// Copyright 2014 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:convert';
import 'dart:io';
import 'dart:typed_data';

import 'package:archive/archive.dart';
import 'package:flutter_devicelab/framework/apk_utils.dart';
import 'package:flutter_devicelab/framework/framework.dart';
import 'package:flutter_devicelab/framework/task_result.dart';
import 'package:flutter_devicelab/framework/utils.dart';
import 'package:path/path.dart' as path;
import 'package:pub_semver/pub_semver.dart';

final String gradlew = Platform.isWindows ? 'gradlew.bat' : 'gradlew';
final String gradlewExecutable = Platform.isWindows ? '.\\$gradlew' : './$gradlew';
final String fileReadWriteMode = Platform.isWindows ? 'rw-rw-rw-' : 'rw-r--r--';

/// Combines several TaskFunctions with trivial success value into one.
TaskFunction combine(List<TaskFunction> tasks) {
  return () async {
    for (final task in tasks) {
      final TaskResult result = await task();
      if (result.failed) {
        return result;
      }
    }
    return TaskResult.success(null);
  };
}

/// Tests that the Flutter module project template works and supports
/// adding Flutter to an existing Android app.
class ModuleTest {
  ModuleTest({this.gradleVersion = '7.6.3', Version? agpVersion})
    : agpVersion = agpVersion ?? Version(8, 3, 0);

  static const String buildTarget = 'module-gradle';
  // gradleVersion is a String because gradle does not follow dart semver
  // rules for rc candidates.
  final String gradleVersion;
  final Version agpVersion;
  final StringBuffer stdout = StringBuffer();
  final StringBuffer stderr = StringBuffer();

  Future<TaskResult> call() async {
    section('Running: $buildTarget-$gradleVersion');

    section('Find Java');

    final String? javaHome = await findJavaHome();
    if (javaHome == null) {
      return TaskResult.failure('Could not find Java');
    }
    print('\nUsing JAVA_HOME=$javaHome');

    section('Create Flutter module project');

    final Directory tempDir = Directory.systemTemp.createTempSync('flutter_module_test.');
    final projectDir = Directory(path.join(tempDir.path, 'hello'));
    try {
      await inDirectory(tempDir, () async {
        await flutter(
          'create',
          options: <String>['--org', 'io.flutter.devicelab', '--template=module', 'hello'],
          output: stdout,
          stderr: stderr,
        );
      });
      print('Created template in $tempDir.');

      section('Create package with native assets');

      const ffiPackageName = 'ffi_package';
      await createFfiPackage(ffiPackageName, tempDir);

      section('Add FFI package');

      final pubspec = File(path.join(projectDir.path, 'pubspec.yaml'));
      String content = await pubspec.readAsString();
      content = content.replaceFirst(
        'dependencies:${Platform.lineTerminator}',
        'dependencies:${Platform.lineTerminator}  $ffiPackageName:${Platform.lineTerminator}    path: ..${Platform.pathSeparator}$ffiPackageName${Platform.lineTerminator}',
      );
      await pubspec.writeAsString(content, flush: true);
      await inDirectory(projectDir, () async {
        await flutter('packages', options: <String>['get'], output: stdout, stderr: stderr);
      });

      section('Add read-only asset');

      final File readonlyTxtAssetFile = await File(
        path.join(projectDir.path, 'assets', 'read-only.txt'),
      ).create(recursive: true);

      if (!exists(readonlyTxtAssetFile)) {
        return TaskResult.failure('Failed to create read-only asset');
      }

      if (!Platform.isWindows) {
        await exec('chmod', <String>['444', readonlyTxtAssetFile.path]);
      }

      content = content.replaceFirst(
        '${Platform.lineTerminator}  # assets:${Platform.lineTerminator}',
        '${Platform.lineTerminator}  assets:${Platform.lineTerminator}    - assets/read-only.txt${Platform.lineTerminator}',
      );
      await pubspec.writeAsString(content, flush: true);

      section('Add plugins');

      content = content.replaceFirst(
        '${Platform.lineTerminator}dependencies:${Platform.lineTerminator}',
        '${Platform.lineTerminator}dependencies:${Platform.lineTerminator}',
      );
      await pubspec.writeAsString(content, flush: true);
      await inDirectory(projectDir, () async {
        await flutter('packages', options: <String>['get'], output: stdout, stderr: stderr);
      });

