<?php

declare(strict_types=1);

namespace Mummert\SurveyBundle\Repository;

use Contao\CoreBundle\Framework\ContaoFramework;
use Contao\StringUtil;
use Doctrine\DBAL\ArrayParameterType;
use Doctrine\DBAL\Connection;
use Mummert\SurveyBundle\Model\SurveyModel;

final class SurveyRepository
{
    private ?bool $hasListMetadataColumns = null;

    public function __construct(
        private readonly Connection $connection,
        private readonly ContaoFramework $framework,
    ) {
    }

    public function findById(int $id): ?SurveyModel
    {
        $adapter = $this->framework->getAdapter(SurveyModel::class);
        $model = $adapter->findByPk($id);

        return $model instanceof SurveyModel ? $model : null;
    }

    public function findByPublicAlias(string $alias, bool $publishedOnly = true): ?SurveyModel
    {
        $qb = $this->connection->createQueryBuilder();
        $qb
            ->select('id')
            ->from('tl_survey')
            ->where('alias = :alias')
            ->setParameter('alias', $alias)
            ->setMaxResults(1)
        ;

        if ($publishedOnly) {
            $qb->andWhere('published = 1');
            $qb->andWhere('isActive = 1');
        }

        $id = $qb->executeQuery()->fetchOne();

        if (false === $id) {
            return null;
        }

        return $this->findById((int) $id);
    }

    /**
     * @return list<array<string, mixed>>
     */
    public function findEditableByMember(int $memberId): array
    {
        return $this->connection->fetchAllAssociative(
            <<<'SQL'
                SELECT
                    s.id,
                    s.title,
                    s.alias,
                    s.description,
                    s.published,
                    s.isActive,
                    s.isLocked,
                    s.updatedAt,
                    COUNT(DISTINCT q.id) AS questionCount,
                    COUNT(DISTINCT CASE WHEN sub.isFinished = 1 THEN sub.id END) AS participationCount
                FROM tl_survey s
                INNER JOIN tl_survey_editor e ON COALESCE(NULLIF(e.survey, 0), e.pid) = s.id AND e.member = :member
                LEFT JOIN tl_survey_content q ON q.pid = s.id
                LEFT JOIN tl_survey_submission sub ON sub.survey = s.id
                GROUP BY s.id
                ORDER BY s.updatedAt DESC, s.title ASC
            SQL,
            ['member' => $memberId],
        );
    }

    public function create(int $memberId, array $data): SurveyModel
    {
        $now = time();
        $title = trim((string) ($data['title'] ?? 'Neue Umfrage'));

        $this->connection->insert('tl_survey', [
            'tstamp' => $now,
            'title' => $title,
            'alias' => $this->ensurePublicAlias(null),
            'category' => serialize($this->normalizeCategoryIds($data['category'] ?? [])),
            'description' => (string) ($data['description'] ?? ''),
            'published' => '',
            'isActive' => '',
            'isLocked' => '',
            'createdBy' => $memberId,
            'updatedBy' => $memberId,
            'createdAt' => $now,
            'updatedAt' => $now,
        ]);

        $id = (int) $this->connection->lastInsertId();
        $this->refreshListMetadata($id);

        return $this->findById($id) ?? throw new \RuntimeException('Umfrage konnte nicht angelegt werden.');
    }

    public function update(SurveyModel $survey, int $memberId, array $data): void
    {
        $title = trim((string) ($data['title'] ?? $survey->title));

        $this->connection->update('tl_survey', [
            'tstamp' => time(),
            'title' => $title,
            'alias' => $this->ensurePublicAlias((string) $survey->alias, (int) $survey->id),
            'category' => serialize($this->normalizeCategoryIds($data['category'] ?? StringUtil::deserialize($survey->category, true))),
            'description' => (string) ($data['description'] ?? $survey->description),
            'published' => array_key_exists('published', $data) ? (!empty($data['published']) ? '1' : '') : (string) $survey->published,
            'isActive' => array_key_exists('isActive', $data) ? (!empty($data['isActive']) ? '1' : '') : (string) ($survey->isActive ?? ''),
            'updatedBy' => $memberId,
            'updatedAt' => time(),
        ], [
            'id' => (int) $survey->id,
        ]);

