Feat: Refactored Exchange, testing

Refactored Exchange, fixed semantic bugs, centralized logic, and made integerproperty read only for safety and encapsulation

src/main/java/edu/ntnu/idi/idatt2003/g40/mappe/engine/Exchange.java

@@ -4,7 +4,11 @@
 import edu.ntnu.idi.idatt2003.g40.mappe.model.Share;
 import edu.ntnu.idi.idatt2003.g40.mappe.model.Stock;
 import edu.ntnu.idi.idatt2003.g40.mappe.model.Transaction;
-import edu.ntnu.idi.idatt2003.g40.mappe.service.*;
+import edu.ntnu.idi.idatt2003.g40.mappe.service.PurchaseCalculator;
+import edu.ntnu.idi.idatt2003.g40.mappe.service.SaleCalculator;
+import edu.ntnu.idi.idatt2003.g40.mappe.service.TransactionCalculator;
+import edu.ntnu.idi.idatt2003.g40.mappe.service.TransactionFactory;
+import edu.ntnu.idi.idatt2003.g40.mappe.service.TransactionType;
 import edu.ntnu.idi.idatt2003.g40.mappe.utils.Validator;
 import java.math.BigDecimal;
 import java.util.ArrayList;
@@ -13,7 +17,7 @@
 import java.util.Map;
 import java.util.Random;
 import javafx.beans.property.IntegerProperty;
-import javafx.beans.property.SimpleIntegerProperty;
+import javafx.beans.property.ReadOnlyIntegerWrapper;
 
 /**
  * Represents a stock exchange where stocks can be traded.
@@ -40,7 +44,7 @@ public final class Exchange {
   /**
    * Current week (set to 1 in constructor).
    * */
-  private final IntegerProperty week = new SimpleIntegerProperty(1);
+  private final ReadOnlyIntegerWrapper week = new ReadOnlyIntegerWrapper(1);
 
   /**
    * Map of {@link Stock} objects. Key is stock symbol. Value is stock.
@@ -120,10 +124,12 @@ public boolean hasStock(final String symbol) {
    *
    * @return {@link Stock}  element gotten.
    *
-   * @throws IllegalArgumentException if symbol is invalid.
+   * @throws IllegalArgumentException if symbol is invalid or not in exchange.
    * */
-  public Stock getStock(final String symbol) throws IllegalArgumentException {
-    if (!Validator.VALID_STOCK_SYMBOL.isValid(symbol)) {
+  public Stock getStock(final String symbol)
+          throws IllegalArgumentException {
+    if (!Validator.VALID_STOCK_SYMBOL.isValid(symbol)
+        || !stockMap.containsKey(symbol)) {
       throw new IllegalArgumentException(
               Validator.VALID_STOCK_SYMBOL.getErrorMessage());
     }
@@ -164,10 +170,12 @@ public List<Stock> findStocks(final String searchTerm) {
   public Transaction buy(final String symbol,
                          final BigDecimal quantity,
                          final Player player) throws IllegalArgumentException {
-    if (!Validator.VALID_STOCK_SYMBOL.isValid(symbol) || player == null) {
+    if (!Validator.VALID_STOCK_SYMBOL.isValid(symbol)
+        || quantity == null
+        || player == null) {
       throw new IllegalArgumentException("Invalid purchase!");
     }
-    Stock stock = stockMap.get(symbol);
+    Stock stock = getStock(symbol);
     Share share = new Share(stock, quantity, stock.getSalesPrice());
     TransactionCalculator calculator = new PurchaseCalculator(share);
     Transaction purchase = TransactionFactory.createTransaction(
@@ -212,10 +220,12 @@ TransactionType.SALE, share, getWeek(), calculator
    * @param stockSymbol the stock to sell shares in.
    * @param player      the player buying stock.
    *
-   * @return List of transactions commited to sell the shares.
+   * @return            List of transactions commited to sell the shares.
    *
    * @throws IllegalArgumentException if any parameter is null,
-   *                                  or if player does not have enough shares.
+   *                                  or if player does not have enough shares,
+   *                                  or if player does not own any shares
+   *                                  of the given stock.
    * */
   public List<Transaction> sell(BigDecimal amount,
                                 final String stockSymbol,
@@ -225,41 +235,50 @@ public List<Transaction> sell(BigDecimal amount,
         || player == null
         || !Validator.VALID_STOCK_SYMBOL.isValid(stockSymbol)) {
       throw new IllegalArgumentException("Invalid sell!");
-    } else {
+    }
 
