src/main/java/com/primefactorsolutions/views/DocumentView.java

@@ -8,13 +8,14 @@ import com.primefactorsolutions.service.EmployeeService;
 import com.vaadin.flow.component.Component;
 import com.vaadin.flow.component.button.Button;
 import com.vaadin.flow.component.combobox.ComboBox;
-import com.vaadin.flow.component.html.H2;
 import com.vaadin.flow.component.notification.Notification;
 import com.vaadin.flow.component.orderedlayout.HorizontalLayout;
 import com.vaadin.flow.component.textfield.TextField;
 import com.vaadin.flow.component.upload.Upload;
 import com.vaadin.flow.component.upload.receivers.MemoryBuffer;
 import com.vaadin.flow.router.*;
+import com.vaadin.flow.server.StreamRegistration;
+import com.vaadin.flow.server.StreamResource;
 import com.vaadin.flow.spring.annotation.SpringComponent;
 import elemental.json.Json;
 import elemental.json.JsonArray;
@@ -25,10 +26,12 @@ import org.springframework.security.core.userdetails.UserDetails;
 import org.vaadin.firitin.form.BeanValidationForm;
 import com.vaadin.flow.spring.security.AuthenticationContext;
 
+import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.util.Base64;
 import java.util.List;
 import java.util.UUID;
+import java.io.InputStream;
 
 @SpringComponent
 @PermitAll
@@ -36,8 +39,6 @@ import java.util.UUID;
 @PageTitle("Document")
 @Route(value = "/documents/:documentId?/:action?", layout = MainLayout.class)
 public class DocumentView extends BeanValidationForm<Document> implements HasUrlParameter<String> {
-
-    private final H2 title = new H2("Edit Documents");
     private final TextField fileName = new TextField("Document Name");
     private final ComboBox<DocumentType> documentType = new ComboBox<>("Document Type");
     private final ComboBox<Employee> employeeComboBox = new ComboBox<>("Employee");
@@ -46,11 +47,11 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
     private final DocumentService documentService;
     private final EmployeeService employeeService;
     private final AuthenticationContext authContext;
-
     private boolean fileUploaded = false;
     private Button saveButton;
     private Button viewDocumentButton;
 
+
     public DocumentView(final DocumentService documentService,
                         final EmployeeService employeeService,
                         final AuthenticationContext authContext) {
@@ -66,34 +67,6 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         configureUploadButton();
     }
 
-    private void configureComponents() {
-        setFileNameProperties();
-        setDocumentTypeProperties();
-        setEmployeeComboBoxProperties();
-    }
-
-    private void setFileNameProperties() {
-        fileName.setWidthFull();
-    }
-
-    private void setDocumentTypeProperties() {
-        documentType.setItems(DocumentType.values());
-        documentType.setWidthFull();
-    }
-
-    private void setEmployeeComboBoxProperties() {
-        List<Employee> employees = employeeService.findAllEmployees();
-        employeeComboBox.setItems(employees);
-        employeeComboBox.setItemLabelGenerator(employee -> employee.getFirstName() + " " + employee.getLastName());
-        employeeComboBox.setWidthFull();
-    }
-
-    private void configureUploadButton() {
-        uploadButton.setMaxFiles(1);
-        uploadButton.setAcceptedFileTypes(".pdf");
-        uploadButton.addSucceededListener(event -> handleUploadSuccess());
-    }
-
     protected Button createSaveButton() {
         saveButton = new Button("Save");
         saveButton.addClickListener(event -> saveDocument());
@@ -113,43 +86,58 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         return viewDocumentButton;
     }
 
