<?php
/**
 * AEO Bob Lite - basic llms.txt generator (v1.5.85, reworked in v1.5.87)
 *
 * AEO Bob > llms.txt: "Generate llms.txt" writes /llms.txt at the site root (the folder WordPress's
 * home URL points to): the site name and description, then the key pages (home page first, then
 * pages in your menus, then the rest) and the latest posts, each with a one-line description
 * (llmstxt.org format). Only on a button click, by an administrator; no external calls.
 *
 * Left out: password-protected pages, anything set to noindex in Yoast, Rank Math, All in One SEO
 * (3 and 4) or SEOPress, shop/account/checkout/thank-you/login pages (from WooCommerce's and Easy
 * Digital Downloads' page settings, plus their usual slugs) - and whatever the
 * aeo_bob_lite_llms_exclude filter says.
 *
 * An llms.txt written by AEO Bob (Pro, or Lite) is AEO Bob's own and Generate replaces it. A file
 * from anything else is only replaced when the administrator ticks "Replace it". Every Generate
 * ends with a visible result: created / updated (with counts and size), not replaced, not
 * writable, or failed. llms-full.txt, engine prompt files and Notify AI Models are AEO Bob Pro.
 */

if (!defined('ABSPATH')) {
    exit;
}

class AEO_Bob_Lite_Llms {

    const OPTION    = 'aeo_bob_lite_llms';   // {hash, generated_at, pages, posts, bytes} of the file Lite last wrote
    const PAGE      = 'aeo-bob-lite-llms';
    const ACTION    = 'aeo_bob_lite_llms';
    const AJAX      = 'aeo_bob_lite_generate_llms'; // v1.5.88: Generate from the AEO BOB Score box
    const UPGRADE_URL = 'https://aeobob.com/?utm_source=lite&utm_medium=llms-alert#choose-your-plan';
    const MAX_ITEMS = 25;                    // per section
    const MARKER    = '<!-- Generated by AEO Bob Lite';

    /** Headers of the llms.txt files AEO Bob Pro writes (it is AEO Bob's own file). v1.5.88: any file that mentions AEO Bob counts too. */
    const PRO_SIGNATURES = '/^(?:# llms\.txt — Curated AI Discovery Index|# LLMs\.txt - AI Discovery File|# AEO BOB Discovery)|^# (?:Plugin: AEO Bob v|Generated by AEO BOB)/mi';

    /** Utility / transactional page slugs that never belong in llms.txt. */
    const UTILITY_SLUGS = '/^(?:cart|basket|checkout|my-account|account|my-orders|orders|order-received|order-confirmation|purchase-confirmation|purchase-history|transaction-failed|thank-you|thankyou|thanks|login|log-in|register|lost-password|password-reset|wishlist)(?:-\d+)?$/';

    private static $instance = null;
    private $counts = array('pages' => 0, 'posts' => 0);

    public static function get_instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }

    private function __construct() {
        // The menu item is added by AEO_Bob_Lite::add_admin_menu() with the other AEO Bob pages (v1.5.86).
        add_action('admin_post_' . self::ACTION, array($this, 'handle_post'));
        add_action('wp_ajax_' . self::AJAX, array($this, 'ajax_generate'));
        add_action('admin_enqueue_scripts', array($this, 'enqueue'));
    }

    /** v1.5.87: the Generate button's spinner (llms.txt page only). */
    public function enqueue($hook) {
        if (strpos((string) $hook, self::PAGE) === false) {
            return;
        }
        wp_enqueue_script('aeo-bob-lite-llms', AEO_BOB_LITE_URL . 'assets/js/llms.js', array(), aeo_bob_lite_asset_ver('assets/js/llms.js'), true);
        wp_localize_script('aeo-bob-lite-llms', 'aeoBobLiteLlms', array(
            'generating' => __('Generating llms.txt...', 'aeo-bob-lite'),
            'deleting'   => __('Deleting...', 'aeo-bob-lite'),
        ));
    }

