/**
 * A comment about what story points are.
 */
@PropertyIntValueRange(
  value = { 0, 1, 2, 3, 5, 8, 13, 21, 50, 100 },
  defaultValue = 8)
Integer storyPoint();

/**
 * A comment on the states as a whole.
 */
@PropertyStringValueRange(
  value = { "cold", "normal", "hot" },
  defaultValue = "normal")
String temperature();

/**
 * The valid priority values for user stories.
 */
public enum Priority
{
  // ****************************** Enumeration *******************************

  /**
   * The story is required for the final product.
   */
  REQUIRED("required", 1),

  /**
   * The story is very important for the final product.
   */
  VERY_IMPORTANT("very-important", 2),

  /**
   * The story is a nice-to-have for the final product, but not relevant for the
   * release.
   */
  NICE_TO_HAVE("nice-to-have", 3),

  /**
   * The story would add to the user experience of the user, but is not relevant
   * for the release.
   */
  POLISHING("polishing", 4),

  /**
   * The story is not necessary to be part of the release, but may be included
   * if resources are available. If the product backlog contains only
   * dispensable stores, the development is likely to come to an end.
   * <p>
   * The priority is available to keep stories in the product backlog for
   * further references.
   * </p>
   */
  DISPENSABLE("dispensable", 5);

  // ********************************* Fields *********************************

  // --- constants ------------------------------------------------------------

  // --- members --------------------------------------------------------------

  /**
   * The identifier of the priority. This value is used for resource lookups.
   */
  private final String id;

  /**
   * The value of the priority.
   */
  private final int priorityValue;

  // ****************************** Constructors ******************************

  /**
   * Default constructor.
   *
   * @param id the identifier of the priority.
   * @param priorityValue the value of the priority.
   * @see
   */
  private Priority(final String id, final int priorityValue)
  {
    this.id = id;
    this.priorityValue = priorityValue;
  }

  // ********************************* Methods ********************************

  // --- init -----------------------------------------------------------------

  // --- get&set --------------------------------------------------------------

  /**
   * Returns the identifier of the priority. This value is used for resource
   * lookups.
   *
   * @return the identifier of the priority.
   */
  public String getId()
  {
    return id;
  }

  /**
   * Returns the value of the priority.
   *
   * @return the value of the priority.
   */
  public int getPriorityValue()
  {
    return priorityValue;
  }

  public boolean isCommented()
  {
    return true;
  }

  // --- business -------------------------------------------------------------

  public List<Priority> getValues()
  {
    return Arrays.asList(values());
  }

  public static Priority fromString(final String valueAsString)
    throws IllegalArgumentException
  {
    for (Priority priority : values())
    {
      if (valueAsString.equals(priority.id))
      {
        return priority;
      }
    }

    final String message =
        "The value '" + valueAsString
            + "' is not a valid value for priority. Valid values are: "
            + toString(Locale.ENGLISH);
    throw new IllegalArgumentException(message);
  }

  public static String toString(final Locale locale)
  {
    final StringBuilder buffer = new StringBuilder(64);
    for (Priority priority : values())
    {
      buffer.append(priority.id).append(", ");
    }

    final int length = buffer.length();
    if (length > 0)
    {
      buffer.setLength(length - 2);
    }

    return buffer.toString();
  }

  // --- object basics --------------------------------------------------------

  @Override
  public String toString()
  {
    return id;
  }
}

@PropertyExpression("required")
Priority priority();