"""
Dev Agent MCP Server
将 Dev Agent 封装为 MCP 工具，供 CodeBuddy 等 MCP 客户端调用。

功能：
- run_dev_agent: 提交任务给 Dev Agent 执行，返回执行结果
  - 支持指定 session_id 进行多轮对话
  - 自动提取最终回复文本

环境变量配置：
- DEV_AGENT_API_URL: API Server 地址（默认 http://127.0.0.1:8001）
- DEV_AGENT_APP_NAME: 调用的 agent 名称（默认 my_agent）
- DEV_AGENT_USER_ID: 用户 ID（默认 codebuddy）
"""
import os
import sys

# 强制 UTF-8
os.environ["PYTHONUTF8"] = "1"

import httpx
from mcp.server.fastmcp import FastMCP


# 配置
DEV_AGENT_API_URL = os.getenv("DEV_AGENT_API_URL", "http://127.0.0.1:8001")
DEV_AGENT_APP_NAME = os.getenv("DEV_AGENT_APP_NAME", "my_agent")
DEV_AGENT_USER_ID = os.getenv("DEV_AGENT_USER_ID", "codebuddy")

# MCP Server
mcp = FastMCP(name=f"dev-agent-{DEV_AGENT_APP_NAME}")


@mcp.tool()
async def run_dev_agent(task: str, session_id: str = "default") -> str:
    """调用 Dev Agent（全栈开发子 Agent）执行开发任务。

    Dev Agent 可以读写文件、运行终端命令、执行编译/构建/测试。
    适用于：代码编写、bug 修复、项目搭建、编译验证等开发子任务。

    Args:
        task: 要 Dev Agent 执行的任务描述，越详细越好
        session_id: 可选，会话 ID，用于多轮对话/续聊，默认 "default"

    Returns:
        Dev Agent 的执行结果
    """
    if not task:
        return "错误：task 不能为空"

    # 构造请求
    payload = {
        "appName": DEV_AGENT_APP_NAME,
        "userId": DEV_AGENT_USER_ID,
        "sessionId": session_id,
        "newMessage": {
            "role": "user",
            "parts": [{"text": task}],
        },
    }

    try:
        async with httpx.AsyncClient(timeout=600.0) as client:  # 10 分钟超时
            response = await client.post(
                f"{DEV_AGENT_API_URL}/run",
                json=payload,
                headers={"Content-Type": "application/json"},
            )

            if response.status_code != 200:
                return (
                    f"调用 Dev Agent 失败（HTTP {response.status_code}）:\n"
                    f"{response.text[:500]}"
                )

            events = response.json()
    except httpx.ConnectError:
        return (
            f"无法连接到 Dev Agent API Server（{DEV_AGENT_API_URL}）\n"
            f"请确认 api_server.py 是否已启动。"
        )
    except Exception as e:
        return f"调用 Dev Agent 出错: {e}"

    # 从事件列表中提取最终回复
    return _extract_final_response(events, session_id)


def _extract_final_response(events: list[dict], session_id: str) -> str:
    """从事件列表中提取 agent 的最终文本回复"""
    if not events:
        return "（无返回事件）"

    final_text_parts = []

    for event in events:
        content = event.get("content", {})
        role = content.get("role", "")
        parts = content.get("parts", [])
        author = event.get("author", "")

        if role == "model" and author == DEV_AGENT_APP_NAME:
            for part in parts:
                if "text" in part:
                    final_text_parts.append(part["text"])

    response = "\n".join(final_text_parts).strip()

    if not response:
        # 如果没有找到最终回复，返回事件摘要
        summary = f"共 {len(events)} 个事件\n"
        for e in events[-5:]:
            content = e.get("content", {})
            parts = content.get("parts", [])
            role = content.get("role", "")
            author = e.get("author", "")
            part_types = [list(p.keys())[0] for p in parts]
            summary += f"  - [{role}] {author}: {part_types}\n"
        response = f"（未提取到最终文本回复）\n{summary}"

    # 附上 session_id 方便续聊
    response += f"\n\n---\nsession_id: {session_id}"
    return response


def main():
    """stdio 模式启动 MCP server"""
    # Windows stdio 二进制模式
    if sys.platform == "win32":
        import msvcrt
        msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
        msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)

    mcp.run(transport="stdio")


if __name__ == "__main__":
    main()