    // ------------------------------------------------------------------ content

    /** The llms.txt text for this site right now. */
    public function build() {
        $lines = array();
        $lines[] = '# ' . $this->clean(get_bloginfo('name'));
        $description = $this->clean(get_bloginfo('description'));
        if ($description !== '') {
            $lines[] = '';
            $lines[] = '> ' . $description;
        }
        $pages = $this->items('page');
        if ($pages) {
            $lines[] = '';
            $lines[] = '## ' . __('Pages', 'aeo-bob-lite');
            $lines = array_merge($lines, $pages);
        }
        $posts = $this->items('post');
        if ($posts) {
            $lines[] = '';
            $lines[] = '## ' . __('Posts', 'aeo-bob-lite');
            $lines = array_merge($lines, $posts);
        }
        $this->counts = array('pages' => count($pages), 'posts' => count($posts));
        $lines[] = '';
        $lines[] = self::MARKER . ' ' . AEO_BOB_LITE_VERSION . ' -->';
        return implode("\n", $lines) . "\n";
    }

    /** Pages and posts listed by the last build(). */
    public function counts() {
        return $this->counts;
    }

    /** "- [Title](url): description" for the listed items of a type, in order. */
    private function items($type) {
        $args = array(
            'post_type'      => $type,
            'post_status'    => 'publish',
            'has_password'   => false,
            'posts_per_page' => $type === 'page' ? 200 : self::MAX_ITEMS * 2,
            'no_found_rows'  => true,
        );
        if ($type === 'page') {
            $args['orderby'] = array('menu_order' => 'ASC', 'title' => 'ASC');
        } else {
            $args['orderby'] = 'date';
            $args['order'] = 'DESC';
        }
        $posts = array();
        foreach (get_posts($args) as $post) {
            if (!$this->is_excluded($post)) {
                $posts[] = $post;
            }
        }
        if ($type === 'page') {
            $posts = $this->order_pages($posts);
        }
        $out = array();
        foreach (array_slice($posts, 0, self::MAX_ITEMS) as $post) {
            $title = str_replace(array('[', ']'), array('(', ')'), $this->clean(get_the_title($post)));
            if ($title === '') {
                continue;
            }
            $line = '- [' . $title . '](' . esc_url_raw(get_permalink($post)) . ')';
            $desc = $this->describe($post);
            if ($desc !== '') {
                $line .= ': ' . $desc;
            }
            $out[] = $line;
        }
        return $out;
    }

    /** Home page first, then pages in the site's menus (menu order), then the rest. */
    private function order_pages(array $pages) {
        $rank = array();
        $front = (int) get_option('page_on_front');
        if ($front) {
            $rank[$front] = 0;
        }
        $i = 1;
        if (function_exists('wp_get_nav_menus')) {
            foreach ((array) wp_get_nav_menus() as $menu) {
                foreach ((array) wp_get_nav_menu_items($menu) as $item) {
                    if (isset($item->object, $item->object_id) && $item->object === 'page' && !isset($rank[(int) $item->object_id])) {
                        $rank[(int) $item->object_id] = $i++;
                    }
                }
            }
        }
        $pos = array();
        foreach ($pages as $n => $p) {
            $pos[$p->ID] = $n;
        }
        usort($pages, function ($a, $b) use ($rank, $pos) {
            $ra = isset($rank[$a->ID]) ? $rank[$a->ID] : PHP_INT_MAX;
            $rb = isset($rank[$b->ID]) ? $rank[$b->ID] : PHP_INT_MAX;
            return $ra !== $rb ? ($ra < $rb ? -1 : 1) : $pos[$a->ID] - $pos[$b->ID];
        });
        return $pages;
    }

    /** Is this page/post left out of llms.txt? (filter: aeo_bob_lite_llms_exclude) */
    public function is_excluded($post) {
        $excluded = in_array((int) $post->ID, $this->system_page_ids(), true)
            || preg_match(self::UTILITY_SLUGS, (string) $post->post_name)
            || $this->is_noindex($post->ID);
        return (bool) apply_filters('aeo_bob_lite_llms_exclude', (bool) $excluded, $post);
    }

    /** Shop / checkout / account pages from WooCommerce's and Easy Digital Downloads' settings. */
    private function system_page_ids() {
        $ids = array();
        foreach (array('woocommerce_cart_page_id', 'woocommerce_checkout_page_id', 'woocommerce_myaccount_page_id', 'woocommerce_pay_page_id',
            'woocommerce_thanks_page_id', 'woocommerce_view_order_page_id', 'woocommerce_edit_address_page_id', 'woocommerce_lost_password_page_id',
            'woocommerce_change_password_page_id', 'woocommerce_logout_page_id') as $opt) {
            $ids[] = (int) get_option($opt, 0);
        }
        $edd = get_option('edd_settings', array());
        if (is_array($edd)) {
            foreach (array('purchase_page', 'success_page', 'failure_page', 'purchase_history_page', 'login_page', 'login_redirect_page') as $key) {
                $ids[] = isset($edd[$key]) ? (int) $edd[$key] : 0;
            }
        }
        return array_values(array_filter(array_map('intval', (array) apply_filters('aeo_bob_lite_llms_excluded_ids', array_values(array_filter($ids))))));
    }

