Handle logged in users by not requiring username/email

Still post them as hidden to overcome validation, but still overwrite
the values in backend to avoid manipulation

comments.php

@@ -174,6 +174,12 @@ class CommentsPlugin extends Plugin
                 $email = filter_var(urldecode($post['email']), FILTER_SANITIZE_STRING);
                 $title = filter_var(urldecode($post['title']), FILTER_SANITIZE_STRING);
 
+                $user = $this->grav['user'];
+                if ($user->authenticated) {
+                    $name = $user->fullname;
+                    $email = $user->email;
+                }
+
                 /** @var Language $language */
                 $language = $this->grav['language'];
                 $lang = $language->getLanguage();

templates/partials/comments.html.twig

@@ -11,9 +11,21 @@
             {% if field.evaluateDefault %}
                 {% set value = evaluate(field.evaluateDefault) %}
             {% endif %}
-            <div>
+            {% if grav.user.authenticated %}
-                {% include "forms/fields/#{field.type}/#{field.type}.html.twig" %}
+                {% if field.name == 'name' %}
-            </div>
+                    <input type="hidden" name="{{field.name}}" value="{{grav.user.fullname}}">
+                {% elseif field.name == 'email' %}
+                    <input type="hidden" name="{{field.name}}" value="{{grav.user.email}}">
+                {% else %}
+                    <div>
+                        {% include "forms/fields/#{field.type}/#{field.type}.html.twig" %}
+                    </div>                
+                {% endif %}
+            {% else %}
+                <div>
+                    {% include "forms/fields/#{field.type}/#{field.type}.html.twig" %}
+                </div>
+            {% endif %}
         {% endfor %}
 
         <div class="buttons">