import math
from kivy.uix.screenmanager import Screen
from kivy.clock import Clock
from kivy.metrics import dp


COLS = 7
BTN_W = dp(150)
BTN_H = dp(120)
SP = dp(10)
PAD = dp(10)


class BaseAccountSelectScreen(Screen):
    def _create_ucet_button(self, u):
        raise NotImplementedError(
            "_create_ucet_button must be implemented in subclass"
        )
 
    def _load_ucty(self, ucty):
        self.grid.clear_widgets()
        for u in ucty:
            if not u.stul:
                continue
            btn = self._create_ucet_button(u)
            self.grid.add_widget(btn)
        Clock.schedule_once(self._update_scroll, 0)
    def _update_scroll(self, *_):
        if not self.scroll or not self.grid:
            return
        count = len(self.grid.children)
        if count == 0:
            self.scroll.do_scroll_x = False
            self.scroll.do_scroll_y = False
            return
        rows = math.ceil(count / COLS)
        content_h = rows * BTN_H + (rows - 1) * SP + 2 * PAD
        self.scroll.do_scroll_y = content_h > self.scroll.height