"""实例 USDT 永续合约信息（与实盘 ccxt 精度一致）。"""

from __future__ import annotations

from typing import Any, Callable, Optional, Tuple

from hub_calculator_market_lib import (
    amount_decimals_from_exchange,
    normalize_base_symbol,
    price_decimals_from_exchange,
    resolve_usdt_perp_symbol,
)
from hub_ohlcv_lib import normalize_price_tick, price_tick_from_market


def fetch_usdt_swap_market_info(
    *,
    base_or_symbol: str,
    normalize_symbol_input: Callable[[str], str],
    normalize_exchange_symbol: Callable[[str], str],
    ensure_markets_loaded: Callable[[], None],
    exchange: Any,
    exchange_id: str = "",
) -> dict[str, Any]:
    """供各实例 /api/hub/market 调用。"""
    raw = str(base_or_symbol or "").strip()
    if not raw:
        return {"ok": False, "msg": "请输入币种，如 ETH"}

    try:
        ensure_markets_loaded()
    except Exception as exc:
        return {"ok": False, "msg": f"加载市场失败: {exc}"}

    base_u = normalize_base_symbol(raw)
    hub_sym = normalize_symbol_input(raw if base_u else raw)
    try:
        ex_sym = normalize_exchange_symbol(hub_sym)
    except Exception:
        ex_sym = hub_sym

    sym, err = resolve_usdt_perp_symbol(exchange, base_u or hub_sym)
    if err and ex_sym:
        markets = getattr(exchange, "markets", None) or {}
        if ex_sym in markets:
            sym = ex_sym
            err = None
    if err or not sym:
        return {"ok": False, "msg": err or f"未找到 {base_u or raw}/USDT 永续合约"}

    market = exchange.market(sym)
    try:
        contract_size = float(market.get("contractSize") or 1.0)
    except (TypeError, ValueError):
        contract_size = 1.0
    if contract_size <= 0:
        contract_size = 1.0

    price_tick = normalize_price_tick(price_tick_from_market(exchange, sym))
    amt_dec = amount_decimals_from_exchange(exchange, sym)
    px_dec = price_decimals_from_exchange(exchange, sym, price_tick)
    min_amount = None
    try:
        min_amount = float((market.get("limits") or {}).get("amount", {}).get("min"))
    except (TypeError, ValueError):
        min_amount = None

    base_out = (market.get("base") or base_u or "").upper() or base_u
    return {
        "ok": True,
        "exchange": (exchange_id or "").strip().lower(),
        "base": base_out,
        "exchange_symbol": sym,
        "display_symbol": f"{base_out}/USDT" if base_out else sym,
        "contract_size": contract_size,
        "price_tick": price_tick,
        "price_decimals": px_dec,
        "amount_decimals": amt_dec,
        "min_amount": min_amount,
    }