PayrollManagementSystem/backend/app/services/settlement_service.py

"""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 datetime import date
from decimal import ROUND_HALF_UP, Decimal

from sqlalchemy import select
from sqlalchemy.exc import IntegrityError
from sqlalchemy.orm import Session

from app.core.constants import (
    MODULE_SETTLEMENT,
)
from app.core.db_errors import is_duplicate_entry
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,
    CALC_TYPE_RECEIPT,
)
from app.models.settlement import (
    SETTLEMENT_STATUS_APPROVED,
    SETTLEMENT_STATUS_DRAFT,
    SETTLEMENT_STATUS_PENDING,
    SETTLEMENT_STATUS_REJECTED,
)
from app.repositories import performance_ledger_repository, settlement_repository
from app.schemas.settlement import (
    SettlementDetailOut,
    SettlementOut,
    SettlementQuery,
)
from app.services import approval_service, audit_service, manager_share
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」（_release_previous_round 解绑回填后清明细重算）
    - 经理聚合（calc_type=2）在生成时计算并落库（#12 参数化见
      ``_build_manager_aggregates``）

    本函数只做编排，各段独立私有函数（口径修改只动对应段）。
    """
    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)
        _guard_regeneration(existing, month)
        _release_previous_round(session, existing, month)

        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）")

        aggregate_rows = _build_manager_aggregates(session, ledger_rows, month)
        settlement = _upsert_draft(session, existing, operator, month)
        items, ledger_ids = _build_items(session, ledger_rows, aggregate_rows, month)

        settlement_repository.replace_items(session, settlement.id, items)
        _apply_totals(settlement, items)
        settlement.snapshot_json = {"note": _SETTLEMENT_NOTE}
        # 入结回填：台账行 settlement_id 是「未入结」防重判据（_confirm_scope），
        # 不回填会让重生成把已固化行反复纳入；聚合行此刻已落库、id 可用
        settlement_repository.update_ledger_settlement_id(session, ledger_ids, settlement.id)

        # 出参在 commit 前固化（audit 约定：commit 后查询失败会把已生成的月结
        # 记成失败审计，与库中事实相反）
        session.flush()
        detail = _detail_of(session, settlement)
        session.commit()
        logger.info("月结生成 | month=%s | items=%s", month, len(items))
        return detail


def _guard_regeneration(existing: MonthlySettlement | None, month: str) -> None:
    """重生成准入：已审定 / 待审批不可重生成（草稿、已驳回放行）。"""
    if existing is None:
        return
    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")


def _release_previous_round(
    session: Session, existing: MonthlySettlement | None, month: str
) -> None:
    """释放上一轮固化标记（必须早于 _confirm_scope）。

    台账行 settlement_id 回填后，「未入结」过滤会把它们永久排除在候选集外；
    旧聚合行也要作废，否则本轮重建的聚合行与旧行重复计入。
    """
    if existing is None:
        return
    settlement_repository.clear_ledger_settlement_id(session, existing.id)
    performance_ledger_repository.deactivate_month_aggregates(session, month)


def _upsert_draft(
    session: Session, existing: MonthlySettlement | None, operator: User, month: str
) -> MonthlySettlement:
    """新建或重置草稿头表（重生成时刷新提交人与状态）。"""
    if existing is None:
        settlement = MonthlySettlement(
            settlement_month=month,
            submitter_id=operator.id,
            submitter_name=operator.username,
            status=SETTLEMENT_STATUS_DRAFT,
        )
        return settlement_repository.add(session, settlement)
    existing.submitter_id = operator.id
    existing.submitter_name = operator.username
    existing.status = SETTLEMENT_STATUS_DRAFT
    return existing


def _build_items(
    session: Session, ledger_rows: list, aggregate_rows: list, month: str
) -> tuple[list[SettlementItem], list[int]]:
    """按人汇总生成明细行，返回 (明细, 本次入结的台账行 id 列表)。"""
    by_person = _bucket_rows(ledger_rows + aggregate_rows)
    items = [_item_of(session, bucket, month) for _, bucket in sorted(by_person.items())]
    ledger_ids = [lid for bucket in by_person.values() for lid in bucket["ledger_ids"]]
    return items, ledger_ids


