Feature: add check for application/json in headers accept (#6857)

* feature: add check for multipart/form-data

* refactor: cleanup logic

* docs: add since tag and descriptions

* refactor: check headers for accept bbefore content-type

* docs: update since tag

---------

Co-authored-by: Jon Waldstein <[email protected]>

src/Framework/PaymentGateways/Traits/HandleHttpResponses.php

@@ -11,6 +11,7 @@ trait HandleHttpResponses
     /**
      * Handle Response
      *
+     * @unreleased added check for responding with json
      * @since 2.27.0 add support for json content-type
      * @since 2.18.0
      *
@@ -19,7 +20,7 @@ trait HandleHttpResponses
     public function handleResponse($type)
     {
         if ($type instanceof RedirectResponse) {
-            if (isset($_SERVER['CONTENT_TYPE']) && str_contains($_SERVER['CONTENT_TYPE'], "application/json")) {
+            if ($this->wantsJson()) {
                 wp_send_json([
                     'type' => 'redirect',
                     'data' => [
@@ -60,4 +61,20 @@ public function handleExceptionResponse(\Exception $exception, string $message)
         give_set_error('PaymentGatewayException', $message);
         give_send_back_to_checkout();
     }
+
+    /**
+     * This checks the server headers for 'application/json' to determine if it should respond with json.
+     *
+     * @unreleased
+     *
+     * @return bool
+     */
+    protected function wantsJson(): bool
+    {
+        if (isset($_SERVER['HTTP_ACCEPT']) && str_contains($_SERVER['HTTP_ACCEPT'], 'application/json')) {
+            return true;
+        }
+
+        return isset($_SERVER['CONTENT_TYPE']) && str_contains($_SERVER['CONTENT_TYPE'], 'application/json');
+    }
 }