// 本文中の全画像を、ご提示の ImageObject 形式で独立出力（配列を直出し）
add_action('wp_head', function () {
    if (!is_singular('post')) return;
    global $post;
    if (empty($post)) return;

    $content = apply_filters('the_content', $post->post_content);
    if (!$content) return;

    $images = mysite_extract_images_from_content($content);
    if (empty($images)) return;

    // 既定値（必要に応じて編集）
    $license_page   = get_permalink($post);                 // 例：記事詳細をライセンス案内ページにする
    $copyright_year = date_i18n('Y');                       // 例：今年
    $default_credit = 'FANZA';                                   // 例："FANZA" など固定したい場合に設定

    $jsonld_images = [];

    foreach ($images as $img) {
        // name / caption の作り方：title/figcaption/alt から生成済み値を利用
        $name    = $img['caption'] ?: $img['description'] ?: '';
        $caption = $img['caption'] ?: $img['description'] ?: '';

        // creditText / creator はドメインから推測 or 既定値
        $brand = $default_credit ?: mysite_brand_from_url($img['url']);

        $obj = [
            '@context'           => 'https://schema.org',
            '@type'              => 'ImageObject',
            'contentUrl'         => $img['url'],
            'url'                => $img['url'],
        ];

        if ($name)                 $obj['name']               = $name;
        if ($caption)              $obj['caption']            = $caption;
        if (!empty($img['license'])) {
            $obj['license'] = $img['license'];
        } else {
            // 明示ライセンスが取れない場合はサイト側の案内ページを設定（不要なら削除）
            $obj['license'] = $license_page;
        }

        if ($brand) {
            $obj['creditText'] = $brand;
            $obj['creator']    = ['@type' => 'Organization', 'name' => $brand];
            $obj['copyrightNotice'] = '© ' . $copyright_year . ' ' . $brand;
        }

        // 取得できれば acquisition ページ（= ライセンス案内ページでもOK）
        $obj['acquireLicensePage'] = $license_page;

        // 参考情報（任意）
        if (!empty($img['thumbnailUrl'])) $obj['thumbnailUrl'] = $img['thumbnailUrl'];
        if (!empty($img['uploadDate']))   $obj['uploadDate']   = $img['uploadDate'];
        if (!empty($img['width']))        $obj['width']        = (int)$img['width'];
        if (!empty($img['height']))       $obj['height']       = (int)$img['height'];

        $jsonld_images[] = $obj;

        if (count($jsonld_images) >= 50) break; // 上限
    }

    // 配列のまま <script> に直出し
    echo "\n<script type=\"application/ld+json\">\n";
    echo wp_json_encode($jsonld_images, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
    echo "\n</script>\n";
}, 100);

/* ---------- 画像抽出（前提ユーティリティ） ---------- */

function mysite_extract_images_from_content(string $content): array {
    $html = '<meta http-equiv="Content-Type" content="text/html; charset=utf-8">' . $content;
    $dom  = new DOMDocument();
    libxml_use_internal_errors(true);
    $dom->loadHTML(mb_convert_encoding($html, 'HTML-ENTITIES', 'UTF-8'));
    libxml_clear_errors();

    $xpath = new DOMXPath($dom);
    $img_nodes = $xpath->query('//img');

    $out = [];
    $seen = [];

    foreach ($img_nodes as $img) {
        /** @var DOMElement $img */
        $url = mysite_pick_img_url($img);
        if (!$url) continue;

        $url = mysite_make_absolute_url($url);
        if (!$url) continue;

        $key = md5($url);
        if (isset($seen[$key])) continue;
        $seen[$key] = true;

        $caption = mysite_find_figcaption($img) ?: trim($img->getAttribute('title'));
        $alt     = trim($img->getAttribute('alt'));
        $description = $alt ?: $caption;

        $width  = $img->getAttribute('width') ?: null;
        $height = $img->getAttribute('height') ?: null;

        $thumb  = null;
        $upload = null;

