// server.ts
import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import {
  CallToolRequestSchema,
  ListToolsRequestSchema,
  ListResourcesRequestSchema,
  ReadResourceRequestSchema,
} from '@modelcontextprotocol/sdk/types.js';
import * as fs from 'fs/promises';
import * as path from 'path';
import { z } from 'zod';

// 定义工具参数模式
const ReadFileSchema = z.object({
  path: z.string().describe('文件路径'),
});

const WriteFileSchema = z.object({
  path: z.string().describe('文件路径'),
  content: z.string().describe('文件内容'),
});

// 创建 MCP 服务器
const server = new Server(
  {
    name: 'filesystem-server',
    version: '1.0.0',
  },
  {
    capabilities: {
      tools: {},
      resources: {},
    },
  }
);

// 列出可用工具
server.setRequestHandler(ListToolsRequestSchema, async () => {
  return {
    tools: [
      {
        name: 'read_file',
        description: '读取文件内容',
        inputSchema: {
          type: 'object',
          properties: {
            path: {
              type: 'string',
              description: '要读取的文件路径',
            },
          },
          required: ['path'],
        },
      },
      {
        name: 'write_file',
        description: '写入文件内容',
        inputSchema: {
          type: 'object',
          properties: {
            path: {
              type: 'string',
              description: '要写入的文件路径',
            },
            content: {
              type: 'string',
              description: '文件内容',
            },
          },
          required: ['path', 'content'],
        },
      },
    ],
  };
});

// 处理工具调用
server.setRequestHandler(CallToolRequestSchema, async (request) => {
  const { name, arguments: args } = request.params;

  try {
    if (name === 'read_file') {
      const { path: filePath } = ReadFileSchema.parse(args);
      const content = await fs.readFile(filePath, 'utf-8');
      return {
        content: [
          {
            type: 'text',
            text: content,
          },
        ],
      };
    }

    if (name === 'write_file') {
      const { path: filePath, content } = WriteFileSchema.parse(args);
      await fs.writeFile(filePath, content, 'utf-8');
      return {
        content: [
          {
            type: 'text',
            text: `文件已成功写入: ${filePath}`,
          },
        ],
      };
    }

    throw new Error(`未知工具: ${name}`);
  } catch (error) {
    return {
      content: [
        {
          type: 'text',
          text: `错误: ${error instanceof Error ? error.message : String(error)}`,
        },
      ],
      isError: true,
    };
  }
});

// 启动服务器
async function main() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error('MCP Filesystem Server running on stdio');
}

main().catch(console.error);