"use client";

import {
  Pagination,
  PaginationContent,
  PaginationEllipsis,
  PaginationItem,
  PaginationLink,
  PaginationNext,
  PaginationPrevious,
} from "@/components/ui/pagination";
import { PAGE_SIZE } from "@/lib/constants/pagination";

type ListPaginationProps = {
  page: number;
  totalPages: number;
  total: number;
  pageSize?: number;
  onPageChange: (page: number) => void;
};

function pageRange(current: number, total: number): (number | "ellipsis")[] {
  if (total <= 7) {
    return Array.from({ length: total }, (_, i) => i + 1);
  }
  if (current <= 4) {
    return [1, 2, 3, 4, 5, "ellipsis", total];
  }
  if (current >= total - 3) {
    return [1, "ellipsis", total - 4, total - 3, total - 2, total - 1, total];
  }
  return [1, "ellipsis", current - 1, current, current + 1, "ellipsis", total];
}

export function ListPagination({
  page,
  totalPages,
  total,
  pageSize = PAGE_SIZE,
  onPageChange,
}: ListPaginationProps) {
  if (total <= pageSize) return null;

  const start = (page - 1) * pageSize + 1;
  const end = Math.min(page * pageSize, total);
  const pages = pageRange(page, totalPages);

  return (
    <div className="flex flex-col gap-3 px-4 py-3 border-t border-zinc-100">
      <p className="text-sm text-zinc-500 text-center sm:text-left">
        Showing {start}–{end} of {total}
      </p>
      <Pagination>
        <PaginationContent>
          <PaginationItem>
            <PaginationPrevious
              disabled={page <= 1}
              onClick={() => page > 1 && onPageChange(page - 1)}
            />
          </PaginationItem>
          {pages.map((p, i) =>
            p === "ellipsis" ? (
              <PaginationItem key={`ellipsis-${i}`}>
                <PaginationEllipsis />
              </PaginationItem>
            ) : (
              <PaginationItem key={p}>
                <PaginationLink
                  isActive={p === page}
                  onClick={() => onPageChange(p)}
                >
                  {p}
                </PaginationLink>
              </PaginationItem>
            ),
          )}
          <PaginationItem>
            <PaginationNext
              disabled={page >= totalPages}
              onClick={() => page < totalPages && onPageChange(page + 1)}
            />
          </PaginationItem>
        </PaginationContent>
      </Pagination>
    </div>
  );
}