#!/usr/bin/env node

import { spawn } from "node:child_process";
import fs from "node:fs";
import path from "node:path";

function resolveWorkspaceDir() {
  const workspaceDir = process.env.COPILOT_MCP_FILESYSTEM_ROOT
    ? path.resolve(process.env.COPILOT_MCP_FILESYSTEM_ROOT)
    : process.cwd();

  if (!fs.existsSync(workspaceDir)) {
    throw new Error(`Filesystem MCP workspace does not exist: ${workspaceDir}`);
  }

  if (!fs.statSync(workspaceDir).isDirectory()) {
    throw new Error(`Filesystem MCP workspace is not a directory: ${workspaceDir}`);
  }

  return workspaceDir;
}

function main() {
  const workspaceDir = resolveWorkspaceDir();
  const dockerArgs = [
    "run",
    "-i",
    "--rm",
    "--mount",
    `type=bind,src=${workspaceDir},dst=/projects/workspace`,
    "mcp/filesystem",
    "/projects/workspace",
  ];

  const child = spawn("docker", dockerArgs, {
    stdio: "inherit",
    windowsHide: true,
  });

  child.on("error", (error) => {
    console.error(`Failed to start Docker for the filesystem MCP server: ${error.message}`);
    process.exit(1);
  });

  for (const signal of ["SIGINT", "SIGTERM", "SIGHUP"]) {
    process.on(signal, () => {
      if (!child.killed) {
        child.kill(signal);
      }
    });
  }

  child.on("exit", (code, signal) => {
    if (signal) {
      console.error(`Filesystem MCP server exited with signal ${signal}`);
      process.exit(1);
    }

    process.exit(code ?? 0);
  });
}

main();