pkgs/dart_mcp_server/lib/src/arg_parser.dart

// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:args/args.dart';

/// Creates an arg parser for th MCP server.
///
/// The `--help` option is only included if [includeHelp] is `true`.
///
/// Passing no options results in the default arg parser.
ArgParser createArgParser({
  bool includeHelp = true,
  bool allowTrailingOptions = false,
  int? usageLineLength,
}) {
  final parser =
      ArgParser(
          allowTrailingOptions: allowTrailingOptions,
          usageLineLength: usageLineLength,
        )
        ..addOption(
          dartSdkOption,
          help:
              'The path to the root of the desired Dart SDK. Defaults to the '
              'DART_SDK environment variable.',
        )
        ..addOption(
          flutterSdkOption,
          help:
              'The path to the root of the desired Flutter SDK. Defaults to '
              'the FLUTTER_SDK environment variable, then searching up from '
              'the Dart SDK.',
        )
        ..addFlag(
          forceRootsFallbackFlag,
          negatable: true,
          defaultsTo: false,
          help:
              'Forces a behavior for project roots which uses MCP tools '
              'instead of the native MCP roots. This can be helpful for '
              'clients like Cursor which claim to have roots support but do '
              'not actually support it.',
        )
        ..addOption(
          logFileOption,
          help:
              'Path to a file to log all MPC protocol traffic to. File will be '
              'overwritten if it exists.',
        )
        ..addMultiOption(
          excludeToolOption,
          help: 'The names of tools to exclude from this run of the server.',
        )
        ..addOption(
          toolsOption,
          help: 'The set of tools to enable.',
          allowed: ['all', 'dart'],
          allowedHelp: {
            'all': 'Enables all Dart and Flutter tools',
            'dart': 'Enables only tools relevant to pure Dart projects',
          },
          defaultsTo: 'all',
        );

  if (includeHelp) parser.addFlag(helpFlag, abbr: 'h', help: 'Show usage text');
  return parser;
}

const dartSdkOption = 'dart-sdk';
const excludeToolOption = 'exclude-tool';
const flutterSdkOption = 'flutter-sdk';
const forceRootsFallbackFlag = 'force-roots-fallback';
const helpFlag = 'help';
const logFileOption = 'log-file';
const toolsOption = 'tools';

enum ToolsConfiguration {
  all,
  dart;

  static ToolsConfiguration? fromArgs(ArgResults args) {
    final option = args.option(toolsOption);
    for (var value in ToolsConfiguration.values) {
      if (value.name == option) return value;
    }
    return null;
  }
}