB/env_config).
"""
from __future__ import annotations

from typing import List, Tuple

from ..utils.env import get_env_from_db

_DEFAULT_DELAYS: Tuple[float, ...] = (1.0, 3.0, 5.0, 7.0, 10.0)
_cache: Tuple[float, ...] | None = None


def invalidate_ws_reconnect_delay_cache() -> None:
    global _cache
    _cache = None


def ws_reconnect_delays_sec() -> Tuple[float, ...]:
    global _cache
    if _cache is None:
        raw = (
            get_env_from_db("WS_RECONNECT_DELAY_SECS", "1,3,5,7,10")
            or "1,3,5,7,10"
        ).strip()
        parts: List[float] = []
        for piece in raw.split(","):
            piece = piece.strip()
            if not piece:
                continue
            try:
                val = float(piece)
            except ValueError:
                continue
            if val >= 0:
                parts.append(val)
        _cache = tuple(parts) if parts else _DEFAULT_DELAYS
    return _cache


def ws_reconnect_delay_for_attempt(attempt: int) -> float:
    """1-based 재연결 시도 번호 → 대기 초. 시퀀스 초과 시 마지막 값."""
    if attempt < 1:
        attempt = 1
    delays = ws_reconnect_delays_sec()
    idx = min(attempt - 1, len(delays) - 1)
    return delays[idx]