[F&R] 1. 现在的ugcgenerator缺少SflEvent的生成/写出。

    2. 现在的ugcparser，@SPDMOD的解析是错的。
    3. 抽取TryParseUgcMeasureTick方法

Author: Starrah

chart/chu/ChuNote.cs

@@ -15,7 +15,7 @@ public class ChuNote: BaseNote
     /** 宽度 (1–16) */
     public int Width { get; set; } = 1;
     /** HLD/SLD/AHD/ASD等的 持续时长 */
-    public Rational Duration { get; set; } = 0;
+    public Rational Duration { get; set => field = value.CanonicalForm; } = 0;
     /** SLD 终点列 */
     public int EndCell { get; set; }
     /** SLD 终点宽度 */
@@ -27,5 +27,5 @@ public class ChuNote: BaseNote
     /** ASD/ASC/ALD上具有的、目前含义还不明确的字段，统一收集到这个里面。 */
     public List<int> ExtraData = [];
 
-    public override Rational EndTime => Time + Duration;
+    public override Rational EndTime => (Time + Duration).CanonicalForm;
 }

generator/chu/C2sGenerator.cs

@@ -33,6 +33,7 @@ private static C2sChart ConvertToC2s(IChuChart chart, List<Alert> alerts)
             };
             result.BpmList.AddRange(ugc.BpmList);
             result.MetList.AddRange(ugc.MetList);
+            result.SflList.AddRange(ugc.SflList);
             result.Notes = ugc.Notes;
             return result;
         }

generator/chu/UgcGenerator.cs

@@ -36,6 +36,7 @@ private static UgcChart ConvertToUgc(IChuChart chart, List<Alert> alerts)
             };
             result.BpmList.AddRange(c2s.BpmList);
             result.MetList.AddRange(c2s.MetList);
+            result.SflList.AddRange(c2s.SflList);
             result.Notes = c2s.Notes;
             return result;
         }
@@ -70,6 +71,13 @@ private static string Serialize(UgcChart ugc)
             sb.AppendLine($"@BPM\t{m}'{o}\t{b.Bpm:F5}");
         }
         sb.AppendLine("@TIL\t0\t0'0\t1.00000");
+
+        foreach (var s in ugc.SflList.OrderBy(x => x.Time)) 
+        { 
+            var (m, o) = Utils.BarAndTick(s.Time, tpm); 
+            sb.AppendLine($"@SPDMOD\t{m}'{o}\t{s.Multiplier:0.00000}");
+        }
+
         sb.AppendLine("@MAINTIL\t0");
         sb.AppendLine("@ENDHEAD");
         sb.AppendLine();

parser/chu/UgcParser.cs

@@ -61,9 +61,26 @@ public class UgcParser : IParser<UgcChart>
             }
         }
 
+        FinalizeUgcSflDurations(chart);
         return (chart, alerts);
     }
 
+    private static void FinalizeUgcSflDurations(UgcChart chart)
+    {
+        if (chart.SflList.Count == 0) return;
+        chart.SflList = chart.SflList.OrderBy(s => s.Time).ToList();
+        var endTime = Utils.Max(chart.SflList[^1].Time, chart.Notes.Max(x=>x.EndTime));
+        
+        for (var i = 0; i < chart.SflList.Count; i++)
+        {
+            var t = chart.SflList[i].Time;
+            var dur = (i < chart.SflList.Count - 1 ? chart.SflList[i+1].Time : endTime) - t;
+            chart.SflList[i] = chart.SflList[i] with { Duration = dur.CanonicalForm };
+        }
+
+        chart.SflList = chart.SflList.Where(x => x.Multiplier != 1).ToList(); // 倍率为1的，没必要放进来的
+    }
+
     private static void ParseHeaderLine(string line, UgcChart chart, List<Alert> alerts, int lineNum)
     {
         if (!line.StartsWith('@'))
@@ -154,10 +171,7 @@ private static void ParseHeaderLine(string line, UgcChart chart, List<Alert> ale
                 {
                     var measureOffset = bpmPart[..bpmSpaceIdx];
                     var bpmValueStr = bpmPart[(bpmSpaceIdx + 1)..];
-                    var apostropheIdx = measureOffset.IndexOf('\'');
-                    if (apostropheIdx > 0
-                        && int.TryParse(measureOffset[..apostropheIdx], NumberStyles.Integer, CultureInfo.InvariantCulture, out var bpmMeasure)
-                        && int.TryParse(measureOffset[(apostropheIdx + 1)..], NumberStyles.Integer, CultureInfo.InvariantCulture, out var bpmOffset)
+                    if (TryParseUgcMeasureTick(measureOffset, out var bpmMeasure, out var bpmOffset)
                         && decimal.TryParse(bpmValueStr, NumberStyles.Float, CultureInfo.InvariantCulture, out var bpmValue))
                     {
                         var tpm = chart.TicksPerBeat * 4;
@@ -182,20 +196,40 @@ private static void ParseHeaderLine(string line, UgcChart chart, List<Alert> ale
                 break;
 
