<?php
/**
 * XML handling for Cake.
 *
 * The methods in these classes enable the datasources that use XML to work.
 *
 * PHP 5
 *
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @package       cake
 * @subpackage    cake.cake.libs
 * @since         CakePHP v .0.10.3.1400
 * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 */

class Xml {

/**
 * Initialize SimpleXMLElement from a given XML string, file path, URL or array.
 *
 * @param mixed $input XML string, a path to a file, an URL or an array
 * @return object SimpleXMLElement
 */
	public static function build($input) {
		if (is_array($input) || is_object($input)) {
			return self::fromArray((array)$input);
		} elseif (strstr($input, "<")) {
			return new SimpleXMLElement($input);
		} elseif (file_exists($input) || strpos($input, 'http://') === 0 || strpos($input, 'https://') === 0 ) {
			return new SimpleXMLElement($input, null, true);
		} elseif (!is_string($input)) {
			throw new Exception(__('Invalid input.'));
		}
		throw new Exception(__('XML cannot be read.'));
	}

/**
 * Transform an array in a SimpleXMLElement
 *
 * @param array $input Array with data
 * @param string $format If create childs ('tags') or attributes ('attribute')
 * @return object SimpleXMLElement
 */
	public static function fromArray($input, $format = 'attribute') {
		if (!is_array($input) || count($input) !== 1) {
			throw new Exception(__('Invalid input.'));
		}
		$key = key($input);
		if (is_integer($key)) {
			throw new Exception(__('The key of input must be alphanumeric'));
		}
		if (is_array($input[$key])) {
			$simpleXml = new SimpleXMLElement('<' . '?xml version="1.0"?' . '><' . $key . ' />');
			self::_fromArrayRecursive($simpleXml, $input[$key], $format);
		} else {
			$simpleXml = new SimpleXMLElement('<' . '?xml version="1.0"?' . '><' . $key . '>' . $input[$key] . '</' . $key . '>');
		}
		return $simpleXml;
	}

/**
 * Recursive method to create SimpleXMLElement from array
 *
 * @param object $node Handler to SimpleXMLElement
 * @param array $array
 * @param string $format
 * @return void
 */
	protected static function _fromArrayRecursive(&$node, &$array, $format = 'attribute') {
		if (empty($array) || !is_array($array)) {
			return;
		}
		foreach ($array as $key => $value) {
			if (is_string($key)) {
				if (!is_array($value)) {
					if (is_bool($value)) {
						$value = (int)$value;
					} elseif ($value === null) {
						$value = '';
					}
					if ($format === 'tags') {
						$node->addChild($key, $value);
					} else {
						$node->addAttribute($key, $value);
					}
				} else {
					if (array_keys($value) === range(0, count($value) - 1)) { // List
						foreach ($value as $item) {
							$child = $node->addChild($key);
							self::_fromArrayRecursive($child, $item, $format);
						}
					} else { // Struct
						$child = $node->addChild($key);
						self::_fromArrayRecursive($child, $value, $format);
					}
				}
			} else {
				throw new Exception(__('Invalid array'));
			}
		}
	}

/**
 * Returns this XML structure as a array.
 *
 * @param object $simpleXML SimpleXMLElement instance
 * @return array Array representation of the XML structure.
 */
	public static function toArray($simpleXML) {
		if (!($simpleXML instanceof SimpleXMLElement)) {
			throw new Exception(__('The input is not instance of SimpleXMLElement.'));
		}
		$result = array();
		self::_toArray($simpleXML, $result);
		return $result;
	}

/**
 * Recursive method to toArray
 *
 * @param object $xml SimpleXMLElement object
 * @param array $parentData Parent array with data
 * @return void
 */
	protected static function _toArray($xml, &$parentData) {
		$data = array();

		foreach ($xml->attributes() as $key => $value) {
			$data[$key] = (string)$value;
		}

		foreach ($xml->children() as $child) {
			self::_toArray($child, $data);
		}

		if (empty($data)) {
			$data = (string)$xml;
		}

		$name = $xml->getName();
		if (isset($parentData[$name])) {
			if (!is_array($parentData[$name]) || !isset($parentData[$name][0])) {
				$parentData[$name] = array($parentData[$name]);
			}
			$parentData[$name][] = $data;
		} else {
			$parentData[$name] = $data;
		}
	}

}