testlevel chapters 2-31 overwrite game memory (coin counter and flag rows end after world 8: progress, language, options): level projects, play-tests and the arena use chapters 1 and 32-49, old settings migrate; level tally counts the level's own coins and secrets

src/main/java/com/eliasmueller/llamamod/editor/tools/environment/LevelSettingsDialog.java

@@ -17,6 +17,7 @@ import com.eliasmueller.llamamod.editor.model.cmd.Command;
 import com.eliasmueller.llamamod.editor.model.cmd.SetProp;
 import com.eliasmueller.llamamod.editor.ui.EditorContext;
 import com.eliasmueller.llamamod.mods.levels.LevelProjects;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.awt.BorderLayout;
 import java.awt.Dimension;
 import java.awt.GridLayout;
@@ -38,6 +39,7 @@ import javax.swing.JScrollPane;
 import javax.swing.JSpinner;
 import javax.swing.JTextArea;
 import javax.swing.JTextField;
+import javax.swing.SpinnerListModel;
 
 /** Level → Settings: name, chapter, grid size, death plane, WFPC flags, object pool (one undo step). */
 final class LevelSettingsDialog {
@@ -80,9 +82,13 @@ final class LevelSettingsDialog {
                 "Base level",
                 new JLabel(st.base() + "  (object code, textures, sounds)"),
                 "Fixed when the project is created (the project stores only the differences to it)");
-        JSpinner chapter = Ui.number(Math.max(1, st.targetChapter()), 1, 49, 1, "0", v -> {});
+        JSpinner chapter = new JSpinner(new SpinnerListModel(TestLevelChapters.all()));
+        chapter.setValue(TestLevelChapters.migrate(st.targetChapter()));
         JLabel used = new JLabel(usedChapters(ctx, st.targetChapter()));
-        f.row("TestLevel chapter", chapter, "New levels replace this chapter of world 9 (TestLevel)");
+        f.row(
+                "TestLevel chapter",
+                chapter,
+                "New levels replace this chapter of world 9 (TestLevel): 32–49, or 1 (the Test World's)");
         f.full(used);
         chapter.setEnabled(st.isNewLevel());
 

src/main/java/com/eliasmueller/llamamod/editor/tools/playtest/PlaytestRunner.java

@@ -17,6 +17,7 @@ import com.eliasmueller.llamamod.platform.Config;
 import com.eliasmueller.llamamod.platform.GameLauncher;
 import com.eliasmueller.llamamod.platform.Json;
 import com.eliasmueller.llamamod.platform.Progress;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import com.eliasmueller.llamamod.save.Worlds;
 import java.io.IOException;
 import java.nio.file.Files;
@@ -50,7 +51,7 @@ public final class PlaytestRunner {
     /** World/chapter of a project: TestLevel chapter, or the original's place; null if not on the map. */
     public static int[] target(Document d) {
         if (d.isNewLevel()) {
-            return new int[] {9, Math.max(1, d.scene().settings().targetChapter())};
+            return new int[] {9, TestLevelChapters.migrate(d.scene().settings().targetChapter())};
         }
         Matcher m = Pattern.compile("t1l(\\d)m(\\d{3})").matcher(d.base().toLowerCase(Locale.ROOT));
         if (m.matches()) {

src/main/java/com/eliasmueller/llamamod/editor/ui/NewLevelDialog.java

@@ -4,6 +4,7 @@ import com.eliasmueller.llamamod.editor.io.ProjectIO;
 import com.eliasmueller.llamamod.editor.io.ProjectInfo;
 import com.eliasmueller.llamamod.editor.io.Templates;
 import com.eliasmueller.llamamod.mods.levels.LevelProjects;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.awt.BorderLayout;
 import java.awt.Component;
 import java.awt.Dimension;
@@ -28,7 +29,7 @@ import javax.swing.JPanel;
 import javax.swing.JRadioButton;
 import javax.swing.JSpinner;
 import javax.swing.JTextField;
-import javax.swing.SpinnerNumberModel;
+import javax.swing.SpinnerListModel;
 import javax.swing.UIManager;
 
 /** New level: name, base level (object types, textures, sky, music), template, TestLevel chapter. */
@@ -51,7 +52,8 @@ final class NewLevelDialog extends JDialog {
                 base.setSelectedItem(l);
             }
         }
-        JSpinner chapter = new JSpinner(new SpinnerNumberModel(nextFreeChapter(w), 1, 49, 1));
+        JSpinner chapter = new JSpinner(new SpinnerListModel(TestLevelChapters.all()));
+        chapter.setValue(nextFreeChapter(w));
         PicturePanel pic = new PicturePanel(300, 170);
         Runnable updatePic = () -> {
             OriginalLevels.Level l = (OriginalLevels.Level) base.getSelectedItem();
@@ -75,7 +77,8 @@ final class NewLevelDialog extends JDialog {
                 row,
                 "TestLevel chapter",
                 chapter,
-                "The level replaces this chapter of world 9 (TestLevel) when it is enabled");
+                "The level replaces this chapter of world 9 (TestLevel) when it is enabled (32–49; 1 is the Test"
+                        + " World's)");
         JPanel templates = new JPanel();
         templates.setLayout(new BoxLayout(templates, BoxLayout.Y_AXIS));
         ButtonGroup g = new ButtonGroup();
@@ -161,7 +164,7 @@ final class NewLevelDialog extends JDialog {
         return row + 1;
     }
 
-    /** First TestLevel chapter from 2 that no project in the levels folder uses. */
+    /** First usable TestLevel chapter from 32 that no project in the levels folder uses. */
     static int nextFreeChapter(EditorWindow w) {
         Set<Integer> used = new HashSet<>();
         for (Path p : LevelProjects.list(w.env().levelsDir())) {
@@ -174,11 +177,7 @@ final class NewLevelDialog extends JDialog {
                 // skip broken files
             }
         }
-        int c = 2;
-        while (used.contains(c) && c < 49) {
-            c++;
-        }
-        return c;
+        return TestLevelChapters.pick(TestLevelChapters.FIRST, used);
     }
 
