/// <summary>
/// Adds the <em>external</em> indication to the left side of the <paramref name="arrow"/>.
/// </summary>
/// <returns>The arrow with the external indication on the left side.</returns>
public static Arrow ExternalLeft(this Arrow arrow)
{
if (arrow.IsExternalLeft())
{
return(arrow);
}
return(new Arrow(ArrowParts.LeftExternal + arrow.LeftHead, arrow.Dotted, arrow.RightHead, arrow.Color));
}
/// <summary>
/// Renders a sequence arrow.
/// </summary>
/// <param name="left">The left side of the arrow.</param>
/// <param name="arrow">The arrow configuration.</param>
/// <param name="right">The right side of the arrow.</param>
/// <param name="message">Optional message for the arrow.</param>
/// <param name="lifeEvents">Optional changes to the life of the <em>source</em> or <em>target</em>.</param>
/// <param name="activationColor">Optional color for the target activation.</param>
/// <exception cref="ArgumentNullException"><paramref name="stringBuilder"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException"><paramref name="arrow"/> is <c>null</c>, empty of only white space.</exception>
/// <exception cref="ArgumentException"><paramref name="left"/> or <paramref name="right"/> is empty of only white space.</exception>
/// <exception cref="ArgumentException"><paramref name="arrow"/> consists of less then 2 characters.</exception>
/// <exception cref="NotSupportedException"><paramref name="left"/> and <paramref name="right"/> are both <c>null</c>, or the arrow has an external symbol on the other side of the undefined participant.</exception>
public static void Arrow(this StringBuilder stringBuilder, ParticipantName left, Arrow arrow, ParticipantName right, string message = default, LifeLineEvents lifeEvents = default, Color activationColor = default)
{
if (stringBuilder is null)
{
throw new ArgumentNullException(nameof(stringBuilder));
}
if (arrow is null)
{
throw new ArgumentException("A non-empty value should be provided", nameof(arrow));
}
if (left is null && right is null)
{
throw new NotSupportedException("It is not possible for both partipants to be outside the diagram.");
}
if (left is null && arrow.IsExternalRight())
{
throw new NotSupportedException("It is not possible for both partipants to be outside the diagram.");
}
if (right is null && arrow.IsExternalLeft())
{
throw new NotSupportedException("It is not possible for both partipants to be outside the diagram.");
}
if (left is null)
{
stringBuilder.Append(arrow.ExternalLeft());
}
else
{
stringBuilder.Append(left);
}
stringBuilder.Append(Constant.Space);
if (left is not null && right is not null)
{
stringBuilder.Append(arrow);
stringBuilder.Append(Constant.Space);
}
if (right is null)
{
stringBuilder.Append(arrow.ExternalRight());
}
else
{
stringBuilder.Append(right);
}
if (lifeEvents is not null && lifeEvents != LifeLineEvents.None)
{
stringBuilder.Append(Constant.Space);
stringBuilder.Append(lifeEvents);
}
if (activationColor is not null)
{
stringBuilder.Append(Constant.Space);
stringBuilder.Append(activationColor);
}
if (!string.IsNullOrEmpty(message))
{
stringBuilder.Append(Constant.Space);
stringBuilder.Append(Constant.Colon);
stringBuilder.Append(Constant.Space);
stringBuilder.Append(message.Replace("\n", "\\n"));
}
stringBuilder.AppendNewLine();
}