app.py

from PyQt5.QtWidgets import QApplication

from printer_tool.registration import LicenseStore, get_machine_code, validate_registration_token
from printer_tool.registration_ui import RegistrationDialog
from printer_tool.runtime_icon import apply_application_icon
from printer_tool.ui import MainWindow


def main() -> int:
    app = QApplication.instance() or QApplication([])
    apply_application_icon(app, "PrinterTool.ico", app_id="PrinterTool.Main")
    store = LicenseStore()
    machine_code = get_machine_code()
    valid, _, _ = validate_registration_token(store.load(), machine_code)

    if not valid:
        dialog = RegistrationDialog(store=store, machine_code=machine_code)
        if dialog.exec_() != dialog.Accepted:
            return 0

    window = MainWindow()
    window.show()
    return app.exec_()


if __name__ == "__main__":
    raise SystemExit(main())