feat(ui/button): implement more events & simulators

This commit implements events onHoverEnter/onHoverExit.

Simulators have .click() to simulate click, .hoverEnter()/.hoverExit() and so on.

app/src/main/java/org/vibecoders/moongazer/scenes/MainMenu.java

@@ -10,9 +10,12 @@ import org.vibecoders.moongazer.managers.Assets;
 import org.vibecoders.moongazer.ui.UITextButton;
 
 import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.Input;
 import com.badlogic.gdx.files.FileHandle;
 import com.badlogic.gdx.graphics.Texture;
 import com.badlogic.gdx.graphics.g2d.SpriteBatch;
+import com.badlogic.gdx.scenes.scene2d.InputEvent;
+import com.badlogic.gdx.scenes.scene2d.InputListener;
 import com.badlogic.gdx.video.VideoPlayer;
 import com.badlogic.gdx.video.VideoPlayerCreator;
 
@@ -20,8 +23,10 @@ public class MainMenu extends Scene {
     private VideoPlayer videoPlayer;
     private FileHandle videoFileHandle;
     private Texture titleTexture;
+    private UITextButton[] buttons;
     private float titleY, titleX, titleWidth, titleHeight;
     private boolean videoPrepared = false;
+    private int currentChoice = -1;
 
     public MainMenu(Game game) {
         super(game);
@@ -55,6 +60,7 @@ public class MainMenu extends Scene {
         UITextButton loadButton = new UITextButton("Load", font);
         UITextButton settingsButton = new UITextButton("Settings", font);
         UITextButton exitButton = new UITextButton("Exit", font);
+        buttons = new UITextButton[] { playButton, loadButton, settingsButton, exitButton };
 
         int buttonWidth = 300;
         int buttonHeight = 80;
@@ -77,6 +83,7 @@ public class MainMenu extends Scene {
         exitButton.setSize(buttonWidth, buttonHeight);
         exitButton.setPosition(centerX, startY - spacing * 3);
 
+        // Mouse click handlers
         playButton.onClick(() -> log.debug("Play clicked"));
         loadButton.onClick(() -> log.debug("Load clicked"));
         settingsButton.onClick(() -> {
@@ -95,9 +102,65 @@ public class MainMenu extends Scene {
         root.addActor(settingsButton.getActor());
         root.addActor(exitButton.getActor());
 
+        // Keyboard navigation handling
+        initKeyboardHandling();
         game.stage.addActor(root);
     }
 
+    private void initKeyboardHandling() {
+        for (int i = 0; i < buttons.length; i++) {
+            final int index = i;
+            buttons[i].onHoverEnter(() -> {
+                log.trace("Button hover enter: {}", index);
+                if (currentChoice != index) {
+                    if (currentChoice != -1) {
+                        buttons[currentChoice].hoverExit();
+                    }
+                    currentChoice = index;
+                }
+            });
+            buttons[i].onHoverExit(() -> {
+                if (currentChoice == index) {
+                    currentChoice = -1;
+                }
+            });
+        }
+
+        root.addListener(new InputListener() {
+            @Override
+            public boolean keyDown(InputEvent event, int keycode) {
+                log.trace("Key pressed: {}", keycode);
+                switch (keycode) {
+                    case Input.Keys.UP:
+                        currentChoice = (currentChoice - 1 + 4) % 4;
+                        break;
+                    case Input.Keys.DOWN:
+                        currentChoice = (currentChoice + 1) % 4;
+                        break;
+                    case Input.Keys.RIGHT:
+                    case Input.Keys.ENTER:
+                        if (currentChoice != -1) {
+                            buttons[currentChoice].click();
+                        }
+                        break;
+                    default:
+                        break;
+                }
+                if (currentChoice != -1) {
+                    log.trace("Current choice: {}", currentChoice);
+                    for (int i = 0; i < buttons.length; i++) {
+                        if (i == currentChoice) {
+                            buttons[i].hoverEnter();
+                        } else {
+                            buttons[i].hoverExit();
+                        }
+                    }
+                }
+                return true;
+            }
+        });
+    }
+
     private void startVideoOnce() {
         if (videoPlayer == null || videoPrepared)
             return;

app/src/main/java/org/vibecoders/moongazer/ui/UIButton.java

@@ -1,12 +1,15 @@
 package org.vibecoders.moongazer.ui;
 
+import com.badlogic.gdx.Input;
 import com.badlogic.gdx.scenes.scene2d.Actor;
 import com.badlogic.gdx.scenes.scene2d.EventListener;
 import com.badlogic.gdx.scenes.scene2d.ui.Button;
+import com.badlogic.gdx.scenes.scene2d.InputEvent;
+import com.badlogic.gdx.scenes.scene2d.utils.ClickListener;
 
 public abstract class UIButton {
-    protected Actor actor;
+    public Actor actor;
-    protected Button button;
+    public Button button;
 
     public Actor getActor() {
         return actor;
@@ -24,12 +27,65 @@ public abstract class UIButton {
         actor.addListener(eventListener);
     }
 
+    public void click() {
+        // Thx ChatGPT
+        InputEvent down = new InputEvent();
+        down.setType(InputEvent.Type.touchDown);
+        down.setButton(Input.Buttons.LEFT);
+        down.setStageX(button.getX());
+        down.setStageY(button.getY());
+        button.fire(down);
+
+        InputEvent up = new InputEvent();
+        up.setType(InputEvent.Type.touchUp);
+        up.setButton(Input.Buttons.LEFT);
+        up.setStageX(button.getX());
+        up.setStageY(button.getY());
+        button.fire(up);
+    }
+
+    public void hoverEnter() {
+        InputEvent e = new InputEvent();
+        e.setType(InputEvent.Type.enter);
+        e.setPointer(-1);
+        button.fire(e);
+    }
+
+    public void hoverExit() {
+        InputEvent e = new InputEvent();
+        e.setType(InputEvent.Type.exit);
+        e.setPointer(-1);
+        button.fire(e);
+    }
+
     public void onClick(Runnable action) {
-        button.addListener(new com.badlogic.gdx.scenes.scene2d.utils.ClickListener() {
+        button.addListener(new ClickListener() {
             @Override
-            public void clicked(com.badlogic.gdx.scenes.scene2d.InputEvent event, float x, float y) {
+            public void clicked(InputEvent event, float x, float y) {
                 action.run();
             }
         });
     }
+
+    public void onHoverEnter(Runnable action) {
+        button.addListener(new ClickListener() {
+            @Override
+            public void enter(InputEvent event, float x, float y, int pointer, Actor fromActor) {
+                if (pointer == -1) {
+                    action.run();
+                }
+            }
+        });
+    }
+
+    public void onHoverExit(Runnable action) {
+        button.addListener(new ClickListener() {
+            @Override
+            public void exit(InputEvent event, float x, float y, int pointer, Actor toActor) {
+                if (pointer == -1) {
+                    action.run();
+                }
+            }
+        });
+    }
 }