import 'dart:convert';
import 'dart:io';

import 'package:encrypt/encrypt.dart';
import 'package:manager_app/Models/session.dart';
import 'package:path_provider/path_provider.dart';

class SessionHelper {
  final key = Key.fromUtf8('aVs:ZMe3EK-yS<y:;k>vCGrj3T8]yG6E');
  final iv = IV.fromLength(16);


  Future<String> get _localPath async {
    final directory = await getApplicationDocumentsDirectory();

    return directory.path;
  }

  Future<File> get _localFile async {
    final path = await _localPath;
    return File('$path/session.json');
  }

  Future<File> writeSession(Session session) async {
    final file = await _localFile;

    if (session.password != null) {
      var encrypter = Encrypter(AES(key));
      var encrypted = encrypter.encrypt(session.password, iv: iv);

      session.password = encrypted.base64;
    }
    // Write the file
    return file.writeAsString(jsonEncode(session.toMap()));
  }

  Future<Session> readSession() async {
    try {
      final file = await _localFile;
      // Read the file
      final contents = await file.readAsString();

      Session session = Session.fromJson(jsonDecode(contents));

      var encrypter = Encrypter(AES(key));

      if (session.password != null) {
        session.password = encrypter.decrypt64(session.password, iv: iv);
      }

      return session;
    } catch (e) {
      if (e.toString().contains("cannot find the file")) {
        final path = await _localPath;
        new File('$path/session.json').createSync(recursive: true);
        print("file created");
        await writeSession(new Session(rememberMe: false));
      }
      // If encountering an error, return 0
      return Session(rememberMe: false);
    }
  }
}