<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * functions used by SCORM 1.2/2004 packages.
 *
 * @package    mod_scorm
 * @copyright 1999 onwards Roberto Pinna
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

function scorm_get_resources($blocks) {
    $resources = array();
    foreach ($blocks as $block) {
        if ($block['name'] == 'RESOURCES' && isset($block['children'])) {
            foreach ($block['children'] as $resource) {
                if ($resource['name'] == 'RESOURCE') {
                    $resources[addslashes_js($resource['attrs']['IDENTIFIER'])] = $resource['attrs'];
                }
            }
        }
    }
    return $resources;
}

function scorm_get_manifest($blocks, $scoes) {
    global $OUTPUT;
    static $parents = array();
    static $resources;

    static $manifest;
    static $organization;

    $manifestresourcesnotfound = array();
    if (count($blocks) > 0) {
        foreach ($blocks as $block) {
            switch ($block['name']) {
                case 'METADATA':
                    if (isset($block['children'])) {
                        foreach ($block['children'] as $metadata) {
                            if ($metadata['name'] == 'SCHEMAVERSION') {
                                if (empty($scoes->version)) {
                                    $isversionset = (preg_match("/^(1\.2)$|^(CAM )?(1\.3)$/", $metadata['tagData'], $matches));
                                    if (isset($metadata['tagData']) && $isversionset) {
                                        $scoes->version = 'SCORM_'.$matches[count($matches) - 1];
                                    } else {
                                        $isversionset = (preg_match("/^2004 (3rd|4th) Edition$/", $metadata['tagData'], $matches));
                                        if (isset($metadata['tagData']) && $isversionset) {
                                            $scoes->version = 'SCORM_1.3';
                                        } else {
                                            $scoes->version = 'SCORM_1.2';
                                        }
                                    }
                                }
                            }
                        }
                    }
                break;
                case 'MANIFEST':
                    $manifest = $block['attrs']['IDENTIFIER'];
                    $organization = '';
                    $resources = array();
                    $resources = scorm_get_resources($block['children']);
                    $scoes = scorm_get_manifest($block['children'], $scoes);
                    if (empty($scoes->elements) || count($scoes->elements) <= 0) {
                        foreach ($resources as $item => $resource) {
                            if (!empty($resource['HREF'])) {
                                $sco = new stdClass();
                                $sco->identifier = $item;
                                $sco->title = $item;
                                $sco->parent = '/';
                                $sco->launch = $resource['HREF'];
                                $sco->scormtype = $resource['ADLCP:SCORMTYPE'];
                                $scoes->elements[$manifest][$organization][$item] = $sco;
                            }
                        }
                    }
                break;
                case 'ORGANIZATIONS':
                    if (!isset($scoes->defaultorg) && isset($block['attrs']['DEFAULT'])) {
                        $scoes->defaultorg = $block['attrs']['DEFAULT'];
                    }
                    if (!empty($block['children'])) {
                        $scoes = scorm_get_manifest($block['children'], $scoes);
                    }
                break;
                case 'ORGANIZATION':
                    $identifier = $block['attrs']['IDENTIFIER'];
                    $organization = '';
                    $scoes->elements[$manifest][$organization][$identifier] = new stdClass();
                    $scoes->elements[$manifest][$organization][$identifier]->identifier = $identifier;
                    $scoes->elements[$manifest][$organization][$identifier]->parent = '/';
                    $scoes->elements[$manifest][$organization][$identifier]->launch = '';
                    $scoes->elements[$manifest][$organization][$identifier]->scormtype = '';

                    $parents = array();
                    $parent = new stdClass();
                    $parent->identifier = $identifier;
                    $parent->organization = $organization;
                    array_push($parents, $parent);
                    $organization = $identifier;

                    if (!empty($block['children'])) {
                        $scoes = scorm_get_manifest($block['children'], $scoes);
                    }

                    array_pop($parents);
                break;
                case 'ITEM':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);

