<?php

namespace oat\taoQtiTest\models\cat;

use qtism\data\AssessmentTest;
use qtism\data\AssessmentSection;

/**
 * Computerized Assessment Test Utilities.
 *
 * This class provide utility methods for CAT support in TAO.
 */
class CatUtils
{
    /**
     * Extract CAT Information from Test Definition.
     *
     * This method extracts CAT Information from a given $test defintion. Please find below an example
     * of return value with an adaptive section with QTI Assessment Section Identifier 'S01'.
     *
     * [
     *      'S01' =>
     *      [
     *          'adaptiveEngineRef' => 'http://somewhere.com/api',
     *          'adaptiveSettingsRef' => 'file.xml'
     *      ]
     * ]
     *
     * @param \qtism\data\AssessmentTest $test
     * @param string $namespace (optional) The namespace where to search the "adaptivity" information in the $test definition. If not given, a default namespace will be traversed.
     * @return array
     */
    public static function getCatInfo(AssessmentTest $test, $namespace = '')
    {
        if ($namespace === '') {
            $namespace = CatService::QTI_2X_ADAPTIVE_XML_NAMESPACE;
        }
        
        $info = [];
        
        foreach ($test->getComponentsByClassName('assessmentSection') as $assessmentSection) {
            if (($selection = $assessmentSection->getSelection()) !== null && (($xmlExtension = $selection->getXml())) !== null) {
                $xpath = new \DOMXPath($xmlExtension);
                $xpath->registerNamespace('ais', $namespace);
                
                // Reference QTI assessmentSection identifier.
                $sectionIdentifier = $assessmentSection->getIdentifier();
                $sectionInfo = [];
                
                
                // Get the adaptiveEngineRef.
                foreach ($xpath->query('.//ais:adaptiveItemSelection/ais:adaptiveEngineRef', $xmlExtension) as $adaptiveEngineRef) {
                    $sectionInfo['adaptiveEngineRef'] = $adaptiveEngineRef->getAttribute('href');
                }
                
                // Get the adaptiveSettingsRef.
                foreach ($xpath->query('.//ais:adaptiveItemSelection/ais:adaptiveSettingsRef', $xmlExtension) as $adaptiveSettingsRef) {
                    $sectionInfo['adaptiveSettingsRef'] = $adaptiveSettingsRef->getAttribute('href');
                }

                // Get the qtiUsagedataRef.
                foreach ($xpath->query('.//ais:adaptiveItemSelection/ais:qtiUsagedataRef', $xmlExtension) as $qtiUsagedataRef) {
                    $sectionInfo['qtiUsagedataRef'] = $qtiUsagedataRef->getAttribute('href');
                }

                // Get the qtiUsagedataRef.
                foreach ($xpath->query('.//ais:adaptiveItemSelection/ais:qtiMetadataRef', $xmlExtension) as $qtiMetadataRef) {
                    $sectionInfo['qtiMetadataRef'] = $qtiMetadataRef->getAttribute('href');
                }

                if (!empty($sectionInfo)) {
                    $info[$sectionIdentifier] = $sectionInfo;
                }
            }
        }
        
        return $info;
    }
    
    /**
     * Is a Given Section Adaptive
     *
     * This method checks whether or not a given AssessmentSection object $section is adaptive.
     *
     * @param \qtism\data\AssessmentSection $section
     * @param string $namespace (optional) The namespace where to search the "adaptivity" information in the $test definition. If not given, a default namespace will be traversed.
     *
     * @return boolean
     */
    public static function isAssessmentSectionAdaptive(AssessmentSection $section, $namespace = '')
    {
        if ($namespace === '') {
            $namespace = CatService::QTI_2X_ADAPTIVE_XML_NAMESPACE;
        }
        
        $isAdaptive = false;
        
        if (($selection = $section->getSelection()) !== null && (($xmlExtension = $selection->getXml())) !== null) {
            $xpath = new \DOMXPath($xmlExtension);
            $xpath->registerNamespace('ais', $namespace);
            
            if ($xpath->query('.//ais:adaptiveItemSelection', $xmlExtension)->length > 0) {
                $isAdaptive = true;
            }
        }
        
        return $isAdaptive;
    }
}