    /** noindex set in Yoast, Rank Math, All in One SEO 3/4 or SEOPress. */
    private function is_noindex($post_id) {
        if ((string) get_post_meta($post_id, '_yoast_wpseo_meta-robots-noindex', true) === '1'
            || (string) get_post_meta($post_id, '_aioseop_noindex', true) === 'on'
            || (string) get_post_meta($post_id, '_seopress_robots_index', true) === 'yes') {
            return true;
        }
        $rank_math = get_post_meta($post_id, 'rank_math_robots', true);
        if (is_array($rank_math) && in_array('noindex', $rank_math, true)) {
            return true;
        }
        $aioseo = $this->aioseo_row($post_id);
        return $aioseo && !empty($aioseo['robots_noindex']) && empty($aioseo['robots_default']);
    }

    /** All in One SEO 4 keeps its per-post settings in its own table. */
    private function aioseo_row($post_id) {
        global $wpdb;
        static $has_table = null;
        if (!isset($wpdb) || !is_object($wpdb) || !method_exists($wpdb, 'get_row')) {
            return null;
        }
        $table = $wpdb->prefix . 'aioseo_posts';
        if ($has_table === null) {
            // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
            $has_table = ($wpdb->get_var($wpdb->prepare('SHOW TABLES LIKE %s', $table)) === $table);
        }
        if (!$has_table) {
            return null;
        }
        // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.InterpolatedNotPrepared
        $row = $wpdb->get_row($wpdb->prepare("SELECT description, robots_default, robots_noindex FROM {$table} WHERE post_id = %d", $post_id), ARRAY_A);
        return is_array($row) ? $row : null;
    }

    /** A one-line description: the SEO meta description (AIOSEO, Yoast, Rank Math), else a clean excerpt. */
    private function describe($post) {
        $aioseo = $this->aioseo_row($post->ID);
        $candidates = array($aioseo && isset($aioseo['description']) ? (string) $aioseo['description'] : '');
        foreach (array('_aioseo_description', '_yoast_wpseo_metadesc', '_rank_math_description', '_aeo_bob_meta_description') as $key) {
            $candidates[] = (string) get_post_meta($post->ID, $key, true);
        }
        foreach ($candidates as $value) {
            // unresolved SEO-plugin templates (%%title%%, #post_excerpt, %excerpt%) are not descriptions
            if (trim($value) !== '' && !preg_match('/%%|#[a-z]+_[a-z_]+|%[a-z_]+%/i', $value)) {
                return $this->shorten($this->clean($value));
            }
        }
        $text = $post->post_excerpt !== '' ? $post->post_excerpt : $post->post_content;
        $text = preg_replace('/<!--.*?-->/s', ' ', (string) $text);
        $text = preg_replace('/<(script|style|form|noscript)\b[^>]*>.*?<\/\1>/is', ' ', $text);   // never form fields or code
        $text = preg_replace('/<h[1-6]\b[^>]*>.*?<\/h[1-6]>/is', ' ', $text); // body text, not the page's own headings
        return $this->shorten($this->clean($text));
    }

    /** Plain text: shortcodes and tags removed, entities decoded ("&#8211;" -> "–"), one line. */
    public function clean($text) {
        $text = preg_replace('/\[\/?[a-zA-Z_][\w-]*(?:\s[^\]]*)?\]/', ' ', (string) $text); // shortcode tags, never run
        $text = preg_replace('/<br\s*\/?>|<\/(?:p|div|li|h[1-6])>/i', ' ', $text);
        $text = html_entity_decode(wp_strip_all_tags($text), ENT_QUOTES | ENT_HTML5, 'UTF-8');
        return trim(preg_replace('/[\s\x{00A0}]+/u', ' ', $text));
    }

    /** At most 160 characters, cut at a sentence end when one fits, else at a word. */
    private function shorten($text) {
        if (mb_strlen($text) <= 160) {
            return $text;
        }
        $cut = mb_substr($text, 0, 160);
        if (preg_match('/^(.{60,}[.!?])\s/u', $cut . ' ', $m)) {
            return trim($m[1]);
        }
        $cut = mb_substr($text, 0, 157);
        $space = mb_strrpos($cut, ' ');
        return rtrim($space > 80 ? mb_substr($cut, 0, $space) : $cut, " ,;:-–—") . '...';
    }

