"""表 2 加购行：领取、成功盖章、失败改状态。成功不插新行。"""
from __future__ import annotations

from collections.abc import Callable
from dataclasses import dataclass
from typing import Any

from db import RepoUnavailable, connect_from_env, oracle_dsn

OPERATE_TYPE_ADD_CART = 1
STATUS_OK = 1
STATUS_FAIL = 2
PUSH_NOT_SENT = 0
STAMP_SELECTION = "系统管理员"
STAMP_CLAIMING = "加购中"
STAMP_DONE = "加购班"
FAIL_REASON_MAX = 500

_CLAIM_SQL = """
UPDATE rpa_cart_settlement_goods_data
SET update_user_name = :stamp,
    update_time = SYSDATE
WHERE fid = :fid
  AND operate_type = 1
  AND status = 1
  AND push_status = 0
  AND NVL(update_user_name, :selection_stamp) = :selection_stamp
"""

_SUCCESS_SQL = """
UPDATE rpa_cart_settlement_goods_data
SET update_user_name = :stamp,
    fail_reason = NULL,
    update_time = SYSDATE
WHERE fid = :fid
  AND update_user_name = :claim_stamp
"""

_FAIL_SQL = """
UPDATE rpa_cart_settlement_goods_data
SET status = :status,
    fail_reason = :fail_reason,
    update_user_name = :stamp,
    update_time = SYSDATE
WHERE fid = :fid
  AND update_user_name = :claim_stamp
"""


@dataclass
class CartRow:
    fid: int
    oms_id: int
    platform_type: int
    supplier_name: str
    bar_code: str
    purchase_qty: int
    status: int
    fail_reason: str | None
    push_status: int
    update_user_name: str
    operate_type: int = OPERATE_TYPE_ADD_CART


def clip_reason(text: str) -> str:
    text = (text or "").strip()
    if len(text) <= FAIL_REASON_MAX:
        return text
    return text[: FAIL_REASON_MAX - 1] + "…"


def _is_pending(row: dict[str, Any]) -> bool:
    stamp = row.get("update_user_name") or STAMP_SELECTION
    return (
        int(row.get("operate_type") or 0) == OPERATE_TYPE_ADD_CART
        and int(row.get("status") or 0) == STATUS_OK
        and int(row.get("push_status") or 0) == PUSH_NOT_SENT
        and stamp == STAMP_SELECTION
    )


def _row_from_dict(data: dict[str, Any]) -> CartRow:
    qty = data.get("purchase_qty")
    return CartRow(
        fid=int(data["fid"]),
        oms_id=int(data["oms_id"]),
        platform_type=int(data["platform_type"]),
        supplier_name=str(data.get("supplier_name") or ""),
        bar_code=str(data.get("bar_code") or ""),
        purchase_qty=int(qty) if qty is not None else 0,
        status=int(data.get("status") or 0),
        fail_reason=data.get("fail_reason"),
        push_status=int(data.get("push_status") or 0),
        update_user_name=str(data.get("update_user_name") or ""),
        operate_type=int(data.get("operate_type") or OPERATE_TYPE_ADD_CART),
    )


class MemoryCartRepo:
    def __init__(self, rows: list[dict[str, Any]]):
        self.rows: dict[int, dict[str, Any]] = {int(row["fid"]): dict(row) for row in rows}

    def claim_pending(
        self, limit: int | None = None, platform_types: list[int] | None = None
    ) -> list[CartRow]:
        pending = sorted(
            (row for row in self.rows.values() if _is_pending(row)),
            key=lambda row: (int(row["oms_id"]), int(row["fid"])),
        )
        if platform_types is not None:
            allowed = set(platform_types)
            pending = [row for row in pending if int(row["platform_type"]) in allowed]
        if limit is not None:
            pending = pending[:limit]
        claimed: list[CartRow] = []
        for row in pending:
            row["update_user_name"] = STAMP_CLAIMING
            claimed.append(_row_from_dict(row))
        return claimed

    def mark_success(self, fid: int) -> None:
        row = self.rows[fid]
        row["update_user_name"] = STAMP_DONE
        row["fail_reason"] = None

    def mark_fail(self, fid: int, reason: str) -> None:
        row = self.rows[fid]
        row["status"] = STATUS_FAIL
        row["fail_reason"] = clip_reason(reason)
        row["update_user_name"] = STAMP_DONE


class OracleCartRepo:
    def __init__(self, connect: Callable):
        self._connect = connect

