"""
实时中枢特征跟踪器
Real-time Pivot Feature Tracker

定位: 观察者 — 不修改管线，只观察 bi_zs_list 中当前中枢的特征变化。
每次管线重算后调用 update()，检测 bi_count 是否增长，若增长则重新计算
shift / contraction / duration。
"""

from collections import deque
from ChanPivotClassifier import ChanPivotClassifier


class ChanPivotMonitor:
    """
    实时追踪当前中枢的结构特征。

    update() 每次管线重算后调用，对比 bi_count 判断是否有新笔加入中枢。
    若 bi_count 增长则重新计算 3 个结构特征并返回最新值。
    """

    def __init__(self, window_size: int = 10):
        self._window_size = window_size
        self._duration_history: deque[int] = deque(maxlen=window_size)
        self._current_zs_id: tuple | None = None
        self._current_bi_count: int = 0
        self._current_is_sure: bool = False
        self._current_state: dict | None = None
        self._duration_added_for_zs: set = set()  # 已加入窗口的中枢 ID

    # ------------------------------------------------------------------
    # Public API
    # ------------------------------------------------------------------

    def update(self, bi_zs_list: list) -> dict | None:
        """
        主入口：检测当前中枢特征变化。

        参数:
            bi_zs_list: 当前管线产出的笔中枢列表

        返回:
            特征 dict（有变化时），无变化返回 None
        """
        if not bi_zs_list:
            self._current_zs_id = None
            self._current_bi_count = 0
            self._current_is_sure = False
            self._current_state = None
            return None

        zs = self._find_current_zs(bi_zs_list)
        if zs is None:
            return None

        zs_id = self._make_zs_id(zs)
        bi_count = len(zs.bi_list)
        is_sure = zs.is_sure

        # 无变化 → 跳过
        if (zs_id == self._current_zs_id
                and bi_count == self._current_bi_count
                and is_sure == self._current_is_sure):
            return None

        # 中枢切换 → 将旧中枢 duration 加入窗口
        if zs_id != self._current_zs_id:
            self._maybe_add_to_history()

        self._current_zs_id = zs_id
        self._current_bi_count = bi_count
        self._current_is_sure = is_sure

        features = ChanPivotClassifier.compute_features(
            zs, list(self._duration_history)
        )

        self._current_state = {
            "zs_id": zs_id,
            "zs_index": zs.index,
            "zs_dir": str(zs.dir),
            "bi_count": bi_count,
            "is_sure": zs.is_sure,
            "zg": round(zs.zg, 6),
            "zd": round(zs.zd, 6),
            "gg": round(zs.gg, 6),
            "dd": round(zs.dd, 6),
            **features,
            "start_time": str(zs.start_time) if hasattr(zs, "start_time") and zs.start_time else None,
        }

        # 中枢刚变为已确认时，将其 duration 加入滚动窗口
        if is_sure and zs_id not in self._duration_added_for_zs:
            self._add_duration(features["duration_raw"])
            self._duration_added_for_zs.add(zs_id)

        return self._current_state

    def get_current(self) -> dict | None:
        """返回当前中枢的最新特征"""
        return self._current_state

    def get_duration_history(self) -> list[int]:
        """返回用于归一化的 duration 滚动窗口"""
        return list(self._duration_history)

    # ------------------------------------------------------------------
    # Internal
    # ------------------------------------------------------------------

    @staticmethod
    def _make_zs_id(zs) -> tuple:
        """生成中枢的稳定标识（基于首笔首K线索引，不依赖 zs.index）"""
        bi0 = zs.bi_list[0]
        return (bi0.start_klc.index,)

    @staticmethod
    def _find_current_zs(bi_zs_list: list):
        """
        找到当前活跃中枢：
        优先取最后一个 is_sure=False（形成中）的中枢，
        没有则取最后一个 is_sure=True 的中枢。
        """
        forming = None
        last_sure = None
        for zs in bi_zs_list:
            if len(zs.bi_list) < 3:
                continue
            if not zs.is_sure:
                forming = zs
            else:
                last_sure = zs
        return forming if forming is not None else last_sure

    def _add_duration(self, duration_raw: int):
        """将已确认中枢的 duration 加入滚动窗口"""
        self._duration_history.append(duration_raw)

    def _maybe_add_to_history(self):
        """旧中枢切换前，若已确认且未记录过，则将其 duration 加入窗口"""
        if (self._current_state and self._current_state["is_sure"]
                and self._current_zs_id not in self._duration_added_for_zs):
            self._add_duration(self._current_state["duration_raw"])
            self._duration_added_for_zs.add(self._current_zs_id)