From 2d6b33190c35d48a2842f7062bde11117f19fdf7 Mon Sep 17 00:00:00 2001
From: Moritz Dieing <63721811+moritzdieing@users.noreply.github.com>
Date: Wed, 10 Mar 2021 20:41:40 +0100
Subject: [PATCH] Handle empty type assumptions

---
 .../view/main/TypeAssumptionField.java        | 28 ++++++++++++++-----
 .../view/main/TypeAssumptionsArea.java        |  3 +-
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionField.java b/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionField.java
index 1391656..8033a43 100644
--- a/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionField.java
+++ b/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionField.java
@@ -9,6 +9,7 @@ import com.vaadin.flow.component.icon.VaadinIcon;
 import com.vaadin.flow.component.orderedlayout.HorizontalLayout;
 import com.vaadin.flow.component.textfield.TextField;
 import com.vaadin.flow.data.binder.Binder;
+import com.vaadin.flow.data.value.ValueChangeMode;
 import com.vaadin.flow.i18n.LocaleChangeEvent;
 import com.vaadin.flow.i18n.LocaleChangeObserver;
 import edu.kit.typicalc.model.parser.TypeAssumptionParser;
@@ -48,7 +49,10 @@ public class TypeAssumptionField extends HorizontalLayout implements LocaleChang
     private final transient TypeAssumptionParser parser = new TypeAssumptionParser();
     private final TextField variableInputField;
     private final TextField typeInputField;
-
+    
+    private final Binder<String> varBinder = new Binder<>();
+    private final Binder<String> typeBinder = new Binder<>();
+    
     /**
      * Creates a new TypeAssumptionField with initial values and a callback to remove this
      * type assumption from the {@link TypeAssumptionsArea}.
@@ -81,6 +85,9 @@ public class TypeAssumptionField extends HorizontalLayout implements LocaleChang
         Button deleteButton = new Button(minusIcon, event -> deleteSelf.accept(this));
         deleteButton.setId(ASS_DELETE_BUTTON_ID);
         deleteButton.setTabIndex(-1);
+        variableInputField.addBlurListener(event -> typeBinder.validate());
+        typeInputField.addBlurListener(event -> varBinder.validate());
+
         addValidatior();
         add(variableInputField, typeInputField, deleteButton);
         setId(ASSUMPTIONS_FIELD_ID);
@@ -93,7 +100,7 @@ public class TypeAssumptionField extends HorizontalLayout implements LocaleChang
      * @return true if the variable matches the syntax, false if not
      */
     protected boolean hasCorrectVariable(String variable) {
-        return variable.isEmpty() || TypeAssumptionParser.TYPE_NAME_PATTERN.matcher(variable).matches();
+        return TypeAssumptionParser.TYPE_NAME_PATTERN.matcher(variable).matches();
     }
     
     /**
@@ -103,18 +110,16 @@ public class TypeAssumptionField extends HorizontalLayout implements LocaleChang
      * @return true if the type matches the syntax, false if not
      */
     protected boolean hasCorrectType(String type) {
-        return type.isEmpty() || parser.parseType(parseBackType(type)).isOk();
+        return parser.parseType(parseBackType(type)).isOk();
     }
     
     private void addValidatior() {
-        Binder<String> varBinder = new Binder<>();
         varBinder.forField(variableInputField)
-                .withValidator(this::hasCorrectVariable, StringUtils.EMPTY)
+                .withValidator(var -> (hasCorrectVariable(var) || isEmpty()), StringUtils.EMPTY)
                 .bind(o -> variableInputField.getEmptyValue(), null);
         variableInputField.setReadOnly(false);
-        Binder<String> typeBinder = new Binder<>();
         typeBinder.forField(typeInputField)
-            .withValidator(this::hasCorrectType, StringUtils.EMPTY)
+            .withValidator(type -> (hasCorrectVariable(type) || isEmpty()), StringUtils.EMPTY)
             .bind(o -> typeInputField.getEmptyValue(), null);
         typeInputField.setReadOnly(false);
     }
@@ -129,6 +134,15 @@ public class TypeAssumptionField extends HorizontalLayout implements LocaleChang
         }
         return new String(rawTypeArray);
     }
+    
+    /**
+     * Checks if both text fields of this type assumption are empty.
+     * 
+     * @return true if both text fields are empty, false if not
+     */
+    protected boolean isEmpty() {
+        return getVariable().isEmpty() && getType().isEmpty();
+    }
 
     /**
      * This method is called when the dialog containing this field is reopened. Since Vaadin somehow detaches the
diff --git a/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionsArea.java b/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionsArea.java
index 6eaef76..1910136 100644
--- a/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionsArea.java
+++ b/src/main/java/edu/kit/typicalc/view/main/TypeAssumptionsArea.java
@@ -96,7 +96,8 @@ public class TypeAssumptionsArea extends Dialog implements LocaleChangeObserver
 
     private void closeAction() {
         for (TypeAssumptionField field : fields) {
-            if (!(field.hasCorrectType(field.getType()) && field.hasCorrectVariable(field.getVariable()))) {
+            if (!(field.hasCorrectType(field.getType()) && field.hasCorrectVariable(field.getVariable()))
+                    && !field.isEmpty()) {
                 invalidInputNotification.open();
                 return;
             }