def _bucket_rows(rows: list) -> dict[tuple[int, int], dict]:
    """台账行按 (人员, 核算类型) 维度分桶（冗余人读字段取首行）。"""
    by_person: dict[tuple[int, int], dict] = {}
    for row in 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)
    return by_person


def _item_of(session: Session, bucket: dict, month: str) -> SettlementItem:
    """单条结算明细：月工资三口径净额、试用期说明与台账行引用列表。"""
    person = session.get(Personnel, bucket["personnel_id"])
    basic = person.salary_standard if person else None
    mode = _salary_mode_of(session, bucket["role_code"], month)
    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, month)} 元部分"
            "年底一次性结算"
        )
    return 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"]},
    )


def _apply_totals(settlement: MonthlySettlement, items: list[SettlementItem]) -> None:
    """头表三合计固化（明细已两位小数，合计再 HALF_UP 收口）。"""
    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})


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, for_update=True)
        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")

        try:
            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,
                # 月结明细在生成时已固化；提交时快照让复核者看到的是送审版本，
                # 而不是审批期间若发生重生成后的内容
                snapshot=approval_service.settlement_content(session, settlement.id),
            )
        except IntegrityError as exc:
            # version_no 唯一键的并发冲突（提交前已锁月结行，此项理论不可达，
            # 留作 DB 兜底）：审计上下文会统一回滚，这里只把 1062 翻译成
            # 可重试的业务提示，其余完整性错误原样上抛
            if is_duplicate_entry(exc):
                raise BadRequestError("提交冲突（版本号生成重复），请重试") from exc
            raise
        settlement.approval_order_no = order.order_no
        if order.status == SETTLEMENT_STATUS_APPROVED:
            mark_locked(session, settlement, operator=operator)
            logger.info("月结自动通过并锁定 | %s", settlement.settlement_month)
        else:
            settlement.status = SETTLEMENT_STATUS_PENDING

        # 出参在 commit 前固化（audit 约定：commit 后查询失败会把已提交的
        # 月结记成失败审计，与库中事实相反）
        session.flush()
        detail = _detail_of(session, settlement)
        session.commit()
        return detail


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**单笔回款**的有效台账行（未入结）。

    calc_type 必须限定单笔（1）：聚合行（2）也落同月台账、也会被回填
    settlement_id，不排除会在重生成时与新聚合行重复计入。
    """
    from app.models import PerformanceLedger

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


def _manager_share_params(session: Session, month: str) -> manager_share.ManagerShareParams:
    """薄委托 manager_share 共享模块：月结聚合与报表部门汇总同源取参。

    迁移说明（2026-10-19）：实现原样迁至 manager_share，行为零变化；
    参数按百分数存储（12.5 表示 12.5%），调用方不得再乘 100。
    """
    return manager_share.manager_share_params(session, month)


def _collect_team_buckets(
    session: Session, ledger_rows: list, include_manager_personal: bool
) -> dict[int, dict]:
    """薄委托 manager_share 共享模块：按经理采集团队业绩（行为零变化）。"""
    return manager_share.collect_team_buckets(session, ledger_rows, include_manager_personal)


def _aggregate_row(
    session: Session,
    manager,
    bucket: dict,
    company_base: Decimal,
    share: manager_share.ManagerShareParams,
):
    """单经理聚合台账行（必须落库：月结 ledger_ids 与报表下钻的锚点）。"""
    from app.models import PerformanceLedger

    amount = manager_team_share(
        bucket["performance"],
        company_base,
        team_pct=share.team_pct,
        company_pct=share.company_pct,
    )
    member_names = "、".join(sorted(bucket["names"])) or "（无成员）"
    return performance_ledger_repository.add(
        session,
        PerformanceLedger(
            receipt_id=None,
            calc_version=1,  # 聚合行无回款维度，版本恒 1（uk 含 NULL 不去重）
            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=share.param_date,
            # 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:{share.team_text}%+{share.company_text}%",
            converted_profit=None,
            performance_amount=amount.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP),
            barter_applied=0,
            payable_amount=amount.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP),
            settlement_month=share.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,
                "params_as_of": str(share.param_date),
                "manager_personal_included": 1 if share.include_manager_personal else 0,
                # 说明写给业务人员看：说清这一笔的基数是怎么凑出来的
                "note": (
                    f"团队分成：基数{'含' if share.include_manager_personal else '不含'}"
                    "经理本人名下业绩，按本团队与全公司两级比例合计计提"
                ),
            },
        ),
    )


