Added better header parsing to Request-class.

- Added `tryParse` argument to the `getHeader` method. When enabled the method will try to parse headers from both server and client-side (enabled by default).
- Simplified references that checks for both variants of header (http/non http).
- Simplified getIp method of the Request-class.

src/Pecee/Http/Request.php

@@ -4,6 +4,7 @@ namespace Pecee\Http;
 
 use Pecee\Http\Exceptions\MalformedUrlException;
 use Pecee\Http\Input\InputHandler;
+use Pecee\Http\Middleware\BaseCsrfVerifier;
 use Pecee\SimpleRouter\Route\ILoadableRoute;
 use Pecee\SimpleRouter\Route\RouteUrl;
 use Pecee\SimpleRouter\SimpleRouter;
@@ -110,14 +111,14 @@ class Request
     {
         foreach ($_SERVER as $key => $value) {
             $this->headers[strtolower($key)] = $value;
-            $this->headers[strtolower(str_replace('_', '-', $key))] = $value;
+            $this->headers[str_replace('_', '-', strtolower($key))] = $value;
         }
 
         $this->setHost($this->getHeader('http-host'));
 
         // Check if special IIS header exist, otherwise use default.
         $this->setUrl(new Url($this->getHeader('unencoded-url', $this->getHeader('request-uri'))));
-        
+
         $this->method = strtolower($this->getHeader('request-method'));
         $this->inputHandler = new InputHandler($this);
         $this->method = strtolower($this->inputHandler->value('_method', $this->getHeader('request-method')));
@@ -186,7 +187,7 @@ class Request
      */
     public function getCsrfToken(): ?string
     {
-        return $this->getHeader('x-csrf-token') ?? $this->getHeader('http-x-csrf-token');
+        return $this->getHeader(BaseCsrfVerifier::HEADER_KEY);
     }
 
     /**
@@ -204,15 +205,13 @@ class Request
      */
     public function getIp(): ?string
     {
-        if ($this->getHeader('http-cf-connecting-ip') !== null) {
-            return $this->getHeader('http-cf-connecting-ip');
-        }
-
-        if ($this->getHeader('http-x-forwarded-for') !== null) {
-            return $this->getHeader('http-x-forwarded-for');
-        }
-
-        return $this->getHeader('remote-addr');
+        return $this->getHeader(
+            'http-cf-connecting-ip',
+            $this->getHeader(
+                'http-x-forwarded-for',
+                $this->getHeader('remote-addr')
+            )
+        );
     }
 
     /**
@@ -247,14 +246,28 @@ class Request
     /**
      * Get header value by name
      *
-     * @param string $name
-     * @param string|null $defaultValue
+     * @param string $name Name of the header.
+     * @param string|null $defaultValue Value to be returned if header is not found.
+     * @param bool $tryParse When enabled the method will try to find the header from both from client (http) and server-side variants, if the header is not found.
      *
      * @return string|null
      */
-    public function getHeader($name, $defaultValue = null): ?string
+    public function getHeader(string $name, $defaultValue = null, $tryParse = true): ?string
     {
-        return $this->headers[strtolower($name)] ?? $defaultValue;
+        $name = strtolower($name);
+        $header = $this->headers[$name] ?? null;
+
+        if ($tryParse === true && $header === null) {
+            if (strpos($name, 'http-') === 0) {
+                // Trying to find client header variant which was not found, searching for header variant without http- prefix.
+                $header = $this->headers[str_replace('http-', '', $name)] ?? null;
+            } else {
+                // Trying to find server variant which was not found, searching for client variant with http- prefix.
+                $header = $this->headers['http-' . $name] ?? null;
+            }
+        }
+
+        return $header ?? $defaultValue;
     }
 
     /**