    // ------------------------------------------------------------------ file

    /** /llms.txt at the site root (filterable for unusual setups). */
    public function path() {
        if (!function_exists('get_home_path')) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        return (string) apply_filters('aeo_bob_lite_llms_path', trailingslashit(get_home_path()) . 'llms.txt');
    }

    public function url() {
        return home_url('/llms.txt');
    }

    /**
     * Who made the existing file: '' (none), lite (Lite wrote it - recorded hash, or its marker),
     * pro (AEO Bob Pro's headers) or other.
     */
    public function owner() {
        $path = $this->path();
        if (!file_exists($path)) {
            return '';
        }
        $saved = get_option(self::OPTION, array());
        $content = (string) @file_get_contents($path); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- local file
        if ((is_array($saved) && !empty($saved['hash']) && hash_equals((string) $saved['hash'], md5($content))) || strpos($content, self::MARKER) !== false) {
            return 'lite';
        }
        $text = preg_replace('/^\xEF\xBB\xBF/', '', $content); // a byte-order mark must not hide the first line
        return preg_match(self::PRO_SIGNATURES, $text) || preg_match('/\bAEO[\s_-]*Bob\b/i', $text) ? 'pro' : 'other';
    }

    /**
     * v1.5.88: the plugin that made another llms.txt, when it says so ("Generated by All in One SEO
     * v5.0.2.1" on billiardaimtrainer.com), else ''.
     */
    public function generator() {
        $path = $this->path();
        if (!file_exists($path)) {
            return '';
        }
        $head = (string) @file_get_contents($path, false, null, 0, 2000); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- local file
        foreach (array('All in One SEO', 'Yoast SEO', 'Rank Math', 'SEOPress', 'The SEO Framework', 'Website LLMs.txt') as $name) {
            if (stripos($head, $name) !== false) {
                return $name;
            }
        }
        return '';
    }

    /** v1.5.88: one-line state for the AEO BOB Score box: "Not created yet" / "Created by AEO Bob" / "Existing file found (All in One SEO)". */
    public function state_label($owner = null) {
        $owner = null === $owner ? $this->owner() : $owner;
        if ('' === $owner) {
            return __('Not created yet', 'aeo-bob-lite');
        }
        if ('other' !== $owner) {
            return __('Created by AEO Bob', 'aeo-bob-lite');
        }
        $by = $this->generator();
        /* translators: %s: plugin that made the existing llms.txt, e.g. "All in One SEO" */
        return '' !== $by ? sprintf(__('Existing file found (made by %s)', 'aeo-bob-lite'), $by) : __('Existing file found', 'aeo-bob-lite');
    }

    /** v1.5.88: "Last generated: <date time>" for AEO Bob's own file, else ''. */
    public function last_generated_text($status = null) {
        $status = null === $status ? $this->status() : $status;
        if (empty($status['generated_at'])) {
            return '';
        }
        $when = function_exists('wp_date') ? wp_date(get_option('date_format') . ' ' . get_option('time_format'), $status['generated_at']) : gmdate('Y-m-d H:i', $status['generated_at']);
        /* translators: %s: date and time */
        return sprintf(__('Last generated: %s', 'aeo-bob-lite'), $when);
    }

    /** @return array {exists, owner, ours (Lite's own), writable, generated_at, generated_by} */
    public function status() {
        $path = $this->path();
        $exists = file_exists($path);
        $owner = $this->owner();
        $saved = get_option(self::OPTION, array());
        $at = 0;
        $by = '';
        if ($owner === 'lite') {
            $at = is_array($saved) && !empty($saved['generated_at']) ? (int) $saved['generated_at'] : (int) @filemtime($path);
            $by = 'AEO Bob Lite';
        } elseif ($owner === 'pro') {
            $content = (string) @file_get_contents($path); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- local file
            $at = preg_match('/^# (?:Generated|Last updated):\s*(\S+(?: \S+)?)/mi', $content, $m) ? (int) strtotime($m[1]) : (int) @filemtime($path);
            $by = 'AEO Bob Pro';
        }
        return array(
            'exists'       => $exists,
            'owner'        => $owner,
            'ours'         => $owner === 'lite',
            'writable'     => $exists ? wp_is_writable($path) : wp_is_writable(dirname($path)),
            'generated_at' => $at,
            'generated_by' => $by,
        );
    }

