feat: Enhance loan processing with validation checks and service integration

MartinTCode · MartinTCode · commit 270c69868bb3 · 2025-06-01T19:53:48.000+02:00
diff --git a/src/main/java/com/javafullstacklibrary/frontend/borrowerControllers/LoanReceiptBorrowerController.java b/src/main/java/com/javafullstacklibrary/frontend/borrowerControllers/LoanReceiptBorrowerController.java
@@ -9,16 +9,10 @@
 
 import com.javafullstacklibrary.model.Item;
 import com.javafullstacklibrary.model.ItemCopy;
-import com.javafullstacklibrary.model.LibraryUser;
 import com.javafullstacklibrary.utils.MenuNavigationHelper;
 import com.javafullstacklibrary.utils.PendingTransactionManager;
-import com.javafullstacklibrary.dao.LoanDAO;
 import com.javafullstacklibrary.utils.UserSession;
 
-import jakarta.persistence.EntityManager;
-import jakarta.persistence.EntityManagerFactory;
-import jakarta.persistence.Persistence;
-
 import java.time.LocalDate;
 import java.util.List;
 
@@ -36,13 +30,9 @@ public class LoanReceiptBorrowerController {
     @FXML
     private Button printLoanRecieptBorrower;
 
-    private LoanDAO loanDAO;
-    private EntityManager entityManager;
+    
 
     public void initialize() {
-        EntityManagerFactory emf = Persistence.createEntityManagerFactory("libraryPU");
-        this.entityManager = emf.createEntityManager();
-        this.loanDAO = new LoanDAO(entityManager);
         displayLoanReceipt();
     }
 
@@ -82,19 +72,10 @@ private void displayLoanReceipt() {
         }
 
         // Process the loans in the database
-        processLoans(loanedItems);
-    }
-
-    private void processLoans(List<ItemCopy> itemCopies) {
-        // do this with the DOA:
-        LibraryUser loaner = UserSession.getCurrentUser();
-        for (ItemCopy itemCopy : itemCopies) {
-            loanDAO.save(itemCopy, loaner, getReturnDateByItemCopy(itemCopy));
-        }
-        // Clear the pending loans list after successful processing
         PendingTransactionManager.getInstance().clearPending();
     }
 
+
     private LocalDate getReturnDateByItemCopy(ItemCopy itemCopy) {
         // First extract the item from the ItemCopy
         Item item = itemCopy.getItem();
diff --git a/src/main/java/com/javafullstacklibrary/frontend/borrowerControllers/LoanViewBorrowerController.java b/src/main/java/com/javafullstacklibrary/frontend/borrowerControllers/LoanViewBorrowerController.java
@@ -15,7 +15,6 @@
 import com.javafullstacklibrary.utils.MenuNavigationHelper;
 import com.javafullstacklibrary.utils.PendingTransactionManager;
 import com.javafullstacklibrary.utils.UserSession;
-
 import java.util.List;
 
 public class LoanViewBorrowerController {
@@ -41,6 +40,7 @@ public class LoanViewBorrowerController {
     @FXML
     private Label statusLabel;
 
+
     public void initialize() {
         loadPendingLoans();
     }
@@ -135,8 +135,12 @@ private void clickedAddLoanButton() {
                 return;
             }
             
-            if (!loanValidationService.canLoanMore(UserSession.getCurrentUser(), PendingTransactionManager.getInstance())) {
-                showErrorMessage("You have reached the maximum number of pending loans allowed for your user type.");
+            // Use service to validate if user can add more items to pending
+            ValidationResult<Void> addValidation = loanValidationService.validateAddToPending(
+                UserSession.getCurrentUser(), PendingTransactionManager.getInstance());
+            
+            if (!addValidation.isSuccess()) {
+                showErrorMessage(addValidation.getMessage());
                 return;
             }
             
@@ -152,14 +156,36 @@ private void clickedAddLoanButton() {
 
     @FXML
     private void clickedConfirmLoansButtonBorrower() {
-        List<ItemCopy> pendingLoans = PendingTransactionManager.getInstance().getPending();
-        
-        if (pendingLoans.isEmpty()) {
-            showErrorMessage("No items selected for loan");
-            return;
+        try (LoanValidationService loanValidationService = new LoanValidationService()) {
+            // Use service to validate loan confirmation
+            ValidationResult<Void> confirmationResult = loanValidationService.validateLoanConfirmation(
+                UserSession.getCurrentUser(), PendingTransactionManager.getInstance());
+            
+            if (!confirmationResult.isSuccess()) {
+                showErrorMessage(confirmationResult.getMessage());
+                return;
+            }
+            
+            List<ItemCopy> pendingLoans = PendingTransactionManager.getInstance().getPending();
+            
+            // Use service to process the loans
+            ValidationResult<Void> processResult = loanValidationService.processLoans(
+                pendingLoans, UserSession.getCurrentUser());
+            
+            if (!processResult.isSuccess()) {
+                showErrorMessage(processResult.getMessage());
+                return;
+            }
+            
+            // Clear pending loans after successful processing
+            PendingTransactionManager.getInstance().clearPending();
+            
+            showSuccessMessage("Loans confirmed successfully");
+            MenuNavigationHelper.buttonClickBorrower(mainPane, "LoanReceipt");
+        } catch (Exception e) {
+            System.err.println("Error processing loans: " + e.getMessage());
+            showErrorMessage("Error processing loan request");
         }
-        
-        MenuNavigationHelper.buttonClickBorrower(mainPane, "LoanReceipt");
     }
 
