<?php

declare(strict_types=1);

namespace IOcornerstone\Framework\Services;

use IOcornerstone\Framework\GzCompression;
use IOcornerstone\Framework\Enum\CompressionMethod as Method;

/** 
 * @author Robert Strutts
 * @copyright Copyright (c) 2022, Robert Strutts.
 * @license MIT
 */

class CookieSessionsHandlerException extends \Exception {}

class CookieSessionHandler implements \SessionHandlerInterface {
    public static string $cookieDomain;
    public static string $cookieName = 'SES';
    public static string $cookiePath = '/';
    public static bool $cookieSecure = true;
    public static bool $cookieHTTPOnly = true;
    private $enc;
   
    public function __construct($enc, array $options) {
        if (isset($options['cookie_domain'])) {
            self::$cookieDomain = $options['cookie_domain'];
        } else {
            self::$cookieDomain = $_SERVER['SERVER_NAME'] ?? '';
        }
        if (isset($options['cookie_name'])) {
            self::$cookieName = $options['cookie_name'];
        }
        if (isset($options['cookie_path'])) {
            self::$cookiePath = $options['cookie_path'];
        }
        if (isset($options['cookie_secure'])) {
            self::$cookieSecure = $options['cookie_secure'];
        } else {
            /**
             * @todo Fix this...use_secure
             */
            $use_secure = true;
            if ($use_secure === false) {
                self::$cookieSecure = false;
            }
        }
        if (isset($options['cookie_HTTP_only'])) {
            self::$cookieHTTPOnly = $options['cookie_HTTP_only'];
        }
        if (isset($options['use_compression'])) {
            self::$use_compression = $options['use_compression'];
        }
        if (isset($options['method'])) {
            $method = $options['method'];
        } else {
            $method = Method::DEFLATE;
        }
        if (isset($options['level'])) {
            $level = $options['level'];    
        } else {
            $level = 4;
        }
        if (isset($options['enabled'])) {
            $enabled = $options['enabled'];
        } else {
            $enabled = true;
        }        
        
        $this->compression = new GzCompression($method, $level, $enabled);
        
        $this->enc = $enc;        
    }

    private function writeHelper($data): string {
        $gc = $this->compression->compress($data);
        if ($gc !== false) {
            $data = $gc; // data is now compressed
        }
        if ($this->enc === false) {
            return $data; // encryption is off
        }
        $e = $this->enc->encrypt($data);
        return ($e !== false) ? $e : $data; // and encrypted
    }
    
    private function readHelper($data): string {
        if ($data === null || $data === false) {
            return "";
        }
        if ($this->enc !== false) {
            $de = $this->enc->decrypt($data);
            if ($de!== false) {
                $data = $de; // data is now decrypted
            }
        }
        $gd = $this->compression->decompress($data);
        return ($gd !== false) ? $gd : $data;
    }    
    
    public function open($save_path, $session_name):bool {
        return true;
    }

    public function close(): bool {
        return true;
    }

    public function read($id): false|string {
        $data = isset($_COOKIE[self::$cookieName]) ? $_COOKIE[self::$cookieName] : null;
        return $this->readHelper($data) ?: "";
    }

    public function write($id, $data): bool {
        if (headers_sent($file, $line)) {
            throw new CookieSessionsHandlerException("Error headers were already sent by $file on line # $line ");
        }
        $data = $this->writeHelper($data);
        /*
         * Google Chrome - 4096 bytes confirming to RFC.
         * If the data is over 4000 bytes, throw an exception
         * as web browsers only support up to 4K of Cookie Data!
         */
        if (strlen($data) > 4000) {
            throw new cookie_sessions_handler_exception("Session data too big (over 4KB)");
        }
        $cookie_lifetime = (int) ini_get('session.cookie_lifetime');
        
        return setcookie(self::$cookieName, $data, $cookie_lifetime, self::$cookiePath, self::$cookieDomain, self::$cookieSecure, self::$cookieHTTPOnly);
    }

    public function destroy($id): bool {
        $expiration_time = time() - 3600;
        return setcookie(self::$cookieName, "", $expiration_time, self::$cookiePath, self::$cookieDomain, self::$cookieSecure, self::$cookieHTTPOnly);
    }

    public function gc($max_lifetime): int|false {
        return 0;
    }
}