/**
 * Copyright 2019 Huawei Technologies Co.,Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
 * this file except in compliance with the License.  You may obtain a copy of the
 * License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed
 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
 * CONDITIONS OF ANY KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations under the License.
 *
 */

function Xml2Json() {
	let json2Str = function(jsonObj) {
		let rejsn = JSON.stringify(jsonObj, undefined, 2).replace(
				/(\\t|\\r|\\n)/g, '').replace(/"",[\n\t\r\s]+""[,]*/g, '')
				.replace(/(\n[\t\s\r]*\n)/g, '').replace(
						/[\s\t]{2,}""[,]{0,1}/g, '').replace(
						/"[\s\t]{1,}"[,]{0,1}/g, '');
		return (rejsn.indexOf('"parsererror": {') === -1) ? rejsn : 'Invalid XML format';
	};
	
	
	let setJsonObj = function(xmlDoc) {
		let jsonObj = {};
		if (xmlDoc.nodeType === 1) {
			if (xmlDoc.attributes.length > 0) {
				jsonObj['@attributes'] = {};
				for (let j = 0; j < xmlDoc.attributes.length; j++) {
					let attribute = xmlDoc.attributes.item(j);
					jsonObj['@attributes'][attribute.nodeName] = attribute.value;
				}
			}
		} else if (xmlDoc.nodeType === 3) {
			jsonObj = xmlDoc.nodeValue;
		}
		if (xmlDoc.hasChildNodes()) {
			for (let i = 0; i < xmlDoc.childNodes.length; i++) {
				let item = xmlDoc.childNodes.item(i);
				let nodeName = item.nodeName;
				if (jsonObj[nodeName] === undefined) {
					jsonObj[nodeName] = setJsonObj(item);
				} else {
					if (jsonObj[nodeName].push === undefined) {
						let old = jsonObj[nodeName];
						jsonObj[nodeName] = [];
						jsonObj[nodeName].push(old);
					}
					jsonObj[nodeName].push(setJsonObj(item));
				}
			}
		}
		return jsonObj;
	};
	
	let self = this;
	self.parseString = function(xml, rstr) {
		let xmlDoc;
		if (window.DOMParser) {
			xmlDoc = new window.DOMParser().parseFromString(xml, 'text/xml');
		} else {
			xmlDoc = new window.ActiveXObject('Microsoft.XMLDOM');
			xmlDoc.async = 'false';
		}
		let ret = json2Str(setJsonObj(xmlDoc));
		return (rstr === undefined) ? JSON.parse(ret) : ret;
	};
}

export default new Xml2Json();