        $attachment_id = function_exists('attachment_url_to_postid') ? attachment_url_to_postid($url) : 0;
        if ($attachment_id) {
            if (!$width || !$height) {
                $meta = wp_get_attachment_metadata($attachment_id);
                if (!empty($meta['width']))  $width  = $meta['width'];
                if (!empty($meta['height'])) $height = $meta['height'];
            }
            $thumb_src = wp_get_attachment_image_src($attachment_id, 'thumbnail');
            if (!empty($thumb_src[0])) $thumb = $thumb_src[0];

            $att_post = get_post($attachment_id);
            if ($att_post && !is_wp_error($att_post)) {
                $upload = get_date_from_gmt(gmdate('Y-m-d H:i:s', strtotime($att_post->post_date_gmt)), 'c');
                if (empty($caption) && !empty($att_post->post_excerpt))  $caption = wp_strip_all_tags($att_post->post_excerpt);
                if (empty($description) && !empty($att_post->post_content)) $description = wp_strip_all_tags($att_post->post_content);
            }
        }

        $out[] = array_filter([
            'url'          => $url,
            'caption'      => $caption ?: null,
            'description'  => $description ?: null,
            'width'        => $width ? (int)$width : null,
            'height'       => $height ? (int)$height : null,
            'thumbnailUrl' => $thumb,
            'uploadDate'   => $upload,
            // 任意：投稿やメディアのカスタムフィールドから license を拾うならここで設定
            // 'license'    => get_post_meta($attachment_id, 'license_url', true) ?: null,
        ], fn($v) => $v !== null && $v !== '');

        if (count($out) >= 50) break;
    }
    return $out;
}

function mysite_pick_img_url(DOMElement $img): ?string {
    $candidates = [
        $img->getAttribute('src'),
        $img->getAttribute('data-src'),
        $img->getAttribute('data-lazy-src'),
        $img->getAttribute('data-original'),
    ];
    $srcset = $img->getAttribute('srcset');
    if ($srcset) {
        $parts = array_map('trim', explode(',', $srcset));
        if (!empty($parts[0])) {
            $first = trim(explode(' ', $parts[0])[0]);
            $candidates[] = $first;
        }
    }
    foreach ($candidates as $u) {
        if ($u && stripos($u, 'data:') !== 0) return $u;
    }
    return null;
}

function mysite_find_figcaption(DOMElement $img): ?string {
    $parent = $img->parentNode;
    while ($parent && $parent instanceof DOMElement) {
        if (strtolower($parent->nodeName) === 'figure') {
            foreach ($parent->childNodes as $child) {
                if ($child instanceof DOMElement && strtolower($child->nodeName) === 'figcaption') {
                    return trim(preg_replace('/\s+/', ' ', $child->textContent));
                }
            }
            break;
        }
        $parent = $parent->parentNode;
    }
    return null;
}

function mysite_make_absolute_url(string $url): ?string {
    if (!$url) return null;
    if (preg_match('~^https?://~i', $url)) return $url;

    $home = rtrim(home_url('/'), '/');
    if (strpos($url, '//') === 0) {
        $scheme = parse_url($home, PHP_URL_SCHEME) ?: 'https';
        return $scheme . ':' . $url;
    }
    if ($url[0] === '/') return $home . $url;
    $base = rtrim(get_permalink(), '/');
    return $base . '/' . ltrim($url, './');
}

/**
 * 画像URLのドメインから簡易的にブランド名を推定
 * 例）"https://doujin-assets.dmm.co.jp/..." -> "dmm.co.jp" -> "DMM"
 * 必要ならマッピングを拡充してください
 */
function mysite_brand_from_url(string $url): string {
    $host = parse_url($url, PHP_URL_HOST) ?: '';
    $host = preg_replace('/^www\./i', '', $host);

    // カスタムマップ（必要に応じて追加）
    $map = [
        'doujin-assets.dmm.co.jp' => 'FANZA',
        'dmm.co.jp'               => 'DMM',
        'images-na.ssl-images-amazon.com' => 'Amazon',
    ];
    foreach ($map as $needle => $brand) {
        if (stripos($host, $needle) !== false) return $brand;
    }

    // ドメイン末尾2ラベルをブランド化（例: example.co.jp -> example）
    $labels = explode('.', $host);
    if (count($labels) >= 2) {
        $core = $labels[count($labels)-2];
        return strtoupper($core);
    }
    return '';
}