                    $identifier = $block['attrs']['IDENTIFIER'];
                    $scoes->elements[$manifest][$organization][$identifier] = new stdClass();
                    $scoes->elements[$manifest][$organization][$identifier]->identifier = $identifier;
                    $scoes->elements[$manifest][$organization][$identifier]->parent = $parent->identifier;
                    if (!isset($block['attrs']['ISVISIBLE'])) {
                        $block['attrs']['ISVISIBLE'] = 'true';
                    }
                    $scoes->elements[$manifest][$organization][$identifier]->isvisible = $block['attrs']['ISVISIBLE'];
                    if (!isset($block['attrs']['PARAMETERS'])) {
                        $block['attrs']['PARAMETERS'] = '';
                    }
                    $scoes->elements[$manifest][$organization][$identifier]->parameters = $block['attrs']['PARAMETERS'];
                    if (!isset($block['attrs']['IDENTIFIERREF'])) {
                        $scoes->elements[$manifest][$organization][$identifier]->launch = '';
                        $scoes->elements[$manifest][$organization][$identifier]->scormtype = 'asset';
                    } else {
                        $idref = addslashes_js($block['attrs']['IDENTIFIERREF']);
                        $base = '';
                        if (isset($resources[$idref]['XML:BASE'])) {
                            $base = $resources[$idref]['XML:BASE'];
                        }
                        if (!isset($resources[$idref])) {
                            $manifestresourcesnotfound[] = $idref;
                            $scoes->elements[$manifest][$organization][$identifier]->launch = '';
                        } else {
                            $scoes->elements[$manifest][$organization][$identifier]->launch = $base.$resources[$idref]['HREF'];
                            if (empty($resources[$idref]['ADLCP:SCORMTYPE'])) {
                                $resources[$idref]['ADLCP:SCORMTYPE'] = 'asset';
                            }
                            $scoes->elements[$manifest][$organization][$identifier]->scormtype = $resources[$idref]['ADLCP:SCORMTYPE'];
                        }
                    }

                    $parent = new stdClass();
                    $parent->identifier = $identifier;
                    $parent->organization = $organization;
                    array_push($parents, $parent);

                    if (!empty($block['children'])) {
                        $scoes = scorm_get_manifest($block['children'], $scoes);
                    }

