import 'package:sqflite/sqflite.dart';
import 'package:path/path.dart';

final String table = "contactTable";
final String idColumn = "idColumn";
final String nameColumn = "nameColumn";
final String emailColumn = "emailColumn";
final String phoneColumn = "phoneColumn";
final String imgColumn = "imgColumn";

class ContactHelper {
  static final ContactHelper _instance = ContactHelper.internal();
  factory ContactHelper() => _instance;
  ContactHelper.internal();

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

  Future<Database> initDb() async {
    final databasesPath = await getDatabasesPath();
    final path = join(databasesPath, "contacts.db");
    return await openDatabase(path, version: 1,
        onCreate: (Database db, int newerVersion) async {
      await db.execute('''CREATE TABLE $table (
          $idColumn INTEGER PRIMARY KEY,
          $nameColumn TEXT,
          $emailColumn TEXT,
          $phoneColumn TEXT,
          $imgColumn TEXT
        )''');
    });
  }

  Future<Contact> saveContact(Contact contact) async {
    Database dbContact = await this.db;
    contact.id = await dbContact.insert(table, contact.toMap());
    return contact;
  }

  Future<Contact> getContact(int id) async {
    Database dbContact = await this.db;
    List<Map> maps = await dbContact.query(table,
        columns: [
          idColumn,
          nameColumn,
          emailColumn,
          phoneColumn,
          imgColumn,
        ],
        where: "$idColumn = ?",
        whereArgs: [id]);
    if (maps.length > 0) {
      return Contact.fromMap(maps.first);
    } else {
      return null;
    }
  }

  Future<List<Contact>> getAll() async {
    Database dbContact = await this.db;
    List<Map> maps = await dbContact.rawQuery("SELECT * FROM $table");
    List<Contact> list = List<Contact>();
    for (Map m in maps) {
      list.add(Contact.fromMap(m));
    }
    return list;
  }

  Future<int> deleteContact(int id) async {
    Database dbContact = await this.db;
    return await dbContact.delete(table, where: "$idColumn = ?", whereArgs: [id]);
  }

  Future<int> updateContact(Contact contact) async {
     Database dbContact = await this.db;
     return await dbContact.update(table, contact.toMap(), where: "$idColumn = ?", whereArgs: [contact.id]);
  }

  Future<int> getNumber() async {
    Database dbContact = await this.db;
    return Sqflite.firstIntValue(await dbContact.rawQuery("SELECT COUNT(*) FROM $table"));
  }

  Future closer() async {
    Database dbContact = await this.db;
    dbContact.close();
  }
}

class Contact {
  int id;
  String name;
  String email;
  String phone;
  String img;

  Contact();

  Contact.fromMap(Map map) {
    this.id = map[idColumn];
    this.name = map[nameColumn];
    this.email = map[emailColumn];
    this.phone = map[phoneColumn];
    this.img = map[imgColumn];
  }

  Map toMap() {
    Map<String, dynamic> maps = {
      nameColumn: this.name,
      emailColumn: this.email,
      phoneColumn: this.phone,
      imgColumn: this.img,
    };
    if (this.id != null) maps[idColumn] = this.id;
    return maps;
  }

  @override
  String toString() {
    return "Contact: id = $id, name = $name, email = $email, phone = $phone, img = $img";
  }
}