     Result result() {

src/main/java/com/eliasmueller/llamamod/editor/ui/ProjectController.java

@@ -15,6 +15,7 @@ import com.eliasmueller.llamamod.editor.model.cmd.AddNode;
 import com.eliasmueller.llamamod.editor.model.cmd.Batch;
 import com.eliasmueller.llamamod.editor.model.cmd.Command;
 import com.eliasmueller.llamamod.platform.Json;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.awt.RenderingHints;
 import java.awt.image.BufferedImage;
 import java.io.File;
@@ -592,7 +593,7 @@ public final class ProjectController {
                 ? String.format(
                         Locale.ROOT,
                         "T1L9M%03d",
-                        Math.max(1, d.scene().settings().targetChapter()))
+                        TestLevelChapters.migrate(d.scene().settings().targetChapter()))
                 : d.base();
         fc.setSelectedFile(new File(fc.getCurrentDirectory(), stem + ".wad"));
         if (fc.showSaveDialog(w) != JFileChooser.APPROVE_OPTION) {

src/main/java/com/eliasmueller/llamamod/format/stpcmerge/TextMerge.java

@@ -1,6 +1,8 @@
 package com.eliasmueller.llamamod.format.stpcmerge;
 
 import com.eliasmueller.llamamod.format.TextChunk;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -87,6 +89,41 @@ public final class TextMerge {
         }
     }
 
+    /**
+     * TEXT chunk {@code orig} with the pages, entries and animations of {@code tex} (usually
+     * {@code Textures.of(orig)} extended by {@link #merge}); palettes and the rest are kept.
+     */
+    public static byte[] rebuild(byte[] orig, Textures tex) {
+        Textures old = Textures.of(orig);
+        int head = 8 + 8 * old.entries.size();
+        for (Anim a : old.anims) {
+            head += 3 + a.data().length;
+        }
+        TextChunk tc = TextChunk.parse(orig);
+        byte[] rest = Arrays.copyOfRange(tc.tail, head, tc.tail.length);
+        ByteBuffer b = ByteBuffer.allocate(8 + 8 * tex.entries.size() + tex.anims.size() * 64 + rest.length + 1024)
+                .order(ByteOrder.LITTLE_ENDIAN);
+        b.putInt(tex.entries.size());
+        for (TextChunk.TextureEntry e : tex.entries) {
+            b.putShort((short) e.flags())
+                    .put((byte) e.page())
+                    .put((byte) e.page2())
+                    .put((byte) e.u0())
+                    .put((byte) e.u1())
+                    .put((byte) e.v0())
+                    .put((byte) e.v1());
+        }
+        b.putInt(tex.anims.size());
+        for (Anim a : tex.anims) {
+            b.putShort((short) a.texture()).put((byte) a.type()).put(a.data());
+        }
+        b.put(rest);
+        tc.pages.clear();
+        tc.pages.addAll(tex.pages);
+        tc.tail = Arrays.copyOf(b.array(), b.position());
+        return tc.build();
+    }
+
     /** Result: map[srcIndex] = target index (−1 = not needed), counts of added items. */
     public record Result(int[] map, int addedPages, int addedEntries, int addedAnims, int reusedEntries) {}
 

src/main/java/com/eliasmueller/llamamod/mods/arena/ArenaImport.java

@@ -3,7 +3,6 @@ package com.eliasmueller.llamamod.mods.arena;
 import com.eliasmueller.llamamod.format.Bytes;
 import com.eliasmueller.llamamod.format.Level;
 import com.eliasmueller.llamamod.format.MapChunk;
-import com.eliasmueller.llamamod.format.TextChunk;
 import com.eliasmueller.llamamod.format.Wad;
 import com.eliasmueller.llamamod.format.stpcmerge.DialogMerge;
 import com.eliasmueller.llamamod.format.stpcmerge.SoundMerge;
@@ -106,10 +105,6 @@ final class ArenaImport {
         StpcMerge.Analysis tgt = new StpcMerge.Analysis(new StpcImage(wad.require("STPC"), lv.wfpc()), troots);
         byte[] text = wad.require("TEXT");
         TextMerge.Textures tex = TextMerge.Textures.of(text);
-        int origTail = 8 + 8 * tex.entries.size();
-        for (TextMerge.Anim a : tex.anims) {
-            origTail += 3 + a.data().length;
-        }
         List<SoundMerge.Sample> snd = SoundMerge.parse(wad.get("SMPC"));
         DialogMerge.Texts texts = wad.get("LGPC") == null ? null : DialogMerge.Texts.parse(wad.get("LGPC"));
         DialogMerge.Speech speech = DialogMerge.Speech.parse(wad.get("SRPC"));
@@ -143,40 +138,13 @@ final class ArenaImport {
         Wad out = new Wad(wad.chunks());
         out.set("STPC", res.stpc());
         out.set("MAP", map.build());
-        out.set("TEXT", text(text, tex, origTail));
+        out.set("TEXT", TextMerge.rebuild(text, tex));
         if (wad.get("SMPC") != null) {
             out.set("SMPC", SoundMerge.build(snd));
         }
         return new Merged(out.toBytes(), codes, res.stats());
     }
 
-    /** TEXT chunk with the (extended) pages, entries and animations of tex; the rest is kept. */
-    private static byte[] text(byte[] orig, TextMerge.Textures tex, int origTailHead) {
-        TextChunk tc = TextChunk.parse(orig);
-        byte[] rest = Arrays.copyOfRange(tc.tail, origTailHead, tc.tail.length);
-        ByteBuffer b = ByteBuffer.allocate(8 + 8 * tex.entries.size() + tex.anims.size() * 64 + rest.length + 1024)
-                .order(ByteOrder.LITTLE_ENDIAN);
-        b.putInt(tex.entries.size());
-        for (TextChunk.TextureEntry e : tex.entries) {
-            b.putShort((short) e.flags())
-                    .put((byte) e.page())
-                    .put((byte) e.page2())
-                    .put((byte) e.u0())
-                    .put((byte) e.u1())
-                    .put((byte) e.v0())
-                    .put((byte) e.v1());
-        }
-        b.putInt(tex.anims.size());
-        for (TextMerge.Anim a : tex.anims) {
-            b.putShort((short) a.texture()).put((byte) a.type()).put(a.data());
-        }
-        b.put(rest);
-        tc.pages.clear();
-        tc.pages.addAll(tex.pages);
-        tc.tail = Arrays.copyOf(b.array(), b.position());
-        return tc.build();
-    }
-
     private static void putI32(byte[] d, int o, int v) {
         ByteBuffer.wrap(d, o, 4).order(ByteOrder.LITTLE_ENDIAN).putInt(v);
     }