    @classmethod
    def from_env(cls) -> "OracleCartRepo":
        oracle_dsn()
        return cls(connect=connect_from_env)

    def claim_pending(
        self, limit: int | None = None, platform_types: list[int] | None = None
    ) -> list[CartRow]:
        conn = self._connect()
        try:
            with conn.cursor() as cur:
                sql, params = _pending_sql(limit=limit, platform_types=platform_types)
                cur.execute(sql, params)
                fetched = [_row_from_cursor(cur, rec) for rec in cur.fetchall()]
                claimed: list[CartRow] = []
                for row in fetched:
                    cur.execute(
                        _CLAIM_SQL,
                        {
                            "fid": row.fid,
                            "stamp": STAMP_CLAIMING,
                            "selection_stamp": STAMP_SELECTION,
                        },
                    )
                    if cur.rowcount == 1:
                        row.update_user_name = STAMP_CLAIMING
                        claimed.append(row)
            conn.commit()
            return claimed
        except Exception as exc:
            try:
                conn.rollback()
            except Exception:
                pass
            raise RepoUnavailable(str(exc)) from exc
        finally:
            conn.close()

    def mark_success(self, fid: int) -> None:
        self._execute(
            _SUCCESS_SQL,
            {"fid": int(fid), "stamp": STAMP_DONE, "claim_stamp": STAMP_CLAIMING},
        )

    def mark_fail(self, fid: int, reason: str) -> None:
        self._execute(
            _FAIL_SQL,
            {
                "fid": int(fid),
                "status": STATUS_FAIL,
                "fail_reason": clip_reason(reason),
                "stamp": STAMP_DONE,
                "claim_stamp": STAMP_CLAIMING,
            },
        )

    def _execute(self, sql: str, params: dict[str, Any]) -> None:
        conn = self._connect()
        try:
            with conn.cursor() as cur:
                cur.execute(sql, params)
            conn.commit()
        except Exception as exc:
            try:
                conn.rollback()
            except Exception:
                pass
            raise RepoUnavailable(str(exc)) from exc
        finally:
            conn.close()


def _row_from_cursor(cur, rec) -> CartRow:
    cols = [item[0].lower() for item in cur.description]
    return _row_from_dict(dict(zip(cols, rec)))


def _pending_sql(
    *, limit: int | None, platform_types: list[int] | None
) -> tuple[str, dict[str, Any]]:
    params: dict[str, Any] = {"selection_stamp": STAMP_SELECTION}
    filters = [
        "operate_type = 1",
        "status = 1",
        "push_status = 0",
        "NVL(update_user_name, :selection_stamp) = :selection_stamp",
    ]
    if platform_types is not None:
        if not platform_types:
            filters.append("1 = 0")
        else:
            keys: list[str] = []
            for index, platform in enumerate(platform_types):
                key = f"p{index}"
                keys.append(f":{key}")
                params[key] = int(platform)
            filters.append(f"platform_type IN ({', '.join(keys)})")
    sql = f"""
SELECT fid, oms_id, platform_type, supplier_name, bar_code,
       purchase_qty, status, fail_reason, push_status, update_user_name,
       operate_type
FROM rpa_cart_settlement_goods_data
WHERE {' AND '.join(filters)}
ORDER BY oms_id, fid
"""
    if limit is not None:
        params["limit"] = int(limit)
        sql = f"SELECT * FROM (\n{sql}\n) WHERE ROWNUM <= :limit"
    return sql, params