"""月度结算服务（M3 ④）：生成快照 → 提交审批 → 通过即锁定。

确认回款口径（澄清 #8 策略点，2026-10-16 暂定）：settlement_status=1 的
**有效台账行**（is_active=1、settlement_id IS NULL=未被任何月结固化），
按 settlement_month（回款日所在月）归集。答复后只改 ``_confirm_scope``。

通过即锁定（status=3 终态）：锁定后源数据（回款/发货）写路径由
``ensure_month_not_locked`` 拦截；调整走调整单（T6）。
"""

import logging
from decimal import ROUND_HALF_UP, Decimal

from sqlalchemy import select
from sqlalchemy.orm import Session

from app.core.constants import (
    MODULE_SETTLEMENT,
)
from app.core.exceptions import BadRequestError, NotFoundError
from app.models import (
    MonthlySettlement,
    Personnel,
    SettlementItem,
    User,
)
from app.models.approval import APPROVAL_TYPE_MONTHLY_SETTLEMENT
from app.models.performance_ledger import CALC_TYPE_MANAGER_AGGREGATE
from app.models.settlement import (
    SETTLEMENT_STATUS_APPROVED,
    SETTLEMENT_STATUS_DRAFT,
    SETTLEMENT_STATUS_PENDING,
    SETTLEMENT_STATUS_REJECTED,
)
from app.repositories import settlement_repository
from app.schemas.settlement import (
    SettlementDetailOut,
    SettlementOut,
    SettlementQuery,
)
from app.services import approval_service, audit_service
from app.services.approval_service import AuditRecord, RequestMeta
from app.services.formula import manager_team_share, monthly_salary

logger = logging.getLogger(__name__)

# 审批对象类型引用（order_type=2 月结、3 调整单）
_SETTLEMENT_ORDER_TYPE = APPROVAL_TYPE_MONTHLY_SETTLEMENT
_SETTLEMENT_NOTE = "确认回款口径（#8 策略点）：settlement_status=1 的有效台账行按回款日归月"


def generate(
    session: Session,
    month: str,
    *,
    operator: User,
    meta: RequestMeta | None = None,
) -> SettlementOut:
    """生成月度结算快照（草稿）：按确认回款口径取有效台账行，按人汇总。

    - 同月已有月结行（任意状态）时 400——一行一月，重生成走「驳回/草稿态
      重新生成」（先清 items 重算头表）
    - 经理聚合（calc_type=2）在生成时计算（#12 暂口径：基数不含经理个人户）
    """
    with audit_service.audit(
        session,
        operator=operator,
        record=AuditRecord(
            module=MODULE_SETTLEMENT,
            action="生成月结",
            summary=f"生成 {month} 月度结算快照",
            request_data={"month": month},
        ),
        meta=meta,
    ):
        existing = settlement_repository.get_by_month(session, month)
        if existing is not None:
            if existing.status == SETTLEMENT_STATUS_APPROVED:
                raise BadRequestError(f"{month} 已审定锁定，不可重新生成（调整走调整单）")
            if existing.status == SETTLEMENT_STATUS_PENDING:
                raise BadRequestError(f"{month} 有待审批的月结，不可重新生成")
            # 草稿/已驳回：允许重新生成（清明细重算）

        ledger_rows = _confirm_scope(session, month)
        if not ledger_rows:
            raise BadRequestError(f"{month} 无可结算的核算记录（先在台账完成核算）")

        # 经理团队聚合（#12 策略点：基数不含经理个人户业绩）
        aggregate_rows = _build_manager_aggregates(session, ledger_rows, month)

        settlement = settlement_repository.get_by_month(session, month)
        is_new = settlement is None
        if is_new:
            settlement = MonthlySettlement(
                settlement_month=month,
                submitter_id=operator.id,
                submitter_name=operator.username,
                status=SETTLEMENT_STATUS_DRAFT,
            )
            settlement_repository.add(session, settlement)
        else:
            settlement.submitter_id = operator.id
            settlement.submitter_name = operator.username
            settlement.status = SETTLEMENT_STATUS_DRAFT