                    array_pop($parents);
                break;
                case 'TITLE':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['tagData'])) {
                        $block['tagData'] = '';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->title = $block['tagData'];
                break;
                case 'ADLCP:PREREQUISITES':
                    if ($block['attrs']['TYPE'] == 'aicc_script') {
                        $parent = array_pop($parents);
                        array_push($parents, $parent);
                        if (!isset($block['tagData'])) {
                            $block['tagData'] = '';
                        }
                        $scoes->elements[$manifest][$parent->organization][$parent->identifier]->prerequisites = $block['tagData'];
                    }
                break;
                case 'ADLCP:MAXTIMEALLOWED':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['tagData'])) {
                        $block['tagData'] = '';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->maxtimeallowed = $block['tagData'];
                break;
                case 'ADLCP:TIMELIMITACTION':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['tagData'])) {
                        $block['tagData'] = '';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->timelimitaction = $block['tagData'];
                break;
                case 'ADLCP:DATAFROMLMS':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['tagData'])) {
                        $block['tagData'] = '';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->datafromlms = $block['tagData'];
                break;
                case 'ADLCP:MASTERYSCORE':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['tagData'])) {
                        $block['tagData'] = '';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->masteryscore = $block['tagData'];
                break;
                case 'ADLCP:COMPLETIONTHRESHOLD':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!isset($block['attrs']['MINPROGRESSMEASURE'])) {
                        $block['attrs']['MINPROGRESSMEASURE'] = '1.0';
                    }
                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->threshold = $block['attrs']['MINPROGRESSMEASURE'];
                break;
                case 'ADLNAV:PRESENTATION':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!empty($block['children'])) {
                        foreach ($block['children'] as $adlnav) {
                            if ($adlnav['name'] == 'ADLNAV:NAVIGATIONINTERFACE') {
                                foreach ($adlnav['children'] as $adlnavinterface) {
                                    if ($adlnavinterface['name'] == 'ADLNAV:HIDELMSUI') {
                                        if ($adlnavinterface['tagData'] == 'continue') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hidecontinue = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'previous') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hideprevious = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'exit') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hideexit = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'exitAll') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hideexitall = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'abandon') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hideabandon = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'abandonAll') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hideabandonall = 1;
                                        }
                                        if ($adlnavinterface['tagData'] == 'suspendAll') {
                                            $scoes->elements[$manifest][$parent->organization][$parent->identifier]->hidesuspendall = 1;
                                        }
                                    }
                                }
                            }
                        }
                    }
                break;
                case 'IMSSS:SEQUENCING':
                    $parent = array_pop($parents);
                    array_push($parents, $parent);
                    if (!empty($block['children'])) {
                        foreach ($block['children'] as $sequencing) {
                            if ($sequencing['name'] == 'IMSSS:CONTROLMODE') {
                                if (isset($sequencing['attrs']['CHOICE'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->choice =
                                        $sequencing['attrs']['CHOICE'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['CHOICEEXIT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->choiceexit =
                                        $sequencing['attrs']['CHOICEEXIT'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['FLOW'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->flow =
                                        $sequencing['attrs']['FLOW'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['FORWARDONLY'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->forwardonly =
                                        $sequencing['attrs']['FORWARDONLY'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['USECURRENTATTEMPTOBJECTINFO'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->usecurrentattemptobjectinfo =
                                        $sequencing['attrs']['USECURRENTATTEMPTOBJECTINFO'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['USECURRENTATTEMPTPROGRESSINFO'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->usecurrentattemptprogressinfo =
                                        $sequencing['attrs']['USECURRENTATTEMPTPROGRESSINFO'] == 'true' ? 1 : 0;
                                }
                            }
                            if ($sequencing['name'] == 'IMSSS:DELIVERYCONTROLS') {
                                if (isset($sequencing['attrs']['TRACKED'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->tracked =
                                        $sequencing['attrs']['TRACKED'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['COMPLETIONSETBYCONTENT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->completionsetbycontent =
                                        $sequencing['attrs']['COMPLETIONSETBYCONTENT'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['OBJECTIVESETBYCONTENT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->objectivesetbycontent =
                                        $sequencing['attrs']['OBJECTIVESETBYCONTENT'] == 'true' ? 1 : 0;
                                }
                            }
                            if ($sequencing['name'] == 'ADLSEQ:CONSTRAINEDCHOICECONSIDERATIONS') {
                                if (isset($sequencing['attrs']['CONSTRAINCHOICE'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->constrainChoice =
                                        $sequencing['attrs']['CONSTRAINCHOICE'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['PREVENTACTIVATION'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->preventactivation =
                                        $sequencing['attrs']['PREVENTACTIVATION'] == 'true' ? 1 : 0;
                                }
                            }
                            if ($sequencing['name'] == 'IMSSS:OBJECTIVES') {
                                $objectives = array();
                                foreach ($sequencing['children'] as $objective) {
                                    $objectivedata = new stdClass();
                                    $objectivedata->primaryobj = 0;
                                    switch ($objective['name']) {
                                        case 'IMSSS:PRIMARYOBJECTIVE':
                                            $objectivedata->primaryobj = 1;
                                        case 'IMSSS:OBJECTIVE':
                                            $objectivedata->satisfiedbymeasure = 0;
                                            if (isset($objective['attrs']['SATISFIEDBYMEASURE'])) {
                                                $objectivedata->satisfiedbymeasure =
                                                    $objective['attrs']['SATISFIEDBYMEASURE'] == 'true' ? 1 : 0;
                                            }
                                            $objectivedata->objectiveid = '';
                                            if (isset($objective['attrs']['OBJECTIVEID'])) {
                                                $objectivedata->objectiveid = $objective['attrs']['OBJECTIVEID'];
                                            }
                                            $objectivedata->minnormalizedmeasure = 1.0;
                                            if (!empty($objective['children'])) {
                                                $mapinfos = array();
                                                foreach ($objective['children'] as $objectiveparam) {
                                                    if ($objectiveparam['name'] == 'IMSSS:MINNORMALIZEDMEASURE') {
                                                        if (isset($objectiveparam['tagData'])) {
                                                            $objectivedata->minnormalizedmeasure = $objectiveparam['tagData'];
                                                        } else {
                                                            $objectivedata->minnormalizedmeasure = 0;
                                                        }
                                                    }
                                                    if ($objectiveparam['name'] == 'IMSSS:MAPINFO') {
                                                        $mapinfo = new stdClass();
                                                        $mapinfo->targetobjectiveid = '';
                                                        if (isset($objectiveparam['attrs']['TARGETOBJECTIVEID'])) {
                                                            $mapinfo->targetobjectiveid =
                                                                $objectiveparam['attrs']['TARGETOBJECTIVEID'];
                                                        }
                                                        $mapinfo->readsatisfiedstatus = 1;
                                                        if (isset($objectiveparam['attrs']['READSATISFIEDSTATUS'])) {
                                                            $mapinfo->readsatisfiedstatus =
                                                                $objectiveparam['attrs']['READSATISFIEDSTATUS'] == 'true' ? 1 : 0;
                                                        }
                                                        $mapinfo->writesatisfiedstatus = 0;
                                                        if (isset($objectiveparam['attrs']['WRITESATISFIEDSTATUS'])) {
                                                            $mapinfo->writesatisfiedstatus =
                                                                $objectiveparam['attrs']['WRITESATISFIEDSTATUS'] == 'true' ? 1 : 0;
                                                        }
                                                        $mapinfo->readnormalizemeasure = 1;
                                                        if (isset($objectiveparam['attrs']['READNORMALIZEDMEASURE'])) {
                                                            $mapinfo->readnormalizemeasure =
                                                                $objectiveparam['attrs']['READNORMALIZEDMEASURE'] == 'true' ? 1 : 0;
                                                        }
                                                        $mapinfo->writenormalizemeasure = 0;
                                                        if (isset($objectiveparam['attrs']['WRITENORMALIZEDMEASURE'])) {
                                                            $mapinfo->writenormalizemeasure =
                                                                $objectiveparam['attrs']['WRITENORMALIZEDMEASURE'] == 'true' ? 1 : 0;
                                                        }
                                                        array_push($mapinfos, $mapinfo);
                                                    }
                                                }
                                                if (!empty($mapinfos)) {
                                                    $objectivesdata->mapinfos = $mapinfos;
                                                }
                                            }
                                        break;
                                    }
                                    array_push($objectives, $objectivedata);
                                }
                                $scoes->elements[$manifest][$parent->organization][$parent->identifier]->objectives = $objectives;
                            }
                            if ($sequencing['name'] == 'IMSSS:LIMITCONDITIONS') {
                                if (isset($sequencing['attrs']['ATTEMPTLIMIT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->attemptLimit =
                                        $sequencing['attrs']['ATTEMPTLIMIT'];
                                }
                                if (isset($sequencing['attrs']['ATTEMPTABSOLUTEDURATIONLIMIT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->attemptAbsoluteDurationLimit =
                                        $sequencing['attrs']['ATTEMPTABSOLUTEDURATIONLIMIT'];
                                }
                            }
                            if ($sequencing['name'] == 'IMSSS:ROLLUPRULES') {
                                if (isset($sequencing['attrs']['ROLLUPOBJECTIVESATISFIED'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->rollupobjectivesatisfied =
                                        $sequencing['attrs']['ROLLUPOBJECTIVESATISFIED'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['ROLLUPPROGRESSCOMPLETION'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->rollupprogresscompletion =
                                        $sequencing['attrs']['ROLLUPPROGRESSCOMPLETION'] == 'true' ? 1 : 0;
                                }
                                if (isset($sequencing['attrs']['OBJECTIVEMEASUREWEIGHT'])) {
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->objectivemeasureweight =
                                        $sequencing['attrs']['OBJECTIVEMEASUREWEIGHT'];
                                }

