<?php

namespace Code\Lib;

use App;
use Code\Extend\Hook;
use URLify;

class System
{

    public static function get_platform_name()
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && array_key_exists('platform_name', App::$config['system'])) {
            return App::$config['system']['platform_name'];
        }
        return REPOSITORY_ID;
    }

    public static function get_site_name(): string
    {
        if (is_array(App::$sys_channel) && isset(App::$sys_channel['channel_name'])) {
            return App::$sys_channel['channel_name'];
        }
        return '';
    }

    public static function get_project_name()
    {
        $project = EMPTY_STR;
        $name = self::get_site_name();
        if ($name) {
            $words = explode(' ', $name);
            // restrict result to characters allowed by the nodeinfo specification
            $project = preg_replace('/[^a-z0-9-]/', '-', strtolower(URLify::transliterate($words[0])));
        }
        if (!$project) {
            $project = self::get_platform_name();
        }
        return $project;
    }

    
    public static function get_banner()
    {

        if (is_array(App::$config) && is_array(App::$config['system']) && array_key_exists('banner', App::$config['system']) && App::$config['system']['banner']) {
            return App::$config['system']['banner'];
        }
        return self::get_site_name();
    }

    public static function get_project_icon()
    {
        if (isset(App::$sys_channel['xchan_photo_l'])) {
            return App::$sys_channel['xchan_photo_l'];
        }
        if (is_array(App::$config) && is_array(App::$config['system']) && array_key_exists('icon', App::$config['system'])) {
            return App::$config['system']['icon'];
        }
        return z_root() . '/images/' . REPOSITORY_ID . '-64.png';
    }

    public static function get_project_favicon()
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && array_key_exists('favicon', App::$config['system'])) {
            return App::$config['system']['favicon'];
        }
        return z_root() . '/images/' . REPOSITORY_ID . '.ico';
    }


    public static function get_project_version()
    {
        if (array_path_exists('system/hide_version', App::$config) && intval(App::$config['system']['hide_version'])) {
            return '';
        }
        if (is_array(App::$config) && is_array(App::$config['system']) && array_key_exists('std_version', App::$config['system'])) {
            return App::$config['system']['std_version'];
        }

        return self::get_std_version();
    }

    public static function get_update_version(): int|string
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && App::$config['system']['hide_version']) {
            return EMPTY_STR;
        }
        return DB_UPDATE_VERSION;
    }

    public static function get_notify_icon()
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && App::$config['system']['email_notify_icon_url']) {
            return App::$config['system']['email_notify_icon_url'];
        }
        return self::get_project_icon();
    }

    public static function get_site_icon()
    {
        return self::get_project_icon();
    }

    public static function get_site_favicon()
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && App::$config['system']['site_favicon_url']) {
            return App::$config['system']['site_favicon_url'];
        }
        return self::get_project_favicon();
    }

    public static function get_project_srclink()
    {
        if (is_array(App::$config) && is_array(App::$config['system']) && App::$config['system']['project_srclink']) {
            return App::$config['system']['project_srclink'];
        }

        return 'https://codeberg.org/streams/' . REPOSITORY_ID;

    }

    public static function get_zot_revision()
    {
        $x = [ 'revision' => NOMAD_PROTOCOL_VERSION ];
        Hook::call('zot_revision', $x);
        return $x['revision'];
    }

    public static function get_std_version(): string
    {
        if (defined('STD_VERSION')) {
            return STD_VERSION;
        }
        return '0.0.0';
    }


    public static function getVapidKey()
    {
        $private_key = openssl_pkey_new([
            'private_key_type' => OPENSSL_KEYTYPE_EC,
            'curve_name' => 'prime256v1',
        ]);

        $details = openssl_pkey_get_details($private_key);
        $private_key_raw = $details['ec']['d'];
        $public_key_raw = $details['ec']['x'] . $details['ec']['y'];
        $auth_token = base64_encode(openssl_random_pseudo_bytes(16));

        $vapid = [
            'private_key' => rtrim(strtr(base64_encode($private_key_raw), '+/', '-_'), '='),
            'public_key' => rtrim(strtr(base64_encode($public_key_raw), '+/', '-_'), '='),
            'auth_token' => $auth_token,
        ];

        return json_encode($vapid);
    }

    public static function getApplicationServerKey($vapid)
    {
        $publicKey = $vapid['public_key'];
        $public_key_bytes = base64_decode($publicKey);

        // Check that the public key has the correct format
        if (strlen($public_key_bytes) != 65 || ord($public_key_bytes[0]) != 4) {
            // The public key has an incorrect format
            // Handle the error here
        }

        // Extract the x and y coordinates of the point
        $x = substr($public_key_bytes, 1, 32);
        $y = substr($public_key_bytes, 33, 32);

        // Pack the bytes of the public key in the correct order
        $application_server_key = "\x04" . $x . $y;
        return base64_encode($application_server_key);
    }
    
}