1 files changed, 59 insertions, 0 deletions
diff --git a/vendor/ipl/web/src/Common/FormUid.php b/vendor/ipl/web/src/Common/FormUid.php
new file mode 100644
index 0000000..05aac7b
--- /dev/null
+++ b/vendor/ipl/web/src/Common/FormUid.php
@@ -0,0 +1,59 @@
+<?php
+
+namespace ipl\Web\Common;
+
+use ipl\Html\Form;
+use ipl\Html\Contract\FormElement;
+use LogicException;
+
+trait FormUid
+{
+    protected $uidElementName = 'uid';
+
+    /**
+     * Create a form element to make this form distinguishable from others
+     *
+     * You'll have to define a name for the form for this to work.
+     *
+     * @return FormElement
+     */
+    protected function createUidElement()
+    {
+        /** @var Form $this */
+        $element = $this->createElement('hidden', $this->uidElementName, ['ignore' => true]);
+        $element->getAttributes()->registerAttributeCallback('value', function () {
+            /** @var Form $this */
+            return $this->getAttributes()->get('name')->getValue();
+        });
+
+        return $element;
+    }
+
+    /**
+     * Get whether the form has been sent
+     *
+     * A form is considered sent if the request's method equals the form's method
+     * and the sent UID is the form's UID.
+     *
+     * @return bool
+     */
+    public function hasBeenSent()
+    {
+        if (! parent::hasBeenSent()) {
+            return false;
+        } elseif ($this->getMethod() === 'GET') {
+            // Get forms are unlikely to require a UID. If they do, change this.
+            return true;
+        }
+
+        /** @var Form $this */
+        $name = $this->getAttributes()->get('name')->getValue();
+        if (! $name) {
+            throw new LogicException('Form has no name');
+        }
+
+        $values = $this->getRequest()->getParsedBody();
+
+        return isset($values[$this->uidElementName]) && $values[$this->uidElementName] === $name;
+    }
+}