package cn.coyoteam.aweresf.web.servlet;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import cn.coyoteam.aweresf.consts.XWConst;
import cn.coyoteam.aweresf.util.StringHelper;
import cn.coyoteam.aweresf.web.xw.render.XWRenderAsJson;
import cn.coyoteam.aweresf.web.xw.render.XWRenderIntercept;

import com.amarsoft.awe.dw.ASObjectModel;
import com.amarsoft.awe.dw.ASObjectWindow;
	
/***
 * DW或OW重新定向渲染处理Servlet
 * @author EX-YANGSONG001
 * @date 2015/5/14
 */
public class XWRenderServlet extends HttpServlet {

    private static final long serialVersionUID = 1836559134168560992L;
    private Properties xwInterceptProperties = new Properties();
    
    public XWRenderServlet() {
        super();
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        ASObjectModel doTemp = (ASObjectModel)request.getAttribute("doTemp");
        ASObjectWindow dwTemp = (ASObjectWindow)request.getAttribute("dwTemp");
        @SuppressWarnings("unchecked")
        XWRenderAsJson<ASObjectModel,ASObjectWindow> owRender = (XWRenderAsJson<ASObjectModel,ASObjectWindow>)request.getAttribute("owRender");

        //对象不存在，则抛出错误
        if(doTemp == null || dwTemp == null) { 
            throw new ServletException("owRender not found!");
        }
        
        //如果相应的URI有拦截器存在，则设置拦截器，以备在数据渲染时调用
        String xwUri = (String)request.getAttribute(XWConst.XWURI);
        XWRenderIntercept xwRenderIntercept = lookupXWRenderIntercept(xwUri);
        if(xwRenderIntercept!=null)owRender.setXwRenderIntercept(xwRenderIntercept);
        //执行渲染
        owRender.initXw(doTemp, dwTemp);
        owRender.render(request, response);
    }
    
    protected XWRenderIntercept lookupXWRenderIntercept(String xwUri){
    	String className = xwInterceptProperties.getProperty(xwUri);
    	if(className==null)return null;
    	try {
			Object object = Class.forName(className).newInstance();
			if(object instanceof XWRenderIntercept){
				XWRenderIntercept renderIntercept = (XWRenderIntercept)object;
				return renderIntercept;
			}
		} catch (InstantiationException e) {
			throw new RuntimeException(e);
		} catch (IllegalAccessException e) {
			throw new RuntimeException(e);
		} catch (ClassNotFoundException e) {
			throw new RuntimeException(e);
		}
    	return null;
    }

	public void init(ServletConfig filterConfig) throws ServletException {
		super.init(filterConfig);
		String interceptConfig = StringHelper.nvl(filterConfig.getInitParameter(XWConst.KEY_XW_INTERCEPT_CONFIG),"");
		interceptConfig = interceptConfig.replaceAll("\\s+", "");
		
		if(interceptConfig!=null&&interceptConfig.startsWith("classpath:")){
			interceptConfig = interceptConfig.substring(10);
			InputStream in = getClass().getResourceAsStream(interceptConfig);
			try {
				xwInterceptProperties.load(in);
			} catch (IOException e) {
				throw new ServletException(String.format("load %s file error", XWConst.KEY_XW_INTERCEPT_CONFIG));
			}
		}
	}

    


}