added IngredientControllerTest

client/src/main/java/client/Ingredient/IngredientController.java

@@ -23,7 +23,7 @@ public class IngredientController {
     private final RestTemplate restTemplate = new RestTemplate();  // Simplified REST client
 
     @FXML
-    private void handleDeleteIngredient(ActionEvent event) {
+    void handleDeleteIngredient(ActionEvent event) {
         // Get selected ingredient
         Ingredient selectedIngredient = ingredientListView.getSelectionModel().getSelectedItem();
         if (selectedIngredient == null) {

client/src/test/java/client/Ingredient/IngredientControllerTest.java

@@ -0,0 +1,174 @@
+package client.Ingredient;
+
+import com.github.tomakehurst.wiremock.junit5.WireMockTest;
+import commons.Ingredient;
+import javafx.application.Platform;
+import javafx.collections.FXCollections;
+import javafx.event.ActionEvent;
+import javafx.scene.control.Button;
+import javafx.scene.control.ListView;
+import javafx.stage.Stage;
+import javafx.stage.Window;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.lang.reflect.Field;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import static com.github.tomakehurst.wiremock.client.WireMock.delete;
+import static com.github.tomakehurst.wiremock.client.WireMock.deleteRequestedFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.get;
+import static com.github.tomakehurst.wiremock.client.WireMock.getRequestedFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.ok;
+import static com.github.tomakehurst.wiremock.client.WireMock.okJson;
+import static com.github.tomakehurst.wiremock.client.WireMock.stubFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
+import static com.github.tomakehurst.wiremock.client.WireMock.verify;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@WireMockTest(httpPort = 8080)
+class IngredientControllerMockTest {
+
+    private IngredientController controller;
+    private ListView<Ingredient> ingredientListView;
+
+    // starting javaFX and allow use of listview and alert usage
+    @BeforeAll
+    static void initJavaFx() throws Exception {
+        CountDownLatch latch = new CountDownLatch(1);
+        try {
+            Platform.startup(latch::countDown);
+        } catch (IllegalStateException alreadyStarted) {
+            latch.countDown();
+        }
+        assertTrue(latch.await(3, TimeUnit.SECONDS), "JavaFX Platform failed to start");
+        Platform.setImplicitExit(false);
+    }
+//inject fxml fields and create controller + mock UI
+    @BeforeEach
+    void setup() throws Exception {
+        controller = new IngredientController();
+
+        ingredientListView = new ListView<>();
+        ingredientListView.setItems(FXCollections.observableArrayList(
+                new Ingredient("Bread", 1, 2, 3),
+                new Ingredient("Cheese", 2, 2, 2),
+                new Ingredient("Ham", 3, 3, 3)
+        ));
+
+        setPrivateField(controller, "ingredientListView", ingredientListView);
+        setPrivateField(controller, "deleteButton", new Button("Delete"));
+    }
+
+    // pick ingredient -> backend says not in use -> fake delete ingredient
+    @Test
+    void deleteingredientwhennotusedcallsusagethendeleteandclearslist() throws Exception {
+        Ingredient selected = ingredientListView.getItems().get(0);
+        ingredientListView.getSelectionModel().select(selected);
+
+        stubFor(get(urlEqualTo("/api/ingredients/" + selected.getId() + "/usage"))
+                .willReturn(okJson("{\"ingredientId\":" + selected.getId() + ",\"usedInRecipes\":0}")));
+
+        stubFor(delete(urlEqualTo("/api/ingredients/" + selected.getId()))
+                .willReturn(ok()));
+
+        // safe close for show and wait, run controller on JavaFX
+        try (DialogCloser closer = startDialogCloser()) {
+            runOnFxThreadAndWait(() -> controller.handleDeleteIngredient(new ActionEvent()));
+        }
+
+        verify(getRequestedFor(urlEqualTo("/api/ingredients/" + selected.getId() + "/usage")));
+        verify(deleteRequestedFor(urlEqualTo("/api/ingredients/" + selected.getId())));
+
+        assertEquals(0, ingredientListView.getItems().size());
+    }
+
+    //select ingredient -> if used backend says it and show warning -> safety delete but shouldn't happen
+    @Test
+    void deleteIngredientwhenUsedshowsWarningandDoesNotDeleteifDialogClosed() throws Exception {
+        Ingredient selected = ingredientListView.getItems().get(1);
+        ingredientListView.getSelectionModel().select(selected);
+
+        stubFor(get(urlEqualTo("/api/ingredients/" + selected.getId() + "/usage"))
+                .willReturn(okJson("{\"ingredientId\":" + selected.getId() + ",\"usedInRecipes\":2}")));
+
+        stubFor(delete(urlEqualTo("/api/ingredients/" + selected.getId()))
+                .willReturn(ok()));
+
+        //safe close as if user selected cancel
+        try (DialogCloser closer = startDialogCloser()) {
+            runOnFxThreadAndWait(() -> controller.handleDeleteIngredient(new ActionEvent()));
+        }
+
+        // check usage but not delete
+        verify(getRequestedFor(urlEqualTo("/api/ingredients/" + selected.getId() + "/usage")));
+        verify(0, deleteRequestedFor(urlEqualTo("/api/ingredients/" + selected.getId())));
+
+        assertEquals(3, ingredientListView.getItems().size());
+    }
+
+    // fxml helper
+    private static void setPrivateField(Object target, String fieldName, Object value) throws Exception {
+        Field f = target.getClass().getDeclaredField(fieldName);
+        f.setAccessible(true);
+        f.set(target, value);
+    }
+
+    //controller on JavaFX
+    private static void runOnFxThreadAndWait(Runnable action) throws Exception {
+        CountDownLatch latch = new CountDownLatch(1);
+        Platform.runLater(() -> {
+            try {
+                action.run();
+            } finally {
+                latch.countDown();
+            }
+        });
+        assertTrue(latch.await(8, TimeUnit.SECONDS), "FX action timed out");
+    }
+
+    // safe close so that show and wait doesn't wait forever
+    private static DialogCloser startDialogCloser() {
+        AtomicBoolean running = new AtomicBoolean(true);
+
+        Thread t = new Thread(() -> {
+            while (running.get()) {
+                try {
+                    Thread.sleep(50);
+                } catch (InterruptedException ignored) {
+                }
+
+                Platform.runLater(() -> {
+                    for (Window w : Window.getWindows()) {
+                        if (w instanceof Stage stage && stage.isShowing()) {
+                            stage.close();
+                        }
+                    }
+                });
+            }
+        }, "javafx-dialog-closer");
+
+        t.setDaemon(true);
+        t.start();
+
+        return new DialogCloser(running);
+    }
+
+    // dialog closer
+    private static final class DialogCloser implements AutoCloseable {
+        private final AtomicBoolean running;
+
+        private DialogCloser(AtomicBoolean running) {
+            this.running = running;
+        }
+
+        @Override
+        public void close() {
+            running.set(false);
+        }
+    }
+}