# -*- coding: utf-8 -*-
"""
账本服务: 成交回放 · 对账 · 除权 · 日终结算 (设计 §4「生命线」)
================================================================
纯逻辑在 app/core/recon.py, 本模块只负责取数、落库与状态推进。

摊薄成本口径 (与 core/cushion.PositionCost 等价, 但数据来自批次表):
    cum_buy  = Σ (剩余数量 + 已核销数量) × 开仓价
    cum_sell = Σ 已核销数量 × 核销均价
    avg_cost = max(0, (cum_buy − cum_sell) / 当前持股数)
  做T利润通过 T0 批次的买卖流水自然摊入上式, 故 **不再另行扣减** realized_t_profit
  (该列仅作展示统计, 重复扣减会把成本做低两次)。

铁律: 对账以下游为准; 修正一律走 RECON 批次留痕; 连续 N 日不一致升级 ERROR。
"""
from __future__ import annotations

import logging
from datetime import datetime, timedelta

from app.core import cushion as cu
from app.core import recon as rc
from app.core import tradedays as td
from app.repo import downstream_repo, pms_repo
from app.services import market, param_store, portfolio

logger = logging.getLogger("pms.ledger")

CURSOR_KEY = "PMS_REPLAY_CURSOR"
CURSOR_ALL = "ALL"          # 游标设成这个值 = 显式要求从头全量回放 (见 _seed_cursor)
STREAK_KEY = "PMS_RECON_STREAK"
LIVE_INSTR = ("DISPATCHED", "JUDGE_PASSED", "RULE_PASSED")


# ================================================================ 回放
def _seed_cursor(out: dict) -> dict:
    """首次回放: 把游标对齐到当前最新成交, **不追认历史**。

    `trading_order` 里躺着旧系统多年的成交记录。PMS 刚上线时一条在途指令都没有, 若从头
    回放, 每一条历史成交都会被判成「外部成交」并入 BASE 批次 —— 账本上凭空长出一堆早就
    清掉的持仓, 摊薄成本与安全垫全错, 日志还刷几百条 EXTERNAL_FILL 告警。而安全垫是补仓、
    盈利加仓、保垫减仓共同的判断依据, 它一错整条纪律链跟着错。**账本必须从干净的起点开始。**

    要补历史有两条路 (页面「参数设置」改 PMS_REPLAY_CURSOR):
      * 设成某个 order_id  → 从它之后开始回放
      * 设成 ALL           → 从头全量回放
    """
    try:
        anchor = downstream_repo.latest_filled_order_id()
    except Exception as e:
        out.update({"ok": False, "errors": [f"读下游最新成交失败: {type(e).__name__}: {e}"]})
        return out
    if not anchor:
        out["note"] = "下游暂无已成交单, 游标待下次再对齐"
        return out
    pms_repo.set_param(CURSOR_KEY, anchor, updated_by="system")
    out.update({"cursor": anchor, "seeded": True})
    out["note"] = (f"首次回放: 游标已对齐到当前最新成交 {anchor}, **不追认历史** —— "
                   f"账本从现在起跟踪。需要补历史请在页面把 PMS_REPLAY_CURSOR 改成某个 "
                   f"order_id (从它之后开始) 或 {CURSOR_ALL} (从头全量)")
    logger.warning("[replay_fills] %s", out["note"])
    return out


def replay_fills(*, limit: int = 500) -> dict:
    """增量回放 trading_order 已成交单 → 批次入账 (每 5 分钟一跳, 幂等)。"""
    out = {"ok": True, "fills": 0, "actions": 0, "alerts": [], "errors": [], "cursor": None}
    cursor = pms_repo.get_param(CURSOR_KEY)
    if not cursor:                       # 从未设过 (或被清空) —— 冷启动, 只对齐游标不入账
        return _seed_cursor(out)
    if str(cursor).strip().upper() == CURSOR_ALL:
        cursor = None                    # 显式要求从头全量回放
    try:
        fills = downstream_repo.fetch_filled_orders(since_id=cursor, limit=limit)
    except Exception as e:
        out.update({"ok": False, "errors": [f"读 trading_order 失败: {type(e).__name__}: {e}"]})
        return out
    out["fills"] = len(fills)
    if not fills:
        out["cursor"] = cursor
        return out

