new: [custom pagination] component added

- simply paginate arrays as opposed to going to the DB for data
- just use $this->CustomPagination->paginate($array);

- it will automatically use the pagination options passed in the request
- compatible with the default cakePHP pagination helper

src/Controller/Component/CustomPaginationComponent.php

@@ -0,0 +1,103 @@
+<?php
+
+namespace App\Controller\Component;
+
+use Cake\Controller\Component;
+use Cake\Controller\ComponentRegistry;
+use Cake\Http\Exception\NotFoundException;
+use InvalidArgumentException;
+use Cake\Controller\Component\PaginatorComponent;
+use Cake\Utility\Hash;
+
+class CustomPaginationComponent extends Component
+{
+
+    public function __construct(ComponentRegistry $registry, array $config = [])
+    {
+        parent::__construct($registry, $config);
+    }
+
+    protected $defaults = [
+        'limit' => 10,
+        'direction' => 'asc'
+    ];
+
+    protected $settings = [
+
+    ];
+
+    protected $validFields = [
+        'limit',
+        'page',
+        'sort',
+        'direction'
+    ];
+
+    public function paginate(array $data): array
+    {
+
+        $request = $this->_registry->getController()->getRequest();
+        $params = $request->getQueryParams();
+        $settings = $this->defaults;
+        foreach ($this->validFields as $validField) {
+            if (isset($params[$validField])) {
+                $settings[$validField] = $params[$validField];
+            }
+        }
+        $count = count($data);
+        if (!empty($settings['sort'])) {
+            $data = $this->_sortData($data, $settings);
+        }
+        if (!empty($settings['limit'])) {
+            $data = $this->_truncateData($data, $settings);
+        }
+        $this->_setPagingParams($settings, $count, count($data));
+        return $data;
+    }
+
+    protected function _sortData(array $data, array &$settings): array
+    {
+        return Hash::sort($data, '{n}.' . $settings['sort'], strtolower($settings['direction']));
+    }
+
+    protected function _truncateData(array $data, array $settings): array
+    {
+        $page = $settings['page'] ?? 1;
+        $limit = $settings['limit'] ?? 50;
+        $offset = ($page - 1) * $limit;
+        return array_slice($data, $offset, $limit);
+    }
+
+    protected function _setPagingParams(array $settings, int $count, int $currentCount): void
+    {
+        $controller = $this->getController();
+        $request = $controller->getRequest();
+        $limit = $settings['limit'] ?? 0;
+        $pageCount = empty($settings['limit']) ? 1 : ceil($count/$limit);
+        $page = $settings['page'] ?? 1;
+        $start = $end = 0;
+        $prevPage = $page > 1;
+        $nextPage = true;
+        if ($count) {
+            $nextPage = $count > ($page * $limit);
+        }
+        if ($currentCount > 0) {
+            $start = (($page - 1) * $limit) + 1;
+            $end = $start + $currentCount - 1;
+        }
+        $paging = [
+            'count' => $count,
+            'current' => $currentCount,
+            'perPage' => $limit,
+            'page' => $page,
+            'requestedPage' => $settings['page'] ?? 1,
+            'pageCount' => $pageCount,
+            'start' => $start,
+            'end' => $end,
+            'prevPage' => $page > 1,
+            'nextPage' => $nextPage
+        ];
+        $paging = ['organisations' => $paging + $settings];
+        $controller->setRequest($request->withAttribute('paging', $paging));
+    }
+}