package com.test.util;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.test.bean.Student;

/**
 * 權限驗證
 * 
 * @author javabs
 * 
 */
public class CheckFilter implements Filter {

	public void destroy() {

	}

	public void doFilter(ServletRequest req, ServletResponse res,
			FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest) req;
		HttpServletResponse response = (HttpServletResponse) res;
		Student stu = (Student) request.getSession().getAttribute("stu");
		String path = request.getRequestURI();
		// 不是登陸頁,且沒有登陸
		if (!path.substring(path.lastIndexOf("/") + 1).equals("index.jsp")
				&& stu == null) {
			String cmd = request.getQueryString();
			if (cmd == null) {
				response.sendRedirect("index.jsp");
			} else if (cmd != null && !cmd.equals("cmd=login")
					&& !cmd.equals("cmd=checkCode")) {
				response.sendRedirect("index.jsp");
			} else {
				chain.doFilter(request, response);
			}

		} else {
			chain.doFilter(request, response);
		}
	}

	public void init(FilterConfig arg0) throws ServletException {

	}

}