<?php
namespace ProVM\NotariaRaby\Common\Service;

use Psr\Http\Message\ServerRequestInterface as Request;
use Carbon\Carbon;
use ProVM\Common\Service\Filemanager;

class Login {
  protected $cookie_name;
  protected $time_limit;
  protected $password;
  protected $filename;
  protected $manager;
  public function __construct(string $cookie_name, int $time_limit, string $base_url, string $encrypted_password, string $login_file, Filemanager $filemanager) {
    $this->cookie_name = $cookie_name;
    $this->base_url = $base_url;
    $this->time_limit = $time_limit;
    $this->password = $encrypted_password;
    $this->filename = $login_file;
    $this->manager = $filemanager;
  }

  protected $selector;
  protected $token;
  public function loadCookie() {
    if (isset($_COOKIE[$this->cookie_name])) {
  		list($s, $t) = \explode(':', $_COOKIE[$this->cookie_name]);
  		$this->selector = $s;
  		$this->token = $t;
  	}
  }
  public function saveCookie() {
  	$now = Carbon::now();
  	$exp = $now->addSeconds($this->time_limit);
    \setcookie($this->cookie_name, implode(':', [$this->selector, $this->token]), $exp->timestamp, $this->base_url);
  }
  public function removeCookie() {
    \setcookie($this->cookie_name, '', Carbon::now()->timestamp, '/');
  }
  protected function generateToken() {
    $this->selector = bin2hex(\random_bytes(12));
    $this->token = bin2hex(\random_bytes(20));
  }
  protected $data;
  public function getData() {
    if ($this->data === null) {
      $this->data = (object) [
        'ip' => 0,
        'token' => '',
        'time' => 0
      ];
      if ($this->manager->folder('data')->exists($this->filename)) {
        $this->data = $this->manager->folder('data')->load($this->filename);
        $this->data->time = Carbon::parse($this->data->time);
      }
    }
  }
  protected $ip;
  public function getIp(Request $request) {
    if ($this->ip === null) {
      $this->ip = $request->getHeader('host')[0];
    }
    return $this->ip;
  }

  protected $is_logged_in;
  public function checkAuth(Request $request): bool {
    if ($this->is_logged_in === null) {
      $this->loadCookie();
      if ($this->selector === null) {
        $this->is_logged_in = false;
        return false;
      }
      $this->getIp($request);
      $this->getData();

      if ($this->data->ip != $this->ip) {
        $this->is_logged_in = false;
        return false;
      }
      if ($this->data->token != implode(':', [$this->selector, $this->token])) {
        $this->is_logged_in = false;
        return false;
      }
      $now = Carbon::now();
      if ($this->data->time->copy()->addSeconds($this->time_limit)->diffInSeconds($now->copy()) < 0) {
        $this->is_logged_in = false;
      }
      $this->is_logged_in = true;
    }
    return $this->is_logged_in;
  }
  public function login(Request $request): bool {
    $post = $request->getParsedBody();
    if (!password_verify($post['clave'], $this->password)) {
      return false;
    }
    $this->generateToken();
    $this->getIp($request);
    $time = Carbon::now();
    $data = [
      'ip' => $this->ip,
      'token' => implode(':', [$this->selector, $this->token]),
      'time' => $time->format('Y-m-d H:i')
    ];
    $this->manager->folder('data')->save($this->filename, $data);
    $this->saveCookie();
    $this->is_logged_in = true;
    return true;
  }
  public function logout(): bool {
    $this->removeCookie();
    $data = [
      'ip' => 0,
      'token' => ':',
      'time' => 0
    ];
    $this->manager->folder('data')->save($this->filename, $data);
    $this->is_logged_in = false;
    return true;
  }
}