package com.oozero.nmshop.system.filter;

import java.io.IOException;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.web.filter.OncePerRequestFilter;

import com.oozero.nmshop.system.pojo.Employee;
import com.oozero.nmshop.system.util.JNConstant;


public class LoginSessionFilter extends OncePerRequestFilter {

    private static final String[] ignores = new String[] { "/login.jsp", "resources", "base/user/login", "menu/init",
            "/system/loginStatistics/addString", "mutilUpload" };

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
            throws ServletException, IOException {

        request = new Request((HttpServletRequest) request);

        response.setHeader("Set-Cookie", "name=value; HttpOnly");

        String referer = request.getHeader("Referer"); // REFRESH
        if (referer != null && referer.indexOf(request.getContextPath()) < 0) {

            HttpServletResponse servletResponse = (HttpServletResponse) response;
            HttpServletRequest servletRequest = (HttpServletRequest) request;

            servletResponse.sendRedirect(servletRequest.getContextPath() + "/error.jsp");

        } else {

            // 获得在下面代码中要用的request,response,session对象
            HttpServletRequest servletRequest = (HttpServletRequest) request;
            HttpServletResponse servletResponse = (HttpServletResponse) response;
            HttpSession session = servletRequest.getSession();

            Employee employee = (Employee) session.getAttribute(JNConstant.LOGIN_SESSION);

            String path = servletRequest.getRequestURI();

            if (employee != null) {
                chain.doFilter(servletRequest, servletResponse);
                return;
            }

            // 登陆页面无需过滤
            for (String s : ignores) {
                if (path.indexOf(s) > -1) {
                    chain.doFilter(servletRequest, servletResponse);
                    return;
                }
            }
            // 判断如果没有取到员工信息,就跳转到登陆页面

            if (employee == null && (path.indexOf("admin") > -1 || path.indexOf("system") > -1)) {
                
                String queryString="";
                if(request.getQueryString()!=null){
                    queryString="?"+request.getQueryString();
                }
                
                // 跳转到登陆页面
                servletResponse.sendRedirect(servletRequest.getContextPath() + "/login.jsp?url=http://"
                        + servletRequest.getHeader("host") + path + queryString);
            } else {
                // 已经登陆,继续此次请求
                chain.doFilter(request, response);
            }

        }

    }

    public String filterDangerString(String value) {
        if (value == null) {
            return null;
        }
        value = value.replaceAll("\\|", "");

        value = value.replaceAll("&", "&");

        value = value.replaceAll(";", "");

        value = value.replaceAll("@", "");

        value = value.replaceAll("'", "");

        value = value.replaceAll(""", "");

        value = value.replaceAll("\\'", "");

        value = value.replaceAll("\\"", "");

        value = value.replaceAll("<", "<");

        value = value.replaceAll(">", ">");

        value = value.replaceAll("\\(", "");

        value = value.replaceAll("\\)", "");

        value = value.replaceAll("\\+", "");

        value = value.replaceAll("\r", "");

        value = value.replaceAll("\n", "");

        value = value.replaceAll("script", "");

        value = value.replaceAll("'", "");
        value = value.replaceAll(""", "");
        value = value.replaceAll(">", "");
        value = value.replaceAll("<", "");
        value = value.replaceAll("=", "");
        value = value.replaceAll("/", "");
        return value;
    }

    class Request extends HttpServletRequestWrapper {
        public Request(HttpServletRequest request) {
            super(request);
        }

        @Override
        public String getParameter(String name) {
            // 返回值之前 先进行过滤
            return filterDangerString(super.getParameter(name));
        }

        @Override
        public String[] getParameterValues(String name) {
            // 返回值之前 先进行过滤
            String[] values = super.getParameterValues(name);
            for (int i = 0; i < values.length; i++) {
                values[i] = filterDangerString(values[i]);
            }
            return values;
        }
    }

}