/**
 * AJAX: SEO COMPLETO (Contenido + Rank Math + Schema + Imágenes)
 * Enfoque robusto:
 * - Gemini devuelve JSON SIMPLE (no JSON-LD completo)
 * - PHP construye JSON-LD final
 */
add_action( 'wp_ajax_nv_gemini_generate_full_seo', function() {

    // Base: permisos + nonce + request disponible + rate-limit
    $post    = nv_gemini_check_ajax_base( 'nv_gemini_generate_save' );
    $post_id = $post->ID;

    $prompt = isset($_POST['prompt']) ? sanitize_textarea_field( wp_unslash($_POST['prompt']) ) : '';
    if ( empty( $prompt ) ) {
        wp_send_json_error([ 'message' => 'Prompt vacío.' ]);
    }

    // Contexto (capado para no enviar megas)
    $existing_title = get_post_meta( $post_id, 'rank_math_title', true );
    $page_title     = $existing_title ?: get_the_title( $post_id );

    $existing_content = wp_strip_all_tags( $post->post_content );
    if ( function_exists('mb_substr') ) {
        $existing_content = mb_substr( $existing_content, 0, 2000 );
    } else {
        $existing_content = substr( $existing_content, 0, 2000 );
    }

    /**
     * Importante:
     * - gemini-pro NO soporta JSON mode, así que NO intentamos response_mime_type JSON. [3](https://github.com/WordPress/health-check/blob/trunk/mu-plugin/health-check-troubleshooting-mode.php)
     * - Pedimos JSON SIMPLE para reducir respuestas vacías. [1](https://cvefeed.io/vuln/detail/CVE-2022-47161)
     */
    $instruction = "Eres un asistente SEO experto para WordPress.
Devuelve SOLO un JSON válido (sin texto extra). NO devuelvas JSON-LD completo.
Devuelve estas claves:

- title: título SEO (máx 60 caracteres)
- description: meta descripción (máx 160 caracteres)
- focus_keyword: keyword principal (frase corta)
- extra_keywords: array de 10 keywords adicionales (strings)
- content: HTML simple (sin scripts, sin iframes)
- schema_simple: objeto JSON simple (NO JSON-LD) con:
    - headline
    - description (máx 160)
    - author_name
    - date_published (YYYY-MM-DD)

TÍTULO ACTUAL:
{$page_title}

CONTENIDO ACTUAL (si existe):
{$existing_content}

PROMPT:
{$prompt}";

    // Con caché por prompt si existe helper
    if ( function_exists('nv_gemini_cached_request') ) {
        $raw = nv_gemini_cached_request( $instruction, 12 );
    } else {
        $raw = nv_gemini_pro_request( $instruction );
    }

    if ( empty( $raw ) ) {
        // generateContent puede devolver respuesta vacía sin error HTTP en algunos casos. [1](https://cvefeed.io/vuln/detail/CVE-2022-47161)
        wp_send_json_error([ 'message' => 'No devuelve contenido (API Key, timeout o bloqueo).' ]);
    }

    // Extraer JSON robustamente
    if ( function_exists('nv_extract_json_object') ) {
        $clean = nv_extract_json_object( $raw );
    } else {
        // fallback simple
        $raw2  = preg_replace('/^```(?:json)?/i', '', trim($raw));
        $raw2  = preg_replace('/```$/', '', trim($raw2));
        $start = strpos($raw2, '{');
        $end   = strrpos($raw2, '}');
        $clean = ($start !== false && $end !== false && $end > $start) ? substr($raw2, $start, $end - $start + 1) : '';
    }

    if ( empty($clean) ) {
        error_log('[NV Gemini] SEO completo: no se pudo extraer JSON. Raw: ' . substr($raw,0,500));
        wp_send_json_error([ 'message' => 'Respuesta sin JSON utilizable.' ]);
    }

    $json = json_decode( $clean, true );
    if ( ! is_array( $json ) ) {
        error_log('[NV Gemini] SEO completo: JSON inválido. Clean: ' . substr($clean,0,500));
        wp_send_json_error([ 'message' => 'La respuesta de Gemini no es JSON válido.' ]);
    }