                                if (!empty($sequencing['children'])) {
                                    $rolluprules = array();
                                    foreach ($sequencing['children'] as $sequencingrolluprule) {
                                        if ($sequencingrolluprule['name'] == 'IMSSS:ROLLUPRULE' ) {
                                            $rolluprule = new stdClass();
                                            $rolluprule->childactivityset = 'all';
                                            if (isset($sequencingrolluprule['attrs']['CHILDACTIVITYSET'])) {
                                                $rolluprule->childactivityset = $sequencingrolluprule['attrs']['CHILDACTIVITYSET'];
                                            }
                                            $rolluprule->minimumcount = 0;
                                            if (isset($sequencingrolluprule['attrs']['MINIMUMCOUNT'])) {
                                                $rolluprule->minimumcount = $sequencingrolluprule['attrs']['MINIMUMCOUNT'];
                                            }
                                            $rolluprule->minimumpercent = 0.0000;
                                            if (isset($sequencingrolluprule['attrs']['MINIMUMPERCENT'])) {
                                                $rolluprule->minimumpercent = $sequencingrolluprule['attrs']['MINIMUMPERCENT'];
                                            }
                                            if (!empty($sequencingrolluprule['children'])) {
                                                foreach ($sequencingrolluprule['children'] as $rolluproleconditions) {
                                                    if ($rolluproleconditions['name'] == 'IMSSS:ROLLUPCONDITIONS') {
                                                        $conditions = array();
                                                        $rolluprule->conditioncombination = 'all';
                                                        if (isset($rolluproleconditions['attrs']['CONDITIONCOMBINATION'])) {
                                                            $rolluprule->CONDITIONCOMBINATION = $rolluproleconditions['attrs']['CONDITIONCOMBINATION'];
                                                        }
                                                        foreach ($rolluproleconditions['children'] as $rolluprulecondition) {
                                                            if ($rolluprulecondition['name'] == 'IMSSS:ROLLUPCONDITION') {
                                                                $condition = new stdClass();
                                                                if (isset($rolluprulecondition['attrs']['CONDITION'])) {
                                                                    $condition->cond = $rolluprulecondition['attrs']['CONDITION'];
                                                                }
                                                                $condition->operator = 'noOp';
                                                                if (isset($rolluprulecondition['attrs']['OPERATOR'])) {
                                                                    $condition->operator = $rolluprulecondition['attrs']['OPERATOR'];
                                                                }
                                                                array_push($conditions, $condition);
                                                            }
                                                        }
                                                        $rolluprule->conditions = $conditions;
                                                    }
                                                    if ($rolluproleconditions['name'] == 'IMSSS:ROLLUPACTION') {
                                                        $rolluprule->rollupruleaction = $rolluproleconditions['attrs']['ACTION'];
                                                    }
                                                }
                                            }
                                            array_push($rolluprules, $rolluprule);
                                        }
                                    }
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->rolluprules = $rolluprules;
                                }
                            }