src/main/java/com/eliasmueller/llamamod/mods/arena/ArenaMod.java

@@ -5,6 +5,8 @@ import com.eliasmueller.llamamod.levelbuild.LevelBuilder;
 import com.eliasmueller.llamamod.mods.Mod;
 import com.eliasmueller.llamamod.mods.ModContext;
 import com.eliasmueller.llamamod.mods.ModOption;
+import com.eliasmueller.llamamod.mods.levels.LevelTally;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.awt.Color;
 import java.awt.Font;
 import java.awt.FontMetrics;
@@ -53,7 +55,29 @@ public final class ArenaMod implements Mod {
                 ModOption.integer(
                         "energy", "Llama energy", "Energy cap of the llama in the arena (5 = normal).", 4, 1, 5),
                 ModOption.integer("coins", "Coins per hit", "Coins that pop out per hit (5 more at the end).", 1, 0, 5),
-                ModOption.integer("chapter", "TestLevel chapter", "Chapter of world 9 the arena replaces.", 8, 2, 8));
+                chapterOption());
+    }
+
+    static final int DEFAULT_CHAPTER = TestLevelChapters.LAST;
+
+    /** TestLevel chapters 32–49 ({@link TestLevelChapters}); a stored 2–8 falls back to 49. */
+    static ModOption chapterOption() {
+        ModOption.Choice[] cs = new ModOption.Choice[TestLevelChapters.LAST - TestLevelChapters.FIRST + 1];
+        for (int c = TestLevelChapters.FIRST; c <= TestLevelChapters.LAST; c++) {
+            cs[c - TestLevelChapters.FIRST] = ModOption.of(Integer.toString(c), Integer.toString(c));
+        }
+        return ModOption.choice(
+                "chapter",
+                "TestLevel chapter",
+                "Chapter of world 9 the arena replaces (32–49; chapter 1 is the Test World's).",
+                Integer.toString(DEFAULT_CHAPTER),
+                cs);
+    }
+
+    /** Coins the arena can give beyond its placed ones: hit and death coins of every alligator, exit bonus. */
+    static int dynamicCoins(ArenaScripts.Settings s) {
+        int perGator = (s.lives() - 1) * s.coinsPerHit() + 5;
+        return ArenaScripts.totalAlligators(s.waves()) * perGator + 5;
     }
 
     /** After Test World (50) and level projects (60), so a clash with them is reported here. */
@@ -95,7 +119,8 @@ public final class ArenaMod implements Mod {
         }
         ctx.progress(0.0, "building alligator arena");
         byte[] base = ctx.read(LevelBuilder.BASE_WAD);
-        byte[] wad = new Arena(settings(ctx))
+        ArenaScripts.Settings settings = settings(ctx);
+        byte[] wad = new Arena(settings)
                 .buildWad(
                         base,
                         rel -> {
@@ -106,7 +131,7 @@ public final class ArenaMod implements Mod {
                             }
                         },
                         scriptOpts);
-        ctx.write(target, wad);
+        ctx.write(target, LevelTally.counted(wad, dynamicCoins(settings)));
         ctx.progress(0.9, "loading picture");
         ctx.write("T19" + chapter + ".COR", loadingPicture(chapter));
         ctx.progress(1.0, "arena done");

src/main/java/com/eliasmueller/llamamod/mods/levels/LevelProjectMod.java

@@ -10,6 +10,7 @@ import com.eliasmueller.llamamod.mods.ModContext;
 import com.eliasmueller.llamamod.mods.ModOption;
 import com.eliasmueller.llamamod.mods.boottolevel.BootToLevelMod;
 import com.eliasmueller.llamamod.mods.boottolevel.StartOverride;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -129,14 +130,22 @@ public final class LevelProjectMod implements Mod {
         if (!info.isNewLevel()) {
             return List.of();
         }
-        return List.of(ModOption.integer(
-                "chapter",
-                "TestLevel chapter",
-                "Chapter of world 9 (TestLevel) the level replaces. Chapter 1 is also used by the Test World mod;"
-                        + " each level needs its own chapter. Unlock it on the Save games tab.",
-                defaultChapter,
-                1,
-                49));
+        return List.of(chapterOption(
+                "Chapter of world 9 (TestLevel) the level replaces: 32–49, or 1 (the Test World's chapter). Each"
+                        + " level needs its own chapter. Unlock it on the Save games tab.",
+                defaultChapter));
+    }
+
+    /**
+     * TestLevel chapter choice: the usable chapters ({@link TestLevelChapters}); a stored value
+     * outside them (2–31 from older versions) falls back to {@code def}.
+     */
+    private static ModOption chapterOption(String description, int def) {
+        ModOption.Choice[] cs = TestLevelChapters.all().stream()
+                .map(c -> ModOption.of(
+                        Integer.toString(c), c == TestLevelChapters.TEST_WORLD ? "1 (Test World)" : "" + c))
+                .toArray(ModOption.Choice[]::new);
+        return ModOption.choice("chapter", "TestLevel chapter", description, Integer.toString(def), cs);
     }
 
     /** CD path of the WAD this mod writes. */
@@ -160,7 +169,8 @@ public final class LevelProjectMod implements Mod {
                 throw new IOException("Level \"" + name() + "\": " + target + " is already changed by another mod ("
                         + (info.isNewLevel()
                                 ? "Test World or another level on TestLevel chapter " + chapter
-                                        + "). Choose a free chapter in the options of \"" + name() + "\""
+                                        + "). Choose a free chapter in the options of \"" + name()
+                                        + "\" or turn one of them off"
                                 : "two mods change the same level). Turn one of them off")
                         + ".");
             }
@@ -174,6 +184,9 @@ public final class LevelProjectMod implements Mod {
             throw new IOException("Level \"" + name() + "\": " + bad + ". Move the Llama onto walkable ground in"
                     + " the level editor.");
         }
+        if (info.isNewLevel()) {
+            wad = LevelTally.counted(wad);
+        }
         ctx.write(target, wad);
         if (info.isNewLevel()) {
             ctx.progress(0.9, "loading picture");

src/main/java/com/eliasmueller/llamamod/mods/levels/LevelProjectSource.java

@@ -5,18 +5,21 @@ import com.eliasmueller.llamamod.editor.io.ProjectInfo;
 import com.eliasmueller.llamamod.mods.Mod;
 import com.eliasmueller.llamamod.mods.ModSource;
 import com.eliasmueller.llamamod.platform.AppPaths;
+import com.eliasmueller.llamamod.save.TestLevelChapters;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 
 /**
  * One mod per {@code .llamalevel} file in {@code <data>/levels/} (category "levels"). New levels
- * get a default TestLevel chapter: their stored target, or the next free one if another project
- * already uses it. Temporary play-test copies in {@code levels/.playtest/} are listed too, with
+ * get a default TestLevel chapter: their stored target, or the next free usable one if another
+ * project already uses it or it is not usable ({@link TestLevelChapters}; old projects on 2–31). Temporary play-test copies in {@code levels/.playtest/} are listed too, with
  * ids {@code playtest-…}.
  */
 public final class LevelProjectSource implements ModSource {
@@ -32,57 +35,57 @@ public final class LevelProjectSource implements ModSource {
 
