<?php
/* For licensing terms, see /license.txt */

class Cc13Convert
{
    /**
     * Converts a course object into a CC13 package and writes it to disk.
     *
     * @param \Chamilo\CourseBundle\Component\CourseCopy\Course $objCourse The Course object is "augmented" with info from the api_get_course_info() function, into the "$objCourse->info" array attribute.
     *
     * @throws Exception
     *
     * @return bool
     */
    public static function convert(string $packagedir, string $outdir, Chamilo\CourseBundle\Component\CourseCopy\Course $objCourse)
    {
        $dir = realpath($packagedir);
        if (empty($dir)) {
            throw new InvalidArgumentException('Directory does not exist!');
        }
        $odir = realpath($outdir);
        if (empty($odir)) {
            throw new InvalidArgumentException('Directory does not exist!');
        }

        if (!empty($objCourse)) {
            //Initialize the manifest metadata class
            $meta = new CcMetadataManifest();

            //Package metadata
            $metageneral = new CcMetadataGeneral();
            $metageneral->setLanguage($objCourse->info['language']);
            $metageneral->setTitle($objCourse->info['title'], $objCourse->info['language']);
            $metageneral->setDescription('', $objCourse->info['language']);
            $metageneral->setCatalog('category');
            $metageneral->setEntry($objCourse->info['categoryName']);
            $meta->addMetadataGeneral($metageneral);

            // Create the manifest
            $manifest = new CcManifest();

            $manifest->addMetadataManifest($meta);

            $organization = null;

            //Get the course structure - this will be transformed into organization
            //Step 1 - Get the list and order of sections/topics

            $count = 1;
            $sections = [];
            $resources = $objCourse->resources;

            // We check the quiz sections
            if (isset($resources['quiz'])) {
                $quizSections = self::getItemSections(
                    $resources['quiz'], // array of quiz IDs generated by the course backup process
                    'quiz',
                    $count,
                    $objCourse->info['code'],
                    $resources[RESOURCE_QUIZQUESTION] // selected question IDs from the course export form
                );
                $sections = array_merge($sections, $quizSections);
            }

            // We check the document sections
            if (isset($resources['document'])) {
                $documentSections = self::getItemSections(
                    $resources['document'],
                    'document',
                    $count,
                    $objCourse->info['code']
                );
                $sections = array_merge($sections, $documentSections);
            }

            // We check the wiki sections
            if (isset($resources['wiki'])) {
                $wikiSections = self::getItemSections(
                    $resources['wiki'],
                    'wiki',
                    $count,
                    $objCourse->info['code']
                );
                $sections = array_merge($sections, $wikiSections);
            }

            // We check the forum sections
            if (isset($resources['forum'])) {
                $forumSections = self::getItemSections(
                    $resources['forum'],
                    'forum',
                    $count,
                    $objCourse->info['code'],
                    $resources['Forum_Category']
                );
                $sections = array_merge($sections, $forumSections);
            }

            // We check the link sections
            if (isset($resources['link'])) {
                $linkSections = self::getItemSections(
                    $resources['link'],
                    'link',
                    $count,
                    $objCourse->info['code'],
                    $resources['Link_Category']
                );
                $sections = array_merge($sections, $linkSections);
            }

            //organization title
            $organization = new CcOrganization();
            foreach ($sections as $sectionid => $values) {
                $item = new CcItem();
                $item->title = $values[0];
                self::processSequence($item, $manifest, $values[1], $dir, $odir);
                $organization->addItem($item);
            }
            $manifest->putNodes();

            if (!empty($organization)) {
                $manifest->addNewOrganization($organization);
            }