        # 按人汇总（台账行：personnel+calc_type 维度）
        by_person: dict[tuple[int, int], dict] = {}
        for row in ledger_rows + aggregate_rows:
            key = (row.personnel_id, row.calc_type)
            bucket = by_person.setdefault(
                key,
                {
                    "personnel_id": row.personnel_id,
                    "personnel_name": row.personnel_name,
                    "role_code": row.role_code,
                    "calc_type": row.calc_type,
                    "performance_sum": Decimal("0"),
                    "payable_sum": Decimal("0"),
                    "ledger_ids": [],
                    "is_probation": row.is_probation,
                },
            )
            bucket["performance_sum"] += row.performance_amount or Decimal("0")
            bucket["payable_sum"] += row.payable_amount or Decimal("0")
            bucket["ledger_ids"].append(row.id)

        items: list[SettlementItem] = []
        for (_, _), bucket in sorted(by_person.items()):
            person = session.get(Personnel, bucket["personnel_id"])
            basic = person.salary_standard if person else None
            mode = _salary_mode_of(session, bucket["role_code"])
            net = (
                monthly_salary(bucket["payable_sum"], basic, mode)
                if person and person.is_probation != 1
                else None
            )
            note = None
            if person and person.is_probation == 1:
                note = (
                    f"试用期绩效照算不发放；年累计超 {_probation_threshold(session)} 元部分"
                    "年底一次性结算"
                )
            items.append(
                SettlementItem(
                    personnel_id=bucket["personnel_id"],
                    personnel_name=bucket["personnel_name"],
                    role_code=bucket["role_code"],
                    calc_type=bucket["calc_type"],
                    performance_sum=bucket["performance_sum"].quantize(
                        Decimal("0.01"), rounding=ROUND_HALF_UP
                    ),
                    payable_sum=bucket["payable_sum"].quantize(
                        Decimal("0.01"), rounding=ROUND_HALF_UP
                    ),
                    basic_amount=basic,
                    salary_mode=mode,
                    net_amount=(
                        net.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
                        if net is not None
                        else None
                    ),
                    is_probation=bucket["is_probation"],
                    probation_note=note,
                    snapshot_json={"ledger_ids": bucket["ledger_ids"]},
                )
            )

        settlement_repository.replace_items(session, settlement.id, items)
        settlement.total_performance = sum(
            (i.performance_sum for i in items), Decimal("0")
        ).quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
        settlement.total_payable = sum((i.payable_sum for i in items), Decimal("0")).quantize(
            Decimal("0.01"), rounding=ROUND_HALF_UP
        )
        settlement.person_count = len({i.personnel_id for i in items})
        settlement.snapshot_json = {"note": _SETTLEMENT_NOTE}
        session.commit()
        logger.info("月结生成 | month=%s | items=%s", month, len(items))
        return _detail_of(session, settlement)


def submit(
    session: Session,
    settlement_id: int,
    *,
    operator: User,
    meta: RequestMeta | None = None,
) -> SettlementDetailOut:
    """提交审批：开关分流（关=自动通过并锁定；开=待财务复核）。"""
    with audit_service.audit(
        session,
        operator=operator,
        record=AuditRecord(
            module=MODULE_SETTLEMENT,
            action="提交月结",
            summary=f"提交月结 #{settlement_id}",
            request_data={"settlement_id": settlement_id},
        ),
        meta=meta,
    ):
        settlement = settlement_repository.get_by_id(session, settlement_id)
        if settlement is None:
            raise NotFoundError("月结不存在")
        if settlement.status not in (SETTLEMENT_STATUS_DRAFT, SETTLEMENT_STATUS_REJECTED):
            raise BadRequestError("仅草稿或已驳回状态可提交")

        order = approval_service.submit_order(
            session,
            order_type=_SETTLEMENT_ORDER_TYPE,
            ref_id=settlement.id,
            refer_no=f"JS{settlement.settlement_month.replace('-', '')}",
            submitter=operator,
        )
        settlement.approval_order_no = order.order_no
        if order.status == SETTLEMENT_STATUS_APPROVED:
            mark_locked(session, settlement, operator=operator)
            session.commit()
            logger.info("月结自动通过并锁定 | %s", settlement.settlement_month)
            return _detail_of(session, settlement)

        settlement.status = SETTLEMENT_STATUS_PENDING
        session.commit()
        return _detail_of(session, settlement)


def mark_locked(session: Session, settlement: MonthlySettlement, *, operator: User) -> None:
    """审批通过钩子（由 approval_service.act 回调）：置已审定+锁定信息。"""
    from datetime import datetime

    settlement.status = SETTLEMENT_STATUS_APPROVED
    settlement.locked_at = datetime.now()
    settlement.locked_by = operator.username


def mark_rejected(session: Session, settlement: MonthlySettlement, *, operator: User) -> None:
    """审批驳回钩子：回草稿（可修改后重提）。

