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

class VasSchemaBase(BaseModel):
    name: Optional[str] = None
    description: Optional[str] = None
    
    # 1. 将字段重命名为 schema_content (避免与 BaseModel.schema_json 冲突)
    # 2. 使用 alias="schema_json" 确保前端传参或数据库读取时 key 仍然是 "schema_json"
    schema_content: Optional[Dict[str, Any]] = Field(default=None, alias="schema_json")

    # 配置允许通过字段名或别名进行赋值
    model_config = ConfigDict(populate_by_name=True)

    # 3. 验证器指向新的字段名 schema_content
    @field_validator("schema_content", mode="before")
    def normalize_json_field(cls, v):
        if v is None:
            return None
        if isinstance(v, str):
            try:
                return json.loads(v)
            except Exception:
                return {}
        return v

class VasSchemaCreate(VasSchemaBase):
    name: str
    description: str
    # 这里也要重命名，并加上 alias
    schema_content: Dict[str, Any] = Field(..., alias="schema_json")

class VasSchemaUpdate(VasSchemaBase):
    pass

class VasSchemaOut(VasSchemaBase):
    id: int
    created_at: datetime
    updated_at: datetime

    # 继承 Base 的配置，并在其基础上增加 from_attributes
    model_config = ConfigDict(
        populate_by_name=True,
        from_attributes=True
    )