from sqlalchemy import desc, delete, func, select, update
from sqlalchemy.ext.asyncio import AsyncSession
from module_admin.entity.do.approval_do import FlowApproval
from module_admin.entity.vo.approval_vo import ApprovalQueryObject
from module_admin.entity.vo.user_vo import CurrentUserModel
from sqlalchemy import select, text, cast, Integer, and_, or_, outerjoin, func, join
from utils.page_util import PageUtil


class ApprovalDao:
    """
    菜单管理模块数据库操作层
    """

    @classmethod
    async def add_flow_approval(cls, db: AsyncSession, flow_approval: FlowApproval):
        db.add(flow_approval)
        await db.flush()
        return flow_approval

    @classmethod
    async def get_flow_by_id(cls, db: AsyncSession, flowId: str):
        result = (
            (
                await db.execute(
                    select(FlowApproval).where(
                        FlowApproval.id == flowId
                    )
                )
            )
            .scalars()
            .first()
        )
        return result

    @classmethod
    async def edit_flow_approval(cls, db: AsyncSession, flow: dict):
        await db.execute(update(FlowApproval), [flow])

    @classmethod
    async def get_flow_list(cls, db: AsyncSession, query_param: ApprovalQueryObject, current_user: CurrentUserModel):
        query = (
            select(FlowApproval)
            .where(
                (FlowApproval.applicant == query_param.status) if query_param.applicant else True,
                (FlowApproval.businessType == query_param.businessType) if query_param.businessType else True,
                or_(
                    FlowApproval.approver == current_user.user.user_name,
                    FlowApproval.approver.in_(current_user.roles)
                ) if current_user.user.user_name != 'admin' else True
            )
            .order_by(FlowApproval.applyTime)
            .distinct()
        )
        # 注意：这里不执行查询，而是将查询对象传递给 paginate 方法
        result = await PageUtil.paginate(db, query, query_param.page_num, query_param.page_size, True)
        return result

    @classmethod
    async def get_waiting_total(cls, db: AsyncSession, current_user: CurrentUserModel):
        return (await db.execute(select(func.count()).select_from(FlowApproval)
                                 .where(FlowApproval.approver == current_user.user.user_name))).scalar()

    @classmethod
    async def get_flow_by_idAndUser(cls, db: AsyncSession, flow_id: str, username: str):
        result = (
            (
                await db.execute(
                    select(FlowApproval).where(
                        FlowApproval.id == flow_id,
                        FlowApproval.applicant == username
                    )
                )
            )
            .scalars()
            .first()
        )
        return result