export class Result<T, E = Error> {
  private constructor(
    private readonly _isSuccess: boolean,
    private readonly _value?: T,
    private readonly _error?: E
  ) {}

  public static ok<U>(value: U): Result<U, never> {
    return new Result<U, never>(true, value);
  }

  public static fail<F>(error: F): Result<never, F> {
    return new Result<never, F>(false, undefined, error);
  }

  public get isSuccess(): boolean {
    return this._isSuccess;
  }

  public get isFailure(): boolean {
    return !this._isSuccess;
  }

  public getValue(): T {
    if (!this._isSuccess) {
      throw new Error(`Cannot get value from failed Result: ${this._error}`);
    }
    return this._value as T;
  }

  public getError(): E {
    if (this._isSuccess) {
      throw new Error("Cannot get error from successful Result");
    }
    return this._error as E;
  }
}