     @Override
     public List<Mod> mods() {
-        List<Mod> out = new ArrayList<>();
-        Set<Integer> used = new HashSet<>();
         List<Path> levels = LevelProjects.list(dir);
         List<Path> tests = LevelProjects.list(LevelProjects.playtestDir(dir));
         Set<String> bases = new HashSet<>();
         levels.forEach(p -> bases.add(LevelProjectMod.baseId(p, false)));
         tests.forEach(p -> bases.add(LevelProjectMod.baseId(p, true)));
-        Set<String> ids = new HashSet<>();
-        for (Path p : levels) {
-            add(p, false, used, bases, ids, out);
+        List<Entry> all = new ArrayList<>();
+        levels.forEach(p -> read(p, false, all));
+        tests.forEach(p -> read(p, true, all));
+        // usable stored chapters first (first file wins), so a moved old project never displaces them
+        Map<Entry, Integer> chapters = new HashMap<>();
+        Set<Integer> used = new HashSet<>();
+        for (Entry e : all) {
+            int c = e.info.targetChapter();
+            if (e.info.isNewLevel() && !e.playtest && TestLevelChapters.usable(c) && used.add(c)) {
+                chapters.put(e, c);
+            }
         }
-        for (Path p : tests) {
-            add(p, true, used, bases, ids, out);
+        List<Mod> out = new ArrayList<>();
+        Set<String> ids = new HashSet<>();
+        for (Entry e : all) {
+            int chapter = 0;
+            if (e.info.isNewLevel() && e.playtest) {
+                chapter = TestLevelChapters.migrate(e.info.targetChapter());
+            } else if (e.info.isNewLevel()) {
+                chapter = chapters.computeIfAbsent(e, k -> TestLevelChapters.pick(k.info.targetChapter(), used));
+                used.add(chapter);
+            }
+            // names differing only in case or punctuation share an id: later ones get a suffix no other file has
+            String base = LevelProjectMod.baseId(e.file, e.playtest);
+            String id = base;
+            if (!ids.add(id)) {
+                int i = 2;
+                while (bases.contains(base + "-" + i) || ids.contains(base + "-" + i)) {
+                    i++;
+                }
+                id = base + "-" + i;
+                ids.add(id);
+            }
+            out.add(new LevelProjectMod(e.file, e.data, e.info, chapter, id, e.playtest));
         }
         return out;
     }
 
-    private static void add(
-            Path p, boolean playtest, Set<Integer> used, Set<String> bases, Set<String> ids, List<Mod> out) {
-        byte[] d;
-        ProjectInfo info;
+    private record Entry(Path file, boolean playtest, byte[] data, ProjectInfo info) {}
+
+    private static void read(Path p, boolean playtest, List<Entry> out) {
         try {
-            d = Files.readAllBytes(p);
-            info = ProjectIO.info(d);
+            byte[] d = Files.readAllBytes(p);
+            out.add(new Entry(p, playtest, d, ProjectIO.info(d)));
         } catch (IOException | RuntimeException e) {
-            return;
+            // unreadable or broken: not listed
         }
-        int chapter = 0;
-        if (info.isNewLevel() && playtest) {
-            chapter = Math.max(1, Math.min(49, info.targetChapter()));
-        } else if (info.isNewLevel()) {
-            chapter = info.targetChapter();
-            if (chapter < 1 || chapter > 49 || used.contains(chapter)) {
-                chapter = 2;
-                while (used.contains(chapter) && chapter < 49) {
-                    chapter++;
-                }
-            }
-            used.add(chapter);
-        }
-        // names differing only in case or punctuation share an id: later ones get a suffix no other file has
-        String base = LevelProjectMod.baseId(p, playtest);
-        String id = base;
-        if (!ids.add(id)) {
-            int i = 2;
-            while (bases.contains(base + "-" + i) || ids.contains(base + "-" + i)) {
-                i++;
-            }
-            id = base + "-" + i;
-            ids.add(id);
-        }
-        out.add(new LevelProjectMod(p, d, info, chapter, id, playtest));
     }
 }

src/main/java/com/eliasmueller/llamamod/mods/levels/LevelTally.java

@@ -0,0 +1,58 @@
+package com.eliasmueller.llamamod.mods.levels;
+
+import com.eliasmueller.llamamod.format.Level;
+import com.eliasmueller.llamamod.format.MapChunk;
+import com.eliasmueller.llamamod.format.Strats;
+import com.eliasmueller.llamamod.format.Wad;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * The level tally's totals ("Münzen gesammelt n / total", "Geheimnisse entdeckt n / total"): chunk
+ * LNFO = u32 coins, u32 secrets (→ 0x5ff070 / 0x5ff060, FUN_0042ab10). Levels built on a base keep
+ * the base's numbers (Village: 55, 2) unless they are recounted here.
+ */
+public final class LevelTally {
+    private LevelTally() {}
+
+    /**
+     * Placed coins (Coin = 1, Coin5 = 5) and Secret strats of a level WAD. Other coin sources
+     * (CoinLine, CoinCircle, enemies' EnemyCoins …) are not counted.
+     */
+    public static int[] count(byte[] wad) {
+        Level lv = Level.parse(wad);
+        Map<String, List<MapChunk.Strat>> t = Strats.levelTypes(lv.wad().require("STPC"), lv.wfpc(), lv.map());
+        int coins = n(t, "Coin") + 5 * n(t, "Coin5");
+        return new int[] {coins, n(t, "Secret")};
+    }
+
+    private static int n(Map<String, List<MapChunk.Strat>> t, String type) {
+        List<MapChunk.Strat> l = t.get(type);
+        return l == null ? 0 : l.size();
+    }
+
+    /** {@code wad} with LNFO set to {@link #count} plus {@code extraCoins}; unchanged without LNFO. */
+    public static byte[] counted(byte[] wad, int extraCoins) {
+        int[] c = count(wad);
+        return withTotals(wad, c[0] + extraCoins, c[1]);
+    }
+
+    public static byte[] counted(byte[] wad) {
+        return counted(wad, 0);
+    }
+
+    /** {@code wad} with LNFO = (coins, secrets); unchanged if it has no LNFO chunk. */
+    public static byte[] withTotals(byte[] wad, int coins, int secrets) {
+        Wad w = Wad.parse(wad);
+        byte[] old = w.get("LNFO");
+        if (old == null || old.length < 8) {
+            return wad;
+        }
+        byte[] ln = old.clone();
+        ByteBuffer.wrap(ln).order(ByteOrder.LITTLE_ENDIAN).putInt(0, coins).putInt(4, secrets);
+        w.set("LNFO", ln);
+        return w.toBytes();
+    }
+}

