#  Copyright 2026 zhaoxi826
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
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"""MCP 辅助模块：根据全局状态机中的配置创建 pydantic-ai MCPServer 实例。"""

from typing import Dict, List, Any, Optional, Sequence

from kilostar.utils.logger import get_logger

logger = get_logger("mcp_helper")

# 延迟导入 pydantic_ai.mcp，避免在 MCP 包未安装时崩溃
try:
    from pydantic_ai.mcp import (
        MCPServerStdio,
        MCPServerSSE,
        MCPServerHTTP,
    )
    _MCP_AVAILABLE = True
except ImportError:
    _MCP_AVAILABLE = False
    logger.warning("MCP package not installed. MCP servers will not be available.")


def build_mcp_toolsets(configs: Dict[str, Dict[str, Any]]) -> List[Any]:
    """根据配置字典创建 MCPServer 实例列表。

    Args:
        configs: {server_id: {"name": ..., "transport": ..., ...}}

    Returns:
        MCPServer 实例列表（可直接传给 Agent 的 toolsets 参数）
    """
    if not _MCP_AVAILABLE:
        return []

    toolsets = []
    for server_id, cfg in configs.items():
        try:
            transport = cfg.get("transport", "stdio")
            tool_prefix = cfg.get("tool_prefix")
            name = cfg.get("name", server_id)

            if transport == "stdio":
                server = MCPServerStdio(
                    command=cfg.get("command", ""),
                    args=cfg.get("args", []),
                    env=cfg.get("env"),
                    tool_prefix=tool_prefix,
                    id=server_id,
                )
            elif transport == "sse":
                server = MCPServerSSE(
                    url=cfg.get("url", ""),
                    tool_prefix=tool_prefix,
                    id=server_id,
                )
            elif transport == "http":
                server = MCPServerHTTP(
                    url=cfg.get("url", ""),
                    tool_prefix=tool_prefix,
                    id=server_id,
                )
            else:
                logger.warning(f"Unsupported MCP transport: {transport} for server {name}")
                continue

            toolsets.append(server)
            logger.info(f"MCP server '{name}' ({transport}) registered as toolset")
        except Exception as e:
            logger.error(f"Failed to build MCP server '{server_id}': {e}")

    return toolsets


async def get_mcp_toolsets_from_gsm() -> List[Any]:
    """从 GlobalStateMachine 拉取 MCP 配置并构建 toolsets。"""
    if not _MCP_AVAILABLE:
        return []

    try:
        from kilostar.core.global_state_machine.gsm_snapshot import fetch_snapshot

        # 走快照：MCP 配置变更频率极低，本地缓存命中率近 100%
        snapshot = await fetch_snapshot()
        return build_mcp_toolsets(snapshot.mcp_servers)
    except Exception as e:
        logger.error(f"Failed to load MCP configs from GSM: {e}")
        return []


async def get_all_toolsets_for_scope(
    scope: str, toolset_ids: Optional[List[str]] = None
) -> List[Any]:
    """汇总某个 scope 下的全部 toolset：system + personal + mcp。

    Args:
        scope: 调用方所属 scope。
        toolset_ids: agent 配置的 toolset 列表；为 None 表示返回全部。

    返回顺序保持稳定：先本地 toolset（按 toolset_ids），再 MCP toolset。
    任意一类拉取失败仅记录日志，不影响其他类。
    """
    toolsets: List[Any] = []
    try:
        from kilostar.core.global_state_machine.gsm_snapshot import (
            build_toolsets_for_scope,
            fetch_snapshot,
        )

        snapshot = await fetch_snapshot()
        local = build_toolsets_for_scope(snapshot, scope, toolset_ids=toolset_ids)
        if local:
            toolsets.extend(local)
    except Exception as e:
        logger.error(f"Failed to load local toolsets from GSM ({scope}): {e}")

    toolsets.extend(await get_mcp_toolsets_from_gsm())
    return toolsets


async def get_retrieval_toolsets_for_scope(scope: str) -> List[Any]:
    """仅返回 retrieval 工具集（system_node 专用）。不含 generation 和 MCP 工具。"""
    toolsets: List[Any] = []
    try:
        gsm = ray_actor_hook("global_state_machine").global_state_machine
        retrieval = await gsm.get_retrieval_toolsets_for_scope.remote(scope)
        if retrieval:
            toolsets.extend(retrieval)
    except Exception as e:
        logger.error(f"Failed to load retrieval toolsets ({scope}): {e}")
    return toolsets


async def list_mcp_tools_for_configs(
    configs: Dict[str, Dict[str, Any]],
) -> List[Dict[str, Any]]:
    """对每个 MCP 服务器逐个尝试连接，列出它们暴露的工具名。

    实现层面会进入 ``async with server:`` 上下文，调用一次 ``get_tools()``，
    再把工具名（带 tool_prefix）抽出来。任何一个 server 失败都不影响其他 server，
    出错时该项 ``tools=[]`` 并附带 ``error`` 字段。
    """
    result: List[Dict[str, Any]] = []
    if not _MCP_AVAILABLE:
        return result

    servers = build_mcp_toolsets(configs)
    for server in servers:
        server_id = getattr(server, "id", None)
        cfg = configs.get(server_id, {}) if server_id else {}
        name = cfg.get("name", server_id or "unknown")
        transport = cfg.get("transport", "stdio")
        item: Dict[str, Any] = {
            "server_id": server_id,
            "name": name,
            "transport": transport,
            "tool_prefix": cfg.get("tool_prefix"),
            "tools": [],
        }
        try:
            async with server:
                tools = await server.get_tools()
            item["tools"] = [
                getattr(t, "name", None) or getattr(t, "tool_name", str(t))
                for t in tools
            ]
        except Exception as e:
            item["error"] = str(e)
            logger.warning(f"MCP server '{name}' list_tools failed: {e}")
        result.append(item)
    return result


async def list_mcp_tools_from_gsm() -> List[Dict[str, Any]]:
    """从 GlobalStateMachine 拉取配置后调用 :func:`list_mcp_tools_for_configs`。"""
    if not _MCP_AVAILABLE:
        return []

    try:
        from kilostar.core.global_state_machine.gsm_snapshot import fetch_snapshot

        snapshot = await fetch_snapshot()
        return await list_mcp_tools_for_configs(snapshot.mcp_servers)
    except Exception as e:
        logger.error(f"Failed to list MCP tools from GSM: {e}")
        return []