#45 Add rootline and rootline item class

src/StackFormation/PreProcessor/Rootline.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace StackFormation\PreProcessor;
+
+/**
+ * Class Rootline
+ *
+ * The rootline shows gives the transformers access to the parent objects (all generations)
+ * since sometimes you need to change things outside of the current value (e.g. when replacing the whole node)
+ */
+class Rootline extends \ArrayObject {
+
+    /**
+     * @return array
+     */
+    protected function getKeys() {
+        return array_keys($this->getArrayCopy());
+    }
+
+    /**
+     * @param $index
+     * @return mixed
+     */
+    public function indexGet($index) {
+        $keys = $this->getKeys();
+        return $this->offsetGet($keys[$index]);
+    }
+
+    public function removeLast() {
+        $keys = $this->getKeys();
+
+        // TODO
+        @$this->offsetUnset($keys[$this->count()]);
+    }
+
+    /**
+     * @param int $generation
+     * @return mixed
+     */
+    public function parent($generation = 1) {
+        $keys = $this->getKeys();
+        return $this->offsetGet($keys[$this->count() - $generation]);
+    }
+}

src/StackFormation/PreProcessor/RootlineItem.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace StackFormation\PreProcessor;
+
+/**
+ * Class RootlineItem
+ *
+ * Since you not only need the reference to the parent(s) but also their key in relation to their parent
+ * (e.g. in case you need to delete them), this rootline item represents the item itself (value) and the position (key)
+ */
+class RootlineItem {
+
+    protected $key;
+    protected $value;
+
+    /**
+     * @param string $key
+     * @param mixed $value
+     */
+    public function __construct($key, $value) {
+        $this->key = $key;
+        $this->value = $value;
+    }
+
+    /**
+     * @return string
+     */
+    public function getKey() {
+        return $this->key;
+    }
+
+    /**
+     * @return mixed
+     */
+    public function getValue() {
+        return $this->value;
+    }
+}