+    private void setFileNameProperties() {
+        fileName.setWidthFull();
+    }
+
+    private void setDocumentTypeProperties() {
+        documentType.setItems(DocumentType.values());
+        documentType.setWidthFull();
+    }
+
+    private void setEmployeeComboBoxProperties() {
+        List<Employee> employees = employeeService.findAllEmployees();
+        employeeComboBox.setItems(employees);
+        employeeComboBox.setItemLabelGenerator(employee -> employee.getFirstName() + " " + employee.getLastName());
+        employeeComboBox.setWidthFull();
+    }
+
+    private void setDocumentCreator(final Document document) {
+        authContext.getAuthenticatedUser(UserDetails.class).ifPresent(user -> {
+            document.setCreator(user.getUsername());
+        });
+    }
+
+    private void setFieldsReadOnly(final boolean option) {
+        fileName.setReadOnly(option);
+        documentType.setReadOnly(option);
+        employeeComboBox.setReadOnly(option);
+    }
+
     private void viewDocument() {
-        Document document = getEntity();
+        StreamResource resource;
-        if (document.getFileData() != null && document.getFileData().length > 0) {
+        try {
-            String base64Data = Base64.getEncoder().encodeToString(document.getFileData());
+            InputStream inputStream = buffer.getInputStream();
-            String jsCode = createJsCodeForDocument(base64Data);
+            if (inputStream != null && inputStream.available() > 0) {
-            getElement().executeJs(jsCode);
+                resource = new StreamResource(fileName.getValue(), () -> new ByteArrayInputStream(readFileData()));
-        } else {
+            } else {
-            Notification.show("No file data available to view.");
+                byte[] fileData = getEntity().getFileData();
+                resource = new StreamResource(fileName.getValue(), () -> new ByteArrayInputStream(fileData));
+            }
+            resource.setContentType("application/pdf");
+            getUI().ifPresent(ui -> {
+                StreamRegistration registration = ui.getSession().getResourceRegistry().registerResource(resource);
+                ui.getPage().open(registration.getResourceUri().toString());
+            });
+        } catch (IOException e) {
+            Notification.show("Error reading file.");
         }
     }
 
-    private String createJsCodeForDocument(final String base64Data) {
-        return "var byteCharacters = atob('" + base64Data + "');"
-                + "var byteNumbers = new Array(byteCharacters.length);"
-                + "for (var i = 0; i < byteCharacters.length; i++) {"
-                + "    byteNumbers[i] = byteCharacters.charCodeAt(i);"
-                + "}"
-                + "var byteArray = new Uint8Array(byteNumbers);"
-                + "var blob = new Blob([byteArray], { type: 'application/pdf' });"
-                + "var url = URL.createObjectURL(blob);"
-                + "window.open(url, '_blank');";
-    }
-
-    private void closeForm() {
-        navigateToDocumentsListView();
-    }
-
     private void navigateToDocumentsListView() {
         getUI().ifPresent(ui -> ui.navigate(DocumentsListView.class));
     }
 
-    private void handleUploadSuccess() {
-        fileUploaded = true;
-        Notification.show("File uploaded successfully.");
-        viewDocumentButton.setEnabled(true);
-    }
-
     private void saveDocument() {
         if (isFormValid()) {
             Document document = getEntity();
@@ -167,10 +155,8 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         }
     }
 
-    private void setDocumentCreator(final Document document) {
+    private void closeForm() {
-        authContext.getAuthenticatedUser(UserDetails.class).ifPresent(user -> {
+        navigateToDocumentsListView();
-            document.setCreator(user.getUsername());
-        });
     }
 
     private boolean isFormValid() {
@@ -180,15 +166,6 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
                 && fileUploaded;
     }
 
-    private byte[] readFileData() {
-        try {
-            return buffer.getInputStream().readAllBytes();
-        } catch (IOException e) {
-            Notification.show("Error reading file data.");
-            return new byte[0];
-        }
-    }
-
     private void clearForm() {
         fileName.clear();
         documentType.clear();
@@ -198,10 +175,13 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         viewDocumentButton.setEnabled(false);
     }
 