    /** The WordPress filesystem, when it can write without asking for FTP credentials. */
    private function filesystem() {
        global $wp_filesystem;
        if (!function_exists('WP_Filesystem')) {
            require_once ABSPATH . 'wp-admin/includes/file.php';
        }
        if (!WP_Filesystem() || !$wp_filesystem) {
            return null;
        }
        return $wp_filesystem;
    }

    /**
     * Write /llms.txt. AEO Bob's own file (Lite or Pro) is replaced; another file only with $replace.
     *
     * @return array {code: created|updated|not_replaced|not_writable|failed, pages, posts, bytes, previous}
     */
    public function write($replace = false) {
        $status = $this->status();
        $result = array('code' => '', 'pages' => 0, 'posts' => 0, 'bytes' => 0, 'previous' => $status['owner']);
        if ($status['owner'] === 'other' && !$replace) {
            $result['code'] = 'not_replaced';
            return $result;
        }
        if (!$status['writable']) {
            $result['code'] = 'not_writable';
            return $result;
        }
        $fs = $this->filesystem();
        if (!$fs) {
            $result['code'] = 'not_writable';
            return $result;
        }
        $content = $this->build();
        if (!$fs->put_contents($this->path(), $content, defined('FS_CHMOD_FILE') ? FS_CHMOD_FILE : 0644)) {
            $result['code'] = 'failed';
            return $result;
        }
        $counts = $this->counts();
        update_option(self::OPTION, array('hash' => md5($content), 'generated_at' => time(), 'pages' => $counts['pages'], 'posts' => $counts['posts'], 'bytes' => strlen($content)), false);
        return array_merge($result, $counts, array('code' => $status['exists'] ? 'updated' : 'created', 'bytes' => strlen($content)));
    }

    /** Is /llms.txt exactly what Lite last wrote (not edited since)? */
    public function unedited() {
        $saved = get_option(self::OPTION, array());
        $path = $this->path();
        return is_array($saved) && !empty($saved['hash']) && file_exists($path) && hash_equals((string) $saved['hash'], (string) md5_file($path));
    }

    /** Delete /llms.txt - only the file Lite wrote, unedited (anything else is left alone). */
    public function delete() {
        if (!$this->unedited()) {
            return 'not_deleted';
        }
        $fs = $this->filesystem();
        if (!$fs || !$fs->delete($this->path())) {
            return 'failed';
        }
        delete_option(self::OPTION);
        return 'deleted';
    }

    // ------------------------------------------------------------------ admin

    /** admin-post.php?action=aeo_bob_lite_llms - Generate / Regenerate / Delete. Always ends with a result. */
    public function handle_post() {
        if (!current_user_can('manage_options')) {
            wp_die(esc_html__('You do not have permission to do this.', 'aeo-bob-lite'), 403);
        }
        check_admin_referer(self::ACTION);
        $op = isset($_POST['op']) ? sanitize_key(wp_unslash($_POST['op'])) : '';
        if ($op === 'delete') {
            $result = array('code' => $this->delete());
        } else {
            $result = $this->write(!empty($_POST['replace']));
        }
        // the result travels in a short-lived per-user note (and the code in the URL as a fallback),
        // so the page always shows what happened
        set_transient(self::result_key(), $result, 5 * MINUTE_IN_SECONDS);
        wp_safe_redirect(add_query_arg('aeo_llms', $result['code'], admin_url('admin.php?page=' . self::PAGE)));
        exit;
    }