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）并落库。

    #12 答复（2026-10-19）参数化：经理个人户业绩是否计入聚合基数由参数
    ``manager.personal.included`` 决定（0=不计入默认，1=计入）；
    经理 = 台账行归属人员经 manager_id 关联的 sales_manager 岗人员。
    """
    from app.repositories import business_role_repository

    share = _manager_share_params(session, month)
    managers = _collect_team_buckets(session, ledger_rows, share.include_manager_personal)
    # 全公司基数：默认排除经理个人户行（#12 开关计入时不过滤）；共享口径单点
    company_base = manager_share.company_base_of(ledger_rows, share.include_manager_personal)
    aggregates: list = []
    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
        aggregates.append(_aggregate_row(session, manager, bucket, company_base, share))
    return aggregates


def _month_end(month: str) -> date:
    """薄委托 manager_share 共享模块：YYYY-MM → 所属月月末（取参锚点）。

    保留包装：tests/unit/test_settlement_helpers.py 直接 import 本名字；
    「补生成历史月份结果不随操作日漂移」的原因说明见 manager_share.month_end。
    """
    return manager_share.month_end(month)


def _salary_mode_of(session: Session, role_code: str, month: str) -> str | None:
    from app.services.param_service import resolve_snapshot

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


def _probation_threshold(session: Session, month: str) -> Decimal:
    from app.services.param_service import parse_fraction, resolve_snapshot

    snapshot = resolve_snapshot(session, _month_end(month))
    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.services.no_generator import next_no

    amount = _adjustment_amount(payload)

    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=amount,
            reason=payload.reason.strip(),
            submitter_id=operator.id,
            submitter_name=operator.username,
        )
        session.add(order)
        session.flush()

        _wire_adjustment_approval(session, order, operator)
        out = _adjustment_out(order)  # 出参在 commit 前固化（audit 约定）
        session.commit()
        logger.info("调整单创建 | order=%s | status=%s", out["order_no"], out["status"])
        return out


def _adjustment_amount(payload) -> Decimal:
    """金额恒正校验（方向表达补发/扣减）。

    列注释即「恒正」约定，负数会让方向语义反转、审批/报表按 direction
    汇总出错；格式已由 schema 正则拦截，此处兜底转换 + 语义判定。
    """
    from decimal import InvalidOperation

    try:
        amount = Decimal(payload.amount)
    except InvalidOperation as exc:
        raise BadRequestError("调整金额格式非法（非负两位小数）") from exc
    if amount <= 0:
        raise BadRequestError("调整金额须大于 0（方向表达补发/扣减）")
    return amount


def _wire_adjustment_approval(session: Session, order, operator: User) -> None:
    """开关分流与留痕统一交给 submit_order（关=自动通过留痕；开=待财务复核）。

    **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）。
    """
    from app.models.approval import APPROVAL_STATUS_APPROVED, APPROVAL_TYPE_ADJUSTMENT
    from app.models.settlement import (
        ADJUSTMENT_STATUS_EFFECTIVE,
        ADJUSTMENT_STATUS_PENDING,
    )

    approval_order = approval_service.submit_order(
        session,
        order_type=APPROVAL_TYPE_ADJUSTMENT,
        ref_id=order.id,
        refer_no=order.order_no,
        submitter=operator,
        snapshot=approval_service.adjustment_content(session, order.id),
    )
    order.status = (
        ADJUSTMENT_STATUS_EFFECTIVE
        if approval_order.status == APPROVAL_STATUS_APPROVED
        else ADJUSTMENT_STATUS_PENDING
    )
    session.flush()


def _adjustment_out(order) -> dict:
    """调整单出参（commit 前固化；expire_on_commit 关闭下也不依赖后置读取）。"""
    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
    ]