"""OKX REST 只读行情。禁止任何交易类接口。"""

from __future__ import annotations

from typing import Any

import httpx


def safe_float(v: Any) -> float | None:
    if v is None or v == "":
        return None
    try:
        return float(v)
    except (TypeError, ValueError):
        return None


class OkxRestClient:
    """仅调用公开行情 / 公共接口。"""

    # 硬黑名单：防止误用交易路径
    _FORBIDDEN_PREFIXES = (
        "/api/v5/trade",
        "/api/v5/account",
        "/api/v5/asset",
        "/api/v5/users",
    )

    def __init__(
        self,
        base_url: str = "https://www.okx.com",
        timeout: float = 15.0,
        proxy: str | None = None,
    ) -> None:
        self.base_url = base_url.rstrip("/")
        self.proxy = (proxy or "").strip() or None
        self._client = httpx.Client(
            base_url=self.base_url,
            timeout=timeout,
            proxy=self.proxy,
            headers={"Accept": "application/json", "User-Agent": "market_intel/0.1"},
        )

    def close(self) -> None:
        self._client.close()

    def __enter__(self) -> OkxRestClient:
        return self

    def __exit__(self, *args: object) -> None:
        self.close()

    def _get(self, path: str, params: dict[str, Any] | None = None) -> list[dict[str, Any]]:
        for bad in self._FORBIDDEN_PREFIXES:
            if path.startswith(bad):
                raise RuntimeError(f"forbidden trading path: {path}")
        r = self._client.get(path, params=params or {})
        r.raise_for_status()
        body = r.json()
        if str(body.get("code")) != "0":
            raise RuntimeError(f"OKX REST error code={body.get('code')} msg={body.get('msg')}")
        data = body.get("data") or []
        return [x for x in data if isinstance(x, dict)]

    def _get_raw(self, path: str, params: dict[str, Any] | None = None) -> list[Any]:
        for bad in self._FORBIDDEN_PREFIXES:
            if path.startswith(bad):
                raise RuntimeError(f"forbidden trading path: {path}")
        r = self._client.get(path, params=params or {})
        r.raise_for_status()
        body = r.json()
        if str(body.get("code")) != "0":
            raise RuntimeError(f"OKX REST error code={body.get('code')} msg={body.get('msg')}")
        data = body.get("data") or []
        return data if isinstance(data, list) else []

    def fetch_option_instruments(self, inst_family: str) -> list[dict[str, Any]]:
        rows = self._get(
            "/api/v5/public/instruments",
            {"instType": "OPTION", "instFamily": inst_family},
        )
        return [r for r in rows if str(r.get("state") or "").lower() == "live"]

    def fetch_index_ticker(self, inst_id: str) -> float | None:
        rows = self._get("/api/v5/market/index-tickers", {"instId": inst_id})
        if not rows:
            return None
        return safe_float(rows[0].get("idxPx"))

    def fetch_index_at(
        self, inst_id: str, target_ts_ms: int
    ) -> tuple[float | None, int | None]:
        """
        用 1m 历史指数 K 线取最接近 target 的收盘价。
        OKX: /api/v5/market/history-index-candles
        candle: [ts, o, h, l, c, confirm, ...]
        """
        # before = 请求此时间戳之前的数据；取到期前后窗口
        before = int(target_ts_ms) + 60_000
        after = int(target_ts_ms) - 10 * 60_000
        rows = self._get_raw(
            "/api/v5/market/history-index-candles",
            {
                "instId": inst_id,
                "bar": "1m",
                "before": str(before),
                "after": str(after),
                "limit": "20",
            },
        )
        best_px: float | None = None
        best_ts: int | None = None
        best_delta: int | None = None
        for row in rows:
            if not isinstance(row, (list, tuple)) or len(row) < 5:
                continue
            ts = safe_float(row[0])
            close = safe_float(row[4])
            if ts is None or close is None:
                continue
            ts_i = int(ts)
            delta = abs(ts_i - int(target_ts_ms))
            if best_delta is None or delta < best_delta:
                best_delta = delta
                best_px = close
                best_ts = ts_i
        if best_delta is not None and best_delta > 5 * 60_000:
            return None, None
        return best_px, best_ts

    def fetch_books(
        self, inst_id: str, sz: int = 5
    ) -> tuple[float | None, float | None, float | None, float | None, int | None]:
        """返回 ask, bid, ask_sz, bid_sz, ts_ms。"""
        rows = self._get(
            "/api/v5/market/books",
            {"instId": inst_id, "sz": str(max(1, min(int(sz), 400)))},
        )
        if not rows:
            return None, None, None, None, None
        row = rows[0]
        ts = safe_float(row.get("ts"))
        ts_ms = int(ts) if ts is not None else None
        asks = row.get("asks") or []
        bids = row.get("bids") or []
        ask = ask_sz = bid = bid_sz = None
        if asks and isinstance(asks[0], (list, tuple)) and len(asks[0]) >= 2:
            ask = safe_float(asks[0][0])
            ask_sz = safe_float(asks[0][1])
        if bids and isinstance(bids[0], (list, tuple)) and len(bids[0]) >= 2:
            bid = safe_float(bids[0][0])
            bid_sz = safe_float(bids[0][1])
        return ask, bid, ask_sz, bid_sz, ts_ms