/*
 * @(#)RoleDAO.java        2005/10/18
 *
 * Copyright (c) 2003-2005 ASPire Technologies, Inc.
 * 6/F,IER BUILDING, SOUTH AREA,SHENZHEN HI-TECH INDUSTRIAL PARK Mail Box:11# 12#.
 * All rights reserved.
 */
package org.appfuse.webapp.filter;

import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

import org.apache.commons.logging.*;
import org.appfuse.util.security.*;
import org.appfuse.util.*;
import org.jdom.*;
import org.jdom.input.*;
import org.appfuse.service.StaffManager;
import org.appfuse.model.Staff;

/**
 * <p>Title: securityservice</p>
 * @author maoqian
 * @version 1.0
 */
public class AuthFilter extends HttpServlet implements Filter{
    private FilterConfig filterConfig;
    private static Log log = LogFactory.getLog(AuthFilter.class);
    public static ArrayList unProtectedRes = null;
    private static Element rootElement = null;

    public AuthFilter() {
    }

    public void init(FilterConfig filtercfg) throws javax.servlet.
        ServletException {
        getUnprotectedResources();
    }

    public void doFilter(ServletRequest request, ServletResponse response,
                         FilterChain filterchain) throws java.io.IOException,
        javax.servlet.ServletException {
        try {
            HttpServletRequest req = (HttpServletRequest)request;
            HttpServletResponse resp = (HttpServletResponse)response;
            String tempURL = req.getRequestURI();
//            log.debug("getRequestURI: " + tempURL);
//            log.debug("getRequestURL: " + req.getRequestURL().toString());
            log.debug("getRequestURL + queryString: " + req.getRequestURL().toString() + "?" + req.getQueryString());
            boolean isUnprotected = isUnprotectedUrl(req);
            if(isUnprotected){
                filterchain.doFilter(request, response);
                return;
            }

            if(req.getSession().getAttribute("staff") == null){
                resp.sendRedirect("login.jsp");
                return;
            }

            Staff staff = (Staff)req.getSession().getAttribute("staff");
            if(checkSafe(req, staff)){
                filterchain.doFilter(request, response);
                return;
            } else {
                resp.sendRedirect("checkfail.jsp");
            }

        } catch(Exception e) {
            log.error("error in authorization filter", e);
        }
    }

    private boolean isUnprotectedUrl(HttpServletRequest request) {
        String url = request.getRequestURI().toString();
        int index = url.lastIndexOf("/");
        if(index > -1){
            url = url.substring(index + 1);
        }
        for(int i = 0; i < unProtectedRes.size(); i++){
            String temp = (String)unProtectedRes.get(i);
            if(url.lastIndexOf(temp) > -1)
                return true;
        }
        if(url.endsWith(".do")){
            url = url + "?" +  request.getQueryString();
            for(int i = 0; i < unProtectedRes.size(); i++){
                String temp = (String)unProtectedRes.get(i);
                if(url.indexOf(temp) > -1)
                    return true;
            }
        }
        return false;
    }

    private boolean checkSafe(HttpServletRequest request, Staff staff) {
        String url = request.getRequestURI();
        String action =  request.getParameter("method");
        int index = url.lastIndexOf("/");
        if(index > -1){
            url = url.substring(index + 1);
        }
        if(url.endsWith(".do")){
            if(action == null) {
                action ="list";
            }
            try {
                log.debug("checkSafe: " + url + "|"+ action);
                return staff.checkSafe(url, action);
            }catch(Exception es){
                log.error(es);
            }
        } else {
            return true;//對于那些需要打開才能進行的操作，主要是：創建、編輯這類頁面
        }
        return false;
    }


    public void destroy() {
    }

    /**
     * 載入配置文件
     * @param cfg 配置文件名稱
     */
    public static void load(String cfg) {
        try {
            rootElement = new SAXBuilder().build(new File(cfg)).getRootElement();
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 獲得配置文件中指定名稱的Element
     * @param elementName
     * @return
     */
    public static Element getElement(String elementName) {
        return rootElement.getChild(elementName);
    }

    /**
     * 獲取不受訪問限制的資源信息列表，調用之前需要先執行load()方法；
     */
    public static void getUnprotectedResources() {

        if(unProtectedRes == null) {
            unProtectedRes = new ArrayList();
            List urlList = new ArrayList();
            Element interceptors = getElement("unprotectedurls");
            urlList = interceptors.getChildren("unprotectedurl");
            Iterator it = urlList.iterator();
            Element tmpElement = null;
            while(it.hasNext()) {
                tmpElement = (Element)it.next();
                unProtectedRes.add(tmpElement.getAttributeValue("url"));
            }
        }
    }

    public static void main(String[] args) {

        AuthFilter tools = new AuthFilter();
        tools.load("config/unprotectedurl.xml");
        tools.getUnprotectedResources();
        //System.out.println(unProtectedRes.toString());

    }

}