<?php
//$fs = new furatalogSessions();

//$fs->setSessionData("nsfw", true);
//$fs->getSessionData("nsfw");

class furatalogSessions {
    public $cookieKey = "";
    public $dataObj;
    private mysqli $db;
    private $cookie_duration = 30 * 24 * 60 * 60;

    public function __construct() {
        $this->dataObj = (object) array();
        $this->connectDb();
        $this->getCookieKey();
        $this->getData();
    }

    public function setSessionData($varName, $content) {
        $this->dataObj->{$varName} = $content;
        $this->saveToDb();
        $this->saveCookie();
    }

    public function getSessionData($varName) {
        try {
            return $this->dataObj->{$varName};
        } catch (Exception $e) {
            return null;
        }
    }

    public function unsetSessionData($varName) {
        unset($this->dataObj->{$varName});
    }

    public function issetSessionData($varName) {
        return isset($this->dataObj->{$varName});
    }

    public function destroy() {
        $this->deleteData($this->cookieKey);
        $this->deleteCookie();
    }

    private function saveToDb() {
        $jsonDataToSave = json_encode($this->dataObj, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP | JSON_UNESCAPED_UNICODE);
        
        $tmpresult = $this->db->query("SELECT cookieKey FROM `sessions` WHERE cookieKey=\"" . $this->cookieKey . "\"");
        if (!($tmpresult->num_rows > 0)) {
            $this->db->query("INSERT INTO `sessions`(`cookieKey`, `lastused`, `data`) VALUES ('" . $this->cookieKey . "', now(),'" . $jsonDataToSave . "')");
        } else {
            $this->db->query("UPDATE `sessions` SET lastused=now(), data='" . $jsonDataToSave . "' WHERE cookieKey=\"" . $this->cookieKey . "\";");
        }
    }

    private function saveCookie() {
        setcookie("_cookieKey", $this->cookieKey, [
            'expires' => time() + $this->cookie_duration,
            'path' => '/',
            'domain' => 'furatalog.xyz',
            'secure' => true,
            'httponly' => true,
            'samesite' => 'Lax'
        ]);
    }

    private function connectDb() {
        $this->db = new mysqli("localhost", "furatalog_admin_usr", "NR6tLk7c56bPT5[]", "furatalog");
    }

    private function getCookieKey() {
        $this->cookieKey = isset($_COOKIE["_cookieKey"]) ? $_COOKIE["_cookieKey"] : "";

        if ($this->cookieKey == "") {
            $this->cookieKey = $this->generateKey();
        }
    }

    private function getData() {
        $tmpresult = $this->db->query("SELECT id, cookieKey, UNIX_TIMESTAMP(lastused) as lastused, data FROM sessions WHERE cookieKey=\"" . $this->cookieKey . "\"");
        if ($tmpresult->num_rows > 0) {
            $fetchedData = $tmpresult->fetch_assoc();

            if ($fetchedData["lastused"] < strtotime('-30 days')) {
                $this->deleteData($fetchedData["cookieKey"]);
                $this->deleteCookie();
                $this->getCookieKey();
            } else {
                $this->dataObj = json_decode($fetchedData["data"]);
            }
        }
    }

    private function deleteCookie() {
        setcookie("_cookieKey", "", [
            'expires' => time()-3600,
            'path' => '/',
            'domain' => 'furatalog.xyz',
            'secure' => true,
            'httponly' => true,
            'samesite' => 'Lax'
        ]);
    }

    private function deleteData($cookieKey) {
        if ($cookieKey != "" && $cookieKey != null) {
            $tmpresult = $this->db->query("DELETE FROM sessions WHERE cookieKey=\"" . $cookieKey . "\"");
        }
    }

    private function generateKey() {
        $isNotInDB = false;

        do {
            $length = 20;
            $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
            $charactersLength = strlen($characters);
            $randomString = '';

            for ($i = 0; $i < $length; $i++) {
                $randomString .= $characters[random_int(0, $charactersLength - 1)];
            }

            $tmpresult = $this->db->query("SELECT cookieKey FROM `sessions` WHERE cookieKey=\"" . $randomString . "\"");
            if (!($tmpresult->num_rows > 0)) {
                $isNotInDB = true;
            }
        } while (!$isNotInDB);

        return $randomString;
    }
}