Simple PHP Pagination Class

# Simple PHP Pagination Class

Simple PHP Pagination Class

Pagination.php

<?php

declare(strict_types=1);

namespace App\Domain\Model;

class Pagination
{
    const DEFAULT_ITEMS_PER_PAGE = 30;
    const DEFAULT_OFFSET_PAGES = 5;

    /** @var array */
    private $items;

    /** @var int */
    private $count;

    /** @var int */
    private $itemsPerPage;

    /** @var int */
    private $currentPage;

    /** @var int */
    private $totalPages;

    /** @var int */
    private $paginationOffset;

    public function __construct(array $items, int $itemsPerPage = self::DEFAULT_ITEMS_PER_PAGE, int $currentPage = 1)
    {
        $this->items = $items;
        $this->count = count($items);
        $this->itemsPerPage = $itemsPerPage;

        $this->currentPage = $currentPage;
        $this->totalPages = (int) ceil($this->count / $this->itemsPerPage);
        $this->paginationOffset = ($this->currentPage - 1) * $this->itemsPerPage;
    }

    public function apply(callable $callback)
    {
        $pagedItems = $this->paginateItems();

        foreach ($pagedItems as $index => $item) {
            $this->items[$index] = call_user_func($callback, $item);
        }
    }

    public function getItems(): array
    {
        return array_values($this->paginateItems());
    }

    public function getCurrentPage(): int
    {
        return $this->currentPage;
    }

    public function hasPreviousPage(): bool
    {
        return $this->currentPage > 1;
    }

    public function getPreviousPage(): ?int
    {
        $previousPage = ($this->hasPreviousPage() ? $this->currentPage - 1 : null);

        return $previousPage;
    }

    public function getPreviousPages(): array
    {
        if (!$this->hasPreviousPage()) {
            return [];
        }

        $leftPages = $this->currentPage - 1;
        $previousPagesCount = ($leftPages >= self::DEFAULT_OFFSET_PAGES ? self::DEFAULT_OFFSET_PAGES : $leftPages);

        $previousPages = range($this->getPreviousPage(), $this->currentPage - $previousPagesCount);
        asort($previousPages);

        return array_values($previousPages);
    }

    public function hasNextPage(): bool
    {
        return $this->currentPage < $this->totalPages;
    }

    public function getNextPage(): ?int
    {
        $nextPage = ($this->hasNextPage() ? $this->currentPage + 1 : null);

        return $nextPage;
    }

    public function getNextPages(): array
    {
        if (!$this->hasNextPage()) {
            return [];
        }

        $pendingPages = $this->totalPages - $this->currentPage;
        $nextPagesCount = ($pendingPages >= self::DEFAULT_OFFSET_PAGES ? self::DEFAULT_OFFSET_PAGES : $pendingPages);

        return range($this->getNextPage(), $this->currentPage + $nextPagesCount);
    }

    public function getTotalItems(): int
    {
        return $this->count;
    }

    public function getItemsPerPage(): int
    {
        return $this->itemsPerPage;
    }

    public function getTotalPages(): int
    {
        return $this->totalPages;
    }

    private function paginateItems()
    {
        return array_slice($this->items, $this->paginationOffset, $this->itemsPerPage, true);
    }
}