import 'dart:ffi';
import 'dart:io';
import 'package:test/test.dart';
import 'package:libgit2dart/libgit2dart.dart';
import 'helpers/util.dart';

void main() {
  late Repository repo;
  late Index index;
  late Directory tmpDir;

  setUp(() {
    tmpDir = setupRepo(Directory('test/assets/testrepo/'));
    repo = Repository.open(tmpDir.path);
    index = repo.index;
  });

  tearDown(() {
    index.free();
    repo.free();
    tmpDir.deleteSync(recursive: true);
  });

  group('Index', () {
    const fileSha = 'e69de29bb2d1d6434b8b29ae775ad8c2e48c5391';
    const featureFileSha = '9c78c21d6680a7ffebc76f7ac68cacc11d8f48bc';

    test('returns number of entries', () {
      expect(index.length, 4);
    });

    test('returns mode of index entry', () {
      for (final entry in index) {
        expect(entry.mode, GitFilemode.blob);
      }
    });

    test('returns index entry at provided position', () {
      expect(index[3].path, 'file');
      expect(index[3].sha, fileSha);
    });

    test('returns index entry at provided path', () {
      expect(index['file'].path, 'file');
      expect(index['file'].sha, fileSha);
    });

    test('throws if provided entry position is out of bounds', () {
      expect(() => index[10], throwsA(isA<RangeError>()));
    });

    test('throws if provided entry path is not found', () {
      expect(() => index[10], throwsA(isA<ArgumentError>()));
    });

    test('successfully changes attributes', () {
      final entry = index['file'];
      final otherEntry = index['feature_file'];

      expect(entry.oid == otherEntry.oid, false);
      expect(entry.mode, isNot(GitFilemode.blobExecutable));

      entry.path = 'some.txt';
      entry.oid = otherEntry.oid;
      entry.mode = GitFilemode.blobExecutable;

      expect(entry.path, 'some.txt');
      expect(entry.oid == otherEntry.oid, true);
      expect(entry.mode, GitFilemode.blobExecutable);
    });

    test('clears the contents', () {
      expect(index.length, 4);
      index.clear();
      expect(index.length, 0);
    });

    test('throws when trying to clear the contents and error occurs', () {
      expect(
        () => Index(nullptr).clear(),
        throwsA(
          isA<LibGit2Error>().having(
            (e) => e.toString(),
            'error',
            "invalid argument: 'index'",
          ),
        ),
      );
    });

    group('add()', () {
      test('successfully adds with provided IndexEntry', () {
        final entry = index['file'];

        index.add(entry);
        expect(index['file'].sha, fileSha);
        expect(index.length, 4);
      });

      test('successfully adds with provided path string', () {
        index.add('file');
        expect(index['file'].sha, fileSha);
        expect(index.length, 4);
      });

      test('throws if file not found at provided path', () {
        expect(
          () => index.add('not_there'),
          throwsA(
            isA<LibGit2Error>().having(
              (e) => e.toString(),
              'error',
              "could not find '${repo.workdir}not_there' to stat: No such file or directory",
            ),
          ),
        );
      });

      test('throws if provided IndexEntry is invalid', () {
        expect(
          () => index.add(IndexEntry(nullptr)),
          throwsA(
            isA<LibGit2Error>().having(
              (e) => e.toString(),
              'error',
              "invalid argument: 'source_entry && source_entry->path'",
            ),
          ),
        );
      });

      test('throws if index of bare repository', () {
        final bare = Repository.open('test/assets/empty_bare.git');
        final bareIndex = bare.index;

        expect(
          () => bareIndex.add('config'),
          throwsA(
            isA<LibGit2Error>().having(
              (e) => e.toString(),
              'error',
              "cannot create blob from file. This operation is not allowed against bare repositories.",
            ),
          ),
        );

        bareIndex.free();
        bare.free();
      });
    });

    group('addAll()', () {
      test('successfully adds with provided pathspec', () {
        index.clear();
        index.addAll(['file', 'feature_file']);

        expect(index.length, 2);
        expect(index['file'].sha, fileSha);
        expect(index['feature_file'].sha, featureFileSha);

