// 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 'package:file_testing/file_testing.dart';
import 'package:flutter_tools/src/base/file_system.dart';
import 'package:flutter_tools/src/base/io.dart';

import '../integration.shard/test_utils.dart';
import '../src/common.dart';

void main() {
  final String flutterBin = fileSystem.path.join(
    getFlutterRoot(),
    'bin',
    'flutter',
  );

  setUpAll(() {
    processManager.runSync(<String>[
      flutterBin,
      'config',
      '--enable-macos-desktop',
    ]);
  });

  for (final String buildMode in <String>['Debug', 'Release']) {
    final String buildModeLower = buildMode.toLowerCase();

    test('flutter build macos --$buildModeLower builds a valid app', () {
      final String workingDirectory = fileSystem.path.join(
        getFlutterRoot(),
        'dev',
        'integration_tests',
        'flutter_gallery',
      );

      processManager.runSync(<String>[
        flutterBin,
        ...getLocalEngineArguments(),
        'clean',
      ], workingDirectory: workingDirectory);

      final File podfile = fileSystem.file(fileSystem.path.join(workingDirectory, 'macos', 'Podfile'));
      final File podfileLock = fileSystem.file(fileSystem.path.join(workingDirectory, 'macos', 'Podfile.lock'));
      expect(podfile, exists);
      expect(podfileLock, exists);

      // Simulate a newer Podfile than Podfile.lock.
      podfile.setLastModifiedSync(DateTime.now());
      podfileLock.setLastModifiedSync(DateTime.now().subtract(const Duration(days: 1)));
      expect(podfileLock.lastModifiedSync().isBefore(podfile.lastModifiedSync()), isTrue);

      final List<String> buildCommand = <String>[
        flutterBin,
        ...getLocalEngineArguments(),
        'build',
        'macos',
        '--$buildModeLower',
      ];
      final ProcessResult result = processManager.runSync(buildCommand, workingDirectory: workingDirectory);

      printOnFailure('Output of flutter build macos:');
      printOnFailure(result.stdout.toString());
      printOnFailure(result.stderr.toString());
      expect(result.exitCode, 0);

      expect(result.stdout, contains('Running pod install'));
      expect(podfile.lastModifiedSync().isBefore(podfileLock.lastModifiedSync()), isTrue);

      final Directory buildPath = fileSystem.directory(fileSystem.path.join(
        workingDirectory,
        'build',
        'macos',
        'Build',
        'Products',
        buildMode,
      ));

      final Directory outputApp = buildPath.childDirectory('flutter_gallery.app');
      final Directory outputAppFramework =
          fileSystem.directory(fileSystem.path.join(
        outputApp.path,
        'Contents',
        'Frameworks',
        'App.framework',
      ));

      final File libBinary = outputAppFramework.childFile('App');
      final File libDsymBinary =
        buildPath.childFile('App.framework.dSYM/Contents/Resources/DWARF/App');

      _checkFatBinary(libBinary, buildModeLower, 'dynamically linked shared library');

      final List<String> libSymbols = AppleTestUtils.getExportedSymbols(libBinary.path);

      if (buildMode == 'Debug') {
        // dSYM is not created for a debug build.
        expect(libDsymBinary.existsSync(), isFalse);
        expect(libSymbols, isEmpty);
      } else {
        _checkFatBinary(libDsymBinary, buildModeLower, 'dSYM companion file');
        expect(libSymbols, equals(AppleTestUtils.requiredSymbols));
        final List<String> dSymSymbols =
            AppleTestUtils.getExportedSymbols(libDsymBinary.path);
        expect(dSymSymbols, containsAll(AppleTestUtils.requiredSymbols));
        // The actual number of symbols is going to vary but there should
        // be "many" in the dSYM. At the time of writing, it was 19195.
        expect(dSymSymbols.length, greaterThanOrEqualTo(15000));
      }

      expect(outputAppFramework.childLink('Resources'), exists);

      final File vmSnapshot = fileSystem.file(fileSystem.path.join(
        outputApp.path,
        'Contents',
        'Frameworks',
        'App.framework',
        'Resources',
        'flutter_assets',
        'vm_snapshot_data',
      ));

      expect(vmSnapshot.existsSync(), buildMode == 'Debug');

      final Directory outputFlutterFramework = fileSystem.directory(
        fileSystem.path.join(
          outputApp.path,
          'Contents',
          'Frameworks',
          'FlutterMacOS.framework',
        ),
      );

      // Check complicated macOS framework symlink structure.
      final Link current = outputFlutterFramework.childDirectory('Versions').childLink('Current');

      expect(current.targetSync(), 'A');

      expect(outputFlutterFramework.childLink('FlutterMacOS').targetSync(),
          fileSystem.path.join('Versions', 'Current', 'FlutterMacOS'));

      expect(outputFlutterFramework.childLink('Resources'), exists);
      expect(outputFlutterFramework.childLink('Resources').targetSync(),
          fileSystem.path.join('Versions', 'Current', 'Resources'));

      expect(outputFlutterFramework.childLink('Headers'), isNot(exists));
      expect(outputFlutterFramework.childDirectory('Headers'), isNot(exists));
      expect(outputFlutterFramework.childLink('Modules'), isNot(exists));
      expect(outputFlutterFramework.childDirectory('Modules'), isNot(exists));

      // Build again without cleaning.
      final ProcessResult secondBuild = processManager.runSync(buildCommand, workingDirectory: workingDirectory);

      printOnFailure('Output of second build:');
      printOnFailure(secondBuild.stdout.toString());
      printOnFailure(secondBuild.stderr.toString());
      expect(secondBuild.exitCode, 0);

      expect(secondBuild.stdout, isNot(contains('Running pod install')));

      processManager.runSync(<String>[
        flutterBin,
        ...getLocalEngineArguments(),
        'clean',
      ], workingDirectory: workingDirectory);
    }, skip: !platform.isMacOS); // [intended] only makes sense for macos platform.
  }
}

void _checkFatBinary(File file, String buildModeLower, String expectedType) {
  final String archs = processManager.runSync(
    <String>['file', file.path],
  ).stdout as String;

  final bool containsX64 = archs.contains('Mach-O 64-bit $expectedType x86_64');
  final bool containsArm = archs.contains('Mach-O 64-bit $expectedType arm64');
  if (buildModeLower == 'debug') {
    // Only build the architecture matching the machine running this test, not both.
    expect(containsX64 ^ containsArm, isTrue, reason: 'Unexpected architecture $archs');
  } else {
    expect(containsX64, isTrue, reason: 'Unexpected architecture $archs');
    expect(containsArm, isTrue, reason: 'Unexpected architecture $archs');
  }
}