Support IF on public surveys

README.md

@@ -112,13 +112,13 @@ When a value for _success_ is defined, the field with the action tag will be set
 
 ### Combining **@SURVEY-AUTH** with **@IF**
 
-The **@SURVEY-AUTH** action tag can be used inside **@IF** (since v1.4.0), but only on non-public surveys.
-For public surveys, as long as **@SURVEY-AUTH** is present _anywhere_ (even when inside the _false part_ of an @IF), the survey taker will need to log in before being able to proceed.
+The **@SURVEY-AUTH** action tag can be used inside **@IF** action tags. Note that in public surveys, the record does not exist yet, and does any logic should be restricted to record-independent elements, such as e.g. the [arm-number], [arm-label] or the aggregate smart variables.
 
 ## [Changelog](#changelog)
 
 Release | Description
 ------- | ---------------------
+v1.4.1  | Bugfix: @SURVEY-AUTH with @IF works now in public surveys.
 v1.4.0  | Compatiblity fix: @SURVEY-AUTH can now be used inside @IF; Bugfix: Some JavaScript was missing from the login page; Minimum REDCap version is 12.0.7.
 v1.3.1  | Changed the way the url for login form submission is generated.
 v1.3.0  | New feature: Login for non-public surveys. Simply add the @SURVEY-AUTH action tag (this must first be enabled in the system settings of the module). Enhancement: The token is not required any longer, but instead replaced by a setting that controls whether the module may write data to a record (during an upgrade, tokens are deleted and write mode set to ON).

SurveyAuthExternalModule.php

@@ -41,10 +41,14 @@ function redcap_survey_page_top($project_id, $record, $instrument, $event_id, $g
             $record = \Survey::getRecordFromPartId([$participant_id])[$participant_id];
             if ($record != null) {
                 // We can be sure that the record exists! So we can safely do this:
-                // We must set this to something other than 0 in order to get @IF action tag parsing to work. Duh.
+                // We must set this to something other than 0 in order to get @IF action tag parsing to work (Form::evaluateIfActionTag() relies on this global).
                 $GLOBALS["hidden_edit"] = 1;
             }
         }
+        if (\Survey::isPublicSurvey() && $record == null) {
+            // This is a hack to work around a bug in Form::evaluateIfActionTag() /REDCap::evaluateLogic() 
+            $record = "__some_record_id_that_should_definitely_NOT_exist___" . \Crypto::getGuid();
+        }
 
         $this->settings = new SurveyAuthSettings($this);
 
@@ -208,7 +212,7 @@ private function getTaggedFields($dataDictionary, $project_id, $record, $event_i
     {
         $fields = array();
         foreach ($dataDictionary as $fieldInfo) {
-            $evaluatedFieldAnnotation = \Survey::isPublicSurvey() ? $fieldInfo->field_annotation : \Form::replaceIfActionTag($fieldInfo->field_annotation, $project_id, $record, $event_id, $instrument, $repeat_instance);
+            $evaluatedFieldAnnotation = \Form::replaceIfActionTag($fieldInfo->field_annotation, $project_id, $record, $event_id, $instrument, $repeat_instance);
             if (strpos($evaluatedFieldAnnotation, "@".SurveyAuthExternalModule::$ACTIONTAG)) {
                 array_push($fields, new SurveyAuthInfo($fieldInfo, $dataDictionary));
             }
@@ -292,6 +296,10 @@ function authenticate($username, $password, $project_id, $instrument, $event_id,
                 else {
                     // Use first, any further are ignored
                     $tf = $taggedFields[0];
+                    // If this is a public survey, we need to set $record to null
+                    if (\Survey::isPublicSurvey()) {
+                        $record = null;
+                    }
                     // If this is a nonpublic survey, $record will be set so
                     // just update that record. Otherwise, create new record. 
                     $record = $record ?? $this->addAutoNumberedRecord();