Add support for customizing Menus and Menu Items

Author: stevep

.gitignore

@@ -1,4 +1,7 @@
 vendor
 composer.lock
 .DS_Store
-.idea
+.idea
+tests/_output
+tests/wp
+wp-content

lib/Config/MenuItem.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace Understory;
+
+use Timber;
+
+class MenuItem extends Timber\MenuItem implements MetaDataBinding
+{
+    public function getBindingName()
+    {
+        return $this->post_type;
+    }
+
+    /**
+     * Implentation of MetaDataBinding::getMetaValue
+     *
+     * @param  string $key Key for the meta field
+     * @return string Value of the meta field
+     */
+    public function getMetaValue($key)
+    {
+        return \get_post_meta($this->ID, $key, true);
+    }
+
+    /**
+     * Implentation of MetaDataBinding::setMetaValue
+     *
+     * @param  string $key Key for the meta field
+     * @param  string $value Value for the meta field
+     */
+    public function setMetaValue($key, $value)
+    {
+        \update_post_meta($this->ID, $key, $value);
+    }
+
+    /**
+     * Order of method calls:
+     *
+     * 1. getMethodName($args)
+     * 2. methodName($args)
+     * 3. propertyName
+     * 4. fall back to Timber's core implementation
+     *
+     * @param string $propertyName
+     * @param array $args
+     * @return mixed
+     */
+    public function __call($propertyName, $args = [])
+    {
+        if (method_exists($this, 'get'.$propertyName)) {
+            return call_user_func_array([$this, 'get'.$propertyName], $args);
+        } else if (method_exists($this, $propertyName)) {
+            return call_user_func_array([$this, $propertyName], $args);
+        } else if (property_exists($this, $propertyName)) {
+            return $this->$propertyName;
+        }
+
+        return parent::__call($propertyName, $args);
+    }
+}

lib/CustomNavMenuItem.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Understory;
+
+abstract class CustomNavMenuItem extends CustomPostType
+{
+    static public $name = 'nav_menu_item';
+
+    public function setPost($post = null)
+    {
+        $this->setMetaDataBinding(new MenuItem($post));
+        $this->getConfig();
+    }
+}

lib/Menu.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Understory;
+
+use Timber;
+
+class Menu extends Timber\Menu
+{
+    public $MenuItemClass = MenuItem::class;
+}