From d4a6acbc075a3c7f267f4876f3534e1b37d7a7f9 Mon Sep 17 00:00:00 2001
From: ucrhh <ucrhh@student.kit.edu>
Date: Fri, 5 Mar 2021 12:36:47 +0100
Subject: [PATCH] navigate to startpage when empty term is entered

---
 src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java | 5 +++++
 src/main/java/edu/kit/typicalc/view/main/UpperBar.java     | 4 +++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java b/src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java
index c86500f..920dd5f 100644
--- a/src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java
+++ b/src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java
@@ -94,6 +94,11 @@ public class MainViewImpl extends AppLayout
 
     private void setTermInURL(Pair<String, Map<String, String>> lambdaTermAndAssumptions) {
         String lambdaTerm = lambdaTermAndAssumptions.getLeft();
+        if ("".equals(lambdaTerm)) {
+            UI.getCurrent().getPage().getHistory().pushState(null, new Location(""));
+            setContent(new StartPageView());
+            return;
+        }
         StringBuilder types = new StringBuilder();
         for (Map.Entry<String, String> type : lambdaTermAndAssumptions.getRight().entrySet()) {
             if (types.length() > 0) {
diff --git a/src/main/java/edu/kit/typicalc/view/main/UpperBar.java b/src/main/java/edu/kit/typicalc/view/main/UpperBar.java
index 71a1bf6..1c32ce2 100644
--- a/src/main/java/edu/kit/typicalc/view/main/UpperBar.java
+++ b/src/main/java/edu/kit/typicalc/view/main/UpperBar.java
@@ -69,7 +69,9 @@ public class UpperBar extends HorizontalLayout {
      */
     protected void typeInfer(Pair<String, Map<String, String>> termAndAssumptions) {
         setTermInURL.accept(termAndAssumptions);
-        startInfer(termAndAssumptions.getLeft(), termAndAssumptions.getRight());
+        if (!"".equals(termAndAssumptions.getLeft())) {
+            startInfer(termAndAssumptions.getLeft(), termAndAssumptions.getRight());
+        }
     }
 
     private void startInfer(String term, Map<String, String> typeAssumptions) {