"""Core 模拟库只读访问（jinrong_core · 无 HTTP API）。"""

from __future__ import annotations

from datetime import date
from typing import Any, Literal

from sqlalchemy import create_engine, text
from sqlalchemy.engine import Engine

from app.config.settings import settings

MatchResult = Literal["allowed", "allowed_with_disclosure", "forbidden", "professional_exempt", "risk_expired"]


class CoreReadOnlyRepository:
    """仅 SELECT jinrong_core；禁止写操作。"""

    def __init__(self, engine: Engine | None = None) -> None:
        self._engine = engine or self._default_engine()

    @staticmethod
    def _default_engine() -> Engine:
        pwd = settings.mysql_password
        auth = f"{settings.mysql_user}:{pwd}" if pwd else settings.mysql_user
        url = (
            f"mysql+pymysql://{auth}@{settings.mysql_host}:{settings.mysql_port}"
            f"/{settings.mysql_core_database}?charset=utf8mb4"
        )
        return create_engine(url, pool_pre_ping=True)

    def get_customer_l0(self, customer_id: str) -> dict[str, Any] | None:
        """L0 客户主档 + 正式风评（对齐用户信息数据示例 / 适当性指南）。"""
        sql = text(
            """
            SELECT c.*,
                   r.risk_code, r.questionnaire_score, r.max_loss_tolerance_pct,
                   r.investment_goal, r.investment_horizon, r.investor_category,
                   r.professional_approved_at,
                   r.evaluated_at AS risk_evaluated_at, r.expires_at AS risk_expires_at,
                   (r.expires_at < CURDATE()) AS risk_is_expired
            FROM core_customer c
            LEFT JOIN core_customer_risk r ON r.customer_id = c.customer_id
            WHERE c.customer_id = :cid AND c.is_active = 1
            """
        )
        with self._engine.connect() as conn:
            row = conn.execute(sql, {"cid": customer_id}).mappings().first()
            return dict(row) if row else None

    def check_suitability(self, customer_id: str, product_id: str) -> dict[str, Any]:
        """R-02：基于 L0 C 等级 + 产品 R 等级 + 适当性矩阵判定。

        返回字段与 risk_suitability_log 一一对应，见 docs/项目框架设计/表设计/07-risk_suitability_log说明.md
        """
        sql = text(
            """
            SELECT c.customer_id, c.age, c.is_hnw,
                   r.risk_code AS customer_risk_code,
                   r.investor_category, r.expires_at AS risk_expires_at,
                   (r.expires_at < CURDATE()) AS risk_is_expired,
                   p.product_id, p.product_name, p.min_risk_code AS product_risk_code,
                   p.min_subscribe_amount, p.term_days, p.requires_disclosure AS product_requires_disclosure,
                   sr.match_result AS matrix_match_result
            FROM core_customer c
            JOIN core_customer_risk r ON r.customer_id = c.customer_id
            JOIN core_product p ON p.product_id = :pid
            LEFT JOIN core_suitability_rule sr
              ON sr.customer_risk_code = r.risk_code
             AND sr.product_risk_code = p.min_risk_code
            WHERE c.customer_id = :cid AND c.is_active = 1
            """
        )
        with self._engine.connect() as conn:
            row = conn.execute(sql, {"cid": customer_id, "pid": product_id}).mappings().first()
            if not row:
                return self._suitability_result(
                    customer_id=customer_id,
                    product_id=product_id,
                    match_result="forbidden",
                    mismatch_type="not_found",
                    matched=False,
                    blocked=True,
                    reason="客户或产品不存在",
                    block_response_code="SUIT_NOT_FOUND",
                )

            data = dict(row)
            base = {
                "customer_id": data["customer_id"],
                "product_id": data["product_id"],
                "product_name": data.get("product_name"),
                "customer_risk_code": data.get("customer_risk_code"),
                "product_risk_code": data.get("product_risk_code"),
                "investor_category": data.get("investor_category") or "ordinary",
                "age": data.get("age"),
                "is_hnw": data.get("is_hnw"),
                "risk_expires_at": data.get("risk_expires_at"),
                "risk_is_expired": bool(data.get("risk_is_expired")),
                "min_subscribe_amount": data.get("min_subscribe_amount"),
                "term_days": data.get("term_days"),
            }