    try:
        instrs = _open_instructions()
    except Exception as e:
        instrs = []
        out["errors"].append(f"读在途指令失败(按外部成交处理): {e}")

    mapped = rc.map_fills_to_book(fills, instrs)
    for act in mapped["actions"]:
        try:
            _apply_action(act)
            out["actions"] += 1
        except Exception as e:
            logger.exception("入账失败 %s", act)
            out["errors"].append(f"{act.get('ts_code')} 入账失败: {type(e).__name__}: {e}")
    out["alerts"] = mapped["alerts"]

    for code in {a["ts_code"] for a in mapped["actions"]}:
        try:
            recompute_position(code)
        except Exception as e:
            out["errors"].append(f"{code} 成本重算失败: {e}")

    try:
        nc = rc.next_cursor(fills, cursor)
        pms_repo.set_param(CURSOR_KEY, nc, "system")
        out["cursor"] = nc
    except Exception as e:
        out["errors"].append(f"游标推进失败: {e}")
    out["ok"] = not out["errors"]
    for a in out["alerts"]:
        logger.warning("[回放告警] %s", a.get("message"))
    return out


def _open_instructions() -> list:
    """在途指令 (回放认领的候选池)。

    dispatched_at 取「下发时点 → 建单时点」, **不用 updated_at**:
    updated_at 每次部分成交回写都会往前跳, 拿它当下发时点会让同一条指令的后续成交
    被时间守卫挡在门外, 误判成外部成交。建单时点是天然的下界, 宁松勿紧。
    """
    rows = pms_repo.list_instructions(statuses=list(LIVE_INSTR), limit=500)
    out = []
    for r in rows:
        prog = r.get("progress") or {}
        out.append({"instruction_id": r["instruction_id"], "ts_code": r["ts_code"],
                    "side": r.get("side"), "qty": int(r.get("qty") or 0),
                    "exec_qty": int(r.get("exec_qty") or 0), "action": r.get("action"),
                    "dispatched_at": str(prog.get("dispatched_at")
                                         or r.get("created_at") or "")})
    return out


def _apply_action(act: dict):
    code, qty, px = act["ts_code"], int(act["qty"]), float(act["price"] or 0)
    if qty <= 0:
        return
    pms_repo.ensure_position(code)
    if act["kind"] == "BUY":
        pms_repo.insert_lot(ts_code=code, lot_type=act.get("lot_type") or "BASE", qty=qty,
                            open_price=px, open_date=datetime.now().date(),
                            instruction_id=act.get("instruction_id"),
                            note="外部成交并入 BASE" if not act.get("instruction_id") else None)
        pms_repo.bump_position_qty(code, total_delta=qty, avail_delta=0)   # T+1: 当日买入不可卖
    else:
        lots = pms_repo.list_lots(code, status="OPEN")
        res = rc.apply_sell_to_lots(
            [{"lot_id": l["id"], "lot_type": l["lot_type"], "qty": int(l["qty"]),
              "open_date": _date_key(l["open_date"])} for l in lots], qty)
        by_id = {l["id"]: l for l in lots}
        t_profit = 0.0
        for a in res["alloc"]:
            lot = by_id[a["lot_id"]]
            pnl = (px - float(lot["open_price"] or 0)) * a["qty"]
            pms_repo.close_lot_qty(a["lot_id"], qty=a["qty"], close_price=px, realized_pnl=pnl)
            if lot["lot_type"] == "T0":
                t_profit += pnl
        pms_repo.bump_position_qty(code, total_delta=-qty, avail_delta=-qty)
        if t_profit:
            pos = pms_repo.get_position(code) or {}
            pms_repo.update_position(
                code, realized_t_profit=float(pos.get("realized_t_profit") or 0) + t_profit)
        for al in res["alerts"]:
            logger.warning("[卖出核销] %s %s", code, al.get("message"))
    if act.get("instruction_id"):
        try:
            pms_repo.add_instruction_exec(act["instruction_id"], qty)
            _settle_instruction(act["instruction_id"])
        except Exception as e:
            logger.warning("指令进度更新失败 %s: %s", act["instruction_id"], e)


