Move subcategory buttons to the right if the category has no entries

Mild positioning tweaks to category buttons to leave more space for
the description (they wasted quite a bit of space with advancement
locks disabled)

src/main/java/vazkii/patchouli/client/book/gui/GuiBookCategory.java

@@ -1,7 +1,11 @@
 package vazkii.patchouli.client.book.gui;
 
+import com.mojang.blaze3d.matrix.MatrixStack;
+
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.widget.TextFieldWidget;
 import net.minecraft.client.gui.widget.button.Button;
+import net.minecraft.client.resources.I18n;
 
 import vazkii.patchouli.client.book.BookCategory;
 import vazkii.patchouli.client.book.BookEntry;
@@ -12,7 +16,8 @@
 
 public class GuiBookCategory extends GuiBookEntryList {
 
-	BookCategory category;
+	private final BookCategory category;
+	private int subcategoryButtonCount;
 
 	public GuiBookCategory(Book book, BookCategory category) {
 		super(book, category.getName());
@@ -29,18 +34,36 @@ protected Collection<BookEntry> getEntries() {
 		return category.getEntries();
 	}
 
+	@Override
+	void drawForegroundElements(MatrixStack ms, int mouseX, int mouseY, float partialTicks) {
+		super.drawForegroundElements(ms, mouseX, mouseY, partialTicks);
+		if (getEntries().isEmpty() && subcategoryButtonCount <= 16 && subcategoryButtonCount > 0) {
+			int bottomSeparator = TOP_PADDING + 37 + 24 * ((subcategoryButtonCount - 1) / 4 + 1);
+			drawSeparator(ms, book, RIGHT_PAGE_X, bottomSeparator);
+		}
+	}
+
 	@Override
 	protected void addSubcategoryButtons() {
 		int i = 0;
 		List<BookCategory> categories = new ArrayList<>(book.contents.categories.values());
 		categories.removeIf(cat -> cat.getParentCategory() != category || cat.shouldHide());
 		Collections.sort(categories);
-
-		int baseY = TOP_PADDING + PAGE_HEIGHT - (categories.size() / 4) * 20 - (!book.advancementsEnabled() ? 46 : 68);
+		subcategoryButtonCount = categories.size();
+
+		int baseX, baseY;
+		boolean rightPageFree = getEntries().isEmpty();
+		if (rightPageFree) {
+			baseX = RIGHT_PAGE_X + 10;
+			baseY = TOP_PADDING + 25;
+		} else {
+			baseX = LEFT_PAGE_X + 10;
+			baseY = TOP_PADDING + PAGE_HEIGHT - (categories.size() / 4) * 20 - (!book.advancementsEnabled() ? 38 : 64);
+		}
 
 		for (BookCategory ocategory : categories) {
-			int x = LEFT_PAGE_X + 10 + (i % 4) * 24;
-			int y = baseY + (i / 4) * 20;
+			int x = baseX + (i % 4) * 24;
+			int y = baseY + (i / 4) * (rightPageFree ? 24 : 20);
 
 			Button button = new GuiButtonCategory(this, x, y, ocategory, this::handleButtonCategory);
 			addButton(button);
@@ -50,6 +73,33 @@ protected void addSubcategoryButtons() {
 		}
 	}
 
+	@Override
+	protected String getChapterListTitle() {
+		if (getEntries().isEmpty() && subcategoryButtonCount > 0) {
+			return I18n.format("patchouli.gui.lexicon.categories");
+		}
+		return super.getChapterListTitle();
+	}
+
+	@Override
+	protected String getNoEntryMessage() {
+		if (subcategoryButtonCount > 0) {
+			return "";
+		}
+		return super.getNoEntryMessage();
+	}
+
+	@Override
+	protected TextFieldWidget createSearchBar() {
+		TextFieldWidget widget = super.createSearchBar();
+		if (getEntries().isEmpty()) {
+			widget.active = false;
+			widget.setEnabled(false);
+			widget.setVisible(false);
+		}
+		return widget;
+	}
+
 	@Override
 	protected boolean doesEntryCountForProgress(BookEntry entry) {
 		return entry.getCategory() == category;

src/main/java/vazkii/patchouli/client/book/gui/GuiBookEntryList.java

@@ -51,16 +51,20 @@ public void init() {
 			Collections.sort(allEntries);
 		}
 
-		searchField = new TextFieldWidget(font, 160, 170, 90, 12, StringTextComponent.EMPTY);
-		searchField.setMaxStringLength(32);
-		searchField.setEnableBackgroundDrawing(false);
-		searchField.setCanLoseFocus(false);
-		searchField.setFocused2(true);
-
+		this.searchField = createSearchBar();
 		dependentButtons = new ArrayList<>();
 		buildEntryButtons();
 	}
 
