Add pagination functionality (#15)

* Add methods to get http request/response headers fro the last api call

* Add pagination functionality and tests

* Update README and CHANGELOG

CHANGELOG.md

@@ -2,6 +2,24 @@
 
 All Notable changes for the Laravel 5 WooCommerce REST API Client  will be documented in this file
 
+## 2.3.0
+- Add pagination functionality.
+Now these functions are available
+    - totalResults()
+    - firstPage()
+    - lastPage()
+    - currentPage()
+    - totalPages()
+    - previousPage()
+    - nextPage()
+    - hasPreviousPage()
+    - hasNextPage()
+    - hasNotPreviousPage()
+    - hasNotNextPage()
+- Get the Request & Response (Headers) from the last request
+    - getRequest()
+    - getResponse()
+
 ## 2.2.0
 - Laravel 5.4 compatibility
 

README.md

@@ -152,6 +152,54 @@ $data = [
 return Woocommerce::put('products/1', $data);
 ```
 
+### Pagination
+So you don't have to mess around with the request and response header and the calculations this wrapper will do all the heavy lifting for you.
+(WC 2.6.x or later, WP 4.4 or later) 
+
+```php
+use Woocommerce;
+
+// assuming we have 474 orders in pur result
+// we will request page 5 with 25 results per page
+$params = [
+    'per_page' => 25,
+    'page' => 5
+];
+
+Woocommerce::get('orders', $params);
+
+Woocommerce::totalResults(); // 474
+Woocommerce::firstPage(); // 1
+Woocommerce::lastPage(); // 19
+Woocommerce::currentPage(); // 5 
+Woocommerce::totalPages(); // 19
+Woocommerce::previousPage(); // 4
+Woocommerce::nextPage(); // 6
+Woocommerce::hasPreviousPage(); // true 
+Woocommerce::hasNextPage(); // true
+Woocommerce::hasNotPreviousPage(); // false 
+Woocommerce::hasNotNextPage(); // false
+```
+
+### HTTP Request & Response (Headers)
+
+```php
+use Woocommerce;
+
+// first send a request
+Woocommerce::get('orders');
+
+// get the request
+Woocommerce::getRequest();
+
+// get the response headers
+Woocommerce::getResponse();
+
+// get the total number of results
+Woocommerce::getResponse()->getHeaders()['X-WP-Total']
+```
+
+
 ### More Examples
 Refer to [WooCommerce REST API Documentation](https://woocommerce.github.io/woocommerce-rest-api-docs) for more examples and documention.
 

src/WoocommerceClient.php

@@ -70,4 +70,146 @@ public function delete($endpoint, $parameters = [])
     {
         return $this->client->delete($endpoint, $parameters);
     }
+
+    /**
+     * Get the http request header from the last request
+     *
+     * @return \Automattic\WooCommerce\HttpClient\Request
+     */
+    public function getRequest()
+    {
+        return $this->client->http->getRequest();
+    }
+
+    /**
+     * Get the http response headers from the last request
+     *
+     * @return \Automattic\WooCommerce\HttpClient\Response
+     */
+    public function getResponse()
+    {
+        return $this->client->http->getResponse();
+    }
+
+    /**
+     * Return the first page number of the result
+     *
+     * @return int
+     */
+    public function firstPage()
+    {
+        return 1;
+    }
+
+    /**
+     * Return the last page number of the result
+     *
+     * @return int
+     */
+    public function lastPage()
+    {
+        return $this->totalPages();
+    }
+
+    /**
+     * Return the current page number of the result
+     *
+     * @return int
+     */
+    public function currentPage()
+    {
+        return !empty($this->getRequest()->getParameters()['page']) ? $this->getRequest()->getParameters()['page'] : 1;
+    }
+
+    /**
+     * Return the total number of results
+     *
+     * @return int
+     */
+    public function totalResults()
+    {
+        return (int)$this->getResponse()->getHeaders()['X-WP-Total'];
+    }
+
+    /**
+     * Return the total number of pages for this result
+     *
+     * @return mixed
+     */
+    public function totalPages()
+    {
+        return (int)$this->getResponse()->getHeaders()['X-WP-TotalPages'];
+    }
+
+    /**
+     * Return the previous page number for the current page
+     * Will be null if there's no previous page
+     *
+     * @return int|null
+     */
+    public function previousPage()
+    {
+        $previous_page = $this->currentPage() - 1;
+        if ($previous_page < 1) {
+            $previous_page = null;
+        }
+
+        return $previous_page;
+    }
+
+    /**
+     * Return the next page number for the current page
+     * Will be null if there's no next page
+     *
+     * @return int|null
+     */
+    public function nextPage()
+    {
+        $next_page = $this->currentPage() + 1;
+        if ($next_page > $this->totalPages()) {
+            $next_page = null;
+        }
+
+        return $next_page;
+    }
+
+    /**
+     * Returns true if there's a next page
+     *
+     * @return bool
+     */
+    public function hasNextPage()
+    {
+        return (bool)$this->nextPage();
+    }
+
+    /**
+     * Returns true if there's a previous page
+     *
+     * @return bool
+     */
+    public function hasPreviousPage()
+    {
+        return (bool)$this->previousPage();
+    }
+
+    /**
+     * Returns true if there's no next page
+     *
+     * @return bool
+     */
+    public function hasNotNextPage()
+    {
+        return (bool)!$this->nextPage();
+    }
+
+    /**
+     * Returns true if there's no previous page
+     *
+     * @return bool
+     */
+    public function hasNotPreviousPage()
+    {
+        return (bool)!$this->previousPage();
+    }
 }