package com.filter;

import java.io.IOException;
import java.sql.SQLException;
import java.util.Date;

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

import com.dao.VoterDao;
import com.toolsbean.StringHandler;

public class VoteLimitFilter implements Filter {
	private FilterConfig fc=null;

	public void doFilter(ServletRequest srequest, ServletResponse sresponse,FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request=(HttpServletRequest)srequest;
		HttpServletResponse response=(HttpServletResponse)sresponse;
		HttpSession session=request.getSession();
		
		//查询服务器端该IP上次投票的时间
		String ip=request.getRemoteAddr();										//获取客户端IP
		long ipnum=StringHandler.getIpNum(ip);
		int optionid=Integer.parseInt(request.getParameter("movie"));			//获取选择的选项ID
		try {				
			VoterDao voterDao=new VoterDao();
			Date now=new Date();												//获取当前时间
			Date last = voterDao.getLastVoteTime(ipnum);							//获取该IP的上次投票时间
			
			if(last==null){														//数据库中没有记录该IP，则该IP地址没有投过票
				addCookie(request,response);											//在客户端的cookie中记录该用户已经投过票
				
				Object[] params={ipnum,optionid,StringHandler.timeTostr(now)};
				voterDao.saveVoteTime(params);											//在数据库中记录该IP、选择的选项ID和投票时间
				chain.doFilter(request,response);
			}
			else{																//该IP地址投过票，则接着判断客户端cookie中是否记录了用户投票情况（用来解决局域网中某个ip投票后，其他ip不能再进行投票的问题）
				boolean voteincookie=seeCookie(request);								//判断当前使用该IP的用户的客户端的cookie中是否记录了投票标记
				if(voteincookie){														//如果记录了该用户已经投过票
					request.setAttribute("message","● 您已经投过票了，1小时内不允许重复投票！");
					RequestDispatcher rd=request.getRequestDispatcher("fail.jsp");
					rd.forward(request,response);
				}
				else{																	//没有记录该用户是否投过票，则接着判断当前session中是否记录了用户投票的情况（用来解决用户投票后，删除本地cookie实现重复投票）
					String ido=(String)session.getAttribute("ido");
					if("yes".equals(ido)){														//当前用户已投过票
						request.setAttribute("message","● 您已经投过票了，1小时内不允许重复投票！");
						RequestDispatcher rd=request.getRequestDispatcher("fail.jsp");
						rd.forward(request,response);
					}
					else{
						addCookie(request,response);											//在客户端的cookie中记录该用户已经投过票
						
						Object[] params={ipnum,optionid,StringHandler.timeTostr(now)};
						voterDao.saveVoteTime(params);											//记录使用该IP的用户的投票时间
						chain.doFilter(request,response);
					}
				}
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}		
	}
	private boolean seeCookie(HttpServletRequest request){
		boolean hasvote=false;
		String webName=request.getContextPath();
		webName=webName.substring(1);
		String cookiename=webName+".voter";
		
		Cookie[] cookies=request.getCookies();
		if(cookies!=null&&cookies.length!=0){
			for(int i=0;i<cookies.length;i++){
				Cookie single=cookies[i];
				if(single.getName().equals(cookiename)&&single.getValue().equals("I Have Vote")){
					hasvote=true;
					break;
				}					
			}
		}		
		return hasvote;		
	}
	private void addCookie(HttpServletRequest request,HttpServletResponse response){
		String webname=request.getContextPath();
		webname=webname.substring(1);
		Cookie cookie=new Cookie(webname+".voter","I Have Vote");		//创建一个cookie
		cookie.setPath("/");
		cookie.setMaxAge(60*60*1);										//设置cookie在客户端保存的有效时间为1小时	
		response.addCookie(cookie);										//向客户端写入cookie
	}
	public void init(FilterConfig fc) throws ServletException {
		this.fc=fc;
	}
	public void destroy() {
		this.fc=null;
	}
}