      // TODO(dacoharkes): Implement Add2app. https://github.com/flutter/flutter/issues/129757

      section('Build Flutter module library archive');

      await inDirectory(Directory(path.join(projectDir.path, '.android')), () async {
        await exec(
          gradlewExecutable,
          <String>['flutter:assembleDebug'],
          environment: <String, String>{'JAVA_HOME': javaHome},
        );
      });

      final bool aarBuilt = exists(
        File(
          path.join(
            projectDir.path,
            '.android',
            'Flutter',
            'build',
            'outputs',
            'aar',
            'flutter-debug.aar',
          ),
        ),
      );

      if (!aarBuilt) {
        return TaskResult.failure('Failed to build .aar');
      }

      section('Build ephemeral host app');

      await inDirectory(projectDir, () async {
        await flutter('build', options: <String>['apk'], output: stdout, stderr: stderr);
      });

      final bool ephemeralHostApkBuilt = exists(
        File(
          path.join(
            projectDir.path,
            'build',
            'host',
            'outputs',
            'apk',
            'release',
            'app-release.apk',
          ),
        ),
      );

      if (!ephemeralHostApkBuilt) {
        return TaskResult.failure('Failed to build ephemeral host .apk');
      }

      section('Clean build');

      await inDirectory(projectDir, () async {
        await flutter('clean', output: stdout, stderr: stderr);
      });

      section('Build editable host app');

      await inDirectory(projectDir, () async {
        await flutter('build', options: <String>['apk'], output: stdout, stderr: stderr);
      });

      final bool editableHostApkBuilt = exists(
        File(
          path.join(
            projectDir.path,
            'build',
            'host',
            'outputs',
            'apk',
            'release',
            'app-release.apk',
          ),
        ),
      );

      if (!editableHostApkBuilt) {
        return TaskResult.failure('Failed to build editable host .apk');
      }

      section('Flutter build aar succeeds');

      await inDirectory(projectDir, () async {
        await flutter(
          'build',
          options: <String>['aar', '--no-profile'],
          output: stdout,
          stderr: stderr,
        );
      });

      section('Add to existing Android app');

      final hostApp = Directory(path.join(tempDir.path, 'hello_host_app'));
      mkdir(hostApp);
      recursiveCopy(
        Directory(
          path.join(
            flutterDirectory.path,
            'dev',
            'integration_tests',
            'pure_android_host_apps',
            'android_host_app_v2_embedding',
          ),
        ),
        hostApp,
      );
      copy(File(path.join(projectDir.path, '.android', gradlew)), hostApp);
      copy(
        File(path.join(projectDir.path, '.android', 'gradle', 'wrapper', 'gradle-wrapper.jar')),
        Directory(path.join(hostApp.path, 'gradle', 'wrapper')),
      );

      // Modify gradle version to the passed in version.
      final gradleWrapperProperties = File(
        path.join(hostApp.path, 'gradle', 'wrapper', 'gradle-wrapper.properties'),
      );
      String propertyContent = await gradleWrapperProperties.readAsString();
      propertyContent = propertyContent.replaceFirst('REPLACEME', gradleVersion);
      section('Modify gradle wrapper file contents');
      await gradleWrapperProperties.writeAsString(propertyContent, flush: true);

      // Modify AGP version to the passed in version.
      final topBuildDotGradle = File(path.join(hostApp.path, 'build.gradle'));
      String topBuildContent = await topBuildDotGradle.readAsString();
      topBuildContent = topBuildContent.replaceFirst('REPLACEME', agpVersion.toString());
      section(topBuildContent);
      await topBuildDotGradle.writeAsString(topBuildContent, flush: true);

      final bool greaterThanOrEqualToGradle83 = agpVersion.compareTo(Version(8, 3, 0)) >= 0;

      section('Build debug host APK');

      await inDirectory(hostApp, () async {
        if (!Platform.isWindows) {
          await exec('chmod', <String>['+x', 'gradlew']);
        }
        await exec(
          gradlewExecutable,
          <String>['app:assembleDebug'],
          environment: <String, String>{
            'JAVA_HOME': javaHome,
            'FLUTTER_SUPPRESS_ANALYTICS': 'true',
          },
        );
      });

      section('Check debug APK exists');

      final String debugHostApk = path.join(
        hostApp.path,
        'app',
        'build',
        'outputs',
        'apk',
        'debug',
        'app-debug.apk',
      );
      if (!exists(File(debugHostApk))) {
        return TaskResult.failure('Failed to build debug host APK');
      }

      section('Check files in debug APK');

      checkCollectionContains<String>(<String>[
        ...flutterAssets,
        ...debugAssets,
        ...baseApkFiles,
        'lib/arm64-v8a/lib$ffiPackageName.so',
        'lib/armeabi-v7a/lib$ffiPackageName.so',
      ], await getFilesInApk(debugHostApk));

      section('Check debug AndroidManifest.xml');

      final String androidManifestDebug = await getAndroidManifest(debugHostApk);
      if (!androidManifestDebug.contains('''
        <meta-data
            android:name="flutterProjectType"
            android:value="module" />''')) {
        return TaskResult.failure(
          "Debug host APK doesn't contain metadata: flutterProjectType = module ",
        );
      }

      section('Check file access modes for Debug read-only asset from Flutter module');

      final String readonlyDebugAssetFilePath = path.joinAll(<String>[
        hostApp.path,
        'app',
        'build',
        'intermediates',
        'assets',
        'debug',
        ...greaterThanOrEqualToGradle83 ? <String>['mergeDebugAssets'] : <String>[],
        'flutter_assets',
        'assets',
        'read-only.txt',
      ]);
      // ./app/build/intermediates/assets/debug/mergeDebugAssets/flutter_assets/assets/read-only.txt
      final readonlyDebugAssetFile = File(readonlyDebugAssetFilePath);
      if (!exists(readonlyDebugAssetFile)) {
        return TaskResult.failure('Failed to copy read-only debug asset file');
      }

