Subversion-Projekte lars-tiefland.laravel_shop

<?php

/**
 * This file is part of the Nette Framework (https://nette.org)
 * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
 */

declare(strict_types=1);

namespace Nette\Utils;

use Nette;


/**
 * Paginating math.
 *
 * @property   int $page
 * @property-read int $firstPage
 * @property-read int|null $lastPage
 * @property-read int $firstItemOnPage
 * @property-read int $lastItemOnPage
 * @property   int $base
 * @property-read bool $first
 * @property-read bool $last
 * @property-read int|null $pageCount
 * @property   int $itemsPerPage
 * @property   int|null $itemCount
 * @property-read int $offset
 * @property-read int|null $countdownOffset
 * @property-read int $length
 */
class Paginator
{
        use Nette\SmartObject;

        private int $base = 1;
        private int $itemsPerPage = 1;
        private int $page = 1;
        private ?int $itemCount = null;


        /**
         * Sets current page number.
         */
        public function setPage(int $page): static
        {
                $this->page = $page;
                return $this;
        }


        /**
         * Returns current page number.
         */
        public function getPage(): int
        {
                return $this->base + $this->getPageIndex();
        }


        /**
         * Returns first page number.
         */
        public function getFirstPage(): int
        {
                return $this->base;
        }


        /**
         * Returns last page number.
         */
        public function getLastPage(): ?int
        {
                return $this->itemCount === null
                        ? null
                        : $this->base + max(0, $this->getPageCount() - 1);
        }


        /**
         * Returns the sequence number of the first element on the page
         */
        public function getFirstItemOnPage(): int
        {
                return $this->itemCount !== 0
                        ? $this->offset + 1
                        : 0;
        }


        /**
         * Returns the sequence number of the last element on the page
         */
        public function getLastItemOnPage(): int
        {
                return $this->offset + $this->length;
        }


        /**
         * Sets first page (base) number.
         */
        public function setBase(int $base): static
        {
                $this->base = $base;
                return $this;
        }


        /**
         * Returns first page (base) number.
         */
        public function getBase(): int
        {
                return $this->base;
        }


        /**
         * Returns zero-based page number.
         */
        protected function getPageIndex(): int
        {
                $index = max(0, $this->page - $this->base);
                return $this->itemCount === null
                        ? $index
                        : min($index, max(0, $this->getPageCount() - 1));
        }


        /**
         * Is the current page the first one?
         */
        public function isFirst(): bool
        {
                return $this->getPageIndex() === 0;
        }


        /**
         * Is the current page the last one?
         */
        public function isLast(): bool
        {
                return $this->itemCount === null
                        ? false
                        : $this->getPageIndex() >= $this->getPageCount() - 1;
        }


        /**
         * Returns the total number of pages.
         */
        public function getPageCount(): ?int
        {
                return $this->itemCount === null
                        ? null
                        : (int) ceil($this->itemCount / $this->itemsPerPage);
        }


        /**
         * Sets the number of items to display on a single page.
         */
        public function setItemsPerPage(int $itemsPerPage): static
        {
                $this->itemsPerPage = max(1, $itemsPerPage);
                return $this;
        }


        /**
         * Returns the number of items to display on a single page.
         */
        public function getItemsPerPage(): int
        {
                return $this->itemsPerPage;
        }


        /**
         * Sets the total number of items.
         */
        public function setItemCount(?int $itemCount = null): static
        {
                $this->itemCount = $itemCount === null ? null : max(0, $itemCount);
                return $this;
        }


        /**
         * Returns the total number of items.
         */
        public function getItemCount(): ?int
        {
                return $this->itemCount;
        }


        /**
         * Returns the absolute index of the first item on current page.
         */
        public function getOffset(): int
        {
                return $this->getPageIndex() * $this->itemsPerPage;
        }


        /**
         * Returns the absolute index of the first item on current page in countdown paging.
         */
        public function getCountdownOffset(): ?int
        {
                return $this->itemCount === null
                        ? null
                        : max(0, $this->itemCount - ($this->getPageIndex() + 1) * $this->itemsPerPage);
        }


        /**
         * Returns the number of items on current page.
         */
        public function getLength(): int
        {
                return $this->itemCount === null
                        ? $this->itemsPerPage
                        : min($this->itemsPerPage, $this->itemCount - $this->getPageIndex() * $this->itemsPerPage);
        }
}