from abc import ABC, abstractmethod
from typing import Optional, Tuple

from sqlalchemy import select, func, and_, or_, update
from sqlalchemy.ext.asyncio import AsyncSession

from common.database.db_session_manager import DB_SESSION_MNG
from common.database.model.models import items
from common.enums import ErrorType
from common.logger import LOG
from common.utils.gtime import GTime


# 상품 CRUD. 모든 조회/변경은 company_id 로 스코프된다(멀티테넌트).
class IItemCRUD(ABC):
    @abstractmethod
    async def search(self, cdb: AsyncSession, company_id, search, category, skip, limit) -> Tuple[ErrorType, list, int]:
        pass

    @abstractmethod
    async def distinct_categories(self, cdb: AsyncSession, company_id) -> Tuple[ErrorType, list]:
        pass

    @abstractmethod
    async def code_exists(self, cdb: AsyncSession, company_id, code) -> Tuple[ErrorType, bool]:
        pass

    @abstractmethod
    async def existing_codes(self, cdb: AsyncSession, company_id, codes: list) -> Tuple[ErrorType, list]:
        pass

    @abstractmethod
    async def get_by_id(self, cdb: AsyncSession, item_id) -> Tuple[ErrorType, items]:
        pass

    @abstractmethod
    async def add_item(self, cdb: AsyncSession, item: items) -> ErrorType:
        pass

    @abstractmethod
    async def update_item(self, cdb: AsyncSession, item_id, data: dict) -> ErrorType:
        pass

    @abstractmethod
    async def soft_delete(self, cdb: AsyncSession, item_id) -> ErrorType:
        pass


class ItemCRUD(IItemCRUD):
    async def search(
        self, cdb: AsyncSession, company_id, search: Optional[str], category: Optional[str], skip: int, limit: int
    ) -> Tuple[ErrorType, list, int]:
        try:
            conditions = [items.deleted == False, items.company_id == company_id]  # noqa: E712
            if search:
                conditions.append(or_(items.name.ilike(f"%{search}%"), items.code.ilike(f"%{search}%")))
            if category:
                conditions.append(items.category == category)
            where = and_(*conditions)

            cnt_err, cnt_rows = await DB_SESSION_MNG.execute(cdb, select(func.count()).select_from(items).where(where))
            if cnt_err != ErrorType.SUCCESS:
                return cnt_err, [], 0
            total = int(cnt_rows[0] or 0) if cnt_rows else 0

            list_err, rows = await DB_SESSION_MNG.execute(
                cdb,
                select(items).where(where).order_by(items.created_at.desc()).offset(skip).limit(limit),
            )
            if list_err != ErrorType.SUCCESS:
                return list_err, [], 0
            return ErrorType.SUCCESS, list(rows), total
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED, [], 0

    # 회사의 모든 상품에서 카테고리를 "이름 단위"로 중복 제거해 (이름, 대표 타입) 목록을 돌려준다.
    async def distinct_categories(self, cdb: AsyncSession, company_id) -> Tuple[ErrorType, list]:
        try:
            query = (
                select(items.category, func.min(items.category_type))
                .where(
                    items.company_id == company_id,
                    items.deleted == False,  # noqa: E712
                    items.category.isnot(None),
                    items.category != "",
                )
                .group_by(items.category)
                .order_by(items.category)
            )
            err_type, rows = await DB_SESSION_MNG.execute(cdb, query)
            if err_type != ErrorType.SUCCESS:
                return err_type, []
            return ErrorType.SUCCESS, list(rows)
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED, []

    async def code_exists(self, cdb: AsyncSession, company_id, code) -> Tuple[ErrorType, bool]:
        try:
            query = select(func.count()).select_from(items).where(
                items.company_id == company_id,
                items.code == code,
                items.deleted == False,  # noqa: E712
            )
            err_type, rows = await DB_SESSION_MNG.execute(cdb, query)
            if err_type != ErrorType.SUCCESS:
                return err_type, False
            cnt = int(rows[0] or 0) if rows else 0
            return ErrorType.SUCCESS, cnt > 0
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED, False

    async def existing_codes(self, cdb: AsyncSession, company_id, codes: list) -> Tuple[ErrorType, list]:
        try:
            if not codes:
                return ErrorType.SUCCESS, []
            query = select(items.code).where(
                items.company_id == company_id,
                items.code.in_(codes),
                items.deleted == False,  # noqa: E712
            )
            err_type, rows = await DB_SESSION_MNG.execute(cdb, query)
            if err_type != ErrorType.SUCCESS:
                return err_type, []
            return ErrorType.SUCCESS, [c for c in rows if c is not None]
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED, []

    async def get_by_id(self, cdb: AsyncSession, item_id) -> Tuple[ErrorType, items]:
        try:
            query = select(items).where(items.item_id == item_id, items.deleted == False).limit(1)  # noqa: E712
            err_type, row_list = await DB_SESSION_MNG.execute(cdb, query)
            if err_type != ErrorType.SUCCESS:
                return err_type, None
            if len(row_list) != 1:
                return ErrorType.DB_INVALID_KEY, None
            return ErrorType.SUCCESS, row_list[0]
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED, None

    async def add_item(self, cdb: AsyncSession, item: items) -> ErrorType:
        try:
            return await DB_SESSION_MNG.insert(cdb, item)
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED

    async def update_item(self, cdb: AsyncSession, item_id, data: dict) -> ErrorType:
        try:
            if not data:
                return ErrorType.SUCCESS
            query = update(items).where(items.item_id == item_id).values(**data)
            return await DB_SESSION_MNG.add(cdb, query)
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED

    async def soft_delete(self, cdb: AsyncSession, item_id) -> ErrorType:
        try:
            query = update(items).where(items.item_id == item_id).values(deleted=True, updated_at=GTime.UTC())
            return await DB_SESSION_MNG.add(cdb, query)
        except Exception as ex:
            LOG.e_no_callstack(ex)
            return ErrorType.DB_RUN_FAILED