public virtual void OnGUI()

in Editor/Scripts/MessageEditor.cs [125:177]
46 lines of code
8 McCabe index (conditional complexity)

        public virtual void OnGUI()
        {
            GUILayout.Space(15);
            using (var check = new EditorGUI.ChangeCheckScope())
            {
                m_EditorState.useAdvanced = !GUILayout.Toggle(
                    !m_EditorState.useAdvanced, "  Use default parameters", EditorStyles.radioButton);
                EditorGUILayout.LabelField(basicInfo, EditorStyles.wordWrappedLabel);

                m_EditorState.useAdvanced = GUILayout.Toggle(
                    m_EditorState.useAdvanced, "  Use custom parameters", EditorStyles.radioButton);

                if (m_EditorState.useAdvanced)
                {
                    if (m_FieldList == null) RebuildList();
                    m_FieldList.displayRemove = m_EditorState.fields.Count > 1;

                    m_FieldList.DoLayoutList();

                    GUILayout.Space(15);
                    if (!string.IsNullOrEmpty(m_ErrorMessage))
                    {
                        EditorGUILayout.HelpBox(m_ErrorMessage, MessageType.Error);
                        GUILayout.Space(5);
                    }
                }

                if (check.changed)
                {
                    CheckValidationErrors();
                    CacheState();
                }
            }

            if (hasChanges)
            {
                EditorGUILayout.HelpBox(
                    "You have unsaved changes.\n" +
                    "Note that saving changes will cause project to recompile.", MessageType.Info);
            }

            GUILayout.Space(5);
            using (new EditorGUI.DisabledGroupScope(!hasChanges))
            using (new EditorGUILayout.HorizontalScope())
            {
                GUILayout.FlexibleSpace();
                if (GUILayout.Button("Revert", Styles.button, GUILayout.ExpandWidth(false))) RevertState();
                using (new EditorGUI.DisabledGroupScope(!string.IsNullOrEmpty(m_ErrorMessage)))
                {
                    if (GUILayout.Button("Apply", Styles.button, GUILayout.ExpandWidth(false))) SaveState();
                }
            }
        }