def _settle_instruction(instruction_id: str):
    """成交量达到指令数量 → 置 CONFIRMED (部分成交保持在途, 由窗口/过期规则收口)。"""
    ins = pms_repo.get_instruction(instruction_id)
    if ins and int(ins.get("exec_qty") or 0) >= int(ins.get("qty") or 0) > 0:
        pms_repo.update_instruction(instruction_id, status="CONFIRMED")


def _date_key(d):
    try:
        return int(str(d).replace("-", "")[:8])
    except (TypeError, ValueError):
        return 0


def recompute_position(ts_code: str) -> dict:
    """由批次表重算持仓数量/摊薄成本/安全垫/垫子峰值。"""
    lots = pms_repo.list_lots(ts_code, status=None, limit=2000)
    qty = sum(int(l["qty"] or 0) for l in lots)
    cum_buy = sum((int(l["qty"] or 0) + int(l["closed_qty"] or 0)) * float(l["open_price"] or 0)
                  for l in lots)
    cum_sell = sum(int(l["closed_qty"] or 0) * float(l["close_avg_price"] or 0) for l in lots)
    by_type = {}
    for l in lots:
        if int(l["qty"] or 0) > 0:
            by_type[l["lot_type"]] = by_type.get(l["lot_type"], 0) + int(l["qty"])

    avg_cost = max(0.0, (cum_buy - cum_sell) / qty) if qty > 0 else None
    px = market.get_price(ts_code) or avg_cost or 0
    cp = (px / avg_cost - 1.0) if (avg_cost and avg_cost > 0 and px) else None
    solid = param_store.get_float("PMS_CUSHION_SOLID", 0.03)
    pos = pms_repo.get_position(ts_code) or {}
    peak = max(float(pos.get("cushion_peak") or 0), cp or 0)
    scale = param_store.get_float("PMS_TOTAL_SCALE", 0)

    fields = {
        "total_qty": qty, "base_qty": by_type.get("BASE", 0) + by_type.get("RECON", 0),
        "fill_qty": by_type.get("FILL", 0), "add_qty": by_type.get("ADD", 0),
        "dca_qty": by_type.get("DCA", 0), "t0_qty": by_type.get("T0", 0),
        "avg_cost": round(avg_cost, 3) if avg_cost else None,
        "cushion_pct": round(cp, 4) if cp is not None else None,
        "cushion_state": cu.cushion_state(cp, solid), "cushion_peak": round(peak, 4),
        "pct_of_scale": round(qty * px / scale, 4) if scale > 0 else None,
        "status": "CLOSED" if qty <= 0 else (pos.get("status") or "HOLDING"),
    }
    if qty > 0 and (pos.get("status") in (None, "PLANNED", "CLOSED")):
        fields["status"] = "HOLDING"
    if qty > 0 and not pos.get("opened_date"):
        fields["opened_date"] = datetime.now().date()
    pms_repo.update_position(ts_code, **fields)
    return fields


# ================================================================ 对账
def reconcile(*, apply_fix: bool = True) -> dict:
    """账本 vs 下游持仓, 以下游为准修正并留痕。"""
    out = {"ok": True, "diffs": [], "fixes": [], "errors": [], "columns": {}, "severity": rc.SEV_OK}
    try:
        ds = downstream_repo.fetch_positions()
    except Exception as e:
        out.update({"ok": False, "errors": [f"读 trading_position 失败: {type(e).__name__}: {e}"]})
        return out
    out["columns"] = ds["columns"]
    if ds["rows"] and ds["columns"].get("qty") is None:
        out.update({"ok": False, "errors": [
            "下游持仓表未识别出数量列 —— 请按 QMT_INTERFACE_REQUIREMENTS A1/D1 取得 DDL 后, "
            "把列名补进 downstream_repo.QTY_CANDIDATES"]})
        return out

    book = [{"ts_code": r["ts_code"], "total_qty": int(r.get("total_qty") or 0)}
            for r in pms_repo.list_positions()]
    diffs = rc.diff_positions(book, [{"ts_code": r["ts_code"], "qty": r["qty"]}
                                     for r in ds["rows"]])
    out["diffs"] = diffs

    streak = param_store.get_int(STREAK_KEY, 0)
    streak = streak + 1 if diffs else 0
    # 必须走 ParamStore 写入: 直接写库不会失效缓存, 会导致连续天数一直读到旧值
    param_store.set_param(STREAK_KEY, streak, "system")
    out["severity"] = rc.recon_severity(streak if diffs else 0,
                                        param_store.get_int("PMS_RECON_ALARM_DAYS", 3))