                            if ($sequencing['name'] == 'IMSSS:SEQUENCINGRULES') {
                                if (!empty($sequencing['children'])) {
                                    $sequencingrules = array();
                                    foreach ($sequencing['children'] as $conditionrules) {
                                        $conditiontype = -1;
                                        switch($conditionrules['name']) {
                                            case 'IMSSS:PRECONDITIONRULE':
                                                $conditiontype = 0;
                                            break;
                                            case 'IMSSS:POSTCONDITIONRULE':
                                                $conditiontype = 1;
                                            break;
                                            case 'IMSSS:EXITCONDITIONRULE':
                                                $conditiontype = 2;
                                            break;
                                        }
                                        if (!empty($conditionrules['children'])) {
                                            $sequencingrule = new stdClass();
                                            foreach ($conditionrules['children'] as $conditionrule) {
                                                if ($conditionrule['name'] == 'IMSSS:RULECONDITIONS') {
                                                    $ruleconditions = array();
                                                    $sequencingrule->conditioncombination = 'all';
                                                    if (isset($conditionrule['attrs']['CONDITIONCOMBINATION'])) {
                                                        $sequencingrule->conditioncombination = $conditionrule['attrs']['CONDITIONCOMBINATION'];
                                                    }
                                                    foreach ($conditionrule['children'] as $rulecondition) {
                                                        if ($rulecondition['name'] == 'IMSSS:RULECONDITION') {
                                                            $condition = new stdClass();
                                                            if (isset($rulecondition['attrs']['CONDITION'])) {
                                                                $condition->cond = $rulecondition['attrs']['CONDITION'];
                                                            }
                                                            $condition->operator = 'noOp';
                                                            if (isset($rulecondition['attrs']['OPERATOR'])) {
                                                                $condition->operator = $rulecondition['attrs']['OPERATOR'];
                                                            }
                                                            $condition->measurethreshold = 0.0000;
                                                            if (isset($rulecondition['attrs']['MEASURETHRESHOLD'])) {
                                                                $condition->measurethreshold = $rulecondition['attrs']['MEASURETHRESHOLD'];
                                                            }
                                                            $condition->referencedobjective = '';
                                                            if (isset($rulecondition['attrs']['REFERENCEDOBJECTIVE'])) {
                                                                $condition->referencedobjective = $rulecondition['attrs']['REFERENCEDOBJECTIVE'];
                                                            }
                                                            array_push($ruleconditions, $condition);
                                                        }
                                                    }
                                                    $sequencingrule->ruleconditions = $ruleconditions;
                                                }
                                                if ($conditionrule['name'] == 'IMSSS:RULEACTION') {
                                                    $sequencingrule->action = $conditionrule['attrs']['ACTION'];
                                                }
                                                $sequencingrule->type = $conditiontype;
                                            }
                                            array_push($sequencingrules, $sequencingrule);
                                        }
                                    }
                                    $scoes->elements[$manifest][$parent->organization][$parent->identifier]->sequencingrules = $sequencingrules;
                                }
                            }
                        }
                    }
                break;
            }
        }
    }
    if (!empty($manifestresourcesnotfound)) {
        // Throw warning to user to let them know manifest contains references to resources that don't appear to exist.
        if (!defined('DEBUGGING_PRINTED')) {
            // Prevent redirect and display warning.
            define('DEBUGGING_PRINTED', 1);
        }
        echo $OUTPUT->notification(get_string('invalidmanifestresource', 'scorm').' '. implode(', ', $manifestresourcesnotfound));
    }
    return $scoes;
}

/**
 * Sets up SCORM 1.2/2004 packages using the manifest file.
 * Called whenever SCORM changes
 * @param object $scorm instance - fields are updated and changes saved into database
 * @param stored_file|string $manifest - path to manifest file or stored_file.
 * @return bool
 */
function scorm_parse_scorm(&$scorm, $manifest) {
    global $CFG, $DB;

    // Load manifest into string.
    if ($manifest instanceof stored_file) {
        $xmltext = $manifest->get_content();
    } else {
        require_once("$CFG->libdir/filelib.php");
        $xmltext = download_file_content($manifest);
    }

    $defaultorgid = 0;
    $firstinorg = 0;

    $pattern = '/&(?!\w{2,6};)/';
    $replacement = '&amp;';
    $xmltext = preg_replace($pattern, $replacement, $xmltext);

    $objxml = new xml2Array();
    $manifests = $objxml->parse($xmltext);
    $scoes = new stdClass();
    $scoes->version = '';
    $scoes = scorm_get_manifest($manifests, $scoes);
    $newscoes = array();
    $sortorder = 0;

