/// <summary>
/// Checks if the specified note belongs to a scale or not.
/// </summary>
/// <param name="scale"><see cref="Scale"/> to check the note.</param>
/// <param name="note"><see cref="Note"/> to check if it belongs to the <paramref name="scale"/>
/// or not.</param>
/// <returns>true if <paramref name="note"/> belongs to the <paramref name="scale"/>;
/// otherwise, false.</returns>
/// <exception cref="ArgumentNullException"><paramref name="scale"/> is null. -or-
/// <paramref name="note"/> is null.</exception>
public static bool IsNoteInScale(this Scale scale, Note note)
{
ThrowIfArgument.IsNull(nameof(scale), scale);
ThrowIfArgument.IsNull(nameof(note), note);
return(scale.GetNotes()
.Contains(note));
}
/// <summary>
/// Gets notes that belong to a musical scale in ascending order starting with the specified
/// root note.
/// </summary>
/// <param name="scale"><see cref="Scale"/> to get notes of.</param>
/// <param name="rootNote"><see cref="Note"/> to start a sequence of scale's notes with.</param>
/// <returns>Notes that belong to the <paramref name="scale"/> in ascending order starting with
/// the <paramref name="rootNote"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="scale"/> is null. -or-
/// <paramref name="rootNote"/> is null.</exception>
public static IEnumerable <Note> GetAscendingNotes(this Scale scale, Note rootNote)
{
ThrowIfArgument.IsNull(nameof(scale), scale);
ThrowIfArgument.IsNull(nameof(rootNote), rootNote);
return(scale.GetNotes()
.SkipWhile(n => n != rootNote));
}
/// <summary>
/// Gets notes that belong to a musical scale in descending order starting with the specified
/// root note.
/// </summary>
/// <param name="scale"><see cref="Scale"/> to get notes of.</param>
/// <param name="rootNote"><see cref="Note"/> to start a sequence of scale's notes with.</param>
/// <returns>Notes that belong to the <paramref name="scale"/> in descending order starting with
/// the <paramref name="rootNote"/>.</returns>
/// <exception cref="ArgumentNullException"><paramref name="scale"/> is null. -or-
/// <paramref name="rootNote"/> is null.</exception>
public static IEnumerable <Note> GetDescendingNotes(this Scale scale, Note rootNote)
{
ThrowIfArgument.IsNull(nameof(scale), scale);
ThrowIfArgument.IsNull(nameof(rootNote), rootNote);
return(new[] { rootNote }.Concat(scale.GetNotes()
.TakeWhile(n => n != rootNote)
.Reverse()));
}
/// <summary>
/// Gets <see cref="NoteName"/> corresponding to the specified degree of a musical scale.
/// </summary>
/// <param name="scale"><see cref="Scale"/> to get degree of.</param>
/// <param name="degree"><see cref="ScaleDegree"/> representing a degree of the
/// <paramref name="scale"/>.</param>
/// <returns>The degree of the scale.</returns>
/// <exception cref="ArgumentNullException"><paramref name="scale"/> is null.</exception>
/// <exception cref="InvalidEnumArgumentException"><paramref name="degree"/> specified an
/// invalid value.</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="degree"/> is out of
/// range for the <paramref name="scale"/>.</exception>
public static NoteName GetDegree(this Scale scale, ScaleDegree degree)
{
ThrowIfArgument.IsNull(nameof(scale), scale);
ThrowIfArgument.IsInvalidEnumValue(nameof(degree), degree);
var degreeNumber = (int)degree;
if (degreeNumber >= scale.Intervals.Count())
{
throw new ArgumentOutOfRangeException(nameof(degree),
degree,
"Degree is out of range for the scale.");
}
return(scale.GetNotes()
.Skip(degreeNumber)
.First()
.NoteName);
}
