"""方案分类模型。"""

from __future__ import annotations

from sqlalchemy import (
    BigInteger,
    Boolean,
    CheckConstraint,
    Computed,
    ForeignKey,
    Index,
    Integer,
    String,
    UniqueConstraint,
    text,
)
from sqlalchemy.orm import Mapped, mapped_column

from dms.database.base import BusinessTableMixin
from dms.extensions import db


class Category(BusinessTableMixin, db.Model):
    __tablename__ = "doc_category"
    __table_args__ = (
        UniqueConstraint(
            "category_code",
            "active_marker",
            name="uq_doc_category_category_code_active",
        ),
        CheckConstraint(
            "category_type IN ('SCENE', 'STYLE', 'SITUATION', 'VERSION', 'OTHER')",
            name="category_type",
        ),
        CheckConstraint(
            "status IN ('ENABLED', 'DISABLED')",
            name="category_status",
        ),
        Index(
            "ix_doc_category_parent_active_sort",
            "parent_id",
            "is_deleted",
            "sort_no",
        ),
        Index(
            "ix_doc_category_status_active",
            "status",
            "is_deleted",
        ),
        Index(
            "ix_doc_category_type_active",
            "category_type",
            "is_deleted",
        ),
    )

    parent_id: Mapped[int | None] = mapped_column(
        BigInteger,
        ForeignKey("doc_category.id", ondelete="RESTRICT"),
        nullable=True,
    )
    category_code: Mapped[str] = mapped_column(
        String(64),
        nullable=False,
    )
    category_name: Mapped[str] = mapped_column(String(128), nullable=False)
    category_type: Mapped[str] = mapped_column(
        String(32),
        nullable=False,
        server_default=text("'OTHER'"),
    )
    category_path: Mapped[str] = mapped_column(String(1000), nullable=False)
    sort_no: Mapped[int] = mapped_column(
        Integer,
        nullable=False,
        server_default=text("0"),
    )
    document_count: Mapped[int] = mapped_column(
        Integer,
        nullable=False,
        server_default=text("0"),
    )
    status: Mapped[str] = mapped_column(
        String(20),
        nullable=False,
        server_default=text("'ENABLED'"),
    )
    # 扁平模式：仅一级分类（parent_id IS NULL）有意义。
    # true 表示挂在该分类（含子分类）下的主案在前端不展示
    # "挂载子方案"与"挂载配套资料"入口；后端挂载接口不强制拒绝（弱约束）。
    flat_mode: Mapped[bool] = mapped_column(
        Boolean,
        nullable=False,
        server_default=text("0"),
    )
    # 类型显示名称：仅一级分类（parent_id IS NULL）有意义。
    # 检索结果列表中，该分类（含子分类）下主体方案的类型徽标
    # 显示该名称；NULL 表示未设置，回退显示分类名称。
    type_display_name: Mapped[str | None] = mapped_column(
        String(128),
        nullable=True,
    )
    active_marker: Mapped[int | None] = mapped_column(
        Integer,
        Computed("IF(is_deleted = 0, 1, NULL)", persisted=False),
        nullable=True,
    )