import json
from datetime import datetime
from pathlib import Path
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 (主键为 id)"""
    id: int
    card_id: int
    image_type: str
    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

    @field_validator('image_path', mode='before')
    @classmethod
    def format_image_path(cls, v:str):
        """将绝对文件路径转换为 'Data/filename.jpg' 格式的相对URL路径"""
        if not isinstance(v, str) or not v:
            return v
        p = Path(v)
        relative_path = f"{p.parent.name}/{p.name}"

        return relative_path

    @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 (主键为 id)"""
    id: int
    card_name: Optional[str] = None
    created_at: datetime
    updated_at: datetime
    images: List[CardImageResponse] = []

    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 (主键为 id)"""
    id: int  # 原 image_id
    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):
        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 CardListDetailResponse(BaseModel):
    """为新的卡牌列表接口定义的响应模型 (主键为 id)"""
    id: int  # 原 card_id
    card_name: Optional[str] = None
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True