    if not diffs or not apply_fix:
        return out

    codes = [d["ts_code"] for d in diffs]
    prices = market.get_prices(codes)
    lots_map = {c: [{"lot_id": l["id"], "lot_type": l["lot_type"], "qty": int(l["qty"]),
                     "open_date": _date_key(l["open_date"])}
                    for l in pms_repo.list_lots(c, status="OPEN")] for c in codes}
    fixes = rc.build_recon_fixes(diffs, price_map=prices, lots_map=lots_map)
    for f in fixes:
        try:
            _apply_fix(f)
            recompute_position(f["ts_code"])
        except Exception as e:
            logger.exception("对账修正失败 %s", f)
            out["errors"].append(f"{f['ts_code']} 修正失败: {type(e).__name__}: {e}")
    out["fixes"] = fixes
    out["ok"] = not out["errors"]
    if out["severity"] == rc.SEV_ERROR:
        logger.error("[对账] 连续 %s 日不一致, 升级 ERROR 待人工: %s 项差异", streak, len(diffs))
    return out


def _apply_fix(f: dict):
    code = f["ts_code"]
    pms_repo.ensure_position(code)
    if f["op"] == "ADD_RECON_LOT":
        px = float(f.get("price") or 0)
        pms_repo.insert_lot(ts_code=code, lot_type="RECON", qty=int(f["qty"]),
                            open_price=px, open_date=datetime.now().date(),
                            note=f["note"] + ("" if px > 0 else " [缺现价, 成本待人工核]"))
    else:
        lots = {l["id"]: l for l in pms_repo.list_lots(code, status="OPEN")}
        px = float(f.get("price") or 0)
        for a in f.get("alloc") or []:
            lot = lots.get(a["lot_id"])
            pnl = (px - float(lot["open_price"] or 0)) * a["qty"] if (lot and px) else 0.0
            pms_repo.close_lot_qty(a["lot_id"], qty=a["qty"], close_price=px or
                                   float(lot["open_price"] or 0), realized_pnl=pnl)
    pms_repo.insert_ledger(ts_code=code, action="RECON", arbiter="rule", verdict="PASS",
                           price_at=float(f.get("price") or 0),
                           hard_numbers={"op": f["op"], "qty": f["qty"]},
                           reason=f["note"])


# ================================================================ 除权
def detect_and_apply_ex_right() -> dict:
    """用昨日结算快照与今日持仓/价格比对, 识别送转股并按比例调整批次。"""
    out = {"checked": 0, "ex_rights": [], "mismatches": [], "errors": []}
    prev = _prev_snapshot()
    if not prev:
        out["errors"].append("无昨日结算快照, 本次跳过除权检测 (次日起生效)")
        return out
    for pos in pms_repo.list_positions(only_open=True):
        code = pos["ts_code"]
        old = prev.get(code)
        if not old:
            continue
        out["checked"] += 1
        px = market.get_price(code)
        r = rc.detect_ex_right(int(old.get("qty") or 0), int(pos.get("total_qty") or 0),
                               float(old.get("price") or 0), float(px or 0))
        if not r:
            continue
        if r["kind"] == "EX_RIGHT":
            try:
                lots = pms_repo.list_lots(code, status="OPEN")
                for l in rc.apply_ex_right(lots, r["ratio"]):
                    pms_repo.update_lot(l["id"], qty=l["qty"], open_price=l["open_price"],
                                        note=l["note"])
                recompute_position(code)
                pms_repo.insert_ledger(ts_code=code, action="RECON", arbiter="rule",
                                       verdict="PASS", price_at=px or 0, hard_numbers=r,
                                       reason=f"除权调整 ×{r['ratio']}")
                out["ex_rights"].append({"ts_code": code, **r})
            except Exception as e:
                out["errors"].append(f"{code} 除权调整失败: {e}")
        else:
            out["mismatches"].append({"ts_code": code, **r})
            logger.error("[除权] %s 比例不吻合, 待人工: %s", code, r.get("reason"))
    return out


def _prev_snapshot() -> dict:
    """取最近一份日终快照 {code: {qty, price}} (存在 pms_daily_report 里, 不新增表)。"""
    r = pms_repo.latest_report()
    if not r:
        return {}
    snap = (r.get("report") or {}).get("snapshot") or {}
    return snap if isinstance(snap, dict) else {}