            if base["risk_is_expired"]:
                return self._suitability_result(
                    **base,
                    match_result="risk_expired",
                    mismatch_type="risk_expired",
                    matched=False,
                    blocked=True,
                    reason="风评已过期（FM-03），须重新测评",
                    block_response_code="SUIT_RISK_EXPIRED",
                )

            if base["investor_category"] == "professional":
                return self._suitability_result(
                    **base,
                    match_result="professional_exempt",
                    mismatch_type="professional_exempt",
                    matched=True,
                    blocked=False,
                    requires_disclosure=False,
                    reason="专业投资者豁免适当性匹配",
                    block_response_code="SUIT_PROFESSIONAL_EXEMPT",
                )

            matrix = data.get("matrix_match_result")
            if matrix == "forbidden" or matrix is None:
                return self._suitability_result(
                    **base,
                    match_result="forbidden",
                    mismatch_type="risk_level",
                    matched=False,
                    blocked=True,
                    reason="客户风险等级与产品最低等级不匹配",
                    block_response_code="SUIT_RISK_MISMATCH",
                )

            requires_disclosure = matrix == "allowed_with_disclosure" or bool(
                data.get("product_requires_disclosure")
            )
            matched = True
            blocked = False
            match_result = "allowed_with_disclosure" if requires_disclosure else "allowed"
            block_response_code = "SUIT_NEED_DISCLOSURE" if requires_disclosure else "SUIT_OK"
            mismatch_type = "none"
            reason: str | None = None

            age = base.get("age") or 0
            prod_r = base.get("product_risk_code") or ""
            needs_branch_confirm = age >= 70 and prod_r >= "R3"
            if needs_branch_confirm:
                blocked = True
                mismatch_type = "age_branch_confirm"
                reason = "年龄70岁及以上购买R3及以上产品需网点当面确认（FM-01）"
                block_response_code = "SUIT_AGE_CONFIRM"

            return self._suitability_result(
                **base,
                match_result=match_result,
                mismatch_type=mismatch_type,
                matched=matched,
                blocked=blocked,
                requires_disclosure=requires_disclosure,
                needs_branch_confirm=needs_branch_confirm,
                reason=reason,
                block_response_code=block_response_code,
            )

    @staticmethod
    def _suitability_result(
        *,
        customer_id: str | None = None,
        product_id: str | None = None,
        product_name: str | None = None,
        customer_risk_code: str | None = None,
        product_risk_code: str | None = None,
        investor_category: str = "ordinary",
        age: int | None = None,
        is_hnw: bool | None = None,
        risk_expires_at: Any = None,
        risk_is_expired: bool = False,
        min_subscribe_amount: Any = None,
        term_days: Any = None,
        match_result: str,
        mismatch_type: str,
        matched: bool,
        blocked: bool,
        requires_disclosure: bool = False,
        needs_branch_confirm: bool = False,
        reason: str | None = None,
        block_response_code: str = "SUIT_OK",
    ) -> dict[str, Any]:
        return {
            "customer_id": customer_id,
            "product_id": product_id,
            "product_name": product_name,
            "customer_risk_code": customer_risk_code,
            "product_risk_code": product_risk_code,
            "investor_category": investor_category,
            "age": age,
            "is_hnw": is_hnw,
            "risk_expires_at": risk_expires_at,
            "risk_is_expired": risk_is_expired,
            "min_subscribe_amount": min_subscribe_amount,
            "term_days": term_days,
            "match_result": match_result,
            "mismatch_type": mismatch_type,
            "matched": matched,
            "blocked": blocked,
            "requires_disclosure": requires_disclosure,
            "needs_branch_confirm": needs_branch_confirm,
            "reason": reason,
            "block_response_code": block_response_code,
        }

