Add a method for adding chips

src/js/Game.js

@@ -111,13 +111,41 @@ export class Game
 
                 field.onclick = () =>
                 {
-                    this.board[y][x] = this.state.currentPlayer;
+                    if (this.addChip(x, y))
+                    {
                         this.state.turnCount++;
                         this.draw();
+                    }
                 };
 
                 board.appendChild(field);
             }
         }
     }
+
+    /**
+     * Adds a chip to the board indicated by the {@link x `x`} and the {@link y `y`} coordinate.
+     *
+     * @param {number} x
+     * The x coordinate to add the chip to.
+     *
+     * @param {number} y
+     * The y coordinate to add the chip to.
+     *
+     * @returns {boolean}
+     * A value indicating whether the chip could be added.
+     */
+    addChip(x, y)
+    {
+        for (let i = Game.#height - 1; i >= 0; i--)
+        {
+            if (this.board[i][x] === "")
+            {
+                this.board[i][x] = this.state.currentPlayer;
+                return true;
+            }
+        }
+
+        return false;
+    }
 }