<?php

namespace App\Cursometr\Facts\CourseStructure;

use App\Cursometr\Facts\UsingQuery;
use Tinderbox\ClickhouseBuilder\Integrations\Laravel\Builder;
use Tinderbox\ClickhouseBuilder\Query\Identifier;

class CourseStructureLearnersTotalFact extends AbstractCourseStructureFact implements UsingQuery
{
    protected $format = 'integer';
    protected $defaultValue = 0;

    public static function getName(): string
    {
        return 'learners-total';
    }

    public function getQuery(\Closure $queryCallback = null): Builder
    {
        $learnersQuery = $this->getCleanQuery()
            ->table('learners')
            ->arrayJoin('entitiesAttempts')
            ->select('learnerId', 'entitiesAttempts.entityIri as entityIri')
            ->applyWherePeriod('entitiesAttempts.startedAt', $this->getPeriod())
            ->final();

        if (!is_null($queryCallback)) {
            $learnersQuery = $queryCallback($learnersQuery, $this);
        }

        $attemptsQuery = $this->getCleanQuery()
            ->from($learnersQuery)
            ->select('learnerId', 'entityIri as childEntityIri')
            ->where('learnerId', '>', 0);

        /*
         * Запрос на распаковывание таблицы с IRI
         */
        $longTableQuery = $this->getCleanQuery()
                               ->table(new Identifier($this->getTempTableName()))
                               ->select('entityIri', 'childEntityIri')
                               ->arrayJoin('childs as childEntityIri');

        $summaryJoinQuery = $this->getCleanQuery()
                             ->from($longTableQuery)
                             ->select('entityIri', 'learnerId')
                             ->allLeftJoin($attemptsQuery, ['childEntityIri']);

        $finalQuery = $this->getCleanQuery()
            ->from($summaryJoinQuery)
            ->select(raw('uniq(learnerId) as '.static::getIdentifier()), 'entityIri')
            ->where('learnerId', '>', 0)
            ->groupBy('entityIri');

        return $finalQuery;
    }

    public function getJoinColumns(): array
    {
        return ['entityIri'];
    }
}