<?php
namespace ActiveTwist\SEO\Features;

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

use ActiveTwist\SEO\Settings\Options;

class RobotsController
{
    const OPTION_KEY_ROBOTS = 'robots_txt_content';

    public function init()
    {
        add_filter('robots_txt', [$this, 'filter_robots_txt'], 10, 2);
        add_action('admin_post_at_seo_save_robots', [$this, 'handle_save']);
        add_action('admin_post_at_seo_reset_robots', [$this, 'handle_reset']);
    }

    public function filter_robots_txt($output, $public)
    {
        // If site is not public, respect WP default which blocks everything
        if ('0' === get_option('blog_public')) {
            return $output;
        }

        $custom_content = Options::get(self::OPTION_KEY_ROBOTS);

        if (!empty($custom_content)) {
            return $custom_content;
        }

        // Return default appended to whatever WP generates (usually sitemaps etc)
        // Actually, WP robots_txt filter replaces content if we return a string and ignored the passed $output.
        // But usually plugins append to it or replace it.
        // PRD 2.2 says: "Provide a safe default template" and "Resulting robots.txt"
        // Let's stick to replacing it cleanly if we have content, or return default if empty?
        // Actually best practice is to handle the full output if we are an editor.

        return $output;
    }

    public function handle_save()
    {
        if (!current_user_can('manage_options')) {
            wp_die('Unauthorized');
        }

        check_admin_referer('at_seo_save_files', 'at_seo_files_nonce');

        $content = isset($_POST['at_seo_robots_content']) ? sanitize_textarea_field(wp_unslash($_POST['at_seo_robots_content'])) : '';

        // We need to save this into our main option array
        $options = Options::get_all();
        $options[self::OPTION_KEY_ROBOTS] = $content;
        update_option(Options::OPTION_NAME, $options);

        wp_safe_redirect(add_query_arg(['page' => 'active-twist-seo-files', 'tab' => 'robots', 'updated' => '1'], admin_url('admin.php')));
        exit;
    }

    public function handle_reset()
    {
        if (!current_user_can('manage_options')) {
            wp_die('Unauthorized');
        }

        check_admin_referer('at_seo_reset_robots', 'at_seo_min_nonce'); // Using different nonce name or same? Let's use specific action.

        $options = Options::get_all();
        unset($options[self::OPTION_KEY_ROBOTS]); // Remove key to revert to default
        update_option(Options::OPTION_NAME, $options);

        wp_safe_redirect(add_query_arg(['page' => 'active-twist-seo-files', 'tab' => 'robots', 'reset' => '1'], admin_url('admin.php')));
        exit;
    }

    public static function get_default_content()
    {
        $site_url = home_url();
        $sitemap_url = home_url('/sitemap.xml');

        return "User-agent: *\nDisallow: /wp-admin/\nAllow: /wp-admin/admin-ajax.php\n\nSitemap: {$sitemap_url}";
    }
}