+	protected TextFieldWidget createSearchBar() {
+		TextFieldWidget field = new TextFieldWidget(font, 160, 170, 90, 12, StringTextComponent.EMPTY);
+		field.setMaxStringLength(32);
+		field.setEnableBackgroundDrawing(false);
+		field.setCanLoseFocus(false);
+		field.setFocused2(true);
+		return field;
+	}
+
 	protected abstract String getDescriptionText();
 	protected abstract Collection<BookEntry> getEntries();
 
@@ -86,7 +90,7 @@ void drawForegroundElements(MatrixStack ms, int mouseX, int mouseY, float partia
 
 		if (spread == 0) {
 			drawCenteredStringNoShadow(ms, getTitle().func_241878_f(), LEFT_PAGE_X + PAGE_WIDTH / 2, TOP_PADDING, book.headerColor);
-			drawCenteredStringNoShadow(ms, I18n.format("patchouli.gui.lexicon.chapters"), RIGHT_PAGE_X + PAGE_WIDTH / 2, TOP_PADDING, book.headerColor);
+			drawCenteredStringNoShadow(ms, getChapterListTitle(), RIGHT_PAGE_X + PAGE_WIDTH / 2, TOP_PADDING, book.headerColor);
 
 			drawSeparator(ms, book, LEFT_PAGE_X, TOP_PADDING + 12);
 			drawSeparator(ms, book, RIGHT_PAGE_X, TOP_PADDING + 12);
@@ -113,11 +117,19 @@ void drawForegroundElements(MatrixStack ms, int mouseX, int mouseY, float partia
 				drawCenteredStringNoShadow(ms, I18n.format("patchouli.gui.lexicon.sad"), GuiBook.RIGHT_PAGE_X / 2 + GuiBook.PAGE_WIDTH / 4, 47, 0x999999);
 				ms.scale(0.5F, 0.5F, 0.5F);
 			} else {
-				drawCenteredStringNoShadow(ms, I18n.format("patchouli.gui.lexicon.no_entries"), GuiBook.RIGHT_PAGE_X + GuiBook.PAGE_WIDTH / 2, 80, 0x333333);
+				drawCenteredStringNoShadow(ms, getNoEntryMessage(), GuiBook.RIGHT_PAGE_X + GuiBook.PAGE_WIDTH / 2, 80, 0x333333);
 			}
 		}
 	}
 
+	protected String getChapterListTitle() {
+		return I18n.format("patchouli.gui.lexicon.chapters");
+	}
+
+	protected String getNoEntryMessage() {
+		return I18n.format("patchouli.gui.lexicon.no_entries");
+	}
+
 	@Override
 	public boolean mouseClickedScaled(double mouseX, double mouseY, int mouseButton) {
 		return text.click(mouseX, mouseY, mouseButton)

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories.json

@@ -1,5 +1,5 @@
 {
   "name": "Subcategories",
-  "description": "Tests for subcategories. This category just has a bunch of filler subcategories to see how button wrapping looks.",
+  "description": "Tests for subcategories. No entries here, so the subcategory buttons take their place.",
   "icon": "minecraft:writable_book"
 }

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/empty_subsubcategory.json

@@ -0,0 +1,6 @@
+{
+  "name": "Empty Sub-sub-category",
+  "parent": "patchouli:subcategories/normal_subcategory",
+  "description": "Empty sub-sub-category with no entries",
+  "icon": "minecraft:iron_ingot"
+}

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/empty_subsubcategory_1.json

@@ -0,0 +1,6 @@
+{
+  "name": "Empty Sub-sub-category 2",
+  "parent": "patchouli:subcategories/normal_subcategory",
+  "description": "Empty sub-sub-category with no entries",
+  "icon": "minecraft:gold_ingot"
+}

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/empty_subsubcategory_2.json

@@ -0,0 +1,6 @@
+{
+  "name": "Empty Sub-sub-category 3",
+  "parent": "patchouli:subcategories/normal_subcategory",
+  "description": "Empty sub-sub-category with no entries",
+  "icon": "minecraft:iron_pickaxe"
+}

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/empty_subsubcategory_3.json

@@ -0,0 +1,6 @@
+{
+  "name": "Empty Sub-sub-category 4",
+  "parent": "patchouli:subcategories/normal_subcategory",
+  "description": "Empty sub-sub-category with no entries",
+  "icon": "minecraft:iron_axe"
+}

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/empty_subsubcategory_4.json

@@ -0,0 +1,6 @@
+{
+  "name": "Empty Sub-sub-category 5",
+  "parent": "patchouli:subcategories/normal_subcategory",
+  "description": "Empty sub-sub-category with no entries",
+  "icon": "minecraft:iron_sword"
+}

src/main/resources/data/patchouli/patchouli_books/comprehensive_test_book/en_us/categories/subcategories/normal_subcategory.json

@@ -1,6 +1,6 @@
 {
   "name": "Normal Subcategory",
   "parent": "patchouli:subcategories",
-  "description": "Normal subcategory with some entries",
+  "description": "Normal subcategory with some entries and some empty subcategories to observe the behavior of category button wrapping.",
   "icon": "minecraft:cooked_chicken"
 }