Not every person on Internet is honest and kind. So: it's best to allow to edito your page only persons you trust.
You can protect /edit.php script with the following .htaccess file:
Options -Indexes
AuthType Basic
AuthName "Aplikacja.info - CMSWIKI"
AuthUserFile "/your-path-to-htpasswd-dir/.htpasswd"
DirectoryIndex view.php
<Files "edit.php">
require user dci
</Files>
When attemting to edit current page you will be asked for login & password. An instruction how to generate .htapsswd file:
htpasswd -b -c /your-path-to-htpasswd-dir/.htpasswd \ login password