    def list_products_for_customer(
        self, customer_id: str, limit: int = 50
    ) -> list[dict[str, Any]]:
        """C-11：列出开放产品及与客户 C 等级的匹配结果。"""
        sql = text(
            """
            SELECT p.*, sr.match_result,
                   (r.expires_at < CURDATE()) AS risk_is_expired,
                   r.risk_code AS customer_risk_code,
                   r.investor_category
            FROM core_product p
            CROSS JOIN core_customer_risk r
            LEFT JOIN core_suitability_rule sr
              ON sr.customer_risk_code = r.risk_code
             AND sr.product_risk_code = p.min_risk_code
            WHERE r.customer_id = :cid AND p.is_open = 1
            ORDER BY p.min_risk_code, p.product_id
            LIMIT :lim
            """
        )
        with self._engine.connect() as conn:
            rows = conn.execute(sql, {"cid": customer_id, "lim": limit}).mappings().all()
            return [dict(r) for r in rows]

    def list_holdings(self, customer_id: str) -> list[dict[str, Any]]:
        sql = text(
            """
            SELECT h.*, p.product_name, p.min_risk_code, p.product_type,
                   p.min_subscribe_amount, p.term_days
            FROM core_holding h
            JOIN core_product p ON p.product_id = h.product_id
            WHERE h.customer_id = :cid
            ORDER BY h.market_value DESC
            """
        )
        with self._engine.connect() as conn:
            return [dict(r) for r in conn.execute(sql, {"cid": customer_id}).mappings()]

    def list_trades(
        self, customer_id: str, since: date | None = None, limit: int = 50
    ) -> list[dict[str, Any]]:
        sql = text(
            """
            SELECT t.*, p.product_name, p.min_risk_code
            FROM core_trade t
            JOIN core_product p ON p.product_id = t.product_id
            WHERE t.customer_id = :cid
              AND (:since IS NULL OR t.traded_at >= :since)
            ORDER BY t.traded_at DESC
            LIMIT :lim
            """
        )
        with self._engine.connect() as conn:
            return [
                dict(r)
                for r in conn.execute(
                    sql, {"cid": customer_id, "since": since, "lim": limit}
                ).mappings()
            ]

    def get_product(self, product_id: str) -> dict[str, Any] | None:
        sql = text("SELECT * FROM core_product WHERE product_id = :pid")
        with self._engine.connect() as conn:
            row = conn.execute(sql, {"pid": product_id}).mappings().first()
            return dict(row) if row else None

    def get_latest_nav(self, product_id: str) -> dict[str, Any] | None:
        sql = text(
            """
            SELECT * FROM core_product_nav
            WHERE product_id = :pid
            ORDER BY nav_date DESC LIMIT 1
            """
        )
        with self._engine.connect() as conn:
            row = conn.execute(sql, {"pid": product_id}).mappings().first()
            return dict(row) if row else None

    def list_customers_by_advisor(self, advisor_id: str) -> list[str]:
        sql = text(
            """
            SELECT customer_id FROM core_customer_advisor
            WHERE advisor_id = :aid AND rel_status = 'active'
            """
        )
        with self._engine.connect() as conn:
            return [r[0] for r in conn.execute(sql, {"aid": advisor_id})]

    def get_staff(self, staff_id: str) -> dict[str, Any] | None:
        sql = text(
            "SELECT staff_id, display_name, staff_type, roles FROM core_staff WHERE staff_id = :sid AND is_active = 1"
        )
        with self._engine.connect() as conn:
            row = conn.execute(sql, {"sid": staff_id}).mappings().first()
            return dict(row) if row else None

    def is_advisor_assigned(self, advisor_id: str, customer_id: str) -> bool:
        sql = text(
            """
            SELECT 1 FROM core_customer_advisor
            WHERE advisor_id = :aid AND customer_id = :cid AND rel_status = 'active'
            LIMIT 1
            """
        )
        with self._engine.connect() as conn:
            return conn.execute(sql, {"aid": advisor_id, "cid": customer_id}).first() is not None