-      List<Share> sharesOfStock = player.getPortfolio().getShares().stream()
-              .filter(s -> s.getStock().getSymbol().equals(stockSymbol))
-              .toList();
+    // Get all shares the player owns of the stock given in the parameter.
+    List<Share> sharesOfStock = player.getPortfolio().getShares().stream()
+            .filter(s -> s.getStock().getSymbol().equals(stockSymbol))
+            .toList();
 
-      BigDecimal totalOwned = player.getPortfolio()
-              .getTotalSharesBySymbol(stockSymbol);
+    // Throws error if player does not own any shares of the given stock.
+    if (sharesOfStock.isEmpty()) {
+      throw new IllegalArgumentException("Player does not own"
+              + " any shares of this stock!");
+    }
 
-      if (amount.compareTo(totalOwned) > 0) {
-        amount = totalOwned;
-      }
-      ArrayList<Transaction> transactions = new ArrayList<>();
-      BigDecimal remainingToSell = amount;
+    // Gets the total quantity amount of shares owned of given stock.
+    BigDecimal totalOwned = player.getPortfolio()
+            .getTotalSharesBySymbol(stockSymbol);
+
+    // If amount wanted to sell is greater than total owned,
+    // sells entire collection.
+    if (amount.compareTo(totalOwned) > 0) {
+      amount = totalOwned;
+    }
+    ArrayList<Transaction> transactions = new ArrayList<>();
+    BigDecimal remainingToSell = amount;
 
-      for (Share share : sharesOfStock) {
-        if (remainingToSell.compareTo(BigDecimal.ZERO) <= 0) {
-          break;
-        }
+    // For every share owned, sells if the quantity is less than
+    // or equal to the remaining amount of shares to sell.
+    // Splits share if the remaining amount to sell is less than share quantity.
+    for (Share share : sharesOfStock) {
 
-        BigDecimal shareQty = share.getQuantity();
+      BigDecimal shareQty = share.getQuantity();
 
-        if (shareQty.compareTo(remainingToSell) <= 0) {
-          remainingToSell = remainingToSell.subtract(shareQty);
-          transactions.add(sell(share, player));
-        } else {
-          Share newShare = player.getPortfolio().splitShare(
-                  share, remainingToSell
-          );
-          remainingToSell = BigDecimal.ZERO;
-          transactions.add(sell(newShare, player));
-        }
+      if (shareQty.compareTo(remainingToSell) <= 0) {
+        remainingToSell = remainingToSell.subtract(shareQty);
+        transactions.add(sell(share, player));
+      } else {
+        Share newShare = player.getPortfolio().splitShare(
+                share, remainingToSell
+        );
+        transactions.add(sell(newShare, player));
+        break;
       }
-      return transactions;
     }
+    return transactions;
   }
 
   /**
@@ -275,12 +294,13 @@ public void advance() {
     for (Stock stock : stockMap.values()) {
       BigDecimal currentPrice = stock.getSalesPrice();
 
-      double change = (
-              (random.nextDouble() * 0.10) - 0.05) + stock.getFortune();
+      BigDecimal change = BigDecimal.valueOf(random.nextDouble() * 0.10 - 0.05)
+              .add(BigDecimal.valueOf(stock.getFortune()));
       stock.setFortune(0);
-      BigDecimal factor = BigDecimal.valueOf(1 + change);
+      BigDecimal factor = BigDecimal.ONE.add(change);
 
-      BigDecimal newPrice = currentPrice.multiply(factor);
+      BigDecimal newPrice = currentPrice.multiply(factor)
+              .setScale(2, java.math.RoundingMode.HALF_UP);
       stock.addNewSalesPrice(newPrice);
     }
     week.set(week.get() + 1);