refactor: move common gameView functions to ViewUtils

src/main/java/millions/view/GameView.java

@@ -106,36 +106,7 @@ private Tab createStocksTab() {
             change -> change.getControlNewText().matches("-?\\d*") ? change : null));
     quantitySlider.setPrefWidth(200);
 
-    ownedSharesBox.setPrefWidth(260);
-    ownedSharesBox.setCellFactory(
-        comboBox ->
-            new ListCell<>() {
-              @Override
-              protected void updateItem(Share share, boolean empty) {
-                super.updateItem(share, empty);
-                if (empty || share == null) {
-                  setText(null);
-                  setStyle("");
-                } else {
-                  setText(formatOwnedShare(share));
-                  setStyle(getProfitStyle(share));
-                }
-              }
-            });
-    ownedSharesBox.setButtonCell(
-        new ListCell<>() {
-          @Override
-          protected void updateItem(Share share, boolean empty) {
-            super.updateItem(share, empty);
-            if (empty || share == null) {
-              setText("Select lot");
-              setStyle("");
-            } else {
-              setText(formatOwnedShare(share));
-              setStyle(getProfitStyle(share));
-            }
-          }
-        });
+    ViewUtils.configureOwnedSharesBox(ownedSharesBox);
 
     HBox sellBox = new HBox(8, sellButton, new VBox(4, new Label("Owned Shares"), ownedSharesBox));
 
@@ -178,7 +149,7 @@ protected void updateItem(Stock stock, boolean empty) {
                 if (empty || stock == null) {
                   setText(null);
                 } else {
-                  setText(formatStock(stock));
+                  setText(ViewUtils.formatStock(stock));
                 }
               }
             });
@@ -258,7 +229,7 @@ private void refreshQuantityControls(Stock stock) {
     }
 
     int maxBuyable = controller.getMaxBuyableQuantity(stock.getSymbol());
-    int current = clampQuantity(getQuantityValue(), Math.max(1, maxBuyable));
+    int current = ViewUtils.clampQuantity(getQuantityValue(), Math.max(1, maxBuyable));
 
     updatingQuantityControls = true;
     quantityField.setText(String.valueOf(current));
@@ -350,7 +321,7 @@ private void syncQuantityFromField(String newValue) {
     }
 
     updatingQuantityControls = true;
-    int clamped = clampQuantity(parseQuantity(newValue), getCurrentMaxBuyable());
+    int clamped = ViewUtils.clampQuantity(parseQuantity(newValue), getCurrentMaxBuyable());
     quantityField.setText(String.valueOf(clamped));
     quantitySlider.setValue(clamped);
     updatingQuantityControls = false;
@@ -362,7 +333,7 @@ private void syncQuantityFromSlider(int newValue) {
     }
 
     updatingQuantityControls = true;
-    int clamped = clampQuantity(newValue, getCurrentMaxBuyable());
+    int clamped = ViewUtils.clampQuantity(newValue, getCurrentMaxBuyable());
     quantityField.setText(String.valueOf(clamped));
     quantitySlider.setValue(clamped);
     updatingQuantityControls = false;
@@ -377,17 +348,6 @@ private int parseQuantity(String text) {
     }
   }
 
-  private int clampQuantity(int quantity, int maxBuyable) {
-    int upperBound = Math.max(1, maxBuyable);
-    if (quantity < 1) {
-      return 1;
-    }
-    if (quantity > upperBound) {
-      return upperBound;
-    }
-    return quantity;
-  }
-
   private int getCurrentMaxBuyable() {
     Stock selected = stocksList.getSelectionModel().getSelectedItem();
     if (selected == null) {
@@ -396,25 +356,8 @@ private int getCurrentMaxBuyable() {
     return Math.max(1, controller.getMaxBuyableQuantity(selected.getSymbol()));
   }
 
-  private String formatOwnedShare(Share share) {
-    BigDecimal profit = getShareProfit(share);
-    String sign = profit.compareTo(BigDecimal.ZERO) >= 0 ? "+" : "";
-    return share.getQuantity() + "|" + share.getPurchasePrice() + "|" + sign + profit;
-  }
-
-  private String getProfitStyle(Share share) {
-    return getShareProfit(share).compareTo(BigDecimal.ZERO) >= 0
-        ? "-fx-text-fill: green;"
-        : "-fx-text-fill: red;";
-  }
-
-  private BigDecimal getShareProfit(Share share) {
-    BigDecimal currentPrice = share.getStock().getSalesPrice();
-    return currentPrice.subtract(share.getPurchasePrice()).multiply(share.getQuantity());
-  }
-
   private String formatStock(Stock stock) {
-    return stock.getSymbol() + " - " + stock.getCompany() + " (" + stock.getSalesPrice() + ")";
+    return ViewUtils.formatStock(stock);
   }
 
   // Listener callbacks update the shared header and the stocks tab.

src/main/java/millions/view/ViewUtils.java

@@ -0,0 +1,77 @@
+package millions.view;
+
+import java.math.BigDecimal;
+import javafx.scene.control.ComboBox;
+import javafx.scene.control.ListCell;
+import millions.model.Share;
+import millions.model.Stock;
+
+/** Small utility helpers for view formatting and simple calculations. */
+public final class ViewUtils {
+
+  private ViewUtils() {}
+
+  public static void configureOwnedSharesBox(ComboBox<Share> comboBox) {
+    comboBox.setCellFactory(
+        box ->
+            new ListCell<>() {
+              @Override
+              protected void updateItem(Share share, boolean empty) {
+                super.updateItem(share, empty);
+                if (empty || share == null) {
+                  setText(null);
+                  setStyle("");
+                } else {
+                  setText(formatOwnedShare(share));
+                  setStyle(getProfitStyle(share));
+                }
+              }
+            });
+    comboBox.setButtonCell(
+        new ListCell<>() {
+          @Override
+          protected void updateItem(Share share, boolean empty) {
+            super.updateItem(share, empty);
+            if (empty || share == null) {
+              setText("Select lot");
+              setStyle("");
+            } else {
+              setText(formatOwnedShare(share));
+              setStyle(getProfitStyle(share));
+            }
+          }
+        });
+  }
+
+  public static String formatStock(Stock stock) {
+    return stock.getSymbol() + " - " + stock.getCompany() + " (" + stock.getSalesPrice() + ")";
+  }
+
+  public static String formatOwnedShare(Share share) {
+    BigDecimal profit = getShareProfit(share);
+    String sign = profit.compareTo(BigDecimal.ZERO) >= 0 ? "+" : "";
+    return share.getQuantity() + "|" + share.getPurchasePrice() + "|" + sign + profit;
+  }
+
+  public static String getProfitStyle(Share share) {
+    return getShareProfit(share).compareTo(BigDecimal.ZERO) >= 0
+        ? "-fx-text-fill: green;"
+        : "-fx-text-fill: red;";
+  }
+
+  public static BigDecimal getShareProfit(Share share) {
+    BigDecimal currentPrice = share.getStock().getSalesPrice();
+    return currentPrice.subtract(share.getPurchasePrice()).multiply(share.getQuantity());
+  }
+
+  public static int clampQuantity(int quantity, int maxBuyable) {
+    int upperBound = Math.max(1, maxBuyable);
+    if (quantity < 1) {
+      return 1;
+    }
+    if (quantity > upperBound) {
+      return upperBound;
+    }
+    return quantity;
+  }
+}