import json
from datetime import datetime
from typing import Optional, Dict, Any, List
from pydantic import BaseModel, field_validator


# --- Pydantic 数据模型 ---

class CardImageResponse(BaseModel):
    """用于API响应的图片数据模型"""
    image_id: int
    image_name: Optional[str] = None
    image_path: str
    detection_json: Dict[str, Any]
    modified_json: Optional[Dict[str, Any]] = None
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True  # 兼容 ORM 模式

    @field_validator('detection_json', 'modified_json', mode='before')
    @classmethod
    def parse_json_string(cls, v):
        if v is None:
            return None
        if isinstance(v, str):
            try:
                return json.loads(v)
            except json.JSONDecodeError:
                raise ValueError("Invalid JSON string in database")
        return v


class CardDetailResponse(BaseModel):
    """用于响应单个卡牌详细信息的模型，包含其所有图片信息"""
    card_id: int
    card_name: Optional[str] = None
    created_at: datetime
    updated_at: datetime
    images: List[CardImageResponse] = []  # 嵌套的图片列表

    class Config:
        from_attributes = True


class ImageJsonPairResponse(BaseModel):
    """用于获取单个图片两个JSON数据的响应模型"""
    image_id: int
    detection_json: Dict[str, Any]
    modified_json: Optional[Dict[str, Any]] = None

    class Config:
        from_attributes = True

    @field_validator('detection_json', 'modified_json', mode='before')
    @classmethod
    def parse_json_string(cls, v):
        """
        这个验证器会在Pydantic进行类型检查之前运行。
        它负责将从数据库取出的JSON字符串转换为Python字典。
        """
        if v is None:
            return None
        if isinstance(v, str):
            try:
                return json.loads(v)
            except json.JSONDecodeError:
                raise ValueError("Invalid JSON string in database")
        return v


# 用于 card list的结构
class CardImageInfo(BaseModel):
    """用于在卡牌列表中展示的单张图片摘要信息"""
    image_id: int
    image_name: Optional[str] = None


class CardListDetailResponse(BaseModel):
    """为新的卡牌列表接口定义的详细响应模型"""
    card_id: int
    card_name: Optional[str] = None
    created_at: datetime
    updated_at: datetime

    # 使用嵌套模型来表示每张图片的信息
    front_face: Optional[CardImageInfo] = None
    back_face: Optional[CardImageInfo] = None
    front_edge: Optional[CardImageInfo] = None
    back_edge: Optional[CardImageInfo] = None

    class Config:
        from_attributes = True