better migration to the new permission process

scripts/upgrade

@@ -52,33 +52,26 @@ if [ -z "$final_path" ]; then
 	ynh_app_setting_set --app=$app --key=final_path --value=$final_path
 fi
 
-# If nobody installed your app before 3.7, then you may
-# safely remove these lines
+### If nobody installed your app before 3.7,
+### then you may safely remove these lines
 
 # Cleaning legacy permissions
 is_public=$(ynh_app_setting_get --app=$app --key=is_public)
-skipped_uris=$(ynh_app_setting_get --app=$app --key=skipped_uris)
-unprotected_uris=$(ynh_app_setting_get --app=$app --key=unprotected_uris)
-protected_uris=$(ynh_app_setting_get --app=$app --key=protected_uris)
 
-# Remove is_public if exists
-if [ ! -z "$is_public" ]; then
-	ynh_app_setting_delete --app=$app --key=is_public
-fi
-
-# Remove skipped_uris if exists
-if [ ! -z "$skipped_uris" ]; then
+if [ -n "$is_public" ]; then
+	# Remove skipped_uris
 	ynh_app_setting_delete --app=$app --key=skipped_uris
-fi
-
-# Remove unprotected_uris if exists
-if [ ! -z "$unprotected_uris" ]; then
+	# Remove unprotected_uris
 	ynh_app_setting_delete --app=$app --key=unprotected_uris
-fi
-
-# Remove protected_uris if exists
-if [ ! -z "$protected_uris" ]; then
+	# Remove protected_uris
 	ynh_app_setting_delete --app=$app --key=protected_uris
+
+	# Removing skipped/unprotected_uris under certain conditions, remove the visitors group added during the migration process of 3.7
+	# If the app was public, add visitors again to the main permission
+	if [ $is_public -eq 1 ]; then
+		ynh_permission_update --permission "main" --add "visitors"
+	fi
+	ynh_app_setting_delete --app=$app --key=is_public
 fi
 
 #=================================================