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

@@ -3,15 +3,22 @@ package com.primefactorsolutions.views;
 import com.primefactorsolutions.model.Employee;
 import com.primefactorsolutions.service.EmployeeService;
 import com.vaadin.flow.component.button.Button;
+import com.vaadin.flow.component.html.Anchor;
 import com.vaadin.flow.router.PageTitle;
 import com.vaadin.flow.router.Route;
+import com.vaadin.flow.server.StreamResource;
 import com.vaadin.flow.spring.annotation.SpringComponent;
+import org.apache.poi.ss.usermodel.*;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
 import org.vaadin.firitin.components.grid.PagingGrid;
 import com.vaadin.flow.component.grid.GridSortOrder;
 import com.vaadin.flow.data.provider.SortDirection;
 import jakarta.annotation.security.PermitAll;
 import org.springframework.context.annotation.Scope;
 
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.util.List;
 
 @SpringComponent
@@ -33,9 +40,49 @@ public class EmployeesListView extends BaseView {
     private void setupView() {
         configureTable();
         getCurrentPageLayout().add(createAddEmployeeButton());
+        getCurrentPageLayout().add(createExportButton());
         getCurrentPageLayout().add(table);
     }
 
+    private Button createExportButton() {
+        StreamResource excelResource = new StreamResource("employees.xlsx", this::generateExcel);
+        Anchor downloadLink = new Anchor(excelResource, "Export Employees");
+        downloadLink.getElement().setAttribute("download", true); // Forzar descarga
+        return new Button("Export to Excel", e -> getCurrentPageLayout().add(downloadLink));
+    }
+
+    private ByteArrayInputStream generateExcel() {
+        List<Employee> employees = employeeService.findAllEmployees();
+        try (Workbook workbook = new XSSFWorkbook(); ByteArrayOutputStream out = new ByteArrayOutputStream()) {
+            Sheet sheet = workbook.createSheet("Employees");
+            Row headerRow = sheet.createRow(0);
+            String[] headers = {"ID", "First Name", "Last Name", "Status", "Team"};
+            for (int i = 0; i < headers.length; i++) {
+                Cell cell = headerRow.createCell(i);
+                cell.setCellValue(headers[i]);
+                CellStyle style = workbook.createCellStyle();
+                Font font = workbook.createFont();
+                font.setBold(true);
+                style.setFont(font);
+                cell.setCellStyle(style);
+            }
+            int rowIndex = 1;
+            for (Employee employee : employees) {
+                Row row = sheet.createRow(rowIndex++);
+                row.createCell(0).setCellValue(employee.getId().toString());
+                row.createCell(1).setCellValue(employee.getFirstName());
+                row.createCell(2).setCellValue(employee.getLastName());
+                row.createCell(3).setCellValue(employee.getStatus().toString());
+                row.createCell(4).setCellValue(employee.getTeam().toString());
+            }
+            workbook.write(out);
+            return new ByteArrayInputStream(out.toByteArray());
+        } catch (IOException e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
     private void configureTable() {
         table.setColumns("firstName", "lastName", "status");
         addEditButtonColumn("View", this::navigateToEmployeeView);