from datetime import datetime
from typing import Optional, List, Generic, T

from ninja import Schema
from pydantic import Field


# --- 假设的关联模型 Schema ---
class AuthorSchema(Schema):
    id: int
    username: str


class SectionSchema(Schema):
    id: int
    title: str  # 假设 MainMenu 有 name 字段


class AttachmentSchema(Schema):
    id: int
    file: str  # 返回文件 URL 路径，如 "articles/attachments/2026/04/03/file.pdf"


class PaginatedResponseSchema(Schema, Generic[T]):
    items: List[T]
    total: int
    page: int
    per_page: int
    total_pages: int


# --- Article 主 Schema ---
class ArticleSchema(Schema):
    id: int
    title: str
    content: str
    cover: Optional[str] = None  # 图片 URL 路径
    is_contribution: bool
    is_published: bool
    created_at: datetime
    updated_at: datetime

    # 关联字段
    author: Optional[AuthorSchema] = None
    section: Optional[SectionSchema] = None
    attachments: List[AttachmentSchema] = Field(default_factory=list)


# --- 创建文章用的 Schema (不含只读字段) ---
class ArticleCreateSchema(Schema):
    title: str
    section_id: Optional[int] = None  # 外键通过 ID 传递
    content: str
    cover: Optional[str] = None  # 注意：文件上传通常需单独处理，此处仅为文本路径示例
    is_contribution: bool = False
    is_published: bool = True


# --- 更新文章用的 Schema ---
class ArticleUpdateSchema(ArticleCreateSchema):
    title: Optional[str] = None
    content: Optional[str] = None