        $this->refreshListMetadata((int) $survey->id);
    }

    public function ensurePublicAlias(?string $alias, int $excludeId = 0): string
    {
        $candidate = strtolower(trim((string) $alias));

        if ($this->isValidPublicAlias($candidate) && !$this->aliasExists($candidate, $excludeId)) {
            return $candidate;
        }

        do {
            $candidate = $this->generateRandomPublicAlias();
        } while ($this->aliasExists($candidate, $excludeId));

        return $candidate;
    }

    /**
     * @param list<int> $categoryIds
     */
    public function updateCategories(int $surveyId, array $categoryIds): void
    {
        $this->connection->update('tl_survey', [
            'category' => serialize($this->normalizeCategoryIds($categoryIds)),
            'tstamp' => time(),
            'updatedAt' => time(),
        ], [
            'id' => $surveyId,
        ]);

        $this->refreshListMetadata($surveyId);
    }

    public function refreshListMetadata(int $surveyId): void
    {
        if (!$this->hasListMetadataColumns()) {
            return;
        }

        $survey = $this->findById($surveyId);

        if (!$survey instanceof SurveyModel) {
            return;
        }

        $categoryIds = $this->normalizeCategoryIds($survey->category);
        $categoryTitles = $this->fetchCategoryTitles($categoryIds);
        $assignedMembers = $this->fetchAssignedMembers($surveyId);
        $memberIds = [];
        $memberNames = [];

        foreach ($assignedMembers as $assignedMember) {
            $memberIds[] = (int) $assignedMember['id'];
            $memberNames[] = (string) $assignedMember['name'];
        }

        $this->connection->update('tl_survey', [
            'categoryFilter' => implode(',', $categoryIds),
            'categorySummary' => implode(', ', $categoryTitles),
            'templateFilter' => '1' === (string) $survey->isTemplate ? '1' : '0',
            'templateSummary' => '1' === (string) $survey->isTemplate ? 'Ja' : 'Nein',
            'assignedMembersFilter' => implode(',', $memberIds),
            'assignedMembersSummary' => implode(', ', $memberNames),
        ], [
            'id' => $surveyId,
        ]);
    }

    public function touch(int $surveyId): void
    {
        $now = time();

        $this->connection->update('tl_survey', [
            'tstamp' => $now,
            'updatedAt' => $now,
        ], [
            'id' => $surveyId,
        ]);
    }

    public function lock(int $surveyId): void
    {
        $this->connection->update('tl_survey', [
            'isLocked' => '1',
            'tstamp' => time(),
            'updatedAt' => time(),
        ], [
            'id' => $surveyId,
        ]);
    }

    public function publish(int $surveyId, int $memberId): void
    {
        $now = time();

        $this->connection->update('tl_survey', [
            'published' => '1',
            'isActive' => '1',
            'isLocked' => '1',
            'tstamp' => $now,
            'updatedBy' => $memberId,
            'updatedAt' => $now,
        ], [
            'id' => $surveyId,
        ]);
    }

    public function setActive(int $surveyId, int $memberId, bool $isActive): void
    {
        $now = time();

        $this->connection->update('tl_survey', [
            'isActive' => $isActive ? '1' : '',
            'tstamp' => $now,
            'updatedBy' => $memberId,
            'updatedAt' => $now,
        ], [
            'id' => $surveyId,
        ]);
    }

    public function deleteCascade(int $surveyId): void
    {
        $this->connection->transactional(function () use ($surveyId): void {
            $submissionIds = array_values(array_map('intval', $this->connection->fetchFirstColumn(
                'SELECT id FROM tl_survey_submission WHERE survey = ?',
                [$surveyId],
            )));

            if ([] !== $submissionIds) {
                $this->connection->executeStatement(
                    'DELETE FROM tl_survey_answer WHERE submission IN (?)',
                    [$submissionIds],
                    [ArrayParameterType::INTEGER],
                );
            }

