scrollable navbar, group descriptions, auto-scroll descriptions

1 files changed, 79 insertions, 0 deletions

diff --git a/common/src/main/java/dev/isxander/yacl/gui/ScrollableNavigationBar.java b/common/src/main/java/dev/isxander/yacl/gui/ScrollableNavigationBar.java
new file mode 100644
index 0000000..e2d9ab8
--- /dev/null
+++ b/common/src/main/java/dev/isxander/yacl/gui/ScrollableNavigationBar.java
@@ -0,0 +1,79 @@
+package dev.isxander.yacl.gui;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.Font;
+import net.minecraft.client.gui.components.AbstractWidget;
+import net.minecraft.client.gui.components.TabButton;
+import net.minecraft.client.gui.components.events.GuiEventListener;
+import net.minecraft.client.gui.components.tabs.Tab;
+import net.minecraft.client.gui.components.tabs.TabManager;
+import net.minecraft.client.gui.components.tabs.TabNavigationBar;
+import net.minecraft.util.Mth;
+import org.jetbrains.annotations.Nullable;
+
+public class ScrollableNavigationBar extends TabNavigationBar {
+    private static final int NAVBAR_MARGIN = 28;
+
+    private static final Font font = Minecraft.getInstance().font;
+
+    private int scrollOffset;
+    private int maxScrollOffset;
+
+    public ScrollableNavigationBar(int i, TabManager tabManager, Iterable<Tab> iterable) {
+        super(i, tabManager, iterable);
+    }
+
+    @Override
+    public void arrangeElements() {
+        int noScrollWidth = this.width - NAVBAR_MARGIN*2;
+        int minimumSize = tabButtons.stream()
+                .map(AbstractWidget::getMessage)
+                .mapToInt(label -> font.width(label) + 3)
+                .min().orElse(0);
+        int singleTabWidth = Math.max(noScrollWidth / Math.min(this.tabButtons.size(), 3), minimumSize);
+        for (TabButton tabButton : this.tabButtons) {
+            tabButton.setWidth(singleTabWidth);
+        }
+
+        this.layout.arrangeElements();
+        this.layout.setY(0);
+        this.scrollOffset = 0;
+
+        int allTabsWidth = singleTabWidth * this.tabButtons.size();
+        this.layout.setX(Math.max((this.width - allTabsWidth) / 2, NAVBAR_MARGIN));
+        this.maxScrollOffset = Math.max(0, allTabsWidth - noScrollWidth);
+    }
+
+    @Override
+    public boolean mouseScrolled(double mouseX, double mouseY, double amount) {
+        this.setScrollOffset(this.scrollOffset - (int)(amount*10));
+        return true;
+    }
+
+    @Override
+    public boolean isMouseOver(double mouseX, double mouseY) {
+        return mouseY <= 24;
+    }
+
+    public void setScrollOffset(int scrollOffset) {
+        layout.setX(layout.getX() + this.scrollOffset);
+        this.scrollOffset = Mth.clamp(scrollOffset, 0, maxScrollOffset);
+        layout.setX(layout.getX() - this.scrollOffset);
+    }
+
+    @Override
+    public void setFocused(@Nullable GuiEventListener child) {
+        super.setFocused(child);
+        if (child instanceof TabButton tabButton) {
+            this.ensureVisible(tabButton);
+        }
+    }
+
+    protected void ensureVisible(TabButton tabButton) {
+        if (tabButton.getX() < NAVBAR_MARGIN) {
+            this.setScrollOffset(this.scrollOffset - (NAVBAR_MARGIN - tabButton.getX()));
+        } else if (tabButton.getX() + tabButton.getWidth() > this.width - NAVBAR_MARGIN) {
+            this.setScrollOffset(this.scrollOffset + (tabButton.getX() + tabButton.getWidth() - (this.width - NAVBAR_MARGIN)));
+        }
+    }
+}