# ================================================================ 盘前 / 日终
def premarket() -> dict:
    """盘前准备 (08:50): T+1 可卖重置、参考位取数、刹车结算。"""
    out = {"ok": True, "avail_reset": 0, "refs": 0, "brake": None, "errors": []}
    try:
        out["avail_reset"] = pms_repo.reset_avail_all()
    except Exception as e:
        out["errors"].append(f"可卖量重置失败: {e}")
    for pos in pms_repo.list_positions(only_open=True):
        code = pos["ts_code"]
        try:
            refs = market.get_refs(code, base_cost=pos.get("avg_cost"))
            pms_repo.update_position(code, support_ref=refs.get("support"),
                                     pressure_ref=refs.get("pressure"),
                                     stop_ref=refs.get("stop"),
                                     ref_source=refs.get("source"))
            out["refs"] += 1
        except Exception as e:
            out["errors"].append(f"{code} 参考位取数失败: {e}")
    try:
        out["brake"] = _settle_brake()
    except Exception as e:
        out["errors"].append(f"刹车结算失败: {e}")
    out["ok"] = not out["errors"]
    return out


def _settle_brake() -> dict:
    """组合刹车: 自高水位回撤 ≥ 阈值 → 自主增持停 N 个交易日 (命令类不受限)。"""
    v = portfolio.positions_view()
    mv = v["totals"]["portfolio_mv"]
    hw = param_store.get_float("PMS_HIGH_WATER", 0.0)
    dd_limit = param_store.get_float("PMS_BRAKE_DRAWDOWN", 0.05)
    days = param_store.get_int("PMS_BRAKE_DAYS", 3)
    until = param_store.get_int("PMS_BRAKE_UNTIL", 0)
    today = td.ymd()
    if mv > hw:
        param_store.set_param("PMS_HIGH_WATER", mv, "system")
        hw = mv
    drawdown = (1 - mv / hw) if hw > 0 else 0.0
    if hw > 0 and drawdown >= dd_limit and today >= until:
        until = td.ymd(td.next_trade_day(datetime.now().date(), days))
        param_store.set_param("PMS_BRAKE_UNTIL", until, "system")
        logger.warning("[刹车] 自高水位回撤 %.1f%% ≥ %.0f%%, 自主增持暂停至 %s",
                       drawdown * 100, dd_limit * 100, until)
    return {"high_water": hw, "portfolio_mv": mv, "drawdown": round(drawdown, 4),
            "brake_until": until, "active": today < until}


def daily_settle() -> dict:
    """日终结算 (15:10): 除权检测 → 全量对账 → 垫子峰值/连负天数 → 命令进度日结 → 快照留存。"""
    from app.services import command_service
    out = {"ok": True, "steps": {}, "errors": []}
    try:
        out["steps"]["ex_right"] = detect_and_apply_ex_right()
    except Exception as e:
        out["errors"].append(f"除权检测失败: {e}")
    try:
        out["steps"]["recon"] = reconcile()
    except Exception as e:
        out["errors"].append(f"对账失败: {e}")
    try:
        out["steps"]["cushion"] = _settle_cushion()
    except Exception as e:
        out["errors"].append(f"安全垫结算失败: {e}")
    try:
        out["steps"]["commands"] = command_service.refresh_progress()
    except Exception as e:
        out["errors"].append(f"命令进度结算失败: {e}")
    try:
        pms_repo.expire_proposals()
    except Exception as e:
        out["errors"].append(f"提议过期处理失败: {e}")
    out["ok"] = not out["errors"]
    return out


def _settle_cushion() -> dict:
    """更新垫子峰值与「安全垫连续为负天数」(清弱票判定所需)。"""
    v = portfolio.positions_view()
    streak = portfolio.neg_streak_map()
    updated = 0
    for x in v["held"]:
        code, cp = x["ts_code"], x["cushion_pct"]
        streak[code] = (int(streak.get(code, 0)) + 1) if (cp is not None and cp < 0) else 0
        peak = max(float(x["cushion_peak"] or 0), cp or 0)
        pms_repo.update_position(code, cushion_pct=cp, cushion_peak=round(peak, 4),
                                 cushion_state=x["cushion_state"])
        updated += 1
    held = {x["ts_code"] for x in v["held"]}
    portfolio.save_neg_streak({k: v2 for k, v2 in streak.items() if k in held})
    return {"updated": updated,
            "neg_streak": {k: v2 for k, v2 in streak.items() if v2 > 0 and k in held}}


