"""趋势策略委托簿，对应 Go 客户端的 ``logic/order.go``。"""

from __future__ import annotations

import secrets
from dataclasses import dataclass
from datetime import datetime, timedelta
from threading import Lock
from typing import Any

from sdk import ORDER_SIDE_BY_OFFSET, Client, OrderItem

# 表示委托仍在处理、可能继续成交的 QMT 状态。
BUSY_STATUSES = {"48", "49", "50", "51", "52", "55"}


@dataclass(frozen=True, slots=True)
class PlaceOrderRequest:
    """``OrderBook.place`` 提交委托所需的全部参数。"""

    client: Any
    op: int
    code: str
    volume: int
    order_id: str
    strategy_name: str


class OrderBook:
    """线程安全的活动委托缓存。"""

    def __init__(self, lock_timeout_sec: float = 180, cancel_timeout_sec: float = 10) -> None:
        self.lock_timeout_sec = max(0.0, float(lock_timeout_sec))
        self.cancel_timeout_sec = timedelta(seconds=cancel_timeout_sec)
        self.data: dict[str, OrderItem] = {}
        self.lock: dict[str, float] = {}
        self.mutex = Lock()

    @staticmethod
    def new_order_id(leg: str) -> str:
        """生成短订单号，为 QMT 备注中的信号键预留空间。"""
        return f"zt-{leg[:1]}-{secrets.token_hex(4)}"

    def busy(self, code: str, side: str) -> bool:
        """判断证券是否存在仍在处理中的同方向委托。"""
        with self.mutex:
            self._clear_expired_locks(datetime.now().timestamp())
            key = f"{side}-{code}"
            return key in self.lock

    def refresh(self, client: Client) -> None:
        """从 QMT 刷新当前委托明细和方向索引。"""
        orders = client.trade_detail_data("order")
        parsed_orders = [(f"{item.side}-{item.code}", item) for item in orders]
        now_timestamp = datetime.now().timestamp()
        with self.mutex:
            self.data = {key: item for key, item in parsed_orders}
            self.lock = {
                key: (
                    item.created_at.timestamp()
                    if item.created_at is not None
                    else now_timestamp
                )
                for key, item in parsed_orders
                if item.status in BUSY_STATUSES
            }
            self._clear_expired_locks(now_timestamp)

    def cancel_expired(self, client: Any, now: datetime | None = None) -> None:
        """尝试撤销超过有效期且具有委托编号的订单。"""
        self.refresh(client)
        current = now or datetime.now()

        # 使用快照遍历，避免网络调用期间长期持有互斥锁。
        for order in list(self.data.values()):
            if (
                order.created_at is not None
                and order.status in {"49", "50", "51", "52"}
                and current - order.created_at > self.cancel_timeout_sec
                and order.id
            ):
                client.cancel_by_id(order.id)

    def place(self, request: PlaceOrderRequest) -> bool:
        """按最新价提交委托，并立即写入本地方向锁。"""
        result = request.client.passorder_latest_tagged(
            request.op,
            request.code,
            request.volume,
            request.strategy_name,
            request.order_id,
        )
        if not isinstance(result, dict):
            return False
        order_ref = str(result.get("order_ref") or "").strip().lower()
        if result.get("status") != "success" or order_ref in {"", "unknown", "none"}:
            return False

        side = ORDER_SIDE_BY_OFFSET.get(str(request.op), "")
        pending = OrderItem(
            id=order_ref,
            code=request.code,
            side=side,
            remark=request.order_id,
            status="48",
            created_at=datetime.now(),
            volume=request.volume,
            local_order_id=request.order_id,
        )
        with self.mutex:
            key = f"{side}-{request.code}"
            self.data[key] = pending
            self.lock[key] = pending.created_at.timestamp()
        return True

    def _clear_expired_locks(self, now_timestamp: float) -> None:
        """清理过期方向锁；调用方必须已持有 ``mutex``。"""
        expired = [
            key
            for key, created_at in self.lock.items()
            if now_timestamp - created_at >= self.lock_timeout_sec
        ]
        for key in expired:
            self.lock.pop(key, None)