// Copyright 2013 The Flutter Authors. 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' as io;

import 'package:file/file.dart';
import 'package:path/path.dart' as p;
import 'package:uuid/uuid.dart';

import 'common/core.dart';
import 'common/package_looping_command.dart';
import 'common/process_runner.dart';

/// A command to run tests via Firebase test lab.
class FirebaseTestLabCommand extends PackageLoopingCommand {
  /// Creates an instance of the test runner command.
  FirebaseTestLabCommand(
    Directory packagesDir, {
    ProcessRunner processRunner = const ProcessRunner(),
  }) : super(packagesDir, processRunner: processRunner) {
    argParser.addOption(
      'project',
      defaultsTo: 'flutter-infra',
      help: 'The Firebase project name.',
    );
    final String? homeDir = io.Platform.environment['HOME'];
    argParser.addOption('service-key',
        defaultsTo:
            homeDir == null ? null : p.join(homeDir, 'gcloud-service-key.json'),
        help: 'The path to the service key for gcloud authentication.\n'
            r'If not provided, \$HOME/gcloud-service-key.json will be '
            r'assumed if $HOME is set.');
    argParser.addOption('test-run-id',
        defaultsTo: const Uuid().v4(),
        help:
            'Optional string to append to the results path, to avoid conflicts. '
            'Randomly chosen on each invocation if none is provided. '
            'The default shown here is just an example.');
    argParser.addOption('build-id',
        defaultsTo:
            io.Platform.environment['CIRRUS_BUILD_ID'] ?? 'unknown_build',
        help:
            'Optional string to append to the results path, to avoid conflicts. '
            r'Defaults to $CIRRUS_BUILD_ID if that is set.');
    argParser.addMultiOption('device',
        splitCommas: false,
        defaultsTo: <String>[
          'model=walleye,version=26',
          'model=flame,version=29'
        ],
        help:
            'Device model(s) to test. See https://cloud.google.com/sdk/gcloud/reference/firebase/test/android/run for more info');
    argParser.addOption('results-bucket',
        defaultsTo: 'gs://flutter_firebase_testlab');
    argParser.addOption(
      kEnableExperiment,
      defaultsTo: '',
      help: 'Enables the given Dart SDK experiments.',
    );
  }

  @override
  final String name = 'firebase-test-lab';

  @override
  final String description = 'Runs the instrumentation tests of the example '
      'apps on Firebase Test Lab.\n\n'
      'Runs tests in test_instrumentation folder using the '
      'instrumentation_test package.';

  static const String _gradleWrapper = 'gradlew';

  Completer<void>? _firebaseProjectConfigured;

  Future<void> _configureFirebaseProject() async {
    if (_firebaseProjectConfigured != null) {
      return _firebaseProjectConfigured!.future;
    }
    _firebaseProjectConfigured = Completer<void>();

    final String serviceKey = getStringArg('service-key');
    if (serviceKey.isEmpty) {
      print('No --service-key provided; skipping gcloud authorization');
    } else {
      await processRunner.run(
        'gcloud',
        <String>[
          'auth',
          'activate-service-account',
          '--key-file=$serviceKey',
        ],
        exitOnError: true,
        logOnError: true,
      );
      final int exitCode = await processRunner.runAndStream('gcloud', <String>[
        'config',
        'set',
        'project',
        getStringArg('project'),
      ]);
      if (exitCode == 0) {
        print('\nFirebase project configured.');
        return;
      } else {
        print(
            '\nWarning: gcloud config set returned a non-zero exit code. Continuing anyway.');
      }
    }
    _firebaseProjectConfigured!.complete(null);
  }

  @override
  Future<List<String>> runForPackage(Directory package) async {
    if (!package
        .childDirectory('example')
        .childDirectory('android')
        .childDirectory('app')
        .childDirectory('src')
        .childDirectory('androidTest')
        .existsSync()) {
      printSkip('No example with androidTest directory');
      return PackageLoopingCommand.success;
    }

    final List<String> errors = <String>[];

    final Directory exampleDirectory = package.childDirectory('example');
    final Directory androidDirectory =
        exampleDirectory.childDirectory('android');

