// Copyright (c) 2023, 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 'dart:async';
import 'dart:io';

Future<void> compilePerfettoProtos() async {
  final processResult = await Process.run(
    './tools/build.py',
    [
      '-mdebug',
      '-ax64',
      'runtime/vm:perfetto_protos_protozero',
      'runtime/vm:perfetto_protos_dart'
    ],
  );

  final int exitCode = processResult.exitCode;
  final String stdout = processResult.stdout.trim();
  final String stderr = processResult.stderr.trim();
  if (exitCode != 0) {
    print('exit-code: $exitCode');
    print('stdout:');
    print('${stdout}');
    print('stderr:');
    print('${stderr}');
  }
}

const noticesToPrepend = r'''
// Copyright (c) 2023, 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.

// IMPORTANT: This file should only ever be modified by modifying the
// corresponding .proto file and then running
// `dart runtime/vm/protos/tools/compile_perfetto_protos.dart` from the SDK root
// directory.
''';

Future<void> copyGeneratedFiles(
    {required Directory source, required Directory destination}) async {
  final executable = 'cp';
  final args = ['-R', source.path, destination.path];
  final processResult = await Process.run(executable, args);

  final int exitCode = processResult.exitCode;
  final String stdout = processResult.stdout.trim();
  final String stderr = processResult.stderr.trim();
  if (exitCode != 0) {
    print('exit-code: $exitCode');
    print('stdout:');
    print('${stdout}');
    print('stderr:');
    print('${stderr}');
  }

  for (final file
      in Directory('${destination.path}/protos').listSync(recursive: true)) {
    if (!(file is File &&
        (file.path.endsWith('.pbzero.h') ||
            file.path.endsWith('.pb.dart') ||
            file.path.endsWith('.pbenum.dart') ||
            file.path.endsWith('.pbjson.dart') ||
            file.path.endsWith('.pbserver.dart')))) {
      continue;
    }
    if (file.path.endsWith('.pbenum.dart') &&
        file.readAsStringSync().indexOf('class') == -1) {
      // Sometimes .pbenum.dart files that are effictively empty get generated,
      // so we delete them.
      file.deleteSync();
      continue;
    }

    final contentsIncludingPrependedNotices =
        noticesToPrepend + file.readAsStringSync();
    file.writeAsStringSync(contentsIncludingPrependedNotices, flush: true);
  }
}

void createFileThatExportsAllGeneratedDartCode() {
  final file = File('./pkg/vm_service_protos/lib/vm_service_protos.dart');
  if (!file.existsSync()) {
    file.createSync();
  }
  file.writeAsStringSync(noticesToPrepend + '\n');

  final generatedDartFilePaths =
      Directory('./pkg/vm_service_protos/lib/src/protos/perfetto')
          .listSync(recursive: true)
          .where((entity) => entity is File)
          .map((file) => file.path)
          .toList();
  generatedDartFilePaths.sort();
  for (final path in generatedDartFilePaths) {
    final pathToExport = path.replaceAll('./pkg/vm_service_protos/lib/', '');
    file.writeAsStringSync("export '$pathToExport';\n", mode: FileMode.append);
  }
}

main(List<String> files) async {
  if (!Directory('./runtime/vm').existsSync()) {
    print('Error: this tool must be run from the root directory of the SDK.');
    return;
  }
  if (!Platform.isLinux) {
    // TODO(derekx): The compilation of protoc fails on MacOS due to the error
    // "'sprintf' is deprecated". When bumping protobuf, check if this problem
    // has been resolved.
    print('Error: this tool can only be run on Linux because protoc has '
        'compatibility issues on other platforms.');
    return;
  }

  await compilePerfettoProtos();
  await copyGeneratedFiles(
    destination: Directory('./runtime/vm'),
    source: Directory('./out/DebugX64/gen/runtime/vm/protos'),
  );
  await copyGeneratedFiles(
    destination: Directory('./pkg/vm_service_protos/lib/src'),
    source:
        Directory('./out/DebugX64/gen/pkg/vm_service_protos/lib/src/protos'),
  );
  createFileThatExportsAllGeneratedDartCode();
}