# ================================================================ 日报
def build_daily_report(ymd: int = None) -> dict:
    """运营日报 (15:30): 关注区 + 全量统计 + 当日快照 (快照供次日除权检测)。"""
    from app.services import command_service
    ymd = int(ymd or td.ymd())
    v = portfolio.positions_view()
    t = v["totals"]
    try:
        recon_state = {"streak": param_store.get_int(STREAK_KEY, 0)}
    except Exception:
        recon_state = {}

    cmds = pms_repo.list_commands(statuses=["EXECUTING", "PARTIAL", "PENDING", "PLANNING"],
                                  limit=100)
    proposals = pms_repo.list_proposals(statuses=("WAIT_USER",), limit=100)
    live_ins = pms_repo.list_instructions(statuses=list(LIVE_INSTR), limit=200)
    attention = []
    for c in cmds:
        prog = c.get("progress") or {}
        attention.append({"type": "命令进度", "command_id": c["command_id"],
                          "cmd_type": c["cmd_type"], "status": c["status"],
                          "done": prog.get("done_amount"), "target": prog.get("target_amount"),
                          "deadline": prog.get("deadline")})
    if proposals:
        attention.append({"type": "待确认提议", "count": len(proposals)})
    if recon_state.get("streak"):
        attention.append({"type": "对账差异", "streak": recon_state["streak"],
                          "severity": rc.recon_severity(
                              recon_state["streak"],
                              param_store.get_int("PMS_RECON_ALARM_DAYS", 3))})
    brake_until = param_store.get_int("PMS_BRAKE_UNTIL", 0)
    if brake_until > ymd:
        attention.append({"type": "组合刹车", "until": brake_until})
    if v["price_missing"]:
        attention.append({"type": "行情缺失", "codes": v["price_missing"]})
    if not v["sector_ready"]:
        attention.append({"type": "行业约束停用", "hint": "PMS_SECTOR_SOURCE 未配置"})
    if td.calendar_degraded():
        attention.append({"type": "交易日历降级", "hint": "未安装 chinesecalendar, 节假日不可辨"})

    report = {
        "ymd": ymd, "generated_at": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
        "totals": t, "attention": attention,
        "commands": [{"command_id": c["command_id"], "cmd_type": c["cmd_type"],
                      "status": c["status"], "progress": c.get("progress")} for c in cmds],
        "proposals": len(proposals), "live_instructions": len(live_ins),
        "positions": [{"ts_code": x["ts_code"], "qty": x["total_qty"], "price": x["price"],
                       "avg_cost": x["avg_cost"], "cushion_pct": x["cushion_pct"],
                       "cushion_state": x["cushion_state"], "mv": x["market_value"],
                       "pct_of_scale": x["pct_of_scale"]} for x in v["held"]],
        # 次日除权检测用的快照 (数量 + 收盘价)
        "snapshot": {x["ts_code"]: {"qty": x["total_qty"], "price": x["price"]}
                     for x in v["held"]},
        "recon": recon_state,
    }
    try:
        pms_repo.upsert_report(ymd, report)
    except Exception as e:
        logger.error("日报落表失败: %s", e)
        report["save_error"] = str(e)
    return report


def expire_stale_instructions() -> int:
    """下发后长时间未被接受的指令置过期 (不自动重发 —— 设计 §13)。"""
    mins = param_store.get_int("PMS_DISPATCH_EXPIRE_MIN", 30)
    cut = datetime.now() - timedelta(minutes=mins)
    n = 0
    for r in pms_repo.list_instructions(statuses=["DISPATCHED"], limit=500):
        try:
            if str(r.get("updated_at") or "") and str(r["updated_at"]) < str(cut):
                pms_repo.update_instruction(r["instruction_id"], status="EXPIRED")
                n += 1
        except Exception:
            continue
    return n