from math import floor, ceil

from django.core.paginator import Paginator
from django.utils.functional import cached_property


class PostsPaginator(Paginator):
    """
    Paginator that returns that makes last item on page
    repeat as first item on next page.
    """
    def __init__(self, object_list, per_page, orphans=0,
                 allow_empty_first_page=True):
        per_page = int(per_page) - 1
        if orphans:
            orphans += 1
        super(PostsPaginator, self).__init__(
            object_list, per_page, orphans, allow_empty_first_page)

    def page(self, number):
        """
        Returns a Page object for the given 1-based page number.
        """
        number = self.validate_number(number)
        bottom = (number - 1) * self.per_page
        top = bottom + self.per_page + 1
        if top + self.orphans >= self.count:
            top = self.count
        return self._get_page(self.object_list[bottom:top], number, self)