import { Container } from "inversify";
import { inversifyContainer } from "../inversify.config";

export class TestEnvironment {
  private _container: Container;

  /**
   * Constructs a new testing environment
   *
   * @param config - optional, can set classes to bind and classes to mock for the test environment
   */
  constructor(config?: {
    classesToBind?: any[];
    classesToMock?: { real: any; mock: any }[];
  }) {
    this._container = inversifyContainer.createChild();
    if (config) {
      if (config.classesToBind) {
        this.bind(config.classesToBind);
      }

      if (config.classesToMock) {
        this.mockClass(config.classesToMock);
      }
    }
  }

  /**
   * binds a class to the test environment
   *
   * @param classes - the classes to bind to the test environment
   *
   */
  public bind(classes: any[]) {
    classes.forEach(c => this._container.bind(c).toSelf());
  }

  /**
   * inserts a mocked class instead of the real class
   *
   * @param mocks - a list of real classes with their mocked class
   */
  public mockClass(mocks: { real: any; mock?: any; mockedClass?: any }[]) {
    mocks.forEach(m => {
      if (m.mock) {
        this._container.bind(m.real).toConstantValue(m.mock);
      } else if (m.mockedClass) {
        this._container.bind(m.real).to(m.mockedClass);
      }
    });
  }

  public get<T>(className: any) {
    return this._container.get<T>(className);
  }

  public clear() {
    this._container = inversifyContainer.createChild();
  }
}