"""按账户资金推荐可交易品种（期货核心筛选）。"""
from __future__ import annotations

from concurrent.futures import ThreadPoolExecutor
from typing import Callable, Optional

from contract_specs import get_contract_spec
from symbols import PRODUCTS


def _letters_from_ths(ths_code: str) -> str:
    import re
    m = re.match(r"^([A-Za-z]+)", (ths_code or "").strip())
    return m.group(1) if m else ""


def assess_product_for_capital(
    product: dict,
    capital: float,
    price: Optional[float],
    *,
    max_position_pct: float = 50.0,
    default_stop_ticks: int = 20,
) -> dict:
    """评估单品种在当前资金下是否可交易。"""
    ths = product.get("ths") or ""
    name = product.get("name") or ths
    exchange = product.get("exchange") or ""
    spec = get_contract_spec(ths + "8888")
    mult = spec["mult"]
    margin_rate = spec["margin_rate"]
    tick = float(spec.get("tick_size") or 1.0)
    p = float(price) if price and price > 0 else 0.0
    cap = float(capital or 0)

    if p <= 0:
        return {
            "ths": ths,
            "name": name,
            "exchange": exchange,
            "status": "no_price",
            "status_label": "暂无行情",
            "min_capital_one_lot": None,
            "margin_one_lot": None,
            "risk_one_lot_1pct": None,
        }

    margin_one = p * mult * margin_rate
    min_capital = margin_one / (max_position_pct / 100.0) if max_position_pct > 0 else margin_one
    stop_dist = tick * default_stop_ticks
    risk_one_lot = stop_dist * mult
    risk_pct_1lot = (risk_one_lot / cap * 100) if cap > 0 else 999.0

    can_margin = cap >= min_capital
    can_risk = cap > 0 and risk_one_lot <= cap * 0.01

    if can_margin and can_risk:
        status, label = "ok", "推荐"
    elif can_margin:
        status, label = "margin_ok", "可开1手·止损偏宽"
    else:
        status, label = "blocked", "资金不足"

    return {
        "ths": ths,
        "name": name,
        "exchange": exchange,
        "price": round(p, 4),
        "mult": mult,
        "tick_size": tick,
        "margin_one_lot": round(margin_one, 2),
        "min_capital_one_lot": round(min_capital, 2),
        "risk_one_lot_1pct": round(risk_one_lot, 2),
        "risk_pct_1lot_at_1pct_rule": round(risk_pct_1lot, 2),
        "status": status,
        "status_label": label,
    }


def list_product_recommendations(
    capital: float,
    price_fn: Callable[[str], Optional[float]],
    *,
    max_position_pct: float = 50.0,
) -> list[dict]:
    """扫描全部品种并排序：推荐 > 可开 > 不足。"""

    def _one(product: dict) -> dict:
        ths = product["ths"]
        main_code = price_fn(ths)
        return assess_product_for_capital(
            product, capital, main_code, max_position_pct=max_position_pct
        )

    with ThreadPoolExecutor(max_workers=10) as pool:
        rows = list(pool.map(_one, PRODUCTS))
    order = {"ok": 0, "margin_ok": 1, "blocked": 2, "no_price": 3}
    rows.sort(key=lambda r: (order.get(r["status"], 9), r.get("min_capital_one_lot") or 1e18))
    return rows