<     if (count($scoes->elements) > 0) {



>     if (!empty($scoes->elements) && is_iterable($scoes->elements)) {


        $olditems = $DB->get_records('scorm_scoes', array('scorm' => $scorm->id));
        foreach ($scoes->elements as $manifest => $organizations) {
            foreach ($organizations as $organization => $items) {
                foreach ($items as $identifier => $item) {
                    $sortorder++;
                    // This new db mngt will support all SCORM future extensions.
                    $newitem = new stdClass();
                    $newitem->scorm = $scorm->id;
                    $newitem->manifest = $manifest;
                    $newitem->organization = $organization;
                    $newitem->sortorder = $sortorder;
                    $standarddatas = array('parent', 'identifier', 'launch', 'scormtype', 'title');
                    foreach ($standarddatas as $standarddata) {
                        if (isset($item->$standarddata)) {
                            $newitem->$standarddata = $item->$standarddata;
                        } else {
                            $newitem->$standarddata = '';
                        }
                    }

                    if (!empty($defaultorgid) && !empty($scoes->defaultorg) && empty($firstinorg) &&
                        $newitem->parent == $scoes->defaultorg) {

                        $firstinorg = $sortorder;
                    }

                    if (!empty($olditems) && ($olditemid = scorm_array_search('identifier', $newitem->identifier, $olditems))) {
                        $newitem->id = $olditemid;
                        // Update the Sco sortorder but keep id so that user tracks are kept against the same ids.
                        $DB->update_record('scorm_scoes', $newitem);
                        $id = $olditemid;
                        // Remove all old data so we don't duplicate it.
                        $DB->delete_records('scorm_scoes_data', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_objective', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_mapinfo', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_ruleconds', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_rulecond', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_rolluprule', array('scoid' => $olditemid));
                        $DB->delete_records('scorm_seq_rolluprulecond', array('scoid' => $olditemid));

                        // Now remove this SCO from the olditems object as we have dealt with it.
                        unset($olditems[$olditemid]);
                    } else {
                        // Insert the new SCO, and retain the link between the old and new for later adjustment.
                        $id = $DB->insert_record('scorm_scoes', $newitem);
                    }
                    // Save this sco in memory so we can use it later.
                    $newscoes[$id] = $newitem;

                    if ($optionaldatas = scorm_optionals_data($item, $standarddatas)) {
                        $data = new stdClass();
                        $data->scoid = $id;
                        foreach ($optionaldatas as $optionaldata) {
                            if (isset($item->$optionaldata)) {
                                $data->name = $optionaldata;
                                $data->value = $item->$optionaldata;
                                $dataid = $DB->insert_record('scorm_scoes_data', $data);
                            }
                        }
                    }

                    if (isset($item->sequencingrules)) {
                        foreach ($item->sequencingrules as $sequencingrule) {
                            $rule = new stdClass();
                            $rule->scoid = $id;
                            $rule->ruletype = $sequencingrule->type;
                            $rule->conditioncombination = $sequencingrule->conditioncombination;
                            $rule->action = $sequencingrule->action;
                            $ruleid = $DB->insert_record('scorm_seq_ruleconds', $rule);
                            if (isset($sequencingrule->ruleconditions)) {
                                foreach ($sequencingrule->ruleconditions as $rulecondition) {
                                    $rulecond = new stdClass();
                                    $rulecond->scoid = $id;
                                    $rulecond->ruleconditionsid = $ruleid;
                                    $rulecond->referencedobjective = $rulecondition->referencedobjective;
                                    $rulecond->measurethreshold = $rulecondition->measurethreshold;
                                    $rulecond->operator = $rulecondition->operator;
                                    $rulecond->cond = $rulecondition->cond;
                                    $rulecondid = $DB->insert_record('scorm_seq_rulecond', $rulecond);
                                }
                            }
                        }
                    }

                    if (isset($item->rolluprules)) {
                        foreach ($item->rolluprules as $rolluprule) {
                            $rollup = new stdClass();
                            $rollup->scoid = $id;
                            $rollup->childactivityset = $rolluprule->childactivityset;
                            $rollup->minimumcount = $rolluprule->minimumcount;
                            $rollup->minimumpercent = $rolluprule->minimumpercent;
                            $rollup->rollupruleaction = $rolluprule->rollupruleaction;
                            $rollup->conditioncombination = $rolluprule->conditioncombination;

