from sqlalchemy.ext.asyncio import AsyncSession

from exceptions.exception import PermissionException
from module_admin.entity.vo.user_vo import CurrentUserModel
from module_business.dao.test_batch_dao import TestBatchDao
from module_business.domain.enums import TestBatchStatus
from module_business.domain.test_batch_scope import TestBatchScope
from module_business.entity.do.test_batch_do import BizTestBatch


class TestBatchAccessService:
    """测试批次作用域与管理权限校验。"""

    @staticmethod
    def _is_super_admin(current_user: CurrentUserModel) -> bool:
        return current_user.user is not None and current_user.user.admin is True

    @staticmethod
    def _raise_unavailable() -> None:
        raise PermissionException({'reason': 'TEST_BATCH_UNAVAILABLE'}, '当前测试批次不可用')

    @staticmethod
    def _raise_closed() -> None:
        raise PermissionException({'reason': 'TEST_BATCH_UNAVAILABLE'}, '当前测试批次已关闭')

    @classmethod
    def assert_super_admin(cls, current_user: CurrentUserModel) -> None:
        """确保当前用户由超级管理员标记明确授信。"""
        if not cls._is_super_admin(current_user):
            raise PermissionException('', '仅超级管理员可执行测试批次管理操作')

    @classmethod
    async def resolve_scope(
        cls,
        db: AsyncSession,
        current_user: CurrentUserModel,
        batch_id: int | None,
        *,
        write: bool = False,
    ) -> TestBatchScope:
        """解析并验证业务请求可使用的数据作用域。"""
        if batch_id is None:
            return TestBatchScope.formal()

        batch = await TestBatchDao.get_batch(db, batch_id)
        if batch is None or batch.status == TestBatchStatus.PURGED.value:
            cls._raise_unavailable()

        if not cls._is_super_admin(current_user):
            user_id = current_user.user.user_id if current_user.user is not None else None
            if user_id is None or not await TestBatchDao.user_is_authorized(db, batch_id, user_id):
                cls._raise_unavailable()

        if batch.status == TestBatchStatus.CLOSED.value:
            if write:
                cls._raise_closed()
            cls._raise_unavailable()
        if batch.status != TestBatchStatus.ACTIVE.value:
            cls._raise_unavailable()

        return TestBatchScope(
            batch_id=batch_id,
            mode='TEST',
            status=TestBatchStatus.ACTIVE,
            writable=True,
        )

    @classmethod
    async def lock_active_batch(cls, db: AsyncSession, scope: TestBatchScope) -> BizTestBatch | None:
        """在写入前锁定并重新确认测试批次仍为 ACTIVE。"""
        if scope.mode == 'FORMAL':
            return None

        batch = await TestBatchDao.get_batch_for_update(db, scope.batch_id)
        if batch is None or batch.status == TestBatchStatus.PURGED.value:
            cls._raise_unavailable()
        if batch.status == TestBatchStatus.CLOSED.value:
            cls._raise_closed()
        if batch.status != TestBatchStatus.ACTIVE.value:
            cls._raise_unavailable()
        return batch