     /**
@@ -187,7 +213,7 @@ private void addItemToLoanContainer(ItemCopy itemCopy) {
         itemContainer.getChildren().addAll(itemLabel, removeButton);
         loanContainer.getChildren().add(itemContainer);
     }
-    
+
     private void clearStatusMessage() {
         statusLabel.setVisible(false);
         statusLabel.setManaged(false);
diff --git a/src/main/java/com/javafullstacklibrary/services/LoanValidationService.java b/src/main/java/com/javafullstacklibrary/services/LoanValidationService.java
@@ -3,6 +3,7 @@
 import com.javafullstacklibrary.dao.ItemCopyDAO;
 import com.javafullstacklibrary.dao.LoanDAO;
 
+import com.javafullstacklibrary.model.Item;
 import com.javafullstacklibrary.model.ItemCopy;
 import com.javafullstacklibrary.model.Journal;
 import com.javafullstacklibrary.model.LibraryUser;
@@ -12,6 +13,8 @@
 import jakarta.persistence.EntityManagerFactory;
 import jakarta.persistence.Persistence;
 
+import java.time.LocalDate;
+import java.util.List;
 import java.util.Optional;
 
 public class LoanValidationService implements AutoCloseable {
@@ -96,6 +99,90 @@ public ValidationResult<ItemCopy> validateBarcodeForLoan(String barcode) {
         return ValidationResult.success(itemCopy);
     }
 
+    /**
+     * Validates if the user can confirm all pending loans without exceeding their limit
+     * @param libraryUser The user requesting the loans
+     * @param pendingTransactionManager The pending transaction manager containing items to loan
+     * @return ValidationResult indicating success or failure with appropriate message
+     */
+    public ValidationResult<Void> validateLoanConfirmation(LibraryUser libraryUser, PendingTransactionManager pendingTransactionManager) {
+        if (pendingTransactionManager.getPending().isEmpty()) {
+            return ValidationResult.failure("No items selected for loan");
+        }
+        
+        int maxLoans = loanDAO.getMaxLoansByUser(libraryUser);
+        int currentActiveLoans = Math.toIntExact(loanDAO.countActiveLoansByUser(libraryUser));
+        int pendingCount = pendingTransactionManager.getPendingCount();
+        
+        if (maxLoans != -1 && (currentActiveLoans + pendingCount) > maxLoans) {
+            return ValidationResult.failure(String.format(
+                "Cannot confirm loans: would exceed maximum limit of %d loans (current: %d, pending: %d)", 
+                maxLoans, currentActiveLoans, pendingCount));
+        }
+        
+        return ValidationResult.success(null);
+    }
+
+    /**
+     * Validates if a user can add one more item to their pending loans
+     * @param libraryUser The user requesting to add an item
+     * @param pendingTransactionManager The pending transaction manager
+     * @return ValidationResult indicating success or failure
+     */
+    public ValidationResult<Void> validateAddToPending(LibraryUser libraryUser, PendingTransactionManager pendingTransactionManager) {
+        int maxLoans = loanDAO.getMaxLoansByUser(libraryUser);
+        int currentActiveLoans = Math.toIntExact(loanDAO.countActiveLoansByUser(libraryUser));
+        int pendingCount = pendingTransactionManager.getPendingCount();
+        
+        if (maxLoans != -1 && (currentActiveLoans + pendingCount + 1) > maxLoans) {
+            return ValidationResult.failure(String.format(
+                "You have reached the maximum number of loans allowed for your user type (%d)", maxLoans));
+        }
+        
+        return ValidationResult.success(null);
+    }
+    
+    /**
+     * Processes a list of pending loans by creating loan records in the database
+     * @param itemCopies List of ItemCopy objects to loan
+     * @param libraryUser The user taking out the loans
+     * @return ValidationResult indicating success or failure with appropriate message
+     */
+    public ValidationResult<Void> processLoans(List<ItemCopy> itemCopies, LibraryUser libraryUser) {
+        if (itemCopies == null || itemCopies.isEmpty()) {
+            return ValidationResult.failure("No items to process for loan");
+        }
+        
+        if (libraryUser == null) {
+            return ValidationResult.failure("Library user is required for processing loans");
+        }
+        
+        try {
+            // Process each loan
+            for (ItemCopy itemCopy : itemCopies) {
+                LocalDate returnDate = getReturnDateByItemCopy(itemCopy);
+                loanDAO.save(itemCopy, libraryUser, returnDate);
+            }
+            
+            return ValidationResult.success(null);
+        } catch (IllegalStateException e) {
+            return ValidationResult.failure("Loan processing failed: " + e.getMessage());
+        } catch (Exception e) {
+            return ValidationResult.failure("An error occurred while processing loans");
+        }
+    }
+
+    /**
+     * Calculates the return date for an item copy based on its maximum loan time
+     * @param itemCopy The ItemCopy to calculate return date for
+     * @return LocalDate representing when the item should be returned
+     */
+    private LocalDate getReturnDateByItemCopy(ItemCopy itemCopy) {
+        Item item = itemCopy.getItem();
+        int daysToAdd = item.getMaxLoanTimeDays();
+        return LocalDate.now().plusDays(daysToAdd);
+    }
+    
     @Override
     public void close() {
         if (em != null && em.isOpen()) {
