Added updatePlayersFromGame(), added docs & tests

lib/data/dao/player_game_dao.dart

@@ -79,4 +79,50 @@ class PlayerGameDao extends DatabaseAccessor<AppDatabase>
     final rowsAffected = await query.go();
     return rowsAffected > 0;
   }
+
+  /// Updates the players associated with a game based on the provided
+  /// [newPlayer] list. It adds new players and removes players that are no
+  /// longer associated with the game.
+  Future<void> updatePlayersFromGame({
+    required String gameId,
+    required List<Player> newPlayer,
+  }) async {
+    final currentPlayers = await getPlayersOfGame(gameId: gameId);
+    // Create sets of player IDs for easy comparison
+    final currentPlayerIds = currentPlayers?.map((p) => p.id).toSet() ?? {};
+    final newPlayerIdsSet = newPlayer.map((p) => p.id).toSet();
+
+    // Determine players to add and remove
+    final playersToAdd = newPlayerIdsSet.difference(currentPlayerIds);
+    final playersToRemove = currentPlayerIds.difference(newPlayerIdsSet);
+
+    db.transaction(() async {
+      // Remove old players
+      if (playersToRemove.isNotEmpty) {
+        await (delete(playerGameTable)..where(
+              (pg) =>
+                  pg.gameId.equals(gameId) &
+                  pg.playerId.isIn(playersToRemove.toList()),
+            ))
+            .go();
+      }
+
+      // Add new players
+      if (playersToAdd.isNotEmpty) {
+        final inserts = playersToAdd
+            .map(
+              (id) =>
+                  PlayerGameTableCompanion.insert(playerId: id, gameId: gameId),
+            )
+            .toList();
+        await Future.wait(
+          inserts.map(
+            (c) => into(
+              playerGameTable,
+            ).insert(c, mode: InsertMode.insertOrReplace),
+          ),
+        );
+      }
+    });
+  }
 }

test/db_tests/player_game_test.dart

@@ -136,5 +136,49 @@ void main() {
         expect(players[i].createdAt, testGameOnlyPlayers.players![i].createdAt);
       }
     });
+
+    test('Updating the games players works coreclty', () async {
+      await database.gameDao.addGame(game: testGameOnlyPlayers);
+
+      final newPlayers = [testPlayer1, testPlayer2, testPlayer4];
+      await database.playerDao.addPlayers(players: newPlayers);
+
+      // First, remove all existing players
+      final existingPlayers = await database.playerGameDao.getPlayersOfGame(
+        gameId: testGameOnlyPlayers.id,
+      );
+
+      print('existingPlayers: $existingPlayers');
+      if (existingPlayers == null || existingPlayers.isEmpty) {
+        fail('Existing players should not be null or empty');
+      }
+
+      await database.playerGameDao.updatePlayersFromGame(
+        gameId: testGameOnlyPlayers.id,
+        newPlayer: newPlayers,
+      );
+
+      final updatedPlayers = await database.playerGameDao.getPlayersOfGame(
+        gameId: testGameOnlyPlayers.id,
+      );
+
+      if (updatedPlayers == null) {
+        fail('Updated players should not be null');
+      }
+
+      expect(updatedPlayers.length, newPlayers.length);
+
+      /// Create a map of new players for easy lookup
+      final testPlayers = {for (var p in newPlayers) p.id: p};
+
+      /// Verify each updated player matches the new players
+      for (final player in updatedPlayers) {
+        final testPlayer = testPlayers[player.id]!;
+
+        expect(player.id, testPlayer.id);
+        expect(player.name, testPlayer.name);
+        expect(player.createdAt, testPlayer.createdAt);
+      }
+    });
   });
 }