    // Ensures that gradle wrapper exists
    if (!await _ensureGradleWrapperExists(androidDirectory)) {
      errors.add('Unable to build example apk');
      return errors;
    }

    await _configureFirebaseProject();

    if (!await _runGradle(androidDirectory, 'app:assembleAndroidTest')) {
      errors.add('Unable to assemble androidTest');
      return errors;
    }

    // Used within the loop to ensure a unique GCS output location for each
    // test file's run.
    int resultsCounter = 0;
    for (final File test in _findIntegrationTestFiles(package)) {
      final String testName = p.relative(test.path, from: package.path);
      print('Testing $testName...');
      if (!await _runGradle(androidDirectory, 'app:assembleDebug',
          testFile: test)) {
        printError('Could not build $testName');
        errors.add('$testName failed to build');
        continue;
      }
      final String buildId = getStringArg('build-id');
      final String testRunId = getStringArg('test-run-id');
      final String resultsDir =
          'plugins_android_test/${getPackageDescription(package)}/$buildId/$testRunId/${resultsCounter++}/';
      final List<String> args = <String>[
        'firebase',
        'test',
        'android',
        'run',
        '--type',
        'instrumentation',
        '--app',
        'build/app/outputs/apk/debug/app-debug.apk',
        '--test',
        'build/app/outputs/apk/androidTest/debug/app-debug-androidTest.apk',
        '--timeout',
        '5m',
        '--results-bucket=${getStringArg('results-bucket')}',
        '--results-dir=$resultsDir',
      ];
      for (final String device in getStringListArg('device')) {
        args.addAll(<String>['--device', device]);
      }
      final int exitCode = await processRunner.runAndStream('gcloud', args,
          workingDir: exampleDirectory);

      if (exitCode != 0) {
        printError('Test failure for $testName');
        errors.add('$testName failed tests');
      }
    }
    return errors;
  }

  /// Checks that 'gradlew' exists in [androidDirectory], and if not runs a
  /// Flutter build to generate it.
  ///
  /// Returns true if either gradlew was already present, or the build succeeds.
  Future<bool> _ensureGradleWrapperExists(Directory androidDirectory) async {
    if (!androidDirectory.childFile(_gradleWrapper).existsSync()) {
      print('Running flutter build apk...');
      final String experiment = getStringArg(kEnableExperiment);
      final int exitCode = await processRunner.runAndStream(
          'flutter',
          <String>[
            'build',
            'apk',
            if (experiment.isNotEmpty) '--enable-experiment=$experiment',
          ],
          workingDir: androidDirectory);

      if (exitCode != 0) {
        return false;
      }
    }
    return true;
  }

  /// Builds [target] using 'gradlew' in the given [directory]. Assumes
  /// 'gradlew' already exists.
  ///
  /// [testFile] optionally does the Flutter build with the given test file as
  /// the build target.
  ///
  /// Returns true if the command succeeds.
  Future<bool> _runGradle(
    Directory directory,
    String target, {
    File? testFile,
  }) async {
    final String experiment = getStringArg(kEnableExperiment);
    final String? extraOptions = experiment.isNotEmpty
        ? Uri.encodeComponent('--enable-experiment=$experiment')
        : null;

    final int exitCode = await processRunner.runAndStream(
        p.join(directory.path, _gradleWrapper),
        <String>[
          target,
          '-Pverbose=true',
          if (testFile != null) '-Ptarget=${testFile.path}',
          if (extraOptions != null) '-Pextra-front-end-options=$extraOptions',
          if (extraOptions != null)
            '-Pextra-gen-snapshot-options=$extraOptions',
        ],
        workingDir: directory);

    if (exitCode != 0) {
      return false;
    }
    return true;
  }

  /// Finds and returns all integration test files for [package].
  Iterable<File> _findIntegrationTestFiles(Directory package) sync* {
    final Directory integrationTestDir =
        package.childDirectory('example').childDirectory('integration_test');

    if (!integrationTestDir.existsSync()) {
      return;
    }

    yield* integrationTestDir
        .listSync(recursive: true, followLinks: true)
        .where((FileSystemEntity file) =>
            file is File && file.basename.endsWith('_test.dart'))
        .cast<File>();
  }
}