| 1 | using Eto.Parse; |
| 2 | |
| 3 | namespace CascadeIDE.Services.ChordNotation; |
| 4 | |
| 5 | /// <summary> |
| 6 | /// Разбор нотации из <c>docs/chord-notation-cascadeide.md</c> (EBNF там же). |
| 7 | /// Грамматика задаётся через <see cref="Eto.Parse"/> (fluent API, один-в-один с EBNF). |
| 8 | /// </summary> |
| 9 | public static class ChordNotationParser |
| 10 | { |
| 11 | /// <summary>Парсит строку (например <c><C-k> s p</c>). Пустая строка — успех с нулём шагов.</summary> |
| 12 | public static ChordNotationParseResult Parse(string? input) |
| 13 | { |
| 14 | if (string.IsNullOrEmpty(input)) |
| 15 | return ChordNotationParseResult.Ok(Array.Empty<ChordNotationStep>()); |
| 16 | |
| 17 | var trimmed = input.Trim(); |
| 18 | var gm = ChordNotationGrammar.Instance.Match(trimmed); |
| 19 | if (!gm.Success) |
| 20 | return ChordNotationParseResult.Fail(FormatGrammarError(gm, trimmed)); |
| 21 | |
| 22 | var tokens = trimmed.Split((char[]?)null, StringSplitOptions.RemoveEmptyEntries); |
| 23 | var steps = new List<ChordNotationStep>(tokens.Length); |
| 24 | foreach (var t in tokens) |
| 25 | { |
| 26 | if (t.Length >= 2 && t[0] == '<' && t[^1] == '>') |
| 27 | { |
| 28 | steps.Add(ParseBracketInner(t.AsSpan(1, t.Length - 2))); |
| 29 | continue; |
| 30 | } |
| 31 | |
| 32 | steps.Add(new ChordNotationPlainStep(t)); |
| 33 | } |
| 34 | |
| 35 | return ChordNotationParseResult.Ok(steps); |
| 36 | } |
| 37 | |
| 38 | /// <summary>Vim-стиль (<c><C-k> s p</c>) → нормализованная модель (см. два слоя в доке).</summary> |
| 39 | public static bool TryParseVimToNormalized(string? input, out NormalizedKeySequence? sequence, out string error) |
| 40 | { |
| 41 | sequence = null; |
| 42 | var r = Parse(input); |
| 43 | if (!r.IsSuccess) |
| 44 | { |
| 45 | error = r.Error; |
| 46 | return false; |
| 47 | } |
| 48 | |
| 49 | sequence = ChordSemanticNormalizer.FromVimSteps(r.Steps); |
| 50 | error = ""; |
| 51 | return true; |
| 52 | } |
| 53 | |
| 54 | private static ChordNotationChordStep ParseBracketInner(ReadOnlySpan<char> inner) |
| 55 | { |
| 56 | var mods = new List<string>(4); |
| 57 | while (!inner.IsEmpty) |
| 58 | { |
| 59 | if (inner.StartsWith("Alt-", StringComparison.Ordinal)) |
| 60 | { |
| 61 | mods.Add("Alt-"); |
| 62 | inner = inner[4..]; |
| 63 | continue; |
| 64 | } |
| 65 | |
| 66 | if (inner.StartsWith("C-", StringComparison.Ordinal)) |
| 67 | { |
| 68 | mods.Add("C-"); |
| 69 | inner = inner[2..]; |
| 70 | continue; |
| 71 | } |
| 72 | |
| 73 | if (inner.StartsWith("M-", StringComparison.Ordinal)) |
| 74 | { |
| 75 | mods.Add("M-"); |
| 76 | inner = inner[2..]; |
| 77 | continue; |
| 78 | } |
| 79 | |
| 80 | if (inner.StartsWith("A-", StringComparison.Ordinal)) |
| 81 | { |
| 82 | mods.Add("A-"); |
| 83 | inner = inner[2..]; |
| 84 | continue; |
| 85 | } |
| 86 | |
| 87 | if (inner.StartsWith("S-", StringComparison.Ordinal)) |
| 88 | { |
| 89 | mods.Add("S-"); |
| 90 | inner = inner[2..]; |
| 91 | continue; |
| 92 | } |
| 93 | |
| 94 | if (inner.StartsWith("D-", StringComparison.Ordinal)) |
| 95 | { |
| 96 | mods.Add("D-"); |
| 97 | inner = inner[2..]; |
| 98 | continue; |
| 99 | } |
| 100 | |
| 101 | break; |
| 102 | } |
| 103 | |
| 104 | var key = inner.ToString(); |
| 105 | if (key.Length == 0) |
| 106 | throw new InvalidOperationException("Chord notation: пустой key внутри <…> (грамматика должна была отсечь)."); |
| 107 | |
| 108 | return new ChordNotationChordStep(mods, key); |
| 109 | } |
| 110 | |
| 111 | private static string FormatGrammarError(GrammarMatch gm, string text) |
| 112 | { |
| 113 | var idx = gm.ErrorIndex >= 0 ? gm.ErrorIndex : 0; |
| 114 | var tail = idx < text.Length ? text[idx..] : ""; |
| 115 | tail = tail.Length > 24 ? tail[..24] + "…" : tail; |
| 116 | return $"Chord notation: разбор остановился на позиции {idx} (остаток: «{tail}»)."; |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | /// <param name="IsSuccess">Успех полного разбора.</param> |
| 121 | /// <param name="Steps">Шаги последовательности (после успеха).</param> |
| 122 | /// <param name="Error">Сообщение при неуспехе.</param> |
| 123 | public readonly record struct ChordNotationParseResult(bool IsSuccess, IReadOnlyList<ChordNotationStep> Steps, string Error) |
| 124 | { |
| 125 | public static ChordNotationParseResult Ok(IReadOnlyList<ChordNotationStep> steps) => |
| 126 | new(true, steps, ""); |
| 127 | |
| 128 | public static ChordNotationParseResult Fail(string message) => |
| 129 | new(false, Array.Empty<ChordNotationStep>(), message); |
| 130 | } |
| 131 | |
| 132 | public abstract record ChordNotationStep; |
| 133 | |
| 134 | /// <summary>Совпадающее нажатие: <c><C-k></c>, <c><C-M-n></c>.</summary> |
| 135 | public sealed record ChordNotationChordStep(IReadOnlyList<string> ModifierPrefixes, string Key) : ChordNotationStep; |
| 136 | |
| 137 | /// <summary>Токен без скобок: <c>m</c>, <c>Esc</c>, <c>L1</c>.</summary> |
| 138 | public sealed record ChordNotationPlainStep(string Token) : ChordNotationStep; |
| 139 | |