存档重构，游戏内容解锁机制；教程完善（未完成）

Assets/Scripts/Menu/ChapterSelection/ChapterSelectionUnit.cs

@@ -21,6 +21,14 @@ namespace Ichni.Menu
         public Sprite avatar;
         public Switch chapterSwitch;
 
+        /// <summary>
+        /// 章节剧情入口与选曲入口共用的内容解锁规则。
+        /// 留空表示章节从新档开始即可访问；需要锁定时请使用 <see cref="UnlockRequirement"/>，
+        /// 并遵守 <see cref="UnlockSaveModule.KeyNamingRule"/> 中的下划线 Key 规则。
+        /// </summary>
+        [LabelText("Unlock Requirement")]
+        public UnlockRequirement unlockRequirement = new UnlockRequirement();
+
         [Searchable]
         public List<SongItemData> songs = new List<SongItemData>();
 
@@ -54,11 +62,6 @@ namespace Ichni.Menu
 
     public partial class ChapterSelectionUnit
     {
-        public List<string> GetRelatedSongNamesOfUnlockKey(string key)
-        {
-            return (from song in songs where song.storyUnlockKey == key select song.songName).ToList();
-        }
-
         public (int, int, int, int, int) GetChapterSaveInfo()
         {
             int beatmapCount = 0;
@@ -72,9 +75,19 @@ namespace Ichni.Menu
                 if (GameSaveManager.instance.SongSaveModule.songStatusSaves.TryGetValue(song.songName, out var songStatus))
                 {
                     bool thisSongFinished = false;
-                    foreach (BeatmapSave beatmapSave in songStatus.beatmapSaves)
+                    foreach (DifficultyData difficulty in song.difficultyDataList)
                     {
+                        if (difficulty == null || difficulty.saveDifficultyId < 0)
+                        {
+                            continue;
+                        }
+
                         beatmapCount++;
+                        if (!songStatus.TryGetBeatmapSave(difficulty.saveDifficultyId, out BeatmapSave beatmapSave))
+                        {
+                            continue;
+                        }
+
                         if (!beatmapSave.IsEmpty())
                         {
                             thisSongFinished = true;
@@ -131,17 +144,24 @@ namespace Ichni.Menu
         [FoldoutGroup("$songName")]
         public List<DifficultyData> difficultyDataList;
 
+        /// <summary>
+        /// 歌曲自身的内容解锁规则。章节是否开放由 <see cref="ChapterSelectionUnit.unlockRequirement"/> 单独判断；
+        /// 真正进入歌曲时两者必须同时满足。
+        /// </summary>
         [FoldoutGroup("$songName")]
-        public string storyUnlockKey;
-
-        [FoldoutGroup("$songName")]
-        public string paymentUnlockKey;
+        [LabelText("Unlock Requirement")]
+        public UnlockRequirement unlockRequirement = new UnlockRequirement();
     }
 
     [Serializable]
     public class DifficultyData
     {
-        public int difficultyIndex;
+        /// <summary>
+        /// 歌曲成绩的稳定 ID，不等同于选曲 UI 的难度列表位置。
+        /// 发布后不要更改或复用既有 ID；新增难度必须使用从未分配过的非负 ID。
+        /// </summary>
+        [FormerlySerializedAs("difficultyIndex")]
+        public int saveDifficultyId;
         public string difficultyName;
         public string displayDifficultyName;
         public int difficultyValue;
@@ -149,14 +169,19 @@ namespace Ichni.Menu
         public Color color;
         public bool isAvailable;
         public bool ForceFullScreenJudge = false;
+
+        [MinValue(1)]
+        [Tooltip("仅当 Note、Timing 或判定规则变化，导致成绩不可与旧谱面比较时递增；UI、文本、封面和音量调整不递增。")]
+        public int chartRevision = 1;
+
         public DifficultyData()
         {
 
         }
 
-        public DifficultyData(int difficultyIndex, string difficultyName, string displayDifficultyName, int difficultyValue, string charterName, Color color, bool ForceFullScreenJudge = false)
+        public DifficultyData(int saveDifficultyId, string difficultyName, string displayDifficultyName, int difficultyValue, string charterName, Color color, bool ForceFullScreenJudge = false)
         {
-            this.difficultyIndex = difficultyIndex;
+            this.saveDifficultyId = saveDifficultyId;
             this.difficultyName = difficultyName;
             this.displayDifficultyName = displayDifficultyName;
             this.charterName = charterName;
@@ -170,5 +195,13 @@ namespace Ichni.Menu
         {
             return string.IsNullOrEmpty(displayDifficultyName) ? difficultyName : displayDifficultyName;
         }
+
+        /// <summary>
+        /// 返回合法的 Revision。配置侧始终至少使用 1；0 只会被视为未初始化值并被钳制。
+        /// </summary>
+        public int GetChartRevision()
+        {
+            return Mathf.Max(1, chartRevision);
+        }
     }
 }