    /**
     * v1.5.88: admin-ajax.php?action=aeo_bob_lite_generate_llms - Generate from the AEO BOB Score box
     * without leaving the editor. Another plugin's llms.txt is only replaced with replace=1: without
     * it the answer is {confirm: true} and the box asks "Replace the existing llms.txt? Yes / Cancel".
     */
    public function ajax_generate() {
        if (!check_ajax_referer(self::AJAX, 'nonce', false)) {
            wp_send_json_error(array('code' => 'nonce', 'message' => __('Your session has expired. Reload the page and try again.', 'aeo-bob-lite')), 403);
        }
        if (!current_user_can('manage_options')) {
            wp_send_json_error(array('code' => 'forbidden', 'message' => __('Only administrators can generate llms.txt.', 'aeo-bob-lite')), 403);
        }
        // v1.5.92: like Pro's Generate, also build this post's schema (Article + FAQPage), so the
        // AEO score's Schema markup factor counts it. Independent of the llms.txt result.
        $schema = '';
        $post_id = isset($_POST['post_id']) ? absint(wp_unslash($_POST['post_id'])) : 0;
        if ($post_id && current_user_can('edit_post', $post_id) && class_exists('AEO_Bob_Lite_Schema')) {
            $schema = AEO_Bob_Lite_Schema::get_instance()->generate($post_id);
        }
        $result = $this->write(!empty($_POST['replace']));
        $status = $this->status();
        $data = array(
            'code'          => $result['code'],
            'state'         => $this->state_label($status['owner']),
            'lastGenerated' => $this->last_generated_text($status),
            'viewUrl'       => $status['exists'] ? $this->url() : '',
            'schema'        => $schema, // v1.5.92
        );
        if (in_array($result['code'], array('created', 'updated'), true)) {
            $data['message'] = sprintf(
                /* translators: 1: number of pages, 2: number of posts */
                'created' === $result['code'] ? __('llms.txt created: %1$d pages, %2$d posts', 'aeo-bob-lite') : __('llms.txt updated: %1$d pages, %2$d posts', 'aeo-bob-lite'),
                (int) $result['pages'], (int) $result['posts']
            );
            wp_send_json_success($data);
        }
        if ('not_replaced' === $result['code']) {
            $by = $this->generator();
            $data['confirm'] = true;
            $data['message'] = '' !== $by
                /* translators: %s: plugin that made the existing llms.txt, e.g. "All in One SEO" */
                ? sprintf(__('Replace the existing llms.txt (made by %s)?', 'aeo-bob-lite'), $by)
                : __('Replace the existing llms.txt?', 'aeo-bob-lite');
            wp_send_json_error($data);
        }
        $notice = $this->notice_for($result);
        $data['message'] = $notice[1];
        wp_send_json_error($data);
    }

    /**
     * v1.5.88: "Notify AI Models" where AEO Bob Pro has it (Step 3, directly under the Generate
     * button). v1.5.89: always shown to administrators, full width like Generate. Locked in Lite:
     * the button only opens a short note with "Upgrade to Pro" - Lite never sends any notification.
     */
    public static function render_notify_locked() {
        ?>
        <div class="aeo-bob-llms-notify">
            <button type="button" class="button button-large aeo-bob-llms-notify-btn" aria-expanded="false">
                🔒 <?php esc_html_e('Notify AI Models (Pro)', 'aeo-bob-lite'); ?>
            </button>
            <div class="aeo-bob-llms-notify-note" style="display:none;">
                <p><?php esc_html_e('AEO Bob Pro notifies AI models and search engines that your llms.txt was updated, so they pick up changes faster.', 'aeo-bob-lite'); ?></p>
                <a href="<?php echo esc_url(self::UPGRADE_URL); ?>" target="_blank" rel="noopener noreferrer" class="button aeo-bob-upgrade-btn aeo-bob-upgrade-button"><?php esc_html_e('Upgrade to Pro', 'aeo-bob-lite'); ?></a>
            </div>
        </div>
        <?php
    }

    private static function result_key() {
        return 'aeo_bob_lite_llms_result_' . get_current_user_id();
    }

    /** "3.2 KB" */
    private function size($bytes) {
        return $bytes >= 1024 ? number_format_i18n($bytes / 1024, 1) . ' KB' : (int) $bytes . ' B';
    }

