<?php
namespace Org\Helper;

use Think\Exception;

/**
 * XML2Array: A class to convert XML to array in PHP
 * It returns the array which can be converted back to XML using the Array2XML script
 * It takes an XML string or a DOMDocument object as an input.
 *
 * See Array2XML: http://www.lalit.org/lab/convert-php-array-to-xml-with-attributes
 *
 * Author : Lalit Patel
 * Website: http://www.lalit.org/lab/convert-xml-to-array-in-php-xml2array
 * License: Apache License 2.0
 *          http://www.apache.org/licenses/LICENSE-2.0
 * Version: 0.1 (07 Dec 2011)
 * Version: 0.2 (04 Mar 2012)
 * 			Fixed typo 'DomDocument' to 'DOMDocument'
 *
 * Usage:
 *       $array = XML2Array::createArray($xml);
 */

class XML2Array {

	private static $xml = null;
	private static $encoding = 'UTF-8';

	/**
	 * Initialize the root XML node [optional]
	 * @param $version
	 * @param $encoding
	 * @param $format_output
	 */
	public static function init($version = '1.0', $encoding = 'UTF-8', $format_output = true) {
		self::$xml = new \DOMDocument($version, $encoding);
		self::$xml->formatOutput = $format_output;
		self::$encoding = $encoding;
	}

	/**
	 * Convert an XML to Array
	 * @param string $node_name - name of the root node to be converted
	 * @param array $arr - aray to be converterd
	 * @return DOMDocument
	 */
	public static function &createArray($input_xml) {
		$xml = self::getXMLRoot();
		if(is_string($input_xml)) {
			$parsed = $xml->loadXML($input_xml);
			if(!$parsed) {
				throw new Exception('[XML2Array] Error parsing the XML string.');
			}
		} else {
			if(get_class($input_xml) != 'DOMDocument') {
				throw new Exception('[XML2Array] The input XML object should be of type: DOMDocument.');
			}
			$xml = self::$xml = $input_xml;
		}
		$array[$xml->documentElement->tagName] = self::convert($xml->documentElement);
		self::$xml = null;    // clear the xml node in the class for 2nd time use.
		return $array;
	}

	/**
	 * Convert an Array to XML
	 * @param mixed $node - XML as a string or as an object of DOMDocument
	 * @return mixed
	 */
	private static function &convert($node) {
		$output = [];

		switch ($node->nodeType) {
			case XML_CDATA_SECTION_NODE:
				$output['@cdata'] = trim($node->textContent);
				break;

			case XML_TEXT_NODE:
				$output = trim($node->textContent);
				break;

			case XML_ELEMENT_NODE:

				// for each child node, call the covert function recursively
				for ($i=0, $m=$node->childNodes->length; $i<$m; $i++) {
					$child = $node->childNodes->item($i);
					$v = self::convert($child);
					if(isset($child->tagName)) {
						$t = $child->tagName;

						// assume more nodes of same kind are coming
						if(!isset($output[$t])) {
							$output[$t] = [];
						}
						$output[$t][] = $v;
					} else {
						//check if it is not an empty text node
						if($v !== '') {
							$output = $v;
						}
					}
				}

				if(is_array($output)) {
					// if only one node of its kind, assign it directly instead if array($value);
					foreach ($output as $t => $v) {
						if(is_array($v) && count($v)==1) {
							$output[$t] = $v[0];
						}
					}
					if(empty($output)) {
						//for empty nodes
						$output = '';
					}
				}

				// loop through the attributes and collect them
				if($node->attributes->length) {
					$a = [];
					foreach($node->attributes as $attrName => $attrNode) {
						$a[$attrName] = (string) $attrNode->value;
					}
					// if its an leaf node, store the value in @value instead of directly storing it.
					if(!is_array($output)) {
						$output = ['@value' => $output];
					}
					$output['@attributes'] = $a;
				}
				break;
		}
		return $output;
	}

	/*
	 * Get the root XML node, if there isn't one, create it.
	 */
	private static function getXMLRoot(){
		if(empty(self::$xml)) {
			self::init();
		}
		return self::$xml;
	}
}
?>