Files
lichterei-web/kirby/src/Toolkit/Pagination.php
Bastian Allgeier 01277f79f2 first version
2019-01-13 23:17:34 +01:00

411 lines
8.3 KiB
PHP
Executable File

<?php
namespace Kirby\Toolkit;
use Exception;
/**
* Basic pagination handling
*/
class Pagination
{
/**
* The current page
*
* @var integer
*/
protected $page;
/**
* Total number of items
*
* @var integer
*/
protected $total;
/**
* The number of items per page
*
* @var integer
*/
protected $limit;
/**
* Creates a new pagination object
* with the given parameters
*
* @param array $params
*/
public function __construct(array $params = [])
{
$this->page($params['page'] ?? 1);
$this->limit($params['limit'] ?? 20);
$this->total($params['total'] ?? 0);
}
/**
* Creates a pagination instance for the given
* collection with a flexible argument api
*
* @param Collection $collection
* @param ...mixed $arguments
* @return self
*/
public static function for(Collection $collection, ...$arguments)
{
$a = $arguments[0] ?? null;
$b = $arguments[1] ?? null;
$params = [];
if (is_array($a) === true) {
/**
* First argument is an option array
*
* $collection->paginate([...])
*/
$params = $a;
} elseif (is_int($a) === true && $b === null) {
/**
* First argument is the limit
*
* $collection->paginate(10)
*/
$params['limit'] = $a;
} elseif (is_int($a) === true && is_int($b) === true) {
/**
* First argument is the limit,
* second argument is the page
*
* $collection->paginate(10, 2)
*/
$params['limit'] = $a;
$params['page'] = $b;
} elseif (is_int($a) === true && is_array($b) === true) {
/**
* First argument is the limit,
* second argument are options
*
* $collection->paginate(10, [...])
*/
$params = $b;
$params['limit'] = $a;
}
// add the total count from the collection
$params['total'] = $collection->count();
// remove null values to make later merges work properly
$params = array_filter($params);
// create the pagination instance
return new static($params);
}
/**
* Getter and setter for the current page
*
* @param int|null $page
* @return int|Pagination
*/
public function page(int $page = null)
{
if ($page === null) {
if ($this->page > $this->pages()) {
$this->page = $this->lastPage();
}
if ($this->page < 1) {
$this->page = $this->firstPage();
}
return $this->page;
}
$this->page = $page;
return $this;
}
/**
* Getter and setter for the total number of items
*
* @param int|null $total
* @return int|Pagination
*/
public function total(int $total = null)
{
if ($total === null) {
return $this->total;
}
if ($total < 0) {
throw new Exception('Invalid total number of items: ' . $total);
}
$this->total = $total;
return $this;
}
/**
* Getter and setter for the number of items per page
*
* @param int|null $limit
* @return int|Pagination
*/
public function limit(int $limit = null)
{
if ($limit === null) {
return $this->limit;
}
if ($limit < 1) {
throw new Exception('Invalid pagination limit: ' . $limit);
}
$this->limit = $limit;
return $this;
}
/**
* Returns the index of the first item on the page
*
* @return int
*/
public function start(): int
{
$index = $this->page() - 1;
if ($index < 0) {
$index = 0;
}
return $index * $this->limit() + 1;
}
/**
* Returns the index of the last item on the page
*
* @return int
*/
public function end(): int
{
$value = ($this->start() - 1) + $this->limit();
if ($value <= $this->total()) {
return $value;
}
return $this->total();
}
/**
* Returns the total number of pages
*
* @return int
*/
public function pages(): int
{
if ($this->total() === 0) {
return 0;
}
return ceil($this->total() / $this->limit());
}
/**
* Returns the first page
*
* @return int
*/
public function firstPage(): int
{
return $this->total() === 0 ? 0 : 1;
}
/**
* Returns the last page
*
* @return int
*/
public function lastPage(): int
{
return $this->pages();
}
/**
* Returns the offset (i.e. for db queries)
*
* @return int
*/
public function offset(): int
{
return $this->start() - 1;
}
/**
* Checks if the given page exists
*
* @return boolean
*/
public function hasPage(int $page): bool
{
if ($page <= 0) {
return false;
}
if ($page > $this->pages()) {
return false;
}
return true;
}
/**
* Checks if there are any pages at all
*
* @return boolean
*/
public function hasPages(): bool
{
return $this->total() > $this->limit();
}
/**
* Checks if there's a previous page
*
* @return boolean
*/
public function hasPrevPage(): bool
{
return $this->page() > 1;
}
/**
* Returns the previous page
*
* @return int|null
*/
public function prevPage()
{
return $this->hasPrevPage() ? $this->page() - 1 : null;
}
/**
* Checks if there's a next page
*
* @return boolean
*/
public function hasNextPage(): bool
{
return $this->end() < $this->total();
}
/**
* Returns the next page
*
* @return int|null
*/
public function nextPage()
{
return $this->hasNextPage() ? $this->page() + 1 : null;
}
/**
* Checks if the current page is the first page
*
* @return boolean
*/
public function isFirstPage(): bool
{
return $this->page() === $this->firstPage();
}
/**
* Checks if the current page is the last page
*
* @return boolean
*/
public function isLastPage(): bool
{
return $this->page() === $this->lastPage();
}
/**
* Creates a range of page numbers for Google-like pagination
*
* @return array
*/
public function range(int $range = 5): array
{
$page = $this->page();
$pages = $this->pages();
$start = 1;
$end = $pages;
if ($pages <= $range) {
return range($start, $end);
}
$start = $page - (int)floor($range/2);
$end = $page + (int)floor($range/2);
if ($start <= 0) {
$end += abs($start);
$start = 1;
}
if ($end > $pages) {
$start -= $end - $pages;
$end = $pages;
}
return range($start, $end);
}
/**
* Returns the first page of the created range
*
* @return int
*/
public function rangeStart(int $range = 5): int
{
return $this->range($range)[0];
}
/**
* Returns the last page of the created range
*
* @return int
*/
public function rangeEnd(int $range = 5): int
{
$range = $this->range($range);
return array_pop($range);
}
/**
* Returns an array with all properties
*
* @return array
*/
public function toArray(): array
{
return [
'page' => $this->page(),
'firstPage' => $this->firstPage(),
'lastPage' => $this->lastPage(),
'pages' => $this->pages(),
'offset' => $this->offset(),
'limit' => $this->limit(),
'total' => $this->total(),
'start' => $this->start(),
'end' => $this->end(),
];
}
}