package cn.ksource.web.controller.wechat.util;

import java.io.InputStream;
import java.io.Writer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

import cn.ksource.web.controller.wechat.response.RspTextMessage;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.core.util.QuickWriter;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;
import com.thoughtworks.xstream.io.xml.XppDriver;


/** 
 * 消息工具类 
 *  
 * @author jiangxiaolei 
 */ 
@SuppressWarnings("unchecked") 
public class MessageUtil {  
/** 
 * 返回消息类型：文本 
 */  
public static final String RESP_MESSAGE_TYPE_TEXT = "text";  

/** 
 * 请求消息类型：推送 event
 */  
public static final String REQ_MESSAGE_TYPE_EVENT = "event"; 






/** 
 * 解析微信发来的请求（XML） 
 *  
 * @param request 
 * @return 
 * @throws Exception 
 */  
 
public static Map<String, String> parseXml(HttpServletRequest request) throws Exception {  
    // 将解析结果存储在HashMap中  
    Map<String, String> map = new HashMap<String, String>();  

    // 从request中取得输入流  
    InputStream inputStream = request.getInputStream();
    
	// 读取输入流  
	SAXReader reader = new SAXReader();  
	Document document = reader.read(inputStream);
	
	System.out.println("微信用户向公众号发送的消息：");
	System.out.println(document.asXML());
	// 得到xml根元素  
	Element root = document.getRootElement();  
	// 得到根元素的所有子节点  
	List<Element> elementList = root.elements();  
	
	// 遍历所有子节点  
	for (Element e : elementList) {
		map.put(e.getName(), e.getText());  
	}

    // 释放资源  
    inputStream.close();  
    inputStream = null;  

    return map;  
}  

public static Map<String, String> parseStreamXml(InputStream xml) throws Exception {  
    // 将解析结果存储在HashMap中  
    Map<String, String> map = new HashMap<String, String>();  
    // 读取输入流  
    SAXReader reader = new SAXReader();  
    Document document = reader.read(xml);  
    // 得到xml根元素  
    Element root = document.getRootElement();  
    // 得到根元素的所有子节点  
    List<Element> elementList = root.elements();  

 // 遍历所有子节点  
    for (Element e : elementList) {
    	map.put(e.getName(), e.getText());  
    }

    return map;  
}  

/** 
 * 文本消息对象转换成xml 
 *  
 * @param textMessage 文本消息对象 
 * @return xml 
 */  
public static String textMessageToXml(RspTextMessage textMessage) {
    xstream.alias("xml", textMessage.getClass());  
    return xstream.toXML(textMessage);  
}  



	/** 
	 * 扩展xstream，使其支持CDATA块 
	 *  
	 * @date 2013-05-19 
	 */  
	private static XStream xstream = new XStream(new XppDriver() {  
	    public HierarchicalStreamWriter createWriter(Writer out) {  
	        return new PrettyPrintWriter(out) {  
	            // 对所有xml节点的转换都增加CDATA标记  
	            boolean cdata = true;  
	
	            @SuppressWarnings("unchecked")  
	            public void startNode(String name, Class clazz) {  
	                super.startNode(name, clazz);  
	            }  
	
	            protected void writeText(QuickWriter writer, String text) {  
	                if (cdata) {  
	                    writer.write("<![CDATA[");  
	                    writer.write(text);  
	                    writer.write("]]>");  
	                } else {  
	                    writer.write(text);  
	                }  
	            }  
	        };  
	    }  
	});
	
}