<?php
namespace Aiutoma\Modules\Markdown\Traits;
if ( ! defined( 'ABSPATH' ) ) exit;
trait Controller {
    public function inject_markdown_alternate_link() {
        if (get_query_var('aiutoma_md')) return;

        printf(
            '<link rel="alternate" type="text/markdown" title="%s" href="%s" />' . "\n",
            /* translators: %s: site name */
            esc_attr(sprintf(__('%s Markdown Feed', 'aiutoma'), get_bloginfo('name'))),
            esc_url(get_feed_link('markdown'))
        );

        if (!is_singular()) return;
        
        $post = get_queried_object();
        if (!$post instanceof \WP_Post || ($post->post_status !== 'publish' && !($post->post_type === 'attachment' && $post->post_status === 'inherit')) || post_password_required($post)) return;

        $allowed_cpts = get_option('aiutoma_markdown_cpts', false);
        if ($allowed_cpts === false) {
            $allowed_cpts = array_values(array_diff(array_keys(get_post_types(['public' => true])), ['attachment']));
        }
        if (!in_array($post->post_type, $allowed_cpts)) return;

        $canonical = get_permalink($post);
        if (!$canonical) return;
        
        $md_url = rtrim($canonical, '/') . '.md';
        $query_url = add_query_arg('output_format', 'markdown', $canonical);
        printf('<link rel="alternate" type="text/markdown" title="%s" href="%s" />' . "\n", esc_attr__('Markdown version', 'aiutoma'), esc_url($md_url));
        printf('<link rel="alternate" type="text/markdown" href="%s" />' . "\n", esc_url($query_url));
    }

    public function handle_accept_markdown_header() {
        if (get_query_var('aiutoma_md')) return;

        $accept = isset($_SERVER['HTTP_ACCEPT']) ? sanitize_text_field(wp_unslash($_SERVER['HTTP_ACCEPT'])) : '';
        if (strpos($accept, 'text/markdown') !== false) {
            if (is_singular()) {
                $post = get_queried_object();
                if ($post instanceof \WP_Post && ($post->post_status === 'publish' || ($post->post_type === 'attachment' && $post->post_status === 'inherit'))) {
                    $allowed_cpts = get_option('aiutoma_markdown_cpts', false);
                    if ($allowed_cpts === false) {
                        $allowed_cpts = array_values(array_diff(array_keys(get_post_types(['public' => true])), ['attachment']));
                    }
                    if (!in_array($post->post_type, $allowed_cpts)) return;

                    $canonical = get_permalink($post);
                    if ($canonical) {
                        $md_url = rtrim($canonical, '/') . '.md';
                        header('Vary: Accept');
                        wp_safe_redirect($md_url, 303);
                        exit;
                    }
                }
            }
        }
    }

    public function serve_markdown_content() {
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended
        $is_query_format = isset($_GET['output_format']) && 'markdown' === sanitize_key(wp_unslash((string)$_GET['output_format']));
        $is_md_var = (bool) get_query_var('aiutoma_md');

        if (!$is_md_var && !$is_query_format) return;
        if ($is_query_format && !is_singular() && !is_front_page()) return;
        
        // Prevent loopback
        if (isset($_SERVER['HTTP_X_WAI_RENDER'])) {
            status_header(404);
            exit;
        }

        $post = get_queried_object();
        if (!$post instanceof \WP_Post) {
            if (is_front_page()) {
                $page_on_front = get_option('page_on_front');
                if ($page_on_front) {
                    $post = get_post((int)$page_on_front);
                }
            }
        }

        if (!$post instanceof \WP_Post || ($post->post_status !== 'publish' && !($post->post_type === 'attachment' && $post->post_status === 'inherit'))) {
            status_header(404);
            exit;
        }

        $allowed_cpts = get_option('aiutoma_markdown_cpts', false);
        if ($allowed_cpts === false) {
            $allowed_cpts = array_values(array_diff(array_keys(get_post_types(['public' => true])), ['attachment']));
        }
        if (!in_array($post->post_type, $allowed_cpts)) {
            status_header(404);
            exit;
        }
        
        if (post_password_required($post)) {
            status_header(403);
            header('Content-Type: text/plain; charset=UTF-8');
            echo esc_html__('Content is password protected.', 'aiutoma');
            exit;
        }
        
        // Detect AI Bots
        $this->detect_and_log_ai_bot($post);

        $canonical = get_permalink($post);
        $markdown = $this->generate_post_markdown($post, $canonical);

        status_header(200);
        header('Content-Type: text/markdown; charset=' . get_bloginfo('charset'));
        header('Vary: Accept');
        header('X-Robots-Tag: noindex');
        header('Link: <' . $canonical . '>; rel="canonical"');
        header('X-Content-Type-Options: nosniff');
        header('X-Markdown-Tokens: ' . (int)(strlen($markdown) / 4));
        
        echo wp_kses_post($markdown);
        exit;
    }

    /**
     * Filters the content type reported for the markdown feed.
     */
    public function filter_markdown_feed_content_type($content_type, $type) {
        if ('markdown' === $type) {
            return 'text/markdown';
        }
        return $content_type;
    }

    /**
     * Renders the current feed query as a clean Markdown document.
     */
    public function render_markdown_feed() {
        if (!headers_sent()) {
            status_header(200);
            header('Content-Type: text/markdown; charset=' . get_bloginfo('charset'));
            header('X-Robots-Tag: noindex');
        }

        $use_excerpt = (bool) get_option('rss_use_excerpt');
        $site_name = wp_specialchars_decode(get_bloginfo('name'), ENT_QUOTES);
        $site_desc = wp_specialchars_decode(get_bloginfo('description'), ENT_QUOTES);

        $blocks = [
            '# ' . $site_name,
        ];
        if (!empty($site_desc)) {
            $blocks[] = $site_desc;
        }
        /* translators: %s: site home url */
        $blocks[] = '- ' . sprintf(__('Site: %s', 'aiutoma'), home_url('/'));

        while (have_posts()) {
            the_post();
            $post = get_post();
            if (!$post instanceof \WP_Post) {
                continue;
            }

            $permalink = (string) get_permalink($post);
            if ($use_excerpt) {
                $content = trim(wp_strip_all_tags((string) get_the_excerpt($post), true));
            } else {
                // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound
                $content_html = (string) apply_filters('the_content', get_the_content(null, false, $post));
                $content = trim($this->extract_markdown_from_html($content_html));
            }

            $meta_lines = [
                /* translators: %s: post permalink URL */
                '- ' . sprintf(__('Link: %s', 'aiutoma'), esc_url($permalink)),
                /* translators: %s: post publish date */
                '- ' . sprintf(__('Published: %s', 'aiutoma'), (string) get_the_date('c', $post)),
                /* translators: %s: post author display name */
                '- ' . sprintf(__('Author: %s', 'aiutoma'), (string) get_the_author_meta('display_name', (int) $post->post_author)),
            ];

            $item_sections = [
                'title'   => '## ' . wp_specialchars_decode((string) get_the_title($post), ENT_QUOTES),
                'meta'    => implode("\n", $meta_lines),
                'content' => $content,
            ];

            $item_sections = apply_filters('aiutoma_markdown_feed_item_sections', $item_sections, $post);
            $item_text = implode("\n\n", array_filter(array_map('trim', $item_sections)));
            if (!empty($item_text)) {
                $blocks[] = $item_text;
            }
        }
        wp_reset_postdata();

        $output = implode("\n\n", array_filter($blocks)) . "\n";

        echo wp_kses_post($output);
        exit;
    }

}