"""
对话相关的Pydantic模型
"""
from datetime import datetime
from typing import Optional, Dict, Any
from pydantic import BaseModel, Field


class ChatMessage(BaseModel):
    """聊天消息"""
    role: str = Field(..., description="角色：user或assistant")
    content: str = Field(..., description="消息内容")
    metadata: Optional[Dict[str, Any]] = Field(None, description="元数据")


class ChatRequest(BaseModel):
    """聊天请求"""
    message: str = Field(..., description="用户消息", min_length=1)
    session_id: Optional[str] = Field(None, description="会话ID")
    user_id: Optional[str] = Field(None, description="用户ID")


class ChatResponse(BaseModel):
    """聊天响应"""
    message: str = Field(..., description="助手回复")
    session_id: str = Field(..., description="会话ID")
    metadata: Optional[Dict[str, Any]] = Field(None, description="元数据")


class ConversationHistory(BaseModel):
    """对话历史"""
    session_id: str
    messages: list[ChatMessage]
    created_at: datetime

    class Config:
        from_attributes = True