    /** [type, text, with_view_link] for a result. */
    public function notice_for(array $result) {
        $result = array_merge(array('pages' => 0, 'posts' => 0, 'bytes' => 0, 'previous' => ''), $result);
        $counts = sprintf(
            /* translators: 1: number of pages, 2: number of posts, 3: file size (e.g. "3.2 KB") */
            __('%1$d pages, %2$d posts, %3$s', 'aeo-bob-lite'),
            (int) $result['pages'], (int) $result['posts'], $this->size((int) $result['bytes'])
        );
        switch (isset($result['code']) ? $result['code'] : '') {
            case 'created':
                /* translators: %s: "14 pages, 10 posts, 3.2 KB" */
                return array('success', sprintf(__('llms.txt created: %s.', 'aeo-bob-lite'), $counts), true);
            case 'updated':
                $text = $result['previous'] === 'pro'
                    /* translators: %s: "14 pages, 10 posts, 3.2 KB" */
                    ? sprintf(__('llms.txt updated (it replaced the file AEO Bob Pro wrote): %s.', 'aeo-bob-lite'), $counts)
                    /* translators: %s: "14 pages, 10 posts, 3.2 KB" */
                    : sprintf(__('llms.txt updated: %s.', 'aeo-bob-lite'), $counts);
                return array('success', $text, true);
            case 'deleted':
                return array('success', __('llms.txt was deleted.', 'aeo-bob-lite'), false);
            case 'not_deleted':
                return array('warning', __('Not deleted: llms.txt was changed since AEO Bob Lite wrote it (or was not written by Lite), so it is left alone.', 'aeo-bob-lite'), true);
            case 'not_replaced':
                return array('warning', __('Not replaced: your site already has an llms.txt that was not created by AEO Bob. Tick "Replace it" to overwrite it.', 'aeo-bob-lite'), true);
            case 'not_writable':
                return array('error', __('llms.txt could not be written: WordPress cannot write to your site root (file permissions, or your host asks for FTP details). Copy the preview below into a file named llms.txt in the folder that holds wp-config.php, or ask your host to make that folder writable.', 'aeo-bob-lite'), false);
            default:
                return array('error', __('llms.txt could not be written or deleted (an unexpected error). Nothing was changed - please try again.', 'aeo-bob-lite'), false);
        }
    }

    public function render_page() {
        if (!current_user_can('manage_options')) {
            return;
        }
        // The result of the last Generate/Delete: the per-user note, else the code in the URL.
        $result = get_transient(self::result_key());
        if ($result !== false) {
            delete_transient(self::result_key());
        }
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- display-only result code from our own redirect
        $code = isset($_GET['aeo_llms']) ? sanitize_key(wp_unslash($_GET['aeo_llms'])) : '';
        if (!is_array($result) && $code !== '') {
            $saved = get_option(self::OPTION, array());
            $result = array_merge(is_array($saved) ? $saved : array(), array('code' => $code));
        }
        $notice = is_array($result) ? $this->notice_for($result) : null;
        $status = $this->status();
        // After a Generate, show the file that was actually written; before, what Generate will write.
        $from_file = $status['exists'] && $status['owner'] !== 'other';
        $preview = $from_file ? (string) @file_get_contents($this->path()) : $this->build(); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- local file
        $when = $status['generated_at'] ? (function_exists('wp_date') ? wp_date(get_option('date_format') . ' ' . get_option('time_format'), $status['generated_at']) : gmdate('Y-m-d H:i', $status['generated_at'])) : '';
        ?>
        <div class="wrap aeo-bob-lite-llms">
            <h1><?php esc_html_e('llms.txt', 'aeo-bob-lite'); ?></h1>
            <hr class="wp-header-end">
            <?php if ($notice) : ?>
                <div class="notice notice-<?php echo esc_attr($notice[0]); ?> aeo-bob-llms-result" role="status"><p>
                    <?php echo esc_html($notice[1]); ?>
                    <?php if ($notice[2] && file_exists($this->path())) : ?>
                        <a href="<?php echo esc_url($this->url()); ?>" target="_blank" rel="noopener noreferrer"><?php esc_html_e('View llms.txt', 'aeo-bob-lite'); ?></a>
                    <?php endif; ?>
                </p></div>
            <?php endif; ?>

            <p><?php esc_html_e('llms.txt is a short, public summary of your site for AI assistants: your site name and description, then your key pages and latest posts with a one-line description each. AEO Bob Lite writes it as a file at your site root when you click the button below. Shop, account and other utility pages, password-protected pages and noindex pages are left out.', 'aeo-bob-lite'); ?></p>