        index.clear();
        index.addAll(['[f]*']);

        expect(index.length, 2);
        expect(index['file'].sha, fileSha);
        expect(index['feature_file'].sha, featureFileSha);

        index.clear();
        index.addAll(['feature_f???']);

        expect(index.length, 1);
        expect(index['feature_file'].sha, featureFileSha);
      });

      test('throws when trying to addAll in bare repository', () {
        final bare = Repository.open('test/assets/empty_bare.git');
        final bareIndex = bare.index;

        expect(
          () => bareIndex.addAll([]),
          throwsA(
            isA<LibGit2Error>().having(
              (e) => e.toString(),
              'error',
              "cannot index add all. This operation is not allowed against bare repositories.",
            ),
          ),
        );

        bareIndex.free();
        bare.free();
      });
    });

    test('writes to disk', () {
      expect(index.length, 4);

      File('${tmpDir.path}/new_file').createSync();

      index.add('new_file');
      index.write();

      index.clear();
      index.read();
      expect(index['new_file'].path, 'new_file');
      expect(index.length, 5);
    });

    test('removes an entry', () {
      expect(index.find('feature_file'), true);
      index.remove('feature_file');
      expect(index.find('feature_file'), false);
    });

    test('throws when trying to remove entry with invalid path', () {
      expect(
        () => index.remove('invalid'),
        throwsA(
          isA<LibGit2Error>().having(
            (e) => e.toString(),
            'error',
            "index does not contain invalid at stage 0",
          ),
        ),
      );
    });

    test('removes all entries with matching pathspec', () {
      expect(index.find('file'), true);
      expect(index.find('feature_file'), true);

      index.removeAll(['[f]*']);

      expect(index.find('file'), false);
      expect(index.find('feature_file'), false);
    });

    test('successfully reads tree with provided SHA hex', () {
      final tree = repo.lookupTree(
        repo['df2b8fc99e1c1d4dbc0a854d9f72157f1d6ea078'],
      );
      expect(index.length, 4);
      index.readTree(tree);

      expect(index.length, 1);

      // make sure the index is only modified in memory
      index.read();
      expect(index.length, 4);
    });

    test('successfully writes tree', () {
      final oid = index.writeTree();
      expect(oid.sha, 'a8ae3dd59e6e1802c6f78e05e301bfd57c9f334f');
    });

    test('throws when trying to write tree to invalid repository', () {
      expect(
        () => index.writeTree(Repository(nullptr)),
        throwsA(
          isA<LibGit2Error>().having(
            (e) => e.toString(),
            'error',
            "invalid argument: 'repo'",
          ),
        ),
      );
    });

    test('throws when trying to write tree while index have conflicts', () {
      final tmpDir = setupRepo(Directory('test/assets/mergerepo/'));
      final repo = Repository.open(tmpDir.path);

      final conflictBranch = repo.lookupBranch(name: 'conflict-branch');
      final index = repo.index;
      repo.merge(conflictBranch.target);

      expect(
        () => index.writeTree(),
        throwsA(
          isA<LibGit2Error>().having(
            (e) => e.toString(),
            'error',
            "cannot create a tree from a not fully merged index.",
          ),
        ),
      );

      conflictBranch.free();
      index.free();
      repo.free();
      tmpDir.deleteSync(recursive: true);
    });

    test('returns conflicts with ancestor, our and their present', () {
      final repoDir = setupRepo(Directory('test/assets/mergerepo/'));
      final conflictRepo = Repository.open(repoDir.path);

      final conflictBranch = conflictRepo.lookupBranch(
        name: 'ancestor-conflict',
      );

      conflictRepo.checkout(refName: 'refs/heads/feature');

      conflictRepo.merge(conflictBranch.target);

      final index = conflictRepo.index;
      final conflictedFile = index.conflicts['feature_file']!;
      expect(conflictedFile.ancestor?.path, 'feature_file');
      expect(conflictedFile.our?.path, 'feature_file');
      expect(conflictedFile.their?.path, 'feature_file');
      expect(conflictedFile.toString(), contains('ConflictEntry{'));

