feat: add elapsed time, fix bugs

src/main/java/eu/midnightdust/yaytris/Tetris.java

@@ -6,6 +6,7 @@ import eu.midnightdust.yaytris.ui.TetrisUI;
 import eu.midnightdust.yaytris.util.SoundUtil;
 
 import javax.swing.*;
+import java.time.LocalTime;
 import java.util.Random;
 import java.util.Timer;
 import java.util.TimerTask;
@@ -16,6 +17,7 @@ public class Tetris {
     private static Timer timer;
     private static TetrisUI ui;
     private static TimerTask gravityTask;
+    private static LocalTime startTime;
 
     public static void main(String[] args) {
         try {
@@ -42,10 +44,12 @@ public class Tetris {
     public static void startGame() {
         SoundUtil.playMusic("/music/theme.wav", true);
         space.spawnTetromino();
+        startTime = LocalTime.now();
         gravityTask = new TimerTask() {
             @Override
             public void run() {
                 if (space.getCurrentTetromino() != null) {
+                    updateTime();
                     space.getCurrentTetromino().fall();
                     ui.getGamePanel().repaint();
                 }
@@ -65,4 +69,7 @@ public class Tetris {
     public static void updateScore(int score) {
         if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).updateScore(score);
     }
+    public static void updateTime() {
+        if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).updateTime(startTime);
+    }
 }