Adds helper for retrieving input state data from view_submission

Author: jeremeamia

src/Contexts/InputState.php

@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SlackPhp\Framework\Contexts;
+
+use JsonSerializable;
+use SlackPhp\Framework\Context;
+
+/**
+ * Normalizes state data from all input types in `view_submission`s to key-value pairs.
+ */
+class InputState implements JsonSerializable
+{
+    use HasData;
+
+    /**
+     * Creates the InputState by extracting the data from the Context.
+     *
+     * @param Context $context
+     * @return self
+     */
+    public static function fromContext(Context $context): self
+    {
+        return new self($context->payload()->getState()->toArray());
+    }
+
+    public function __construct(array $stateData)
+    {
+        $data = [];
+        foreach ($stateData as $blockId => $input) {
+            $elem = reset($input);
+            $data[$blockId] = $elem['value']
+                ?? $elem['selected_option']['value']
+                ?? $elem['selected_date']
+                ?? $elem['selected_time']
+                ?? $elem['selected_user']
+                ?? $elem['selected_conversation']
+                ?? $elem['selected_channel']
+                ?? null;
+            if ($data[$blockId] !== null) {
+                continue;
+            }
+
+            if (isset($elem['selected_options'])) {
+                $data[$blockId] = array_column($elem['selected_options'], 'value');
+                continue;
+            }
+
+            $data[$blockId] = $elem['selected_users']
+                ?? $elem['selected_conversations']
+                ?? $elem['selected_channels']
+                ?? null;
+        }
+
+        $this->setData($data);
+    }
+}