            <table class="widefat striped aeo-bob-llms-status" style="max-width: 760px;">
                <tbody>
                    <tr>
                        <th scope="row"><?php esc_html_e('File', 'aeo-bob-lite'); ?></th>
                        <td><code><?php echo esc_html($this->url()); ?></code>
                            <?php if ($status['exists']) : ?>
                                - <a href="<?php echo esc_url($this->url()); ?>" target="_blank" rel="noopener noreferrer"><?php esc_html_e('View', 'aeo-bob-lite'); ?></a>
                            <?php endif; ?>
                        </td>
                    </tr>
                    <tr>
                        <th scope="row"><?php esc_html_e('Status', 'aeo-bob-lite'); ?></th>
                        <td class="aeo-bob-llms-state">
                            <?php
                            if (!$status['exists']) {
                                esc_html_e('Not created yet.', 'aeo-bob-lite');
                            } elseif ($status['owner'] === 'other') {
                                esc_html_e('An llms.txt exists that was not created by AEO Bob (or was edited by hand). It is not changed unless you choose to replace it.', 'aeo-bob-lite');
                                if ('' !== $this->generator()) {
                                    /* translators: %s: plugin that made the existing llms.txt, e.g. "All in One SEO" */
                                    echo ' ' . esc_html(sprintf(__('It was made by %s - if you replace it, turn off that plugin\'s llms.txt option so it does not write its own file again.', 'aeo-bob-lite'), $this->generator()));
                                }
                            } else {
                                esc_html_e('Created by AEO Bob. Generate updates it.', 'aeo-bob-lite');
                            }
                            ?>
                            <?php if ($when !== '') : ?>
                                <br><span class="aeo-bob-llms-last">
                                    <?php
                                    /* translators: 1: date and time, 2: "AEO Bob Lite" or "AEO Bob Pro" */
                                    echo esc_html(sprintf(__('Last generated: %1$s by %2$s', 'aeo-bob-lite'), $when, $status['generated_by']));
                                    ?>
                                </span>
                            <?php endif; ?>
                        </td>
                    </tr>
                    <?php if (!$status['writable']) : ?>
                        <tr>
                            <th scope="row"><?php esc_html_e('Write access', 'aeo-bob-lite'); ?></th>
                            <td class="aeo-bob-llms-not-writable"><strong><?php esc_html_e('WordPress cannot write to your site root, so the file cannot be created from here. Copy the preview into a file named llms.txt in the folder that holds wp-config.php.', 'aeo-bob-lite'); ?></strong></td>
                        </tr>
                    <?php endif; ?>
                </tbody>
            </table>

            <div class="aeo-bob-llms-actions">
            <form method="post" action="<?php echo esc_url(admin_url('admin-post.php')); ?>" class="aeo-bob-llms-form" style="margin-top: 16px;">
                <?php wp_nonce_field(self::ACTION); ?>
                <input type="hidden" name="action" value="<?php echo esc_attr(self::ACTION); ?>">
                <input type="hidden" name="op" value="generate">
                <?php if ($status['owner'] === 'other') : ?>
                    <p><label><input type="checkbox" name="replace" value="1"> <?php esc_html_e('Replace it (the existing llms.txt will be overwritten)', 'aeo-bob-lite'); ?></label></p>
                <?php endif; ?>
                <button type="submit" class="button button-primary button-large" id="aeo-bob-llms-generate"<?php disabled(!$status['writable']); ?>>
                    <?php echo esc_html($status['exists'] && $status['owner'] !== 'other' ? __('Regenerate llms.txt', 'aeo-bob-lite') : __('Generate llms.txt', 'aeo-bob-lite')); ?>
                </button>
                <span class="spinner aeo-bob-llms-spinner" style="float: none;"></span>
            </form>
            <?php self::render_notify_locked(); ?>
            </div>

            <?php if ($this->unedited()) : ?>
                <form method="post" action="<?php echo esc_url(admin_url('admin-post.php')); ?>" class="aeo-bob-llms-form" style="margin-top: 8px;">
                    <?php wp_nonce_field(self::ACTION); ?>
                    <input type="hidden" name="action" value="<?php echo esc_attr(self::ACTION); ?>">
                    <input type="hidden" name="op" value="delete">
                    <button type="submit" class="button" id="aeo-bob-llms-delete"><?php esc_html_e('Delete llms.txt', 'aeo-bob-lite'); ?></button>
                    <span class="spinner aeo-bob-llms-spinner" style="float: none;"></span>
                </form>
            <?php endif; ?>

            <h2><?php echo esc_html($from_file ? __('Current llms.txt', 'aeo-bob-lite') : __('Preview', 'aeo-bob-lite')); ?></h2>
            <?php if (!$from_file) : ?>
                <p class="description"><?php esc_html_e('This is what Generate will write.', 'aeo-bob-lite'); ?></p>
            <?php endif; ?>
            <textarea class="large-text code" rows="18" readonly id="aeo-bob-llms-preview"><?php echo esc_textarea($preview); ?></textarea>

            <p class="description">
                <?php esc_html_e('AEO Bob Pro adds llms-full.txt, engine prompt files and Notify AI Models, and serves llms.txt itself - if you upgrade, delete this file first so Pro\'s version is used.', 'aeo-bob-lite'); ?>
            </p>
        </div>
        <?php
    }
}

AEO_Bob_Lite_Llms::get_instance();