"""
完成事件节点模块（新架构版本）
负责发送完成事件
"""

from typing import Any, Dict
from datetime import datetime

# 本地模块
from .state import AgentState
from backend.app.logger import info, warning

from langchain_core.runnables.config import RunnableConfig


async def finalize_node(state: AgentState, config: RunnableConfig) -> Dict[str, Any]:
    """
    完成事件节点（新架构版本）
    
    Args:
        state: 当前对话状态
        config: 运行时配置
    
    Returns:
        空（不修改状态）
    """
    info("[Finalize] 进入完成节点")
    
    try:
        # 获取流式写入器并发送完成事件
        from backend.app.main_graph.config import get_stream_writer
        writer = get_stream_writer()
        
        # 提取最后的回复
        final_reply = ""
        if state.messages:
            last_msg = state.messages[-1]
            final_reply = last_msg.content if hasattr(last_msg, 'content') else str(last_msg)
        
        # 只在 writer 存在且不是 noop 时才发送
        if writer and hasattr(writer, '__call__'):
            try:
                writer({
                    "type": "custom",
                    "data": {
                        "type": "done",
                        "token_usage": state.last_token_usage,
                        "elapsed_time": state.last_elapsed_time,
                        "final_result": final_reply
                    }
                })
                info("🏁 [完成事件] 已发送完成事件")
            except Exception as e:
                warning(f"⚠️ [完成事件] 发送完成事件失败 (非致命): {e}")
    except Exception as e:
        warning(f"⚠️ [完成事件] 处理失败 (非致命): {e}")
    
    info("[Finalize] 离开完成节点")
    return {}