Refactor gem swap logic to handle invalid moves and animations

- Add proper validation for null gems during swap operations
- Implement swap-back animation for invalid moves (no matches)
- Restructure swap flow to emit animation states before match detection
- Add move limit validation before processing matches
- Improve error handling and logging for edge cases

lib/bloc/game_bloc.dart

@@ -279,13 +279,16 @@ class GameBloc extends Bloc<GameEvent, GameState> {
           currentState.grid, event.row1, event.col1, event.row2, event.col2)) {
         return;
       }
-      final newGrid = currentState.grid.clone();
+      GameGrid newGrid = currentState.grid.clone();
 
       // Perform swap
       final gem1 = newGrid.getGem(event.row1, event.col1);
       final gem2 = newGrid.getGem(event.row2, event.col2);
 
-      if (gem1 != null && gem2 != null) {
+      if (gem1 == null || gem2 == null) {
+        print("Gem1 or Gem2 is null, that should not be so");
+        return;
+      }
       newGrid.setGem(event.row1, event.col1,
           gem2.copyWith(row: event.row1, col: event.col1));
       newGrid.setGem(event.row2, event.col2,
@@ -343,6 +346,7 @@ class GameBloc extends Bloc<GameEvent, GameState> {
         add(ProcessMatches());
       } else {
         // Revert swap if no matches
+        newGrid = newGrid.clone();
         newGrid.setGem(event.row1, event.col1, gem1);
         newGrid.setGem(event.row2, event.col2, gem2);
         var done = Completer();
@@ -358,8 +362,19 @@ class GameBloc extends Bloc<GameEvent, GameState> {
           gem2: gem1,
           done: done.complete,
         ));
-        }
-        // Wait for swap animation
+        // Wait for swap-back animation
+        await done.future;
+
+        done = Completer();
+        emit(GameLevelIdle(
+          grid: newGrid,
+          level: currentState.level,
+          score: currentState.score,
+          moves: currentState.moves,
+          timeElapsed: currentState.timeElapsed,
+          gemsCleared: currentState.gemsCleared,
+          done: done.complete,
+        ));
         await done.future;
       }
     }

lib/game/components/gem_component.dart

@@ -55,7 +55,7 @@ class GemComponent extends RectangleComponent with TapCallbacks {
     parent?.add(explosion);
 
     // Animate gem destruction
-    PhysicsSystem.animateMatch(this);
+    await PhysicsSystem.animateMatch(this);
 
     // Remove after animation
     await Future.delayed(

lib/game/components/particle_system.dart

@@ -9,11 +9,12 @@ class ParticleSystem {
     return ParticleSystemComponent(
       priority: 1,
       particle: Particle.generate(
-        count: 15,
+        count: 50,
         lifespan: 1.0,
         generator: (i) => AcceleratedParticle(
-          acceleration: Vector2(0, 200),
-          speed: Vector2.random(Random()) * 100,
+          acceleration:
+              (Vector2.random(Random()) - Vector2.random(Random())) * 300,
+          speed: (Vector2.random(Random()) - Vector2.random(Random())) * 500,
           position: Vector2.zero(),
           child: CircleParticle(
             radius: Random().nextDouble() * 3 + 2,

lib/game/match_three_game.dart

@@ -1,6 +1,7 @@
 import 'dart:ui';
 
 import 'package:flame/game.dart';
+import 'package:match_three/game/components/gem_component.dart';
 import 'package:match_three/game/systems/match_detector.dart';
 import 'components/grid_component.dart';
 import 'components/background_component.dart';
@@ -51,23 +52,32 @@ class MatchThreeGame extends FlameGame {
       selectedGem = gem;
       return;
     }
-    if (MatchDetector.isValidSwap(gridComponent!.gameGrid, selectedGem!.row,
-        selectedGem!.col, gem.row, gem.col)) {
+    var theGem = selectedGem;
+    selectedGem = null;
+    if (MatchDetector.isValidSwap(
+        gridComponent!.gameGrid, theGem!.row, theGem.col, gem.row, gem.col)) {
       // Attempt swap
       print(
-          ")) Valid swapping ${selectedGem!.row}, ${selectedGem!.col} with ${gem.row}, ${gem.col}");
+          ")) Valid swapping ${theGem.row}, ${theGem.col} with ${gem.row}, ${gem.col}");
 
       gameBloc.add(SwapGems(
-        selectedGem!.row,
-        selectedGem!.col,
+        theGem.row,
+        theGem.col,
         gem.row,
         gem.col,
       ));
     } else {
       print(
-          "(( Invalid swapping ${selectedGem!.row}, ${selectedGem!.col} with ${gem.row}, ${gem.col}");
+          "(( Invalid swapping ${theGem.row}, ${theGem.col} with ${gem.row}, ${gem.col}");
+    }
+    if (gridComponent == null) {
+      return;
+    }
+    for (var comp in gridComponent!.children) {
+      if (comp is GemComponent && comp.gem != gem) {
+        comp.isSelected = false;
+      }
     }
-    selectedGem = null;
   }
 
   void setGameBloc(GameBloc bloc) {

lib/game/models/grid.dart

@@ -45,7 +45,7 @@ class GameGrid {
     return row >= 0 && row < height && col >= 0 && col < width;
   }
 
-  clone() {
+  GameGrid clone() {
     final clonedGrid = GameGrid(width: width, height: height);
     for (int row = 0; row < _grid.length; row++) {
       for (int col = 0; col < _grid[row].length; col++) {

lib/game/systems/match_detector.dart

@@ -11,7 +11,7 @@ class MatchDetector {
     for (int row = 0; row < grid.height; row++) {
       for (int col = 0; col < grid.width; col++) {
         final gem = grid.getGem(row, col);
-        if (gem == null || matches.contains(gem)) {
+        if (gem == null) {
           continue;
         }
         currentMatch.add(gem);

lib/game/systems/physics_system.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:flame/components.dart';
 import 'package:flame/effects.dart';
 import 'package:flutter/material.dart';
@@ -38,17 +40,23 @@ class PhysicsSystem {
     await Future.delayed(Duration(milliseconds: (fallTime * 1000).toInt()));
   }
 
-  static void animateMatch(GemComponent gem) {
+  static Future<void> animateMatch(GemComponent gem) async {
+    final scaleDone = Completer();
+    final opacityDone = Completer();
     // Scale down and fade out
     gem.add(ScaleEffect.to(
       Vector2.zero(),
       EffectController(duration: GameConstants.matchDuration),
+      onComplete: () => scaleDone.complete(),
     ));
 
     gem.add(OpacityEffect.to(
       0.0,
       EffectController(duration: GameConstants.matchDuration),
+      onComplete: () => opacityDone.complete(),
     ));
+
+    await Future.wait([scaleDone.future, opacityDone.future]);
   }
 
   static void animatePop(GemComponent gem) {

lib/screens/game_screen.dart

@@ -19,6 +19,7 @@ class GameScreen extends StatefulWidget {
 
 class _GameScreenState extends State<GameScreen> {
   late MatchThreeGame game;
+  final bool isDebug = true;
 
   @override
   void initState() {
@@ -75,6 +76,16 @@ class _GameScreenState extends State<GameScreen> {
                             ),
                           ),
                           const SizedBox(height: 4),
+                          if (isDebug)
+                            Text(
+                              'State: ${state.runtimeType}',
+                              style: const TextStyle(
+                                color: Colors.white,
+                                fontSize: 18,
+                                fontWeight: FontWeight.bold,
+                              ),
+                            ),
+                          const SizedBox(height: 4),
                           Text(
                             'Score: ${state.score}',
                             style: const TextStyle(