src/main/java/com/eliasmueller/llamamod/mods/testworld/Gallery.java

@@ -412,10 +412,6 @@ public final class Gallery {
         StpcMerge.Analysis tgt = new StpcMerge.Analysis(ti, roots);
         byte[] text = wad.require("TEXT");
         TextMerge.Textures tex = TextMerge.Textures.of(text);
-        int origTail = 8 + 8 * tex.entries.size();
-        for (TextMerge.Anim a : tex.anims) {
-            origTail += 3 + a.data().length;
-        }
         List<SoundMerge.Sample> snd = SoundMerge.parse(wad.get("SMPC"));
         DialogMerge.Texts texts = wad.get("LGPC") == null ? null : DialogMerge.Texts.parse(wad.get("LGPC"));
         DialogMerge.Speech speech = DialogMerge.Speech.parse(wad.get("SRPC"));
@@ -463,34 +459,7 @@ public final class Gallery {
         Wad out = new Wad(wad.chunks());
         out.set("STPC", res.stpc());
         out.set("MAP", map.build());
-        out.set("TEXT", text(text, tex, origTail));
+        out.set("TEXT", TextMerge.rebuild(text, tex));
         return new Merged(out.toBytes(), codes, res.stats());
     }
-
-    /** TEXT chunk with the (extended) pages, entries and animations of tex; the rest is kept. */
-    private static byte[] text(byte[] orig, TextMerge.Textures tex, int origTailHead) {
-        TextChunk tc = TextChunk.parse(orig);
-        byte[] rest = Arrays.copyOfRange(tc.tail, origTailHead, tc.tail.length);
-        ByteBuffer b = ByteBuffer.allocate(8 + 8 * tex.entries.size() + tex.anims.size() * 64 + rest.length + 1024)
-                .order(java.nio.ByteOrder.LITTLE_ENDIAN);
-        b.putInt(tex.entries.size());
-        for (TextChunk.TextureEntry e : tex.entries) {
-            b.putShort((short) e.flags())
-                    .put((byte) e.page())
-                    .put((byte) e.page2())
-                    .put((byte) e.u0())
-                    .put((byte) e.u1())
-                    .put((byte) e.v0())
-                    .put((byte) e.v1());
-        }
-        b.putInt(tex.anims.size());
-        for (TextMerge.Anim a : tex.anims) {
-            b.putShort((short) a.texture()).put((byte) a.type()).put(a.data());
-        }
-        b.put(rest);
-        tc.pages.clear();
-        tc.pages.addAll(tex.pages);
-        tc.tail = Arrays.copyOf(b.array(), b.position());
-        return tc.build();
-    }
 }

src/main/java/com/eliasmueller/llamamod/mods/testworld/TestWorldMod.java

@@ -4,6 +4,7 @@ import com.eliasmueller.llamamod.format.CorEncoder;
 import com.eliasmueller.llamamod.levelbuild.LevelBuilder;
 import com.eliasmueller.llamamod.mods.Mod;
 import com.eliasmueller.llamamod.mods.ModContext;
+import com.eliasmueller.llamamod.mods.levels.LevelTally;
 import java.awt.image.BufferedImage;
 import java.io.IOException;
 import java.io.InputStream;
@@ -59,7 +60,7 @@ public final class TestWorldMod implements Mod {
                             }
                         },
                         Map.of());
-        ctx.write(OUT_WAD, wad);
+        ctx.write(OUT_WAD, LevelTally.counted(wad));
         ctx.progress(0.9, "loading picture");
         ctx.write(LOADING_PICTURE, loadingPicture());
         ctx.progress(1.0, "test world done");

src/main/java/com/eliasmueller/llamamod/save/TestLevelChapters.java

@@ -0,0 +1,76 @@
+package com.eliasmueller.llamamod.save;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+/**
+ * TestLevel (world 9) chapters a mod level may occupy. The game has per-chapter arrays only for
+ * worlds 1–8: the coin counter u32 0x584F1C[world·6 + chapter] and the flag byte
+ * 0x584EC8[world·6 + chapter]. For world 9 both run into other globals, which the game zeroes on
+ * level start and overwrites with coins or flags:
+ *
+ * <pre>
+ * coin slot 0x584FF4 + 4c: c=0 counter var 0xC0, 1 unused, 2 counter var 0xBF, 3 HUD flag 0x585000,
+ *   4 var 0x80, 5..8 last played tribe/world/chapter/map (0x585008..14), 9 furthest progress
+ *   (0x585018: zeroed on level start, coins make it garbage), 10..21 unused, 22..31 byte table
+ *   0x585024 (strat var 0x93, tribe 1), 32..49 the same table for tribes 2/3 (never used).
+ * flag byte 0x584EFE + c: 0..5 unused, 6..9 language index 0x584F04 (|=2 → wrong texts/crash),
+ *   10..13 option 0x584F08, 14..21 0x584F0C/0x584F10, 22..25 unused, 26..29 option 0x584F18,
+ *   30..49 coin slots of world 0 (never read).
+ * </pre>
+ *
+ * Safe: chapter 1 (Test World) and 32–49.
+ */
+public final class TestLevelChapters {
+    private TestLevelChapters() {}
+
+    /** The Test World's chapter. */
+    public static final int TEST_WORLD = 1;
+
+    /** First and last chapter for other mod levels. */
+    public static final int FIRST = 32;
+
+    public static final int LAST = 49;
+
+    public static boolean usable(int chapter) {
+        return chapter == TEST_WORLD || chapter >= FIRST && chapter <= LAST;
+    }
+
+    /** All usable chapters: 1, 32..49. */
+    public static List<Integer> all() {
+        List<Integer> out = new ArrayList<>();
+        out.add(TEST_WORLD);
+        for (int c = FIRST; c <= LAST; c++) {
+            out.add(c);
+        }
+        return out;
+    }
+
+    /**
+     * A usable chapter for a stored one: unchanged if usable, else 2..19 → 32..49, 20..31 → 32..43,
+     * anything else → 32 (deterministic, for play-tests and exports of old projects).
+     */
+    public static int migrate(int chapter) {
+        if (usable(chapter)) {
+            return chapter;
+        }
+        return chapter >= 2 && chapter < FIRST ? FIRST + (chapter - 2) % (LAST - FIRST + 1) : FIRST;
+    }
+
+    /**
+     * {@code wanted} if usable and not in {@code used}, else the first free chapter of 32..49; when
+     * all are taken, {@link #migrate}({@code wanted}) (shared: only one of those levels can be on).
+     */
+    public static int pick(int wanted, Collection<Integer> used) {
+        if (usable(wanted) && !used.contains(wanted)) {
+            return wanted;
+        }
+        for (int c = FIRST; c <= LAST; c++) {
+            if (!used.contains(c)) {
+                return c;
+            }
+        }
+        return migrate(wanted);
+    }
+}

src/test/java/com/eliasmueller/llamamod/editor/tools/playtest/PlaytestLifecycleTest.java