    锁定信息一并清空：草稿态残留 locked_at/locked_by 会让详情页展示
    「已锁定」的假象（历史缺陷路径下驳回前可能已被提前锁定）。
    """
    settlement.status = SETTLEMENT_STATUS_DRAFT
    settlement.locked_at = None
    settlement.locked_by = None


def ensure_month_not_locked(session: Session, month: str) -> None:
    """锁定拦截（回款/发货写路径调用）：单据日期所在月已审定 → 400。"""
    settlement = settlement_repository.get_by_month(session, month)
    if settlement is not None and settlement.status == SETTLEMENT_STATUS_APPROVED:
        raise BadRequestError(f"{month} 已月结锁定，源数据不可修改（调整走调整单）")


def get_detail(session: Session, settlement_id: int) -> SettlementDetailOut:
    settlement = settlement_repository.get_by_id(session, settlement_id)
    if settlement is None:
        raise NotFoundError("月结不存在")
    return _detail_of(session, settlement)


def list_page(session: Session, query: SettlementQuery):
    from app.core.response import PageResult
    from app.schemas.settlement import SettlementOut

    rows = settlement_repository.list_settlements(session, query)
    total = settlement_repository.count_settlements(session, query)
    return PageResult[SettlementOut](
        records=[SettlementOut.model_validate(r) for r in rows],
        total=total,
        page_num=query.page_num,
        page_size=query.page_size,
    )


# ---------- 内部 ----------


def _confirm_scope(session: Session, month: str) -> list:
    """确认回款口径（#8 策略点）：本月有效台账行（未入结）。"""
    from app.models import PerformanceLedger

    return list(
        session.execute(
            select(PerformanceLedger)
            .where(
                PerformanceLedger.settlement_month == month,
                PerformanceLedger.is_active == 1,
                PerformanceLedger.settlement_id.is_(None),
            )
            .order_by(PerformanceLedger.id)
        ).scalars()
    )


def _build_manager_aggregates(session: Session, ledger_rows: list, month: str) -> list:
    """按经理生成团队聚合行（calc_type=2）。

    #12 策略点：聚合基数**不含**经理个人户业绩（customer_type=
    manager_personal 的行按经理个人户单笔处理，已落台账但此处不入基数）。
    经理 = 本月台账行里 role_code=sales_manager 且 customer_type=personal
    的人员（本人带领的业务员经 manager_id 关联）。
    """
    from app.models import PerformanceLedger

    managers: dict[int, dict] = {}
    for row in ledger_rows:
        if row.customer_type == "manager_personal":
            continue  # 经理个人户业绩不入聚合基数（#12 暂口径）
        # 找到该行业务归属人员的经理（manager_id）
        person = session.get(Personnel, row.personnel_id)
        manager_id = person.manager_id if person else None
        if manager_id is None:
            continue
        bucket = managers.setdefault(
            manager_id,
            {
                "performance": Decimal("0"),
                "business_id": row.business_id,
                "business_no": row.business_no,
                "names": set(),
            },
        )
        bucket["performance"] += row.performance_amount or Decimal("0")
        bucket["names"].add(row.personnel_name)

    from datetime import date

    from app.repositories import business_role_repository
    from app.services.param_service import parse_fraction, resolve_snapshot

    aggregates: list = []
    snapshot = resolve_snapshot(session, date.today())
    # 参数按百分数存储（12.5 表示 12.5%）：parse_fraction 得 12.5，
    # manager_team_share 内部再 ÷100 —— 调用方不得再乘 100（否则放大 100 倍）
    team_text = snapshot.get("manager.share.team")
    company_text = snapshot.get("manager.share.company")
    team_pct = parse_fraction(team_text)
    company_pct = parse_fraction(company_text)
    for manager_id, bucket in managers.items():
        manager = session.get(Personnel, manager_id)
        if manager is None:
            continue
        role = (
            business_role_repository.get_by_id(session, manager.business_role_id)
            if manager.business_role_id
            else None
        )
        if role is None or role.role_code != "sales_manager":
            continue  # 非营销经理的上级不参与聚合
        # 全公司基数：全部非经理个人户的有效行
        company_base = sum(
            (
                r.performance_amount or Decimal("0")
                for r in ledger_rows
                if r.customer_type != "manager_personal"
            ),
            Decimal("0"),
        )
        share = manager_team_share(
            bucket["performance"],
            company_base,
            team_pct=team_pct,
            company_pct=company_pct,
        )
        member_names = "、".join(sorted(bucket["names"])) or "（无成员）"
        aggregates.append(
            PerformanceLedger(
                receipt_id=None,
                calc_type=CALC_TYPE_MANAGER_AGGREGATE,
                business_id=bucket["business_id"],
                business_no=bucket["business_no"],
                personnel_id=manager_id,
                personnel_name=manager.personnel_name,
                role_code="sales_manager",
                customer_type="personal",
                product_category="mixed",
                receipt_date=date.today(),
                # 比例原文取实际参数（勿硬编码默认值——参数调整后台账说明会失真）
                rate_text=f"聚合:{team_text}%+{company_text}%",
                converted_profit=None,
                performance_amount=share.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP),
                barter_applied=0,
                payable_amount=share.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP),
                settlement_month=month,
                is_probation=1 if manager.is_probation == 1 else 0,
                snapshot_json={
                    "team_base": str(bucket["performance"]),
                    "company_base": str(company_base),
                    "members": member_names,
                    "note": "#12 暂口径：基数不含经理个人户业绩；9.8 方案公式",
                },
            )
        )
    return aggregates


