set URL when inferring type

src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java

@@ -13,6 +13,7 @@ import edu.kit.typicalc.model.parser.ParseError;
 import edu.kit.typicalc.presenter.Presenter;
 import edu.kit.typicalc.view.content.infocontent.StartPageView;
 import edu.kit.typicalc.view.content.typeinferencecontent.TypeInferenceView;
+import org.apache.commons.lang3.StringUtils;
 
 import javax.servlet.http.HttpServletResponse;
 import java.nio.charset.StandardCharsets;
@@ -35,14 +36,13 @@ public class MainViewImpl extends AppLayout implements MainView, HasErrorParamet
 
     private final UpperBar upperBar;
 
-    private String termToType = "x"; //todo replace with real value
     /**
      * Creates a new MainViewImpl.
      */
     public MainViewImpl() {
         setDrawerOpened(false);
         MainViewListener presenter = new Presenter(new ModelImpl(), this);
-        upperBar = new UpperBar(presenter, this::setContent);
+        upperBar = new UpperBar(presenter, this::setContent, this::setTermInURL);
         addToNavbar(upperBar);
         addToDrawer(new DrawerContent());
     }
@@ -50,7 +50,6 @@ public class MainViewImpl extends AppLayout implements MainView, HasErrorParamet
     @Override
     public void setTypeInferenceView(final TypeInfererInterface typeInferer) {
         TypeInferenceView tiv = new TypeInferenceView(typeInferer);
-        UI.getCurrent().getPage().getHistory().replaceState(null, new Location(ROUTE + SLASH + termToType));
         setContent(tiv);
     }
 
@@ -70,14 +69,20 @@ public class MainViewImpl extends AppLayout implements MainView, HasErrorParamet
             List<String> segments = event.getLocation().getSegments();
             String term = segments.get(segments.size() - 1);
             upperBar.inferTerm(decodeURL(term));
-            return HttpServletResponse.SC_OK;
+        } else if (event.getLocation().getPath().equals(ROUTE)) {
+            setContent(new StartPageView());
+            upperBar.inferTerm(StringUtils.EMPTY);
         } else if (event.getLocation().getPath().equals("")) {
             setContent(new StartPageView());
-            return HttpServletResponse.SC_OK;
         } else {
-            setContent(new NotFoundView(event));
+            setContent(new NotFoundView());
             return HttpServletResponse.SC_NOT_FOUND;
         }
+        return HttpServletResponse.SC_OK;
+    }
+
+    protected void setTermInURL(String lambdaTerm) {
+        UI.getCurrent().getPage().getHistory().replaceState(null, new Location(ROUTE + SLASH + lambdaTerm));
     }
 
     private String decodeURL(String encodedUrl) {

src/main/java/edu/kit/typicalc/view/main/NotFoundView.java

@@ -1,17 +1,18 @@
 package edu.kit.typicalc.view.main;
 
-import com.vaadin.flow.component.html.Label;
+import com.vaadin.flow.component.html.H1;
+import com.vaadin.flow.component.html.H2;
 import com.vaadin.flow.component.orderedlayout.VerticalLayout;
-import com.vaadin.flow.router.BeforeEnterEvent;
 import com.vaadin.flow.router.ParentLayout;
 
 @ParentLayout(MainViewImpl.class)
 public class NotFoundView extends VerticalLayout {
 
 
-    public NotFoundView(BeforeEnterEvent event) {
+    public NotFoundView() {
-        Label error = new Label(event.getLocation().getPath());
+        H1 error404 = new H1("404 - Not found");
-        add(error);
+        H2 suggestion = new H2("Try \"/infer/<term>\" or type your favourite term into the input field");
+        add(error404, suggestion); // todo make beautiful
         setAlignItems(Alignment.CENTER);
     }
 }

src/main/java/edu/kit/typicalc/view/main/UpperBar.java

@@ -10,6 +10,7 @@ import com.vaadin.flow.component.html.H1;
 import com.vaadin.flow.component.icon.Icon;
 import com.vaadin.flow.component.icon.VaadinIcon;
 import com.vaadin.flow.component.orderedlayout.HorizontalLayout;
+import com.vaadin.flow.router.Location;
 import edu.kit.typicalc.view.content.infocontent.StartPageView;
 import edu.kit.typicalc.view.main.MainView.MainViewListener;
 import org.apache.commons.lang3.StringUtils;
@@ -40,16 +41,21 @@ public class UpperBar extends HorizontalLayout {
 
     private final transient MainViewListener presenter;
     private final transient Consumer<Component> setContent;
+    private final transient Consumer<String> setTermInURL;
 
     /**
      * Initializes a new UpperBar with the provided mainViewListener.
      *
      * @param presenter the listener used to communicate with the model
      * @param setContent function to set the content of the application
+     * @param setTermInURL function to set the term into the URL
      */
-    protected UpperBar(final MainViewListener presenter, final Consumer<Component> setContent) {
+    protected UpperBar(final MainViewListener presenter, final Consumer<Component> setContent,
+                       final Consumer<String> setTermInURL) {
+
         this.presenter = presenter;
         this.setContent = setContent;
+        this.setTermInURL = setTermInURL;
 
         this.viewTitle = new H1(getTranslation("root.typicalc"));
         viewTitle.addClickListener(event -> routeToStartPage());
@@ -74,17 +80,18 @@ public class UpperBar extends HorizontalLayout {
      * @param lambdaString the lambda term to be type-inferred
      */
     protected void typeInfer(final String lambdaString) {
-        inputBar.reset(); //TODO should term remain in input field?
+//        inputBar.reset(); //TODO should term remain in input field?
-        
+        setTermInURL.accept(lambdaString);
         presenter.typeInferLambdaString(lambdaString, new HashMap<>());
-        if (lambdaString.equals(StringUtils.EMPTY)) {
+        // todo ich finde es ohne Wechsel auf Startseite besser, man bekommt ja schon ne Warnung
-            routeToStartPage();
+//        if (lambdaString.equals(StringUtils.EMPTY)) {
-        }
+//            routeToStartPage();
+//        }
     }
 
     private void routeToStartPage() {
         setContent.accept(new StartPageView());
-        UI.getCurrent().getPage().getHistory().replaceState(null, StringUtils.EMPTY);
+        UI.getCurrent().getPage().getHistory().replaceState(null, new Location(StringUtils.EMPTY));
     }
 
     private void onHelpIconClick() {