@@ -76,7 +76,10 @@ class PlaytestLifecycleTest {
         assertNotNull(t);
         assertTrue(t.playtest());
         assertTrue(t.name().endsWith("(play-test)"));
-        assertEquals("4", t.options().getFirst().defaultValue(), "own chapter, not shifted by the saved level");
+        assertEquals(
+                "34",
+                t.options().getFirst().defaultValue(),
+                "own chapter (old 4 → 34), not shifted by the saved level");
         assertFalse(mod("level-mine").playtest());
 
         cfg.enabledMods = new ArrayList<>(List.of("fog", "playtest-mine"));

src/test/java/com/eliasmueller/llamamod/mods/arena/ArenaTest.java

@@ -5,6 +5,7 @@ import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import com.eliasmueller.llamamod.format.Bytes;
 import com.eliasmueller.llamamod.format.Level;
 import com.eliasmueller.llamamod.format.MapChunk;
 import com.eliasmueller.llamamod.format.Strats;
@@ -13,8 +14,11 @@ import com.eliasmueller.llamamod.format.stpcmerge.StratCode;
 import com.eliasmueller.llamamod.format.strat.StratCompiler;
 import com.eliasmueller.llamamod.format.strat.StratListing;
 import com.eliasmueller.llamamod.mods.GameData;
+import com.eliasmueller.llamamod.mods.ModOption;
+import com.eliasmueller.llamamod.mods.ModOptions;
 import com.eliasmueller.llamamod.mods.ModRegistry;
 import com.eliasmueller.llamamod.mods.TestModContext;
+import com.eliasmueller.llamamod.platform.Config;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.ArrayList;
@@ -89,11 +93,11 @@ class ArenaTest {
     void builtLevel() throws IOException {
         Path cd = GameData.cd();
         ArenaMod mod = new ArenaMod();
-        TestModContext ctx = new TestModContext(cd, mod, Map.of("lives", "7", "chapter", "5"), null);
+        TestModContext ctx = new TestModContext(cd, mod, Map.of("lives", "7", "chapter", "40"), null);
         mod.apply(ctx);
-        byte[] wad = ctx.written.get("wads/T1L9M005.wad");
+        byte[] wad = ctx.written.get("wads/T1L9M040.wad");
         assertNotNull(wad, "written: " + ctx.written.keySet());
-        assertNotNull(ctx.written.get("T195.COR"));
+        assertNotNull(ctx.written.get("T1940.COR"));
 
         Level lv = Level.parse(wad);
         Map<String, List<MapChunk.Strat>> t = types(lv);
@@ -101,6 +105,9 @@ class ArenaTest {
         assertEquals(1, t.get("ArenaMaster").size());
         assertEquals(1, t.get("CheckPointPost").size());
         assertEquals(2, t.get("Coin").size());
+        // tally total: 2 placed + 5 alligators · (6 hit coins + 5 death coins) + 5 exit bonus
+        assertEquals(2 + 5 * (6 + 5) + 5, Bytes.u32(lv.wad().require("LNFO"), 0));
+        assertEquals(0, Bytes.u32(lv.wad().require("LNFO"), 4));
         assertTrue(
                 !t.containsKey("LevelDoor") && !t.containsKey("ArenaGator"),
                 t.keySet().toString());
@@ -140,9 +147,9 @@ class ArenaTest {
         Path cd = GameData.cd();
         ArenaMod mod = new ArenaMod();
         TestModContext ctx = new TestModContext(cd, mod, Map.of(), null);
-        ctx.write("wads/T1L9M008.wad", new byte[] {1, 2, 3});
+        ctx.write("wads/T1L9M049.wad", new byte[] {1, 2, 3});
         IOException e = assertThrows(IOException.class, () -> mod.apply(ctx));
-        assertTrue(e.getMessage().contains("chapter 8"), e.getMessage());
+        assertTrue(e.getMessage().contains("chapter 49"), e.getMessage());
     }
 
     @Test
@@ -151,9 +158,27 @@ class ArenaTest {
         ArenaMod mod = new ArenaMod();
         TestModContext ctx = new TestModContext(cd, mod, Map.of(), null);
         ArenaMod.apply(ctx, Map.of("probe", "true", "master", "false"));
-        Level lv = Level.parse(ctx.written.get("wads/T1L9M008.wad"));
+        Level lv = Level.parse(ctx.written.get("wads/T1L9M049.wad"));
         Map<String, List<MapChunk.Strat>> t = types(lv);
         assertEquals(1, t.get("ArenaProbe").size());
         assertTrue(!t.containsKey("ArenaMaster"), new ArrayList<>(t.keySet()).toString());
     }
+
+    @Test
+    void chapterIsUsableOnly() {
+        ModOption o = new ArenaMod()
+                .options().stream()
+                        .filter(x -> x.key().equals("chapter"))
+                        .findFirst()
+                        .orElseThrow();
+        assertEquals("49", o.defaultValue());
+        assertEquals("32", o.normalize("32"));
+        for (String bad : List.of("1", "8", "9", "31", "50")) {
+            assertThrows(IllegalArgumentException.class, () -> o.normalize(bad), bad);
+        }
+        // a stored chapter from the old range 2..8 falls back to the default
+        Config cfg = new Config();
+        cfg.modOptions.put("arena", Map.of("chapter", "8"));
+        assertEquals("49", ModOptions.resolve(new ArenaMod(), cfg).get("chapter"));
+    }
 }

src/test/java/com/eliasmueller/llamamod/mods/arena/ArenaTestMod.java

@@ -12,7 +12,7 @@ import java.util.Map;
 /**
  * The arena with level script options for in-game tests (not registered): {@code
  * APPTEST_CP=build/classes/java/test APPTEST_JAVA_OPTS=-Dllamamod.extraMods=<this class>}, option
- * {@code script} = {@code key=value;key=value} (probe=true, start=x,z,rot).
+ * {@code script} = {@code key=value;key=value} (probe=true, start=x,z,rot); {@code chapter} 1–49.
  */
 public final class ArenaTestMod implements Mod {
     @Override
@@ -32,7 +32,14 @@ public final class ArenaTestMod implements Mod {
 
