refactored code

lib/src/binding.dart

@@ -0,0 +1,120 @@
+///
+/// Copyright 2021 Sergey Penkovsky <sergey.penkovsky@gmail.com>
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///      http://www.apache.org/licenses/LICENSE-2.0
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+
+enum Mode { SIMPLE, INSTANCE, PROVIDER_INSTANCE }
+
+/// RU: Класс Binding<T> настраивает параметры экземпляра.
+/// ENG: The Binding<T> class configures the settings for the instance.
+///
+class Binding<T> {
+  late Mode _mode;
+  late Type _key;
+  late String _name;
+  T? _instance;
+  T? Function()? _provider;
+  late bool _isSingeltone = false;
+  late bool _isNamed = false;
+
+  Binding() {
+    _mode = Mode.SIMPLE;
+    _key = T;
+  }
+
+  /// RU: Метод возвращает [Mode] экземпляра.
+  /// ENG: The method returns the [Mode] of the instance.
+  ///
+  /// return [Mode]
+  Mode get mode => _mode;
+
+  /// RU: Метод возвращает тип экземпляра.
+  /// ENG: The method returns the type of the instance.
+  ///
+  /// return [Type]
+  Type get key => _key;
+
+  /// RU: Метод возвращает имя экземпляра.
+  /// ENG: The method returns the name of the instance.
+  ///
+  /// return [String]
+  String get name => _name;
+
+  /// RU: Метод проверяет сингелтон экземпляр или нет.
+  /// ENG: The method checks the singleton instance or not.
+  ///
+  /// return [bool]
+  bool get isSingeltone => _isSingeltone;
+
+  /// RU: Метод проверяет именован экземпляр или нет.
+  /// ENG: The method checks whether the instance is named or not.
+  ///
+  /// return [bool]
+  bool get isNamed => _isNamed;
+
+  /// RU: Добавляет имя для экземляпя [value].
+  /// ENG: Added name for instance [value].
+  ///
+  /// return [Binding]
+  Binding<T> withName(String name) {
+    _name = name;
+    _isNamed = true;
+    return this;
+  }
+
+  /// RU: Инициализация экземляпяра [value].
+  /// ENG: Initialization instance [value].
+  ///
+  /// return [Binding]
+  Binding<T> toInstance(T value) {
+    _mode = Mode.INSTANCE;
+    _instance = value;
+    _isSingeltone = true;
+    return this;
+  }
+
+  /// RU: Инициализация экземляпяра  через провайдер [value].
+  /// ENG: Initialization instance via provider [value].
+  ///
+  /// return [Binding]
+  Binding<T> toProvide(T Function() value) {
+    _mode = Mode.PROVIDER_INSTANCE;
+    _provider = value;
+    return this;
+  }
+
+  /// RU: Инициализация экземляпяра  как сингелтон [value].
+  /// ENG: Initialization instance as a singelton [value].
+  ///
+  /// return [Binding]
+  Binding<T> singeltone() {
+    _isSingeltone = true;
+    return this;
+  }
+
+  /// RU: Поиск экземпляра.
+  /// ENG: Resolve instance.
+  ///
+  /// return [T]
+  T? get instance => _instance;
+
+  /// RU: Поиск экземпляра.
+  /// ENG: Resolve instance.
+  ///
+  /// return [T]
+  T? get provider {
+    if (_isSingeltone) {
+      _instance ??= _provider?.call();
+      return _instance;
+    }
+    return _provider?.call();
+  }
+}