                            $rollupruleid = $DB->insert_record('scorm_seq_rolluprule', $rollup);
                            if (isset($rollup->conditions)) {
                                foreach ($rollup->conditions as $condition) {
                                    $cond = new stdClass();
                                    $cond->scoid = $rollup->scoid;
                                    $cond->rollupruleid = $rollupruleid;
                                    $cond->operator = $condition->operator;
                                    $cond->cond = $condition->cond;
                                    $conditionid = $DB->insert_record('scorm_seq_rolluprulecond', $cond);
                                }
                            }
                        }
                    }

                    if (isset($item->objectives)) {
                        foreach ($item->objectives as $objective) {
                            $obj = new stdClass();
                            $obj->scoid = $id;
                            $obj->primaryobj = $objective->primaryobj;
                            $obj->satisfiedbumeasure = $objective->satisfiedbymeasure;
                            $obj->objectiveid = $objective->objectiveid;
                            $obj->minnormalizedmeasure = trim($objective->minnormalizedmeasure);
                            $objectiveid = $DB->insert_record('scorm_seq_objective', $obj);
                            if (isset($objective->mapinfos)) {
                                foreach ($objective->mapinfos as $objmapinfo) {
                                    $mapinfo = new stdClass();
                                    $mapinfo->scoid = $id;
                                    $mapinfo->objectiveid = $objectiveid;
                                    $mapinfo->targetobjectiveid = $objmapinfo->targetobjectiveid;
                                    $mapinfo->readsatisfiedstatus = $objmapinfo->readsatisfiedstatus;
                                    $mapinfo->writesatisfiedstatus = $objmapinfo->writesatisfiedstatus;
                                    $mapinfo->readnormalizedmeasure = $objmapinfo->readnormalizedmeasure;
                                    $mapinfo->writenormalizedmeasure = $objmapinfo->writenormalizedmeasure;
                                    $mapinfoid = $DB->insert_record('scorm_seq_mapinfo', $mapinfo);
                                }
                            }
                        }
                    }
                    if (empty($defaultorgid) && ((empty($scoes->defaultorg)) || ($scoes->defaultorg == $identifier))) {
                        $defaultorgid = $id;
                    }
                }
            }
        }
        if (!empty($olditems)) {
            foreach ($olditems as $olditem) {
                $DB->delete_records('scorm_scoes', array('id' => $olditem->id));
                $DB->delete_records('scorm_scoes_data', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_scoes_track', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_objective', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_mapinfo', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_ruleconds', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_rulecond', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_rolluprule', array('scoid' => $olditem->id));
                $DB->delete_records('scorm_seq_rolluprulecond', array('scoid' => $olditem->id));
            }
        }
        if (empty($scoes->version)) {
            $scoes->version = 'SCORM_1.2';
        }
        $DB->set_field('scorm', 'version', $scoes->version, array('id' => $scorm->id));
        $scorm->version = $scoes->version;
    }
    $scorm->launch = 0;
    // Check launch sco is valid.
    if (!empty($defaultorgid) && isset($newscoes[$defaultorgid]) && !empty($newscoes[$defaultorgid]->launch)) {
        // Launch param is valid - do nothing.
        $scorm->launch = $defaultorgid;
    } else if (!empty($defaultorgid) && isset($newscoes[$defaultorgid]) && empty($newscoes[$defaultorgid]->launch)) {
        // The launch is probably the default org so we need to find the first launchable item inside this org.
        $sqlselect = 'scorm = ? AND sortorder >= ? AND '.$DB->sql_isnotempty('scorm_scoes', 'launch', false, true);
        // We use get_records here as we need to pass a limit in the query that works cross db.
        $scoes = $DB->get_records_select('scorm_scoes', $sqlselect, array($scorm->id, $firstinorg), 'sortorder', 'id', 0, 1);
        if (!empty($scoes)) {
            $sco = reset($scoes); // We only care about the first record - the above query only returns one.
            $scorm->launch = $sco->id;
        }
    }
    if (empty($scorm->launch)) {
        // No valid Launch is specified - find the first launchable sco instead.
        $sqlselect = 'scorm = ? AND '.$DB->sql_isnotempty('scorm_scoes', 'launch', false, true);
        // We use get_records here as we need to pass a limit in the query that works cross db.
        $scoes = $DB->get_records_select('scorm_scoes', $sqlselect, array($scorm->id), 'sortorder', 'id', 0, 1);
        if (!empty($scoes)) {
            $sco = reset($scoes); // We only care about the first record - the above query only returns one.
            $scorm->launch = $sco->id;
        }
    }

    return true;
}

function scorm_optionals_data($item, $standarddata) {
    $result = array();
    $sequencingdata = array('sequencingrules', 'rolluprules', 'objectives');
    foreach ($item as $element => $value) {
        if (! in_array($element, $standarddata)) {
            if (! in_array($element, $sequencingdata)) {
                $result[] = $element;
            }
        }
    }
    return $result;
}

function scorm_is_leaf($sco) {
    global $DB;

    if ($DB->record_exists('scorm_scoes', array('scorm' => $sco->scorm, 'parent' => $sco->identifier))) {
        return false;
    }
    return true;
}

function scorm_get_parent($sco) {
    global $DB;

    if ($sco->parent != '/') {
        if ($parent = $DB->get_record('scorm_scoes', array('scorm' => $sco->scorm, 'identifier' => $sco->parent))) {
            return scorm_get_sco($parent->id);
        }
    }
    return null;
}

function scorm_get_children($sco) {
    global $DB;