     @Override
     public List<ModOption> options() {
-        List<ModOption> o = new ArrayList<>(new ArenaMod().options());
+        List<ModOption> o = new ArrayList<>();
+        for (ModOption x : new ArenaMod().options()) {
+            // any chapter, to reproduce the per-chapter memory clashes of unusable ones
+            o.add(
+                    x.key().equals("chapter")
+                            ? ModOption.integer("chapter", x.label(), x.description(), ArenaMod.DEFAULT_CHAPTER, 1, 49)
+                            : x);
+        }
         o.add(ModOption.string("script", "Script options", "key=value;…", ""));
         return o;
     }

src/test/java/com/eliasmueller/llamamod/mods/levels/LevelProjectModTest.java

@@ -10,10 +10,13 @@ import com.eliasmueller.llamamod.editor.io.ProjectIO;
 import com.eliasmueller.llamamod.editor.model.Strat;
 import com.eliasmueller.llamamod.editor.model.cmd.Edits;
 import com.eliasmueller.llamamod.editor.model.cmd.History;
+import com.eliasmueller.llamamod.format.Bytes;
 import com.eliasmueller.llamamod.format.Level;
 import com.eliasmueller.llamamod.mods.GameData;
 import com.eliasmueller.llamamod.mods.Mod;
+import com.eliasmueller.llamamod.mods.ModOptions;
 import com.eliasmueller.llamamod.mods.TestModContext;
+import com.eliasmueller.llamamod.platform.Config;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -38,10 +41,10 @@ class LevelProjectModTest {
         ProjectIO.save(edit, dir.resolve("village edit.llamalevel"), cd);
         Project a = Project.create(cd, "new", "t1l1m001");
         a.scene().settings().prop("name").setRaw(a.scene().settings(), "Level A");
-        a.scene().settings().prop("targetChapter").setRaw(a.scene().settings(), 3);
+        a.scene().settings().prop("targetChapter").setRaw(a.scene().settings(), 40);
         ProjectIO.save(a, dir.resolve("a.llamalevel"), cd);
         Project b = Project.create(cd, "new", "t1l1m001");
-        b.scene().settings().prop("targetChapter").setRaw(b.scene().settings(), 3);
+        b.scene().settings().prop("targetChapter").setRaw(b.scene().settings(), 40);
         ProjectIO.save(b, dir.resolve("b.llamalevel"), cd);
         Files.writeString(dir.resolve("broken.llamalevel"), "no zip");
 
@@ -52,17 +55,20 @@ class LevelProjectModTest {
         LevelProjectMod ma = (LevelProjectMod) mods.get(0);
         LevelProjectMod mb = (LevelProjectMod) mods.get(1);
         LevelProjectMod me = (LevelProjectMod) mods.get(2);
-        assertEquals("3", ma.options().getFirst().defaultValue());
-        assertEquals("2", mb.options().getFirst().defaultValue(), "chapter 3 is taken: next free");
+        assertEquals("40", ma.options().getFirst().defaultValue());
+        assertEquals("32", mb.options().getFirst().defaultValue(), "chapter 40 is taken: first free usable");
         assertTrue(me.options().isEmpty());
         assertEquals(Mod.LEVELS, me.category());
 
         TestModContext ctx = new TestModContext(cdDir, ma, Map.of(), null);
         ma.apply(ctx);
-        assertTrue(ctx.written.containsKey("wads/T1L9M003.wad"));
-        assertTrue(ctx.written.containsKey("T193.COR"));
-        Level lv = Level.parse(ctx.written.get("wads/T1L9M003.wad"));
+        assertTrue(ctx.written.containsKey("wads/T1L9M040.wad"));
+        assertTrue(ctx.written.containsKey("T1940.COR"));
+        Level lv = Level.parse(ctx.written.get("wads/T1L9M040.wad"));
         assertEquals(0, lv.map().strats.size());
+        byte[] lnfo = lv.wad().get("LNFO");
+        assertEquals(0, Bytes.u32(lnfo, 0), "tally: no coins (not the base's 55)");
+        assertEquals(0, Bytes.u32(lnfo, 4), "tally: no secrets");
 
         TestModContext ec = new TestModContext(cdDir, me, Map.of(), null);
         me.apply(ec);
@@ -78,7 +84,7 @@ class LevelProjectModTest {
         IOException e = assertThrows(IOException.class, () -> me.apply(twice));
         assertTrue(e.getMessage().contains("already changed"), e.getMessage());
         TestModContext both = new TestModContext(cdDir, ma, Map.of(), null);
-        both.written.put("wads/T1L9M003.wad", new byte[] {1});
+        both.written.put("wads/T1L9M040.wad", new byte[] {1});
         assertThrows(IOException.class, () -> ma.apply(both));
     }
 
@@ -100,4 +106,40 @@ class LevelProjectModTest {
         assertTrue(!v1.equals(v2), "cache key must change with the project file");
         assertEquals(new LevelProjectSource(dir).mods().getFirst().version(), v2);
     }
+
+    @Test
+    void oldChaptersMoveToUsableOnes(@TempDir Path dir) throws IOException {
+        Bases cd = Bases.fromCd(GameData.cd());
+        for (String[] f : new String[][] {{"a", "5"}, {"b", "9"}, {"c", "1"}, {"d", "33"}}) {
+            Project p = Project.create(cd, "new", "t1l1m001");
+            p.scene().settings().prop("targetChapter").setRaw(p.scene().settings(), Integer.parseInt(f[1]));
+            ProjectIO.save(p, dir.resolve(f[0] + ".llamalevel"), cd);
+        }
+        List<Mod> mods = new LevelProjectSource(dir).mods();
+        assertEquals(
+                List.of("32", "34", "1", "33"),
+                mods.stream().map(m -> m.options().getFirst().defaultValue()).toList(),
+                "2..31 → first free of 32..49; 1 and 33 stay");
+        // a chapter stored in the launcher config by an older version falls back to the default
+        Config cfg = new Config();
+        cfg.modOptions.put("level-a", Map.of("chapter", "5"));
+        assertEquals("32", ModOptions.resolve(mods.getFirst(), cfg).get("chapter"));
+        cfg.modOptions.put("level-a", Map.of("chapter", "45"));
+        assertEquals("45", ModOptions.resolve(mods.getFirst(), cfg).get("chapter"));
+    }
+
+    @Test
+    void moreProjectsThanChaptersShareThem(@TempDir Path dir) throws IOException {
+        Bases cd = Bases.fromCd(GameData.cd());
+        Project p = Project.create(cd, "new", "t1l1m001");
+        p.scene().settings().prop("targetChapter").setRaw(p.scene().settings(), 40);
+        for (int i = 0; i < 20; i++) {
+            ProjectIO.save(p, dir.resolve(String.format("p%02d.llamalevel", i)), cd);
+        }
+        List<String> ch = new LevelProjectSource(dir)
+                .mods().stream().map(m -> m.options().getFirst().defaultValue()).toList();
+        assertEquals("40", ch.get(0));
+        assertEquals(18, ch.stream().distinct().count(), ch.toString());
+        assertTrue(ch.stream().allMatch(c -> Integer.parseInt(c) >= 32), ch.toString());
+    }
 }

src/test/java/com/eliasmueller/llamamod/mods/testworld/TestWorldGoldenTest.java

@@ -3,10 +3,13 @@ package com.eliasmueller.llamamod.mods.testworld;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.fail;
 