def _salary_mode_of(session: Session, role_code: str) -> str | None:
    from datetime import date

    from app.services.param_service import resolve_snapshot

    snapshot = resolve_snapshot(session, date.today())
    return snapshot.get("salary.basic.mode", role_code=role_code) or None


def _probation_threshold(session: Session) -> Decimal:
    from datetime import date

    from app.services.param_service import parse_fraction, resolve_snapshot

    snapshot = resolve_snapshot(session, date.today())
    from app.services.formula import to_decimal

    return to_decimal(parse_fraction(snapshot.get("probation.annual.threshold")))


def _detail_of(session: Session, settlement: MonthlySettlement) -> SettlementDetailOut:
    items = settlement_repository.list_items(session, settlement.id)
    detail = SettlementDetailOut.model_validate(settlement)
    from app.schemas.settlement import SettlementItemOut

    detail.items = [SettlementItemOut.model_validate(i) for i in items]
    return detail


def create_adjustment(
    session: Session,
    payload,
    *,
    operator: User,
    meta: RequestMeta | None = None,
):
    """新建调整单：开关分流（关=提交即生效留痕；开=待审批）。"""
    from app.core.constants import NO_PREFIX_ADJUSTMENT
    from app.models import AdjustmentOrder
    from app.models.approval import APPROVAL_STATUS_APPROVED, APPROVAL_TYPE_ADJUSTMENT
    from app.models.settlement import (
        ADJUSTMENT_STATUS_EFFECTIVE,
        ADJUSTMENT_STATUS_PENDING,
    )
    from app.services.no_generator import next_no

    person = session.get(Personnel, payload.personnel_id)
    if person is None:
        raise BadRequestError("调整人员不存在")

    with audit_service.audit(
        session,
        operator=operator,
        record=AuditRecord(
            module=MODULE_SETTLEMENT,
            action="新建调整单",
            summary=f"调整单 {payload.direction} {payload.amount} 元（{person.personnel_name}）",
            request_data=payload.model_dump(),
        ),
        meta=meta,
    ):
        order = AdjustmentOrder(
            order_no=next_no(
                session,
                model=AdjustmentOrder,
                column_name="order_no",
                prefix=NO_PREFIX_ADJUSTMENT,
            ),
            settlement_month=payload.settlement_month,
            personnel_id=payload.personnel_id,
            personnel_name=person.personnel_name,
            direction=payload.direction,
            amount=payload.amount,
            reason=payload.reason.strip(),
            submitter_id=operator.id,
            submitter_name=operator.username,
        )
        session.add(order)
        session.flush()

        # 开关分流与留痕统一交给 submit_order：开关关闭时它自动通过并写两条
        # 「系统」留痕。**不得手工插 ApprovalStep** —— approval_steps.order_id
        # 外键指向 approval_orders（不是 adjustment_orders），用调整单 id 落步
        # 必然外键失败（历史缺陷：关开关时新建调整单不可用）
        approval_order = approval_service.submit_order(
            session,
            order_type=APPROVAL_TYPE_ADJUSTMENT,
            ref_id=order.id,
            refer_no=order.order_no,
            submitter=operator,
        )
        order.status = (
            ADJUSTMENT_STATUS_EFFECTIVE
            if approval_order.status == APPROVAL_STATUS_APPROVED
            else ADJUSTMENT_STATUS_PENDING
        )
        session.flush()
        session.commit()
        logger.info("调整单创建 | order=%s | status=%s", order.order_no, order.status)
        return {
            "id": order.id,
            "order_no": order.order_no,
            "status": order.status,
            "personnel_name": order.personnel_name,
            "amount": str(order.amount),
            "direction": order.direction,
        }


def list_adjustments(session: Session) -> list[dict]:
    """调整单列表（月份倒序）。"""
    from sqlalchemy import select

    from app.models import AdjustmentOrder

    rows = (
        session.execute(select(AdjustmentOrder).order_by(AdjustmentOrder.id.desc()).limit(200))
        .scalars()
        .all()
    )
    from app.models.settlement import adjustment_label  # noqa: F401

    return [
        {
            "id": r.id,
            "order_no": r.order_no,
            "settlement_month": r.settlement_month,
            "personnel_name": r.personnel_name,
            "direction": r.direction,
            "amount": str(r.amount),
            "reason": r.reason,
            "status": r.status,
        }
        for r in rows
    ]