      index.free();
      conflictBranch.free();
      conflictRepo.free();
      repoDir.deleteSync(recursive: true);
    });

    test('returns conflicts with our and their present and null ancestor', () {
      final repoDir = setupRepo(Directory('test/assets/mergerepo/'));
      final conflictRepo = Repository.open(repoDir.path);

      final conflictBranch = conflictRepo.lookupBranch(name: 'conflict-branch');

      conflictRepo.merge(conflictBranch.target);

      final index = conflictRepo.index;
      final conflictedFile = index.conflicts['conflict_file']!;
      expect(conflictedFile.ancestor?.path, null);
      expect(conflictedFile.our?.path, 'conflict_file');
      expect(conflictedFile.their?.path, 'conflict_file');
      expect(conflictedFile.toString(), contains('ConflictEntry{'));

      index.free();
      conflictBranch.free();
      conflictRepo.free();
      repoDir.deleteSync(recursive: true);
    });

    test('returns conflicts with ancestor and their present and null our', () {
      final repoDir = setupRepo(Directory('test/assets/mergerepo/'));
      final conflictRepo = Repository.open(repoDir.path);

      final conflictBranch = conflictRepo.lookupBranch(
        name: 'ancestor-conflict',
      );

      conflictRepo.checkout(refName: 'refs/heads/our-conflict');

      conflictRepo.merge(conflictBranch.target);

      final index = conflictRepo.index;
      final conflictedFile = index.conflicts['feature_file']!;
      expect(conflictedFile.ancestor?.path, 'feature_file');
      expect(conflictedFile.our?.path, null);
      expect(conflictedFile.their?.path, 'feature_file');
      expect(conflictedFile.toString(), contains('ConflictEntry{'));

      index.free();
      conflictBranch.free();
      conflictRepo.free();
      repoDir.deleteSync(recursive: true);
    });

    test('returns conflicts with ancestor and our present and null their', () {
      final repoDir = setupRepo(Directory('test/assets/mergerepo/'));
      final conflictRepo = Repository.open(repoDir.path);

      final conflictBranch = conflictRepo.lookupBranch(name: 'their-conflict');

      conflictRepo.checkout(refName: 'refs/heads/feature');

      conflictRepo.merge(conflictBranch.target);

      final index = conflictRepo.index;
      final conflictedFile = index.conflicts['feature_file']!;
      expect(conflictedFile.ancestor?.path, 'feature_file');
      expect(conflictedFile.our?.path, 'feature_file');
      expect(conflictedFile.their?.path, null);
      expect(conflictedFile.toString(), contains('ConflictEntry{'));

      index.free();
      conflictBranch.free();
      conflictRepo.free();
      repoDir.deleteSync(recursive: true);
    });

    test('successfully removes conflicts', () {
      final repoDir = setupRepo(Directory('test/assets/mergerepo/'));
      final conflictRepo = Repository.open(repoDir.path);

      final conflictBranch = conflictRepo.lookupBranch(name: 'conflict-branch');
      final index = conflictRepo.index;

      conflictRepo.merge(conflictBranch.target);
      expect(index.hasConflicts, true);
      expect(index.conflicts.length, 1);

      final conflictedFile = index.conflicts['conflict_file']!;
      conflictedFile.remove();
      expect(index.hasConflicts, false);
      expect(index.conflicts, isEmpty);
      expect(index.conflicts['conflict_file'], null);

      index.free();
      conflictBranch.free();
      conflictRepo.free();
      repoDir.deleteSync(recursive: true);
    });

    test('throws when trying to remove conflict and error occurs', () {
      expect(
        () => ConflictEntry(index.pointer, 'invalid.path', null, null, null)
            .remove(),
        throwsA(
          isA<LibGit2Error>().having(
            (e) => e.toString(),
            'error',
            "index does not contain invalid.path",
          ),
        ),
      );
    });

    test('returns string representation of Index and IndexEntry objects', () {
      final index = repo.index;

      expect(index.toString(), contains('Index{'));
      expect(index['file'].toString(), contains('IndexEntry{'));

      index.free();
    });
  });
}