+import com.eliasmueller.llamamod.format.Bytes;
+import com.eliasmueller.llamamod.format.Level;
 import com.eliasmueller.llamamod.levelbuild.LevelBuilder;
 import com.eliasmueller.llamamod.levelbuild.LevelScript;
 import com.eliasmueller.llamamod.mods.GameData;
 import com.eliasmueller.llamamod.mods.ModContext;
+import com.eliasmueller.llamamod.mods.levels.LevelTally;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -135,7 +138,10 @@ class TestWorldGoldenTest {
             public void progress(double fraction, String message) {}
         });
         assertEquals(List.of("T191.COR", "wads/T1L9M001.wad"), List.copyOf(written.keySet()));
-        assertEquals(TEST_WORLD_SHA, sha256(written.get("wads/T1L9M001.wad")));
+        // the mod only recounts the tally (LNFO: 20 coins, no secrets instead of the Village's 55, 2)
+        byte[] wad = written.get("wads/T1L9M001.wad");
+        assertEquals(20, Bytes.u32(Level.parse(wad).wad().require("LNFO"), 0));
+        assertEquals(TEST_WORLD_SHA, sha256(LevelTally.withTotals(wad, 55, 2)));
         assertEquals(
                 "c55e3babf4855540f14daa60b979a2534e3732037854d9ad785f69f370d095d0", sha256(written.get("T191.COR")));
     }

src/test/java/com/eliasmueller/llamamod/mods/testworld/TestWorldTallyTest.java

@@ -0,0 +1,35 @@
+package com.eliasmueller.llamamod.mods.testworld;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.eliasmueller.llamamod.format.Bytes;
+import com.eliasmueller.llamamod.format.Level;
+import com.eliasmueller.llamamod.format.MapChunk;
+import com.eliasmueller.llamamod.format.Strats;
+import com.eliasmueller.llamamod.mods.GameData;
+import com.eliasmueller.llamamod.mods.TestModContext;
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
+
+/** The tally of the Test World counts its own coins, not the Village base's 55. */
+class TestWorldTallyTest {
+    @Test
+    void lnfoCountsPlacedCoins() throws IOException {
+        TestWorldMod mod = new TestWorldMod();
+        TestModContext ctx = new TestModContext(GameData.cd(), mod, Map.of(), null);
+        mod.apply(ctx);
+        Level lv = Level.parse(ctx.written.get(TestWorldMod.OUT_WAD));
+        Map<String, List<MapChunk.Strat>> t = Strats.levelTypes(lv.wad().require("STPC"), lv.wfpc(), lv.map());
+        int coins = t.getOrDefault("Coin", List.of()).size()
+                + 5 * t.getOrDefault("Coin5", List.of()).size();
+        byte[] lnfo = lv.wad().require("LNFO");
+        System.out.println(
+                "TALLY test world " + Bytes.u32(lnfo, 0) + "/" + Bytes.u32(lnfo, 4) + " types " + t.keySet());
+        assertTrue(coins > 0);
+        assertEquals(coins, Bytes.u32(lnfo, 0));
+        assertEquals(t.getOrDefault("Secret", List.of()).size(), Bytes.u32(lnfo, 4));
+    }
+}

src/test/java/com/eliasmueller/llamamod/save/TestLevelChaptersTest.java

@@ -0,0 +1,57 @@
+package com.eliasmueller.llamamod.save;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+class TestLevelChaptersTest {
+    /** Coin slot 0x584F1C + 4·(54 + c) and flag byte 0x584EC8 + 54 + c of world 9 (see the class comment). */
+    @Test
+    void usableChaptersAvoidTheGlobalsBehindTheArrays() {
+        for (int c = 0; c <= 50; c++) {
+            int coin = 0x584F1C + 4 * (9 * 6 + c);
+            int flag = 0x584EC8 + 9 * 6 + c;
+            boolean coinFree = c == 1
+                    || coin >= 0x58501C && coin < 0x585024
+                    || coin >= 0x585028 && coin < 0x58504C
+                    || coin >= 0x585074 && coin <= 0x5850BB;
+            boolean flagFree = flag < 0x584F04 || flag >= 0x584F14 && flag < 0x584F18 || flag >= 0x584F1C;
+            assertEquals(coinFree && flagFree && c >= 1 && c <= 49, TestLevelChapters.usable(c), "chapter " + c);
+        }
+        assertEquals(19, TestLevelChapters.all().size());
+        assertEquals(0x585018, 0x584F1C + 4 * (9 * 6 + 9), "chapter 9 = furthest progress");
+    }
+
+    @Test
+    void migrate() {
+        assertEquals(1, TestLevelChapters.migrate(1));
+        assertEquals(40, TestLevelChapters.migrate(40));
+        assertEquals(32, TestLevelChapters.migrate(2));
+        assertEquals(38, TestLevelChapters.migrate(8));
+        assertEquals(49, TestLevelChapters.migrate(19));
+        assertEquals(32, TestLevelChapters.migrate(20));
+        assertEquals(43, TestLevelChapters.migrate(31));
+        assertEquals(32, TestLevelChapters.migrate(0));
+        assertEquals(32, TestLevelChapters.migrate(60));
+        for (int c = -1; c < 60; c++) {
+            assertTrue(TestLevelChapters.usable(TestLevelChapters.migrate(c)));
+        }
+    }
+
+    @Test
+    void pick() {
+        assertEquals(40, TestLevelChapters.pick(40, Set.of()));
+        assertEquals(1, TestLevelChapters.pick(1, Set.of(32)));
+        assertEquals(33, TestLevelChapters.pick(40, Set.of(32, 40)));
+        assertEquals(32, TestLevelChapters.pick(5, Set.of()));
+        Set<Integer> full = new HashSet<>(TestLevelChapters.all());
+        assertEquals(38, TestLevelChapters.pick(8, full), "all taken: shared");
+        assertEquals(45, TestLevelChapters.pick(45, full));
+        assertFalse(List.of(1).contains(TestLevelChapters.pick(1, Set.of(1))));
+    }
+}