"""统一编号序列（bre_sequence）—— 仅被 NumberGenService 直接写入，无业务 CRUD 端点。"""
from sqlalchemy import BigInteger, String
from sqlalchemy.orm import Mapped, mapped_column

from app.core.base_model import ModelMixin, MappedBase


class SequenceModel(ModelMixin, MappedBase):
    """原子取号计数器：name 唯一，current_seq 记录最近一次已发序号。"""

    __tablename__ = "bre_sequence"
    __table_args__ = ()  # 计数器表无 status 列，禁用 ModelMixin 默认的 status 索引

    name: Mapped[str] = mapped_column(String(128), unique=True, nullable=False, comment="序列名")
    current_seq: Mapped[int] = mapped_column(BigInteger, nullable=False, default=0, comment="最近已发序号")