-    private void setFieldsReadOnly(final boolean option) {
+    private byte[] readFileData() {
-        fileName.setReadOnly(option);
+        try {
-        documentType.setReadOnly(option);
+            return buffer.getInputStream().readAllBytes();
-        employeeComboBox.setReadOnly(option);
+        } catch (IOException e) {
+            Notification.show("Error reading file data.");
+            return new byte[0];
+        }
     }
 
     private void preLoadFile(final Document document) {
@@ -210,8 +190,55 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         jsonObject.put("name", document.getFileName());
         jsonObject.put("progress", 100);
         jsonObject.put("complete", true);
+        jsonObject.put("fileData", Base64.getEncoder().encodeToString(document.getFileData()));
         jsonArray.set(0, jsonObject);
         uploadButton.getElement().setPropertyJson("files", jsonArray);
+        fileUploaded = true;
+    }
+
+    private void updateSaveButtonState() {
+        boolean isModified = !fileName.getValue().equals(getEntity().getFileName())
+                || documentType.getValue() != getEntity().getDocumentType()
+                || employeeComboBox.getValue() != getEntity().getEmployee()
+                || fileUploaded;
+        saveButton.setEnabled(isModified);
+    }
+
+    private void configureComponents() {
+        setFileNameProperties();
+        setDocumentTypeProperties();
+        setEmployeeComboBoxProperties();
+        fileName.addValueChangeListener(e -> updateSaveButtonState());
+        documentType.addValueChangeListener(e -> updateSaveButtonState());
+        employeeComboBox.addValueChangeListener(e -> updateSaveButtonState());
+        uploadButton.addSucceededListener(e -> updateSaveButtonState());
+        uploadButton.getElement().addEventListener("file-remove", event -> updateSaveButtonState());
+    }
+
+    private void configureUploadButton() {
+        uploadButton.setMaxFiles(1);
+        uploadButton.setAcceptedFileTypes(".pdf");
+        uploadButton.addSucceededListener(event -> {
+            fileUploaded = true;
+            updateSaveButtonState();
+        });
+        uploadButton.getElement().addEventListener("file-remove", event -> {
+            fileUploaded = false;
+            updateSaveButtonState();
+        });
+    }
+
+    private void configureViewOrEditAction(final String action, final String documentIdString) {
+        if ("edit".equals(action) && !documentIdString.isEmpty()) {
+            setFieldsReadOnly(false);
+            preLoadFile(getEntity());
+            viewDocumentButton.setEnabled(true);
+        } else if ("view".equals(action) && !documentIdString.isEmpty()) {
+            setFieldsReadOnly(true);
+            preLoadFile(getEntity());
+            saveButton.setEnabled(false);
+            viewDocumentButton.setEnabled(true);
+        }
     }
 
     @Override
@@ -222,6 +249,7 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         if ("new".equals(action)) {
             setEntityWithEnabledSave(new Document());
         } else {
+            assert documentIdString != null;
             UUID documentId = UUID.fromString(documentIdString);
             Document document = documentService.getDocument(documentId);
             setEntity(document);
@@ -231,22 +259,11 @@ public class DocumentView extends BeanValidationForm<Document> implements HasUrl
         }
     }
 
-    private void configureViewOrEditAction(final String action, final String documentIdString) {
-        if ("edit".equals(action) && !documentIdString.isEmpty()) {
-            setFieldsReadOnly(false);
-            preLoadFile(getEntity());
-        } else if ("view".equals(action) && !documentIdString.isEmpty()) {
-            setFieldsReadOnly(true);
-            saveButton.setEnabled(false);
-            viewDocumentButton.setEnabled(true);
-        }
-    }
-
     @Override
     protected List<Component> getFormComponents() {
         HorizontalLayout buttonLayout = new HorizontalLayout();
         buttonLayout.add(uploadButton, createViewDocumentButton());
         buttonLayout.setSpacing(true);
-        return List.of(title, fileName, documentType, employeeComboBox, buttonLayout, createCloseButton());
+        return List.of(fileName, documentType, employeeComboBox, buttonLayout, createCloseButton());
     }
 }