/// <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);
ThrowIfDegreeIsOutOfRange(scale, degree);
return(scale.GetStep((int)degree));
}
internal static ParsingResult TryParse(string input, Scale scale, out ChordProgression chordProgression)
{
chordProgression = null;
if (string.IsNullOrWhiteSpace(input))
{
return(ParsingResult.EmptyInputString);
}
var matches = ParsingUtilities.Matches(input, Patterns, ignoreCase: false);
if (matches == null)
{
return(ParsingResult.NotMatched);
}
var chords = new List <Chord>();
foreach (var match in matches)
{
var degreeGroup = match.Groups[ScaleDegreeGroupName];
var degreeRoman = degreeGroup.Value.ToLower();
if (string.IsNullOrWhiteSpace(degreeRoman))
{
continue;
}
var degree = RomanToInteger(degreeRoman);
var rootNoteName = scale.GetStep(degree - 1);
var fullString = match.Value;
var matchIndex = match.Index;
var degreeGroupIndex = degreeGroup.Index;
var chordString =
fullString.Substring(0, degreeGroupIndex - matchIndex) +
rootNoteName +
fullString.Substring(degreeGroupIndex - matchIndex + degreeGroup.Length);
Chord chord;
var chordParsingResult = ChordParser.TryParse(chordString, out chord);
if (chordParsingResult.Status != ParsingStatus.Parsed)
{
return(chordParsingResult);
}
chords.Add(chord);
}
chordProgression = new ChordProgression(chords);
return(ParsingResult.Parsed);
}