from pydantic import BaseModel, ConfigDict, Field, field_validator


class VariableItemSchema(BaseModel):
    """单个变量-章节关联项。"""

    variable_name: str = Field(..., min_length=1, max_length=128, description="变量名称")
    chapter_names: list[str] = Field(default_factory=list, description="关联章节名称列表")
    checked: bool | None = Field(default=None, description="当前标注是否勾选该变量，单标注保存接口使用")

    @field_validator("variable_name")
    @classmethod
    def validate_required(cls, value: str) -> str:
        value = value.strip()
        if not value:
            raise ValueError("必填字段不能为空")
        return value

    @field_validator("chapter_names")
    @classmethod
    def validate_chapter_names(cls, values: list[str]) -> list[str]:
        result: list[str] = []
        for value in values:
            chapter_name = value.strip()
            if not chapter_name:
                raise ValueError("章节名称不能为空")
            result.append(chapter_name)
        return result


class VariableSaveSchema(BaseModel):
    """批量保存变量-章节关联。"""

    template_id: int = Field(..., ge=1, description="模板ID")
    variables: list[VariableItemSchema] = Field(default_factory=list, description="变量列表")


class VariableOutSchema(BaseModel):
    """变量-章节关联响应模型。"""

    model_config = ConfigDict(from_attributes=True)

    id: int = Field(description="主键ID")
    template_id: int = Field(description="模板ID")
    variable_name: str = Field(description="变量名称")
    chapter_name: str = Field(description="章节名称")


class VariableGroupOutSchema(BaseModel):
    """按变量分组的响应模型。"""

    variable_name: str = Field(description="变量名称")
    chapter_names: list[str] = Field(default_factory=list, description="关联章节名称列表")
    chapters: list[dict] = Field(default_factory=list, description="关联章节详情列表")