<?php

$items = $page->children()->listed()->sortBy('published', 'desc');

$mapItem = function ($item) {
    return [
        'title'     => $item->title()->value(),
        'slug'      => $item->slug(),
        'published' => $item->published()->toDate('d/m/Y'),
        'intro'     => $item->intro()->value(),
        'cover'     => $item->cover()->toFile()?->url(),
    ];
};

$singleSlug = $items->count() === 1 ? $items->first()->slug() : null;

$specificData = [
    'intro'      => $page->intro()->value(),
    'items'      => $items->map($mapItem)->values(),
    'singleSlug' => $singleSlug,
];

$pageData = array_merge($genericData, $specificData);

header('Content-Type: application/json');
echo json_encode($pageData);