fix(PlayerService): Handle nullable player objects + otherfixes

- Added a nullability check to the `playerProfile` variable in the `PlayerController` class.
- Previously, the `playerProfile` variable was of type `Player`, but it is now of type `Player?`.
- Modified the `GetPlayerAsync` and `UpdatePlayerRecordAsync` methods in the `PlayerService` class to handle nullable player objects.
- The return types of these methods have been changed from `Task<Player>` to `Task<Player?>`.
- If a player object is null, it will be handled appropriately and a null value will be returned.

WowsKarma.Api/Controllers/PlayerController.cs

@@ -54,7 +54,7 @@ public async Task<IActionResult> GetAccount(uint id, bool includeClanInfo = true
 			return BadRequest(new ArgumentException(null, nameof(id)));
 		}
 
-		Player playerProfile = await _playerService.GetPlayerAsync(id, false, includeClanInfo);
+		Player? playerProfile = await _playerService.GetPlayerAsync(id, false, includeClanInfo);
 
 		return playerProfile is null
 			? NotFound()

WowsKarma.Api/Services/PlayerService.cs

@@ -57,7 +57,10 @@ public async Task<IEnumerable<Player>> GetPlayersAsync(IEnumerable<uint> ids, bo
 
 		foreach (uint id in ids.AsParallel().WithCancellation(ct))
 		{
-			players.Add(await GetPlayerAsync(id, includeRelated, includeClanInfo, ct));
+			if (await GetPlayerAsync(id, includeRelated, includeClanInfo, ct) is { } player)
+			{
+				players.Add(player);
+			}
 		}
 
 		return players;
@@ -69,7 +72,7 @@ public async Task<IEnumerable<Player>> GetPlayersAsync(IEnumerable<uint> ids, bo
 	* Method no longer returns any tracked entity, resulting in dropped changes for EF Core
 	* Do not use unless readonly.
 	*/
-	public async Task<Player> GetPlayerAsync(uint accountId, bool includeRelated = false, bool includeClanInfo = false, CancellationToken ct = default)
+	public async Task<Player?> GetPlayerAsync(uint accountId, bool includeRelated = false, bool includeClanInfo = false, CancellationToken ct = default)
 	{
 		if (accountId is 0)
 		{
@@ -91,13 +94,19 @@ public async Task<Player> GetPlayerAsync(uint accountId, bool includeRelated = f
 		}
 
 
-		Player player = await dbPlayers.FirstOrDefaultAsync(p => p.Id == accountId, ct);
+		Player? player = await dbPlayers.FirstOrDefaultAsync(p => p.Id == accountId, ct);
 		bool updated = false;
 		bool insert = player is null;
 
 		if (insert || UpdateNeeded(player))
 		{
 			player = await UpdatePlayerRecordAsync(player, accountId);
+
+			if (player is null)
+			{
+				return null;
+			}
+
 			updated = true;
 
 			if (insert)
@@ -222,14 +231,15 @@ internal async Task<Player> UpdatePlayerClanStatusAsync(Player player, Cancellat
 		return player;
 	}
 
-	internal async Task<Player> UpdatePlayerRecordAsync(Player player, uint? accountId = null)
+	internal async Task<Player?> UpdatePlayerRecordAsync(Player? player, uint? accountId = null)
 	{
-		Player apiPlayer = (await _vortex.FetchAccountAsync(player?.Id ?? accountId ?? 0)).ToDbModel() ?? throw new ApplicationException("Account returned null.");
+		if ((await _vortex.FetchAccountAsync(player?.Id ?? accountId ?? 0))?.ToDbModel() is { } apiPlayer)
+		{
+			player = player is null
+				? _context.Players.Add(apiPlayer).Entity
+				: Player.MapFromApi(player, apiPlayer);
+		}
 
-		player = player is null 
-			? _context.Players.Add(apiPlayer).Entity 
-			: Player.MapFromApi(player, apiPlayer);
-
 		return player;
 	}