<?php
/**
* Copyright © Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/
namespace Magento\Framework\Config\Converter\Dom;

use Magento\Framework\Config\Dom\ArrayNodeConfig;

/**
* Universal converter of any XML data to an array representation with no data loss
*
* @api
* @since 100.0.2
*/
class Flat
{
/**
* @var ArrayNodeConfig
*/
protected $arrayNodeConfig;

/**
* Constructor
*
* @param ArrayNodeConfig $arrayNodeConfig
*/
public function __construct(ArrayNodeConfig $arrayNodeConfig)
{
$this->arrayNodeConfig = $arrayNodeConfig;
}

/**
* Convert dom node tree to array in general case or to string in a case of a text node
*
* Example:
* <node attr="val">
* <subnode>val2<subnode>
* </node>
*
* is converted to
*
* array(
* 'node' => array(
* 'attr' => 'wal',
* 'subnode' => 'val2'
* )
* )
*
* @param \DOMNode $source
* @param string $basePath
* @return string|array
* @throws \UnexpectedValueException
* @SuppressWarnings(PHPMD.CyclomaticComplexity)
*/
public function convert(\DOMNode $source, $basePath = '')
{
$value = [];
/** @var \DOMNode $node */
foreach ($source->childNodes as $node) {
if ($node->nodeType == XML_ELEMENT_NODE) {
$nodeName = $node->nodeName;
$nodePath = $basePath . '/' . $nodeName;

$arrayKeyAttribute = $this->arrayNodeConfig->getAssocArrayKeyAttribute($nodePath);
$isNumericArrayNode = $this->arrayNodeConfig->isNumericArray($nodePath);
$isArrayNode = $isNumericArrayNode || $arrayKeyAttribute;

if (isset($value[$nodeName]) && !$isArrayNode) {
throw new \UnexpectedValueException(
"Node path '{$nodePath}' is not unique, but it has not been marked as array."
);
}

$nodeData = $this->convert($node, $nodePath);

if ($isArrayNode) {
if ($isNumericArrayNode) {
$value[$nodeName][] = $nodeData;
} elseif (isset($nodeData[$arrayKeyAttribute])) {
$arrayKeyValue = $nodeData[$arrayKeyAttribute];
$value[$nodeName][$arrayKeyValue] = $nodeData;
} else {
throw new \UnexpectedValueException(
"Array is expected to contain value for key '{$arrayKeyAttribute}'."
);
}
} else {
$value[$nodeName] = $nodeData;
}
} elseif ($node->nodeType == XML_CDATA_SECTION_NODE
|| ($node->nodeType == XML_TEXT_NODE && trim($node->nodeValue) != '')
) {
$value = $node->nodeValue;
break;
}
}
$result = $this->getNodeAttributes($source);
if (is_array($value)) {
$result = array_merge($result, $value);
if (!$result) {
$result = '';
}
} else {
if ($result) {
$result['value'] = trim($value);
} else {
$result = trim($value);
}
}
return $result;
}

/**
* Retrieve key-value pairs of node attributes
*
* @param \DOMNode $node
* @return array
*/
protected function getNodeAttributes(\DOMNode $node)
{
$result = [];
$attributes = $node->attributes ?: [];
/** @var \DOMNode $attribute */
foreach ($attributes as $attribute) {
if ($attribute->nodeType == XML_ATTRIBUTE_NODE) {
$result[$attribute->nodeName] = $attribute->nodeValue;
}
}
return $result;
}
}