A simple pagination function in php.

paginate.php

<?php
public static function paginate(int $totalItems, int $offset, int $size)
{
    $pages = [];
    $i = 0;
    $pageNumber = 1;
    while ($i <= ($totalItems - $size)) {
        $page['number'] = $pageNumber;
        $page['offset'] = $i;
        $page['size'] = $size;
        $page['first_page'] = false;
        $page['last_page'] = false;
        if ($i === $offset) {
            $page['current'] = true;
        } else {
            $page['current'] = false;
        }
        $pages[] = $page;
        $pageNumber++;
        $i = $i + $size;
    }
    $pages[0]['first_page'] = true;
    $pages[count($pages) - 1]['last_page'] = true;

    // Limit how many page numbers we show.
    $pageCount = count($pages);
    if ($pageCount > 15) {
        $firstPage = [$pages[0]];
        $lastPage = [$pages[$pageCount - 1]];
        $firstFive = array_slice($pages, 0, 5, true);
        $lastFive = array_slice($pages, $pageCount - 5, 5, true);
        $currentPage = $offset / $size;
        if ($offset !== 0 && !($offset >= ($totalItems - (5 * $size)))) {
            $middleFive = array_slice($pages, $currentPage - 2, 5, true);
            $middleThree = array_slice($pages, $currentPage - 1, 3, true);
        } else {
            $middleFive = array_slice(
              $pages,
              ceil(($pageCount / 2) - 2),
              5,
              true
            );
            $middleThree = array_slice(
              $pages,
              ceil(($pageCount / 2) - 1),
              3,
              true
            );
        }
        $dotsOne = ['dotsOne' => '...'];
        $dotsTwo = ['dotsTwo' => '...'];
        if (($offset <= ($size * 4))) {
            $listOfPages = array_merge(
              $firstFive,
              $dotsOne,
              $middleThree,
              $dotsTwo,
              $lastPage
            );
        } elseif ((($offset + ($size * 5)) >= $totalItems)) {
            $listOfPages = array_merge(
              $firstPage,
              $dotsOne,
              $middleThree,
              $dotsTwo,
              $lastFive
            );
        } else {
            $listOfPages = array_merge(
              $firstPage,
              $dotsOne,
              $middleFive,
              $dotsTwo,
              $lastPage
            );
        }
        return $listOfPages;
    } else {
        return $pages;
    }
}