      String modes = readonlyDebugAssetFile.statSync().modeString();
      print('\nread-only.txt file access modes = $modes');
      if (modes.compareTo(fileReadWriteMode) != 0) {
        return TaskResult.failure('Failed to make assets user-readable and writable');
      }

      section('Build release host APK');

      await inDirectory(hostApp, () async {
        await exec(
          gradlewExecutable,
          <String>['app:assembleRelease'],
          environment: <String, String>{
            'JAVA_HOME': javaHome,
            'FLUTTER_SUPPRESS_ANALYTICS': 'true',
          },
        );
      });

      final String releaseHostApk = path.join(
        hostApp.path,
        'app',
        'build',
        'outputs',
        'apk',
        'release',
        'app-release-unsigned.apk',
      );
      if (!exists(File(releaseHostApk))) {
        return TaskResult.failure('Failed to build release host APK');
      }

      section('Check files in release APK');

      checkCollectionContains<String>(<String>[
        ...flutterAssets,
        ...baseApkFiles,
        'lib/arm64-v8a/lib$ffiPackageName.so',
        'lib/arm64-v8a/libapp.so',
        'lib/arm64-v8a/libflutter.so',
        'lib/armeabi-v7a/lib$ffiPackageName.so',
        'lib/armeabi-v7a/libapp.so',
        'lib/armeabi-v7a/libflutter.so',
      ], await getFilesInApk(releaseHostApk));

      section('Check the NOTICE file is correct');

      await inDirectory(hostApp, () async {
        final apkFile = File(releaseHostApk);
        final Archive apk = ZipDecoder().decodeBytes(apkFile.readAsBytesSync());
        // Shouldn't be missing since we already checked it exists above.
        final ArchiveFile? noticesFile = apk.findFile('assets/flutter_assets/NOTICES.Z');

        final licenseData = noticesFile?.content as Uint8List?;
        if (licenseData == null) {
          return TaskResult.failure('Invalid license file.');
        }
        final String licenseString = utf8.decode(gzip.decode(licenseData));
        if (!licenseString.contains('skia') || !licenseString.contains('Flutter Authors')) {
          return TaskResult.failure('License content missing.');
        }
      });

      section('Check release AndroidManifest.xml');

      final String androidManifestRelease = await getAndroidManifest(debugHostApk);
      if (!androidManifestRelease.contains('''
        <meta-data
            android:name="flutterProjectType"
            android:value="module" />''')) {
        return TaskResult.failure(
          "Release host APK doesn't contain metadata: flutterProjectType = module ",
        );
      }

      section('Check file access modes for release read-only asset from Flutter module');

      final String readonlyReleaseAssetFilePath = path.joinAll(<String>[
        hostApp.path,
        'app',
        'build',
        'intermediates',
        'assets',
        'release',
        ...greaterThanOrEqualToGradle83 ? <String>['mergeReleaseAssets'] : <String>[],
        'flutter_assets',
        'assets',
        'read-only.txt',
      ]);
      final readonlyReleaseAssetFile = File(readonlyReleaseAssetFilePath);
      if (!exists(readonlyReleaseAssetFile)) {
        return TaskResult.failure('Failed to copy read-only release asset file');
      }

      modes = readonlyReleaseAssetFile.statSync().modeString();
      print('\nread-only.txt file access modes = $modes');
      if (modes.compareTo(fileReadWriteMode) != 0) {
        return TaskResult.failure('Failed to make assets user-readable and writable');
      }

      section('Check for specific log errors.');
      final finalStderr = stderr.toString();
      if (finalStderr.contains("You are applying Flutter's main Gradle plugin imperatively")) {
        return TaskResult.failure('Applied the Flutter Gradle Plugin imperatively');
      }

      return TaskResult.success(null);
    } on TaskResult catch (taskResult) {
      return taskResult;
    } catch (e, stackTrace) {
      print('Task exception stack trace:\n$stackTrace');
      return TaskResult.failure(e.toString());
    } finally {
      rmTree(tempDir);
    }
  }
}

Future<void> main() async {
  await task(
    combine(<TaskFunction>[
      // 3 tests comes close to timeout.
      // Pre AGP 8.3
      ModuleTest(gradleVersion: '8.4', agpVersion: Version.parse('8.2.1')).call,
      // Post AGP 8.3 + rc candidates can work
      ModuleTest(gradleVersion: '8.13-rc-1', agpVersion: Version.parse('8.8.1')).call,
    ]),
  );
}