            $this->connection->delete('tl_survey_submission', ['survey' => $surveyId]);
            $this->connection->delete('tl_survey_condition', ['pid' => $surveyId]);
            $this->connection->delete('tl_survey_content', ['pid' => $surveyId]);
            $this->connection->delete('tl_survey_editor', ['survey' => $surveyId]);
            $this->connection->delete('tl_survey_editor', ['pid' => $surveyId]);
            $this->connection->delete('tl_survey', ['id' => $surveyId]);
        });
    }

    private function generateRandomPublicAlias(): string
    {
        $characters = 'abcdefghijklmnopqrstuvwxyz0123456789';
        $alias = '';

        for ($index = 0; $index < 20; ++$index) {
            $alias .= $characters[random_int(0, strlen($characters) - 1)];
        }

        return $alias;
    }

    private function aliasExists(string $alias, int $excludeId = 0): bool
    {
        $qb = $this->connection->createQueryBuilder();
        $qb
            ->select('id')
            ->from('tl_survey')
            ->where('alias = :alias')
            ->setParameter('alias', $alias)
            ->setMaxResults(1)
        ;

        if ($excludeId > 0) {
            $qb
                ->andWhere('id != :excludeId')
                ->setParameter('excludeId', $excludeId)
            ;
        }

        return false !== $qb->executeQuery()->fetchOne();
    }

    /**
     * @param list<int> $categoryIds
     *
     * @return list<string>
     */
    private function fetchCategoryTitles(array $categoryIds): array
    {
        if ([] === $categoryIds) {
            return [];
        }

        $placeholders = implode(',', array_fill(0, count($categoryIds), '?'));
        $rows = $this->connection->fetchAllAssociative(
            sprintf('SELECT id, title FROM tl_survey_category WHERE id IN (%s)', $placeholders),
            $categoryIds,
        );
        $titlesById = [];

        foreach ($rows as $row) {
            $titlesById[(int) $row['id']] = (string) $row['title'];
        }

        $titles = [];

        foreach ($categoryIds as $categoryId) {
            if (isset($titlesById[$categoryId])) {
                $titles[] = $titlesById[$categoryId];
            }
        }

        return $titles;
    }

    /**
     * @return list<array{id:int,name:string}>
     */
    private function fetchAssignedMembers(int $surveyId): array
    {
        $rows = $this->connection->fetchAllAssociative(
            <<<'SQL'
                SELECT DISTINCT
                    m.id,
                    m.firstname,
                    m.lastname,
                    m.email
                FROM tl_survey_editor e
                INNER JOIN tl_member m ON m.id = e.member
                WHERE COALESCE(NULLIF(e.survey, 0), e.pid) = ?
                ORDER BY m.lastname ASC, m.firstname ASC, m.email ASC
            SQL,
            [$surveyId],
        );
        $members = [];

        foreach ($rows as $row) {
            $name = trim(sprintf('%s %s', (string) $row['firstname'], (string) $row['lastname']));
            $members[] = [
                'id' => (int) $row['id'],
                'name' => '' !== $name ? $name : (string) $row['email'],
            ];
        }

        return $members;
    }

    private function hasListMetadataColumns(): bool
    {
        if (null !== $this->hasListMetadataColumns) {
            return $this->hasListMetadataColumns;
        }

        $columnNames = array_map(
            static fn (string $columnName): string => strtolower($columnName),
            array_keys($this->connection->createSchemaManager()->listTableColumns('tl_survey')),
        );

        return $this->hasListMetadataColumns = !array_diff(
            ['categoryfilter', 'categorysummary', 'templatefilter', 'templatesummary', 'assignedmembersfilter', 'assignedmemberssummary'],
            $columnNames,
        );
    }

    private function isValidPublicAlias(string $alias): bool
    {
        return 1 === preg_match('/^[a-z0-9]{20}$/', $alias);
    }

    /**
     * @return list<int>
     */
    private function normalizeCategoryIds(mixed $value): array
    {
        $categoryIds = is_array($value) ? $value : StringUtil::deserialize($value, true);
        $categoryIds = array_values(array_unique(array_filter(array_map('intval', $categoryIds), static fn (int $id): bool => $id > 0)));
        sort($categoryIds);

        return $categoryIds;
    }
}