    // -------------------------
    // Normalizar campos
    // -------------------------
    $title = sanitize_text_field( $json['title'] ?? '' );
    $desc  = sanitize_text_field( $json['description'] ?? '' );
    $kw    = sanitize_text_field( $json['focus_keyword'] ?? '' );

    if ( function_exists('mb_substr') ) {
        if ( $title ) $title = mb_substr( $title, 0, 60 );
        if ( $desc )  $desc  = mb_substr( $desc,  0, 160 );
    } else {
        if ( $title ) $title = substr( $title, 0, 60 );
        if ( $desc )  $desc  = substr( $desc,  0, 160 );
    }

    $extra_keywords = ( isset($json['extra_keywords']) && is_array($json['extra_keywords']) )
        ? array_values(array_filter(array_map('sanitize_text_field', $json['extra_keywords'] )))
        : [];

    // contenido HTML permitido
    $content_html = wp_kses_post( $json['content'] ?? '' );

    // schema_simple
    $schema_simple = ( isset($json['schema_simple']) && is_array($json['schema_simple']) ) ? $json['schema_simple'] : [];

    // -------------------------
    // 1) Guardar contenido en post_content
    // -------------------------
    if ( ! empty( $content_html ) ) {
        wp_update_post([
            'ID'           => $post_id,
            'post_content' => $content_html,
        ]);
    }

    // -------------------------
    // 2) Guardar metas Rank Math (keys oficiales)
    // -------------------------
    if ( $title !== '' ) update_post_meta( $post_id, 'rank_math_title', $title );           // [2](https://onedrive.live.com/?id=fb75e519-2aea-4490-8fea-9dcc9c3edeb9&cid=f68e591688629750&web=1)
    if ( $desc  !== '' ) update_post_meta( $post_id, 'rank_math_description', $desc );     // [2](https://onedrive.live.com/?id=fb75e519-2aea-4490-8fea-9dcc9c3edeb9&cid=f68e591688629750&web=1)
    if ( $kw    !== '' ) update_post_meta( $post_id, 'rank_math_focus_keyword', $kw );     // uso habitual en automatizaciones [4](https://woocommerce.com/document/troubleshooting-using-health-check/)

    // -------------------------
    // 3) Guardar keywords extra (meta propia)
    // -------------------------
    if ( ! empty( $extra_keywords ) ) {
        update_post_meta( $post_id, 'nv_gemini_extra_keywords', $extra_keywords );
    }

    // -------------------------
    // 4) Construir JSON-LD Article en PHP (estable)
    // -------------------------
    $headline = sanitize_text_field( $schema_simple['headline'] ?? ($title ?: $page_title) );
    $sd_desc  = sanitize_text_field( $schema_simple['description'] ?? $desc );
    $author   = sanitize_text_field( $schema_simple['author_name'] ?? 'Redacción' );
    $date_pub = sanitize_text_field( $schema_simple['date_published'] ?? date('Y-m-d') );

    if ( function_exists('mb_substr') ) {
        $sd_desc = mb_substr( $sd_desc, 0, 160 );
    } else {
        $sd_desc = substr( $sd_desc, 0, 160 );
    }

    if ( ! preg_match('/^\d{4}-\d{2}-\d{2}$/', $date_pub ) ) {
        $date_pub = date('Y-m-d');
    }

    $schema_ld = [
        '@context' => 'https://schema.org',
        '@type'    => 'Article',
        'headline' => $headline,
        'description' => $sd_desc,
        'author' => [
            '@type' => 'Person',
            'name'  => $author,
        ],
        'datePublished' => $date_pub,
        'inLanguage' => 'es-ES',
        'mainEntityOfPage' => get_permalink( $post_id ),
    ];

    if ( function_exists('nv_gemini_save_schema_raw') ) {
        nv_gemini_save_schema_raw( $post_id, $schema_ld );
    } else {
        update_post_meta( $post_id, 'nv_gemini_schema_raw', wp_json_encode( $schema_ld ) );
    }

    // -------------------------
    // 5) Optimizar imágenes (ALT/caption/desc solo si faltan)
    // -------------------------
    if ( function_exists('nv_gemini_optimize_images_for_post') ) {
        $seo_title_for_images = $title ?: $page_title;
        $html_for_images      = $content_html ?: $post->post_content;
        nv_gemini_optimize_images_for_post( $post_id, $seo_title_for_images, $html_for_images );
    }

    wp_send_json_success([
        'message' => 'SEO completo guardado: contenido + Rank Math (title/description/keyword) + schema + optimización de imágenes.'
    ]);
});