    $children = $DB->get_records('scorm_scoes', array('scorm' => $sco->scorm, 'parent' => $sco->identifier), 'sortorder, id');
    if (!empty($children)) {
        return $children;
    }
    return null;
}

function scorm_get_available_children($sco) {
    global $DB;

    $res = $DB->get_records('scorm_scoes', array('scorm' => $sco->scorm, 'parent' => $sco->identifier), 'sortorder, id');
    if (!$res || $res == null) {
        return false;
    } else {
        foreach ($res as $sco) {
            $result[] = $sco;
        }
        return $result;
    }
}


< function scorm_get_available_descendent($descend = array(), $sco) {



> function scorm_get_available_descendent($descend, $sco) {


    if ($sco == null) {
        return $descend;
    } else {
        $avchildren = scorm_get_available_children($sco);
        foreach ($avchildren as $avchild) {
            array_push($descend, $avchild);
        }
        foreach ($avchildren as $avchild) {
            scorm_get_available_descendent($descend, $avchild);
        }
    }
}

function scorm_get_siblings($sco) {
    global $DB;

    if ($siblings = $DB->get_records('scorm_scoes', array('scorm' => $sco->scorm, 'parent' => $sco->parent), 'sortorder, id')) {
        unset($siblings[$sco->id]);
        if (!empty($siblings)) {
            return $siblings;
        }
    }
    return null;
}
// Get an array that contains all the parent scos for this sco.
function scorm_get_ancestors($sco) {
    $ancestors = array();
    $continue = true;
    while ($continue) {
        $ancestor = scorm_get_parent($sco);
        if (!empty($ancestor) && $ancestor->id !== $sco->id) {
            $sco = $ancestor;
            $ancestors[] = $ancestor;
            if ($sco->parent == '/') {
                $continue = false;
            }
        } else {
            $continue = false;
        }
    }
    return $ancestors;
}

function scorm_get_preorder(&$preorder = array(), $sco = null) {
    if ($sco != null) {
        array_push($preorder, $sco);
        if ($children = scorm_get_children($sco)) {
            foreach ($children as $child) {
                scorm_get_preorder($preorder, $child);
            }
        }
    }
    return $preorder;
}

function scorm_find_common_ancestor($ancestors, $sco) {
    $pos = scorm_array_search('identifier', $sco->parent, $ancestors);
    if ($sco->parent != '/') {
        if ($pos === false) {
            return scorm_find_common_ancestor($ancestors, scorm_get_parent($sco));
        }
    }
    return $pos;
}

/* Usage
 Grab some XML data, either from a file, URL, etc. however you want. Assume storage in $strYourXML;

 $objXML = new xml2Array();
 $arroutput = $objXML->parse($strYourXML);
 print_r($arroutput); //print it out, or do whatever!

*/
class xml2Array {

    public $arroutput = array();
    public $resparser;
    public $strxmldata;

    /**
     * Convert a utf-8 string to html entities
     *
     * @param string $str The UTF-8 string
     * @return string
     */
    public function utf8_to_entities($str) {
        global $CFG;

        $entities = '';
        $values = array();
        $lookingfor = 1;

        return $str;
    }

    /**
     * Parse an XML text string and create an array tree that rapresent the XML structure
     *
     * @param string $strinputxml The XML string
     * @return array
     */
    public function parse($strinputxml) {
        $this->resparser = xml_parser_create ('UTF-8');
        xml_set_object($this->resparser, $this);
        xml_set_element_handler($this->resparser, "tagopen", "tagclosed");

        xml_set_character_data_handler($this->resparser, "tagdata");

        $this->strxmldata = xml_parse($this->resparser, $strinputxml );
        if (!$this->strxmldata) {
            die(sprintf("XML error: %s at line %d",
            xml_error_string(xml_get_error_code($this->resparser)),
            xml_get_current_line_number($this->resparser)));
        }

        xml_parser_free($this->resparser);

        return $this->arroutput;
    }

    public function tagopen($parser, $name, $attrs) {
        $tag = array("name" => $name, "attrs" => $attrs);
        array_push($this->arroutput, $tag);
    }

    public function tagdata($parser, $tagdata) {
        if (trim($tagdata)) {
            if (isset($this->arroutput[count($this->arroutput) - 1]['tagData'])) {
                $this->arroutput[count($this->arroutput) - 1]['tagData'] .= $this->utf8_to_entities($tagdata);
            } else {
                $this->arroutput[count($this->arroutput) - 1]['tagData'] = $this->utf8_to_entities($tagdata);
            }
        }
    }

    public function tagclosed($parser, $name) {
        $this->arroutput[count($this->arroutput) - 2]['children'][] = $this->arroutput[count($this->arroutput) - 1];
        array_pop($this->arroutput);
    }

}