            $manifestpath = $outdir.DIRECTORY_SEPARATOR.'imsmanifest.xml';
            $saved = $manifest->saveTo($manifestpath);

            return $saved;
        }

        return false;
    }

    /**
     * Return array of type $sections[1]['quiz', [sequence]] where sequence is the result of a call to getSequence().
     *
     * @param string $courseCode     The course code litteral
     * @param ?array $itmesExtraData If defined, represents the items IDs selected in the course export form
     *
     * @return array
     * @reference self::getSequence()
     */
    protected static function getItemSections(array $itemData, string $itemType, int &$count, string $courseCode, ?array $itmesExtraData = null)
    {
        $sections = [];
        switch ($itemType) {
            case 'quiz':
            case 'document':
            case 'wiki':
                $convertType = $itemType;
                if ($itemType == 'wiki') {
                    $convertType = 'Page';
                }
                $sectionid = $count;
                $sectiontitle = ucfirst($itemType);
                $sequence = self::getSequence($itemData, 0, $convertType, $courseCode, $itmesExtraData);
                $sections[$sectionid] = [$sectiontitle, $sequence];
                $count++;
                break;
            case 'link':
                $links = self::getSequence($itemData, null, $itemType);
                foreach ($links as $categoryId => $sequence) {
                    $sectionid = $count;
                    if (isset($itmesExtraData[$categoryId])) {
                        $sectiontitle = $itmesExtraData[$categoryId]->title;
                    } else {
                        $sectiontitle = 'General';
                    }
                    $sections[$sectionid] = [$sectiontitle, $sequence];
                    $count++;
                }
                break;
            case 'forum':
                if (isset($itmesExtraData)) {
                    foreach ($itmesExtraData as $fcategory) {
                        if (isset($fcategory->obj)) {
                            $objCategory = $fcategory->obj;
                            $sectionid = $count;
                            $sectiontitle = $objCategory->cat_title;
                            $sequence = self::getSequence($itemData, $objCategory->iid, $itemType);
                            $sections[$sectionid] = [$sectiontitle, $sequence];
                            $count++;
                        }
                    }
                }
                break;
        }

