<?php

declare(strict_types=1);

namespace Evomedien\FeComment\Service;

use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Frontend\Authentication\FrontendUserAuthentication;

/**
 * The fe_comment state of the current frontend user - ONE implementation
 * for both consumers (2026-10-09): GET /api/fe-comment/state and the
 * "Feedback Overview" content element in the page JSON. Who is allowed,
 * the open summary with its items and attachments, recipients, overview URL.
 */
final class FeedbackState
{
    private const T_SUMMARY = 'tx_fecomment_summary';
    private const T_FEEDBACK = 'tx_fecomment_feedback';

    private readonly ExtensionSettings $settings;

    public function __construct(?ExtensionSettings $settings = null)
    {
        $this->settings = $settings ?? GeneralUtility::makeInstance(ExtensionSettings::class);
    }

    /**
     * The logged-in frontend user when the extension is enabled and the user
     * belongs to the configured group; null otherwise.
     *
     * @return array{uid:int,username:string,name:string,email:string}|null
     */
    public function allowedUser(ServerRequestInterface $request): ?array
    {
        if (!$this->settings->enabled()) {
            return null;
        }
        $frontendUser = $request->getAttribute('frontend.user');
        if (!$frontendUser instanceof FrontendUserAuthentication || empty($frontendUser->user['uid'])) {
            return null;
        }
        $requiredGroup = $this->settings->feUserGroup();
        if ($requiredGroup > 0) {
            $groups = GeneralUtility::intExplode(',', (string)($frontendUser->user['usergroup'] ?? ''), true);
            if (!in_array($requiredGroup, $groups, true)) {
                return null;
            }
        }
        return [
            'uid' => (int)$frontendUser->user['uid'],
            'username' => (string)($frontendUser->user['username'] ?? ''),
            'name' => trim((string)($frontendUser->user['name'] ?? '')) ?: (string)($frontendUser->user['username'] ?? ''),
            'email' => (string)($frontendUser->user['email'] ?? ''),
        ];
    }

    /**
     * The state payload: `{allowed: false}` for everyone not allowed, the full
     * shape otherwise.
     *
     * @param array{uid:int,username:string,name:string,email:string}|null $user
     * @return array<string,mixed>
     */
    public function payload(?array $user): array
    {
        if ($user === null) {
            return ['allowed' => false];
        }
        $summary = $this->openSummary($user['uid'], false);
        $summaryPayload = $summary === null ? null : $this->summaryPayload($summary);
        $hasContent = $summaryPayload !== null
            && ($summaryPayload['items'] !== [] || trim(strip_tags($summaryPayload['generalNotes'])) !== '');
        return [
            'allowed' => true,
            'user' => ['name' => $user['name'], 'email' => $user['email']],
            'recipients' => $this->recipientOptions(),
            'overviewUrl' => $this->overviewUrl(),
            'summary' => $summaryPayload,
            // the submit button may be active (the endpoint rejects an empty summary)
            'canSubmit' => $hasContent,
            'actions' => self::ACTIONS,
        ];
    }

    /**
     * The write endpoints, delivered with the state so a front end needs no
     * hard-coded URLs ({uid}/{refUid} are placeholders). All POST, JSON
     * bodies except `upload` (multipart: file + feedback).
     */
    private const ACTIONS = [
        'submit' => ['method' => 'POST', 'url' => '/api/fe-comment/submit'],
        'updateSummary' => ['method' => 'POST', 'url' => '/api/fe-comment/summary', 'body' => ['generalNotes' => 'html', 'recipients' => 'int[]']],
        'createItem' => ['method' => 'POST', 'url' => '/api/fe-comment/feedback', 'body' => ['url' => 'string', 'note' => 'html']],
        'updateItem' => ['method' => 'POST', 'url' => '/api/fe-comment/feedback/{uid}', 'body' => ['url' => 'string', 'note' => 'html']],
        'deleteItem' => ['method' => 'POST', 'url' => '/api/fe-comment/feedback/{uid}/delete'],
        'upload' => ['method' => 'POST', 'url' => '/api/fe-comment/upload', 'body' => ['file' => 'multipart', 'feedback' => 'int']],
        'deleteAttachment' => ['method' => 'POST', 'url' => '/api/fe-comment/attachment/{refUid}/delete'],
    ];

