Partial rewrite, missing:

- Correctly parsing incoming messages
- Sending the gamestate after relevant actions

Mau/Deck.cs

@@ -2,47 +2,86 @@
 
 public class Deck
 {
-    public List<Card> UnusedDeck = new();
-    public List<Card> UsedDeck = new();
+    private List<Card> _unusedDeck = new();
+    private List<Card> _usedDeck = new();
 
+    /**
+     * <summary>
+     * Creates a new deck instance with a new shuffled set of cards
+     * </summary>
+     */
     public Deck()
     {
         CreateSet();
         ShuffleDeck();
     }
+    
+    /**
+     * <summary>
+     * Adds the given card to the used cards deck.
+     * </summary>
+     * <param name="card">The card to add to the used cards deck.</param>
+     */
+    public void AddCardToUsedDeck(Card card)
+    {
+        _usedDeck.Add(card);
+    }
 
+    /**
+     * <summary>
+     * Adds the given list of cards to the used cards deck.
+     * </summary>
+     * <param name="cards">The list of cards to add to the used cards deck.</param>
+     */
+    public void AddCardsToUsedDeck(IEnumerable<Card> cards)
+    {
+        _usedDeck.AddRange(cards);
+    }
+
+    /**
+     * <summary>
+     * Creates a new deck of cards and adds them to the unused deck.
+     * </summary>
+     */
     private void CreateSet()
     {
         foreach (CardType cardType in Enum.GetValues(typeof(CardType)))
         {
             if (cardType == CardType.JOKER)
             {
-                UnusedDeck.Add(new Card(cardType, CardValue.RED));
-                UnusedDeck.Add(new Card(cardType, CardValue.BLACK));
+                _unusedDeck.Add(new Card(cardType, CardValue.RED));
+                _unusedDeck.Add(new Card(cardType, CardValue.BLACK));
                 continue;
             }
             foreach (CardValue cardValue in Enum.GetValues(typeof(CardValue)))
             {
                 if (cardValue is CardValue.RED or CardValue.BLACK) continue;
-                UnusedDeck.Add(new Card(cardType, cardValue));
+                _unusedDeck.Add(new Card(cardType, cardValue));
             }
         }
     }
     
-    public List<Card> GetUnusedDeck()
-    {
-        return UnusedDeck;
-    }
-    
+    /**
+     * <summary>
+     * Draws a card from the deck.
+     * If the deck is empty, the deck is reshuffled with <see cref="ReshuffleDeck"/>.
+     * </summary>
+     */
     public Card DrawCard()
     {
-        if (UnusedDeck.Count == 0) ReshuffleDeck();
-        var card = UnusedDeck[0];
-        UnusedDeck.RemoveAt(0);
+        if (_unusedDeck.Count == 0) ReshuffleDeck();
+        var card = _unusedDeck[0];
+        _unusedDeck.RemoveAt(0);
         return card;
     }
 
-    public List<Card> DrawCards(int amount)
+    /**
+     * <summary>
+     * Take a given amount of cards from the deck. This method calls <see cref="DrawCard"/> for each card.
+     * </summary>
+     * <param name="amount">The amount of cards to draw from the deck.</param>
+     */
+    public IEnumerable<Card> DrawCards(int amount)
     {
         var cards = new List<Card>();
         for (var i = 0; i < amount; i++)
@@ -51,18 +90,19 @@ public class Deck
         }
         return cards;
     }
-    
-    public void AddCardToUsedDeck(Card card)
-    {
-        UsedDeck.Add(card);
-    }
 
+    /**
+     * <summary>
+     * Moves all the used cards back to the unused deck and shuffles it.
+     * If there are no cards to reshuffle, a new set of cards is created and shuffled.
+     * </summary>
+     */
     private void ReshuffleDeck()
     {
-        UnusedDeck.AddRange(UsedDeck);
-        UsedDeck.Clear();
+        _unusedDeck.AddRange(_usedDeck);
+        _usedDeck.Clear();
 
-        if (UnusedDeck.Count == 0)
+        if (_unusedDeck.Count == 0)
         {
             CreateSet();
         }
@@ -70,8 +110,13 @@ public class Deck
         ShuffleDeck();
     }
 
+    /**
+     * <summary>
+     * Shuffles all the cards in the deck using the Fisher-Yates algorithm.
+     * </summary>
+     */
     private void ShuffleDeck()
     {
-        UnusedDeck = UnusedDeck.OrderBy(x => Guid.NewGuid()).ToList();
+        _unusedDeck = _unusedDeck.OrderBy(x => Guid.NewGuid()).ToList();
     }
 }