        return $sections;
    }

    /**
     * Return array of items by category and item ID ("test" level, not "question" level) with details like title,
     * comment (description), type, questions, max_attempt, etc.
     *
     * @param array   $objItems      Array of item objects as returned by the course backup code
     * @param ?int    $categoryId
     * @param ?string $itemType
     * @param ?string $coursecode
     * @param ?array  $itemQuestions
     *
     * @return array|mixed
     */
    protected static function getSequence(array $objItems, ?int $categoryId = null, ?string $itemType = null, ?string $coursecode = null, ?array $itemQuestions = null)
    {
        $sequences = [];
        switch ($itemType) {
            case 'quiz':
                $sequence = [];
                foreach ($objItems as $objItem) {
                    if ($categoryId === 0) {
                        $questions = [];
                        foreach ($objItem->obj->question_ids as $questionId) {
                            if (isset($itemQuestions[$questionId])) {
                                $questions[$questionId] = $itemQuestions[$questionId];
                            }
                        }
                        // As weird as this may sound, the constructors for the different object types (found in
                        // src/CourseBundle/Component/CourseCopy/Resources/[objecttype].php) store the object property
                        // in the "obj" attribute. Old code...
                        // So here we recover properties from the quiz object, including questions (array built above).
                        $sequence[$categoryId][$objItem->obj->iid] = [
                            'title' => $objItem->obj->title,
                            'comment' => $objItem->obj->description,
                            'cc_type' => 'quiz',
                            'source_id' => $objItem->obj->iid,
                            'questions' => $questions,
                            'max_attempt' => $objItem->obj->max_attempt,
                            'expired_time' => $objItem->obj->expired_time,
                            'pass_percentage' => $objItem->obj->pass_percentage,
                            'random_answers' => $objItem->obj->random_answers,
                            'course_code' => $coursecode,
                        ];
                    }
                }
                $sequences = $sequence[$categoryId];
                break;
            case 'document':
                $sequence = [];
                foreach ($objItems as $objItem) {
                    if ($categoryId === 0) {
                        $sequence[$categoryId][$objItem->source_id] = [
                            'title' => $objItem->title,
                            'comment' => $objItem->comment,
                            'cc_type' => ($objItem->file_type == 'folder' ? 'folder' : 'resource'),
                            'source_id' => $objItem->source_id,
                            'path' => $objItem->path,
                            'file_type' => $objItem->file_type,
                            'course_code' => $coursecode,
                        ];
                    }
                }
                $sequences = $sequence[$categoryId];
                break;
            case 'forum':
                foreach ($objItems as $objItem) {
                    if ($categoryId == $objItem->obj->forum_category) {
                        $sequence[$categoryId][$objItem->obj->forum_id] = [
                            'title' => $objItem->obj->forum_title,
                            'comment' => $objItem->obj->forum_comment,
                            'cc_type' => 'forum',
                            'source_id' => $objItem->obj->iid,
                        ];
                    }
                }
                $sequences = $sequence[$categoryId];
                break;
            case 'page':
                foreach ($objItems as $objItem) {
                    if ($categoryId === 0) {
                        $sequence[$categoryId][$objItem->page_id] = [
                            'title' => $objItem->title,
                            'comment' => $objItem->content,
                            'cc_type' => 'page',
                            'source_id' => $objItem->page_id,
                            'reflink' => $objItem->reflink,
                        ];
                    }
                }
                $sequences = $sequence[$categoryId];
                break;
            case 'link':
                if (!isset($categoryId)) {
                    $categories = [];
                    foreach ($objItems as $objItem) {
                        $categories[$objItem->category_id] = self::getSequence($objItems, $objItem->category_id, $itemType);
                    }
                    $sequences = $categories;
                } else {
                    foreach ($objItems as $objItem) {
                        if ($categoryId == $objItem->category_id) {
                            $sequence[$categoryId][$objItem->source_id] = [
                                'title' => $objItem->title,
                                'comment' => $objItem->description,
                                'cc_type' => 'url',
                                'source_id' => $objItem->source_id,
                                'url' => $objItem->url,
                                'target' => $objItem->target,
                            ];
                        }
                    }
                    $sequences = $sequence[$categoryId];
                }
                break;
        }

        return $sequences;
    }

    /**
     * Process the different types of activities exported from the course.
     * When dealing with tests, the "sequence" provided here is a test, not a question.
     * For each sequence, call the corresponding CcConverter[Type] object instantiation method in export/src/converter/.
     *
     * @return void
     */
    protected static function processSequence(CcIItem &$item, CcIManifest &$manifest, array $sequence, string $packageroot, string $outdir)
    {
        if (!empty($sequence)) {
            foreach ($sequence as $seq) {
                $activity_type = ucfirst($seq['cc_type']);
                $activity_indentation = 0;
                $aitem = self::itemIndenter($item, $activity_indentation);
                $caller = "CcConverter{$activity_type}";
                if (class_exists($caller)) {
                    $obj = new $caller($aitem, $manifest, $packageroot, $outdir);
                    if (!$obj->convert($outdir, $seq)) {
                        throw new RuntimeException("failed to convert {$activity_type}");
                    }
                }
            }
        }
    }

    protected static function itemIndenter(CcIItem &$item, $level = 0)
    {
        $indent = (int) $level;
        $indent = ($indent) <= 0 ? 0 : $indent;
        $nprev = null;
        $nfirst = null;
        for ($pos = 0, $size = $indent; $pos < $size; $pos++) {
            $nitem = new CcItem();
            $nitem->title = '';
            if (empty($nfirst)) {
                $nfirst = $nitem;
            }
            if (!empty($nprev)) {
                $nprev->addChildItem($nitem);
            }
            $nprev = $nitem;
        }
        $result = $item;
        if (!empty($nfirst)) {
            $item->addChildItem($nfirst);
            $result = $nprev;
        }

        return $result;
    }
}