My WP functions.php

functions.php

<?php

/* header menu */
register_nav_menu("menu", "Main menu");

/* footer menu */
register_nav_menu("menu_footer", "Footer menu");

/* thumbnails */
add_theme_support('post-thumbnails');

function my_get_post($post_id) {
    // Custom fields
    $ret['custom_fields'] = get_post_custom($post_id);

    // Content
    $content = get_extended(get_post_field('post_content', $post_id));
    $ret['content'] = [
        'title' => get_the_title($post_id),
        'main' => apply_filters('the_content', $content['main']),
        'extended' => apply_filters('the_content', $content['extended']),
    ];
    $ret['content_free'] = [
        'title' => get_the_title($post_id),
        'main' => $content['main'],
        'extended' => $content['extended'],
    ];

    // Images
    $ret['thumbnail'] = [
        'thumbnail' => get_the_post_thumbnail_url($post_id, 'thumbnail'),
        'medium' => get_the_post_thumbnail_url($post_id, 'medium'),
        'large' => get_the_post_thumbnail_url($post_id, 'large'),
        'full' => get_the_post_thumbnail_url($post_id, 'full'),
    ];

    // Media
    $thumbnail_id = get_post_thumbnail_id($post_id);
    $medias = get_attached_media('image', $post_id);
    foreach ($medias as $media) {
        if ($media->ID != $thumbnail_id) {
            $ret['media']['image'][] = [
                'thumbnail' => wp_get_attachment_image_src($media->ID, 'thumbnail')[0],
                'medium' => wp_get_attachment_image_src($media->ID, 'medium')[0],
                'large' => wp_get_attachment_image_src($media->ID, 'large')[0],
                'full' => wp_get_attachment_image_src($media->ID, 'full')[0],
                'excerpt' => $media->post_excerpt,
            ];
        }
    }

    return $ret;
}

function my_get_posts($post_type = 'post', $cat_id = 0, $tag = NULL) {
    $ret = [];
    $args = array(
        'numberposts' => -1,
        'category' => $cat_id,
        'orderby' => 'date',
        'order' => 'ASC',
        'include' => array(),
        'exclude' => array(),
        'meta_key' => '',
        'meta_value' => '',
        'post_type' => $post_type,
        'suppress_filters' => true,
        'tag' => $tag ? $tag : '',
    );
    $posts = get_posts($args);
    foreach ($posts as $post) {
        setup_postdata($post);
        $ret[$post->ID] = my_get_post($post->ID);
    }
    wp_reset_postdata();
    return $ret;
}