import 'dart:io';

import 'package:args/args.dart';
import 'package:koi_swagger_parser/koi_swagger_parser.dart';

Future<void> main(List<String> arguments) async {
  final parser = ArgParser()
    ..addFlag('help', abbr: 'h', negatable: false, help: '显示帮助信息。');

  final generateParser = ArgParser()
    ..addFlag('all', abbr: 'a', negatable: false, help: '兼容旧命令格式，当前等价于生成全部资源。')
    ..addOption('config', abbr: 'c', help: '配置文件路径。')
    ..addOption('cwd', help: '工作目录。')
    ..addFlag('dry-run', negatable: false, help: '只解析与渲染，不落盘。')
    ..addFlag('verbose', abbr: 'v', negatable: false, help: '打印更多诊断信息。');
  parser.addCommand('generate', generateParser);

  late final ArgResults result;
  try {
    result = parser.parse(arguments);
  } on FormatException catch (error) {
    stderr.writeln(error.message);
    stderr.writeln(parser.usage);
    exitCode = 64;
    return;
  }

  if ((result['help'] as bool?) ?? false) {
    stdout.writeln(_usage(parser));
    return;
  }

  final command = result.command;
  if (command == null || command.name == 'generate') {
    final commandArgs = command ?? result;
    await _runGenerate(commandArgs, parser);
    return;
  }

  stdout.writeln(_usage(parser));
}

Future<void> _runGenerate(ArgResults result, ArgParser parser) async {
  final generator = const KoiSwaggerParser();
  try {
    final summary = await generator.generate(
      configPath: result['config'] as String?,
      workingDirectory: result['cwd'] as String?,
      dryRun: result['dry-run'] as bool? ?? false,
      verbose: result['verbose'] as bool? ?? false,
    );

    final mode = summary.dryRun ? 'dry-run' : 'written';
    stdout.writeln(
      '[koi_swagger_parser] $mode ${summary.writtenFiles.length} file(s), '
      '${summary.operationsCount} operation(s), '
      '${summary.modelsCount} model(s).',
    );
  } on Object catch (error, stackTrace) {
    stderr.writeln('[koi_swagger_parser] generation failed: $error');
    if ((result['verbose'] as bool?) ?? false) {
      stderr.writeln(stackTrace);
    } else {
      stderr.writeln('使用 --verbose 可以查看详细堆栈。');
    }
    stderr.writeln(parser.usage);
    exitCode = 1;
  }
}

String _usage(ArgParser parser) {
  return [
    'koi_swagger_parser',
    '',
    '用法:',
    '  dart run koi_swagger_parser generate --all',
    '',
    parser.usage,
  ].join('\n');
}