<?php
/**
 * สาธารณะ (ไม่ต้องล็อกอิน) — ส่งชุดคำถาม Quiz Battle โดม A/B/C ให้หน้าเล่น
 * ใช้เมื่อ /Game/api/quiz-settings ไม่ถึง Node (nginx ส่งแค่ static) แต่ยังเสิร์ฟ PHP ได้
 */
declare(strict_types=1);

header('Content-Type: application/json; charset=utf-8');
header('Cache-Control: no-store, no-cache, must-revalidate');
header('Pragma: no-cache');
header('X-Content-Type-Options: nosniff');

$allowedCats = [
    'cybercrime' => true,
    'cyber_law' => true,
    'privacy' => true,
    'digital_security' => true,
    'social_media' => true,
    'ethics' => true,
    'ai_data' => true,
];

$path = dirname(__DIR__) . '/data/quiz-settings.json';
$raw = @file_get_contents($path);
if ($raw === false || $raw === '') {
    echo json_encode(['battleQuizMcq' => []], JSON_UNESCAPED_UNICODE);
    exit;
}

$data = json_decode($raw, true);
if (!is_array($data)) {
    echo json_encode(['battleQuizMcq' => []], JSON_UNESCAPED_UNICODE);
    exit;
}

$src = $data['battleQuizMcq'] ?? [];
if (!is_array($src)) {
    echo json_encode(['battleQuizMcq' => []], JSON_UNESCAPED_UNICODE);
    exit;
}

$out = [];
foreach ($src as $q) {
    if (!is_array($q)) {
        continue;
    }
    $categoryId = trim((string)($q['categoryId'] ?? ''));
    if ($categoryId === '' || !isset($allowedCats[$categoryId])) {
        $categoryId = 'cybercrime';
    }
    $text = mb_substr(trim((string)($q['text'] ?? '')), 0, 500);
    if ($text === '') {
        continue;
    }
    $rawChoices = $q['choices'] ?? [];
    if (!is_array($rawChoices)) {
        continue;
    }
    $choices = [];
    for ($i = 0; $i < 3; $i++) {
        $choices[] = mb_substr(trim((string)($rawChoices[$i] ?? '')), 0, 160);
    }
    if (count($choices) !== 3 || in_array('', $choices, true)) {
        continue;
    }
    $ci = (int)($q['correctIndex'] ?? 0);
    if ($ci < 0 || $ci > 2) {
        $ci = 0;
    }
    $out[] = [
        'categoryId' => $categoryId,
        'text' => $text,
        'choices' => $choices,
        'correctIndex' => $ci,
    ];
    if (count($out) >= 200) {
        break;
    }
}

echo json_encode(['battleQuizMcq' => $out], JSON_UNESCAPED_UNICODE);