tao-test/app/taoClientDiagnostic/model/diagnostic/Paginator.php

105 lines
3.4 KiB
PHP

<?php
/**
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; under version 2
* of the License (non-upgradable).
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright (c) 2017 (original work) Open Assessment Technologies SA ;
*
*/
namespace oat\taoClientDiagnostic\model\diagnostic;
use oat\taoClientDiagnostic\model\storage\PaginatedStorage;
/**
* Provides common data helper for datatable component.
*/
class Paginator
{
/**
* The default number of rows displayed in a page
*/
const DEFAULT_ROWS = 25;
/**
* The index of the default page
*/
const DEFAULT_PAGE = 1;
/**
* The index of the option providing the number of rows per page
*/
const OPTION_ROWS = 'rows';
/**
* The index of the option providing the page number
*/
const OPTION_PAGE = 'page';
/**
* The index of the option providing the page filter
*/
const OPTION_FILTER = 'filter';
/**
* Paginates a collection to render a subset in a table
*
* @param array|PaginatedStorage $collection - The full amount of lines to paginate
* @param array [$options] - Allow to setup the page. These options are supported:
* - self::OPTION_ROWS : The number of rows per page
* - self::OPTION_PAGE : The index of the page to get
* @param function [$dataRenderer] - An optional callback function provided to format the paginated data
* @return array
*/
public function paginate($collection, $options = array(), $dataRenderer = null)
{
$optRows = abs(intval(isset($options[self::OPTION_ROWS]) ? $options[self::OPTION_ROWS] : self::DEFAULT_ROWS));
$optPage = abs(intval(isset($options[self::OPTION_PAGE]) ? $options[self::OPTION_PAGE] : self::DEFAULT_PAGE));
$optFilter = isset($options[self::OPTION_FILTER]) ? $options[self::OPTION_FILTER] : null;
if ($collection instanceof PaginatedStorage) {
$amount = $collection->count($optFilter);
$paginatedStorage = true;
} else {
$amount = count($collection);
$paginatedStorage = false;
}
$rows = max(1, $optRows);
$total = ceil($amount / $rows);
$page = max(1, min($optPage, $total));
$offset = ($page - 1) * $rows;
$result = array(
'offset' => $offset,
'amount' => $amount,
'total' => $total,
'page' => $page,
'rows' => $rows
);
if ($paginatedStorage) {
$result['data'] = $collection->findPage($page, $rows, $optFilter);
} else {
$result['data'] = array_slice($collection, $offset, $rows);
}
if (is_callable($dataRenderer)) {
$result['data'] = $dataRenderer($result['data']);
}
$result['length'] = count($result['data']);
return $result;
}
}