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<?php

class Auth
{

    public function __lang($str)
    {
        return $str;
    }

    public function bdd()
    {
        $pdo = new PDO('mysql:dbname=api;host=127.0.0.1', 'root', '');
        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
        return $pdo;
    }

    public function isEmailTaken($email)
    {
        $state['error'] = true;
        $req = $this->bdd()->prepare("SELECT count(*) FROM users WHERE email = :email");
        $req->execute(['email' => $email]);
        if ($req->fetchColumn() == 0) {
            $state['error'] = false;
            return $state;
        }
        $state['message'] = $this->__lang("email_taken");
        return $state;
    }

    public function isUsernameTaken($usr)
    {
        $state['error'] = true;
        $req = $this->bdd()->prepare("SELECT count(*) FROM users WHERE username = :username");
        $req->execute(['username' => $usr]);
        if ($req->fetchColumn() == 0) {
            $state['error'] = false;
            return $state;
        }
        $state['message'] = $this->__lang("username_taken");
        return $state;
    }

    public function validateUsername($usr) {
        $state['error'] = true;
        if (strlen($usr) < (int) '5' ) {
            $state['message'] = $this->__lang("username_short " . (int) '5' );
            return $state;
        } elseif (strlen($usr) > (int) '10' ) {
            $state['message'] = $this->__lang("username_long " . (int) '10' );
            return $state;
        }
        $state['error'] = false;
        return $state;
    }

    public function validatePassword($psw) {
        $state['error'] = true;
        if (strlen($psw) < (int) '5' ) {
            $state['message'] = $this->__lang("password_short " . (int) '5' );
            return $state;
        }
        $state['error'] = false;
        return $state;
    }

    public function validateEmail($email) {
        $state['error'] = true;
        if (strlen($email) < (int) '5' ) {
            $state['message'] = $this->__lang("email_short " . (int) '5' );
            return $state;
        } elseif (strlen($email) > (int) '50' ) {
            $state['message'] = $this->__lang("email_long " . (int) '50' );
            return $state;
        } elseif (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
            $state['message'] = $this->__lang("email_invalid", $email);
            return $state;
        }
        $state['error'] = false;
        return $state;
    }

    public function addUser($psw, $usr, $email)
    {
        $req = $this->bdd()->prepare("INSERT INTO users (username, password, email) VALUES (:username, :password, :email)");
        $psw_c = password_hash($psw, PASSWORD_BCRYPT);
        $req->execute(array("username" => $usr, "password" => $psw_c, "email" => $email));
    }

    public function connectUser($psw, $usr)
    {
        $req = $this->bdd()->prepare('SELECT * FROM users WHERE username = :username OR email = :username');
        $req->execute(['username' => $usr]);
        $user = $req->fetch();
        if(password_verify($psw, $user->password)){
            $state['error'] = false;
            return $state;
        }
        $state['error'] = true;
        return $state;
    }

    public function addSession($usr)
    {
        $req = $this->bdd()->prepare('SELECT * FROM users WHERE username = :username OR email = :username');
        $req->execute(['username' => $usr]);
        $auth = $req->fetch();
        if(session_status() == PHP_SESSION_NONE){
            session_start();
        }
        $_SESSION['auth'] = $auth;
    }

    public function delSession()
    {
        $_SESSION['auth'] = null;
        session_destroy();
    }

    public function register($psw, $psw_confirm, $usr, $email)
    {
        $state['message'] = true;

        //validate password
        $validatePassword = $this->validatePassword($psw);

        if ($validatePassword['error'] == 1) {
            $state['message'] = $validatePassword['message'];
            return $state;
        }
        if ($psw !== $psw_confirm) {
            $state['message'] = $this->__lang("password_no_match");
            return $state;
        }

        //validate username
        $validateUsername = $this->validateUsername($usr);
        $isUsernameTaken = $this->isUsernameTaken($usr);

        if ($validateUsername['error'] == 1) {
            $state['message'] = $validateUsername['message'];
            return $state;
        }
        if ($isUsernameTaken['error'] == 1) {
            $state['message'] = $isUsernameTaken['message'];
            return $state;
        }

        //validate email
        $validateEmail = $this->validateEmail($email);
        $isEmailTaken = $this->isEmailTaken($email);

        if ($validateEmail['error'] == 1) {
            $state['message'] = $this->__lang("email_invalid");
            return $state;
        }
        if ($isEmailTaken['error'] == 1) {
            $state['message'] = $validateUsername['message'];
            return $state;
        }

        //add user
        $this->addUser($psw, $usr, $email);

        //success message
        $state['message'] = false;
        $state['message'] = $this->__lang("register_success");
        return $state;

    }

    public function login($psw, $usr)
    {
        $state['message'] = true;

        //validate username
        $validateUsername = $this->validateUsername($usr);

        if ($validateUsername['error'] == 1)
        {
            $state['message'] = $this->__lang("account_username_invalid");
            return $state;

        }

        //validate password
        $validatePassword = $this->validatePassword($psw);

        if ($validatePassword['error'] == 1)
        {
            $state['message'] = $this->__lang("account_password_invalid");
            return $state;
        }

        //connect user
        $connectUser = $this->connectUser($psw, $usr);

        if ($connectUser['error'] == 1) {
            $state['message'] = $this->__lang("not_logged");
            return $state;
        }

        //session start
        $this->addSession($usr);

        $state['message'] = false;
        $state['message'] = $this->__lang("logged");
        return $state;

    }

}