simple tree builder

src/Simple/TreeBuilder.php

@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Dakujem\Oliva\Simple;
+
+use Dakujem\Oliva\MovableNodeContract;
+use Dakujem\Oliva\TreeNodeContract;
+use LogicException;
+
+/**
+ * Simple tree builder.
+ * Wraps data that is already structured into tree node classes.
+ *
+ * @author Andrej Rypak <[email protected]>
+ */
+class TreeBuilder
+{
+    public function build(
+        mixed $data,
+        callable $node,
+        callable $children,
+    ): TreeNodeContract {
+        return $this->buildNode(
+            data: $data,
+            nodeFactory: $node,
+            childrenExtractor: $children,
+        );
+    }
+
+    public function buildNode(
+        mixed $data,
+        callable $nodeFactory,
+        callable $childrenExtractor,
+    ): MovableNodeContract {
+        // Create a node using the provided factory.
+        $node = $nodeFactory($data);
+
+        // Check for consistency.
+        if (!$node instanceof MovableNodeContract) {
+            // TODO improve exceptions
+            throw new LogicException('The node factory must return a movable node instance.');
+        }
+
+        $childrenData = $childrenExtractor($data, $node);
+        if (null !== $childrenData && !is_iterable($childrenData)) {
+            // TODO improve exceptions
+            throw new LogicException('Children data extractor must return an iterable collection containing children data.');
+        }
+        foreach ($childrenData ?? [] as $key => $childData) {
+            $child = $this->buildNode(
+                data: $childData,
+                nodeFactory: $nodeFactory,
+                childrenExtractor: $childrenExtractor,
+            );
+            $child->setParent($node);
+            $node->addChild($child, $key);
+        }
+        return $node;
+    }
+}