    /** @return array<string,mixed>|null the user's open summary row */
    public function openSummary(int $userUid, bool $createIfMissing): ?array
    {
        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable(self::T_SUMMARY);
        $summary = $connection->fetchAssociative(
            'SELECT * FROM ' . self::T_SUMMARY . " WHERE deleted = 0 AND status = 'open' AND fe_user = ? ORDER BY uid DESC",
            [$userUid]
        );
        if ($summary) {
            return $summary;
        }
        if (!$createIfMissing) {
            return null;
        }
        $connection->insert(self::T_SUMMARY, [
            'pid' => $this->settings->storagePid(),
            'tstamp' => time(),
            'crdate' => time(),
            'fe_user' => $userUid,
            'status' => 'open',
        ]);
        return $this->openSummary($userUid, false);
    }

    /**
     * @param array<string,mixed> $summary
     * @return array{uid:int,generalNotes:string,recipients:int[],items:array<int,array{uid:int,url:string,note:string,attachments:array<int,array{refUid:int,name:string,url:string}>}>}
     */
    public function summaryPayload(array $summary): array
    {
        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable(self::T_FEEDBACK);
        $items = [];
        foreach ($connection->fetchAllAssociative(
            'SELECT uid, url, note FROM ' . self::T_FEEDBACK . ' WHERE deleted = 0 AND summary = ? ORDER BY sorting',
            [(int)$summary['uid']]
        ) as $row) {
            $items[] = [
                'uid' => (int)$row['uid'],
                'url' => (string)$row['url'],
                'note' => (string)$row['note'],
                'attachments' => $this->attachments((int)$row['uid']),
            ];
        }
        return [
            'uid' => (int)$summary['uid'],
            'generalNotes' => (string)($summary['general_notes'] ?? ''),
            'recipients' => GeneralUtility::intExplode(',', (string)($summary['recipients'] ?? ''), true),
            'items' => $items,
        ];
    }

    /** @return array<int,array{refUid:int,name:string,url:string}> */
    private function attachments(int $feedbackUid): array
    {
        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable('sys_file_reference');
        $rows = $connection->fetchAllAssociative(
            'SELECT r.uid AS ref_uid, f.name, f.identifier FROM sys_file_reference r
             JOIN sys_file f ON f.uid = r.uid_local
             WHERE r.deleted = 0 AND r.tablenames = ? AND r.fieldname = ? AND r.uid_foreign = ? ORDER BY r.uid',
            [self::T_FEEDBACK, 'attachments', $feedbackUid]
        );
        return array_map(static fn(array $r): array => [
            'refUid' => (int)$r['ref_uid'],
            'name' => (string)$r['name'],
            'url' => '/fileadmin' . $r['identifier'],
        ], $rows);
    }

    /** @return array<int,array{id:int,label:string}> */
    private function recipientOptions(): array
    {
        $options = [];
        foreach ($this->settings->recipients() as $id => $recipient) {
            $options[] = ['id' => $id, 'label' => $recipient['label']];
        }
        return $options;
    }

    /**
     * Visitor-facing URL of the feedback overview page (extension setting
     * overviewPid), resolved via the page slug. Empty string when unset.
     */
    private function overviewUrl(): string
    {
        $pid = $this->settings->overviewPid();
        if ($pid <= 0) {
            return '';
        }
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('pages');
        $slug = $queryBuilder->select('slug')->from('pages')
            ->where($queryBuilder->expr()->eq('uid', $queryBuilder->createNamedParameter($pid, \Doctrine\DBAL\ParameterType::INTEGER)))
            ->executeQuery()->fetchOne();
        return is_string($slug) ? $slug : '';
    }
}