StuffProvider.dart

import 'package:emprestimo_objetos/models/stuff.dart';
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';

class StuffProvider {
  static final StuffProvider _instance = StuffProvider.internal();

  factory StuffProvider() => _instance;

  StuffProvider.internal();

  Database _db;

  Future<Database> get db async {
    if (_db != null) {
      return _db;
    } else {
      _db = await initDb();
      return _db;
    }
  }

  Future<Database> initDb() async {
    final databasePath = await getDatabasesPath();
    final path = join(databasePath, "emprestimo_objeto.db");

    return openDatabase(path, version: 1,
        onCreate: (Database db, int newerVersion) async {
      await db.execute("CREATE TABLE $tableStuff("
          "$columnId INTEGER PRIMARY KEY, "
          "$columnFriendName TEXT, "
          "$columnFriendPhone TEXT, "
          "$columnDescription TEXT, "
          "$columnPicture TEXT, "
          "$columnDepartureDate TEXT, "
          "$columnReturnDate TEXT)");
    });
  }

  Future<Stuff> save(Stuff stuff) async {
    Database database = await db;
    stuff.id = await database.insert(tableStuff, stuff.toMap());
    return stuff;
  }

  Future<Stuff> getById(int id) async {
    Database database = await db;
    List<Map> maps = await database.query(tableStuff,
        columns: [
          '$columnId',
          '$columnFriendName',
          '$columnFriendPhone',
          '$columnDescription',
          '$columnPicture',
          '$columnDepartureDate',
          '$columnReturnDate'
        ],
        where: '$columnId = ?',
        whereArgs: [id]);

    if (maps.length > 0) {
      return Stuff.fromMap(maps.first);
    } else {
      return null;
    }
  }

  Future<int> delete(int id) async {
    Database database = await db;
    return await database
        .delete(tableStuff, where: '$columnId = ?', whereArgs: [id]);
  }

  Future<int> update(Stuff stuff) async {
    Database database = await db;
    return await database.update(tableStuff, stuff.toMap(),
        where: '$columnId = ?', whereArgs: [stuff.id]);
  }

  Future<List<Stuff>> getAll() async {
    Database database = await db;
    List listMap = await database.rawQuery("SELECT * FROM $tableStuff");
    List<Stuff> stuffList = listMap.map((x) => Stuff.fromMap(x)).toList();
    return stuffList;
  }

  Future<List<Stuff>> getAllReturnedStuffs() async {
    List<Stuff> stuffList = await getAll();
    return stuffList.where((x) => x.stuffReturnDate != null).toList();
  }

  Future<List<Stuff>> getAllDepartureStuffs() async {
    List<Stuff> stuffList = await getAll();
    return stuffList.where((x) => x.stuffReturnDate == null).toList();
  }

  Future<int> getCount() async {
    Database database = await db;
    return Sqflite.firstIntValue(
        await database.rawQuery("SELECT COUNT(*) FROM $tableStuff"));
  }

  Future close() async {
    Database database = await db;
    database.close();
  }
}