             case "@SPDMOD":
+            {
+                var parts = value.Split('\t', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+                if (parts.Length >= 2
+                    && TryParseUgcMeasureTick(parts[0], out var meas, out var tick)
+                    && decimal.TryParse(parts[1], NumberStyles.Float, CultureInfo.InvariantCulture, out var mult))
                 {
-                    var parts = value.Split(['\t', ' '], StringSplitOptions.RemoveEmptyEntries);
-                    if (parts.Length >= 2 && int.TryParse(parts[0], NumberStyles.Integer, CultureInfo.InvariantCulture, out var tilMeasure)
-                        && double.TryParse(parts[1], NumberStyles.Float, CultureInfo.InvariantCulture, out var tilMult))
-                        chart.SflList.Add((tilMeasure, Rational.Zero, (decimal)tilMult));
+                    var tpm = chart.TicksPerBeat * 4;
+                    chart.SflList.Add((meas + new Rational(tick, tpm), Rational.Zero, mult));
                 }
+                else
+                    alerts.Add(new Alert(Warning, $"@SPDMOD 格式错误: {line}") { Line = lineNum });
                 break;
+            }
 
             default:
                 alerts.Add(new Alert(Info, $"未知头部标签: {tag}") { Line = lineNum });
                 break;
         }
     }
 
+    /** UGC 时刻字符串 measure'tick（@BPM、@SPDMOD、音符行 #m't 共用）。 */
+    private static bool TryParseUgcMeasureTick(string measureTick, out int measure, out int tick)
+    {
+        measure = 0;
+        tick = 0;
+        measureTick = measureTick.Trim();
+        var ap = measureTick.IndexOf('\'');
+        if (ap <= 0)
+            return false;
+
+        return int.TryParse(measureTick[..ap], NumberStyles.Integer, CultureInfo.InvariantCulture, out measure)
+            && int.TryParse(measureTick[(ap + 1)..], NumberStyles.Integer, CultureInfo.InvariantCulture, out tick);
+    }
+
     private static int ParseNoteLine(string[] lines, int idx, UgcChart chart, List<Alert> alerts)
     {
         var line = lines[idx];
@@ -219,21 +253,15 @@ private static int ParseNoteLine(string[] lines, int idx, UgcChart chart, List<A
         var prefix = line[..colonIdx];
         var code = line[(colonIdx + 1)..];
         var hashIdx = prefix.IndexOf('#');
-        var apostropheIdx = prefix.IndexOf('\'');
-        if (hashIdx < 0 || apostropheIdx < 0 || apostropheIdx <= hashIdx + 1)
+        if (hashIdx < 0)
         {
             alerts.Add(new Alert(Warning, $"音符行前缀格式错误: {line}") { Line = lineNum });
             return idx;
         }
 
-        if (!int.TryParse(prefix[(hashIdx + 1)..apostropheIdx], NumberStyles.Integer, CultureInfo.InvariantCulture, out var measure))
-        {
-            alerts.Add(new Alert(Warning, $"无法解析 measure: {line}") { Line = lineNum });
-            return idx;
-        }
-        if (!int.TryParse(prefix[(apostropheIdx + 1)..], NumberStyles.Integer, CultureInfo.InvariantCulture, out var tick))
+        if (!TryParseUgcMeasureTick(prefix[(hashIdx + 1)..], out var measure, out var tick))
         {
-            alerts.Add(new Alert(Warning, $"无法解析 tick: {line}") { Line = lineNum });
+            alerts.Add(new Alert(Warning, $"无法解析 measure'tick: {line}") { Line = lineNum });
             return idx;
         }
 

utils/Utils.cs

@@ -28,6 +28,8 @@ internal static Exception Fail(string msg = "")
 
     public static BigInteger Max(BigInteger a, BigInteger b) => a > b ? a : b;
 
+    public static Rational Max(Rational a, Rational b) => a > b ? a : b;
+    
     public static Rational Min(Rational a, Rational b) => a < b ? a : b;
 
     private static readonly Dictionary<string, int> _simaiLexerMap = Enumerable.Range(1, L.ruleNames.Length)