/**
   * 引入 Security 配置屬性類
   */
  @Autowired
  private SecurityProperties securityProperties;


  @Override
  public ImageCode createCode(HttpServletRequest request ) {
    //如果請求中有 width 參數，則用請求中的，否則用 配置屬性中的
    int width = ServletRequestUtils.getIntParameter(request,"width",securityProperties.getWidth());
    //高度（寬度）
    int height = ServletRequestUtils.getIntParameter(request,"height",securityProperties.getHeight());
    //圖片驗證碼字符個數
    int length = securityProperties.getLength();
    //過期時間
    int expireIn = securityProperties.getExpireIn();

    BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

    Graphics g = image.getGraphics();

    Random random = new Random();

    g.setColor(getRandColor(200, 250));
    g.fillRect(0, 0, width, height);
    g.setFont(new Font("Times New Roman", Font.ITALIC, 20));
    g.setColor(getRandColor(160, 200));
    for (int i = 0; i < 155; i++) {
      int x = random.nextInt(width);
      int y = random.nextInt(height);
      int xl = random.nextInt(12);
      int yl = random.nextInt(12);
      g.drawLine(x, y, x + xl, y + yl);
    }

    String sRand = "";
    for (int i = 0; i < length; i++) {
      String rand = String.valueOf(random.nextInt(10));
      sRand += rand;
      g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
      g.drawString(rand, 13 * i + 6, 16);
    }

    g.dispose();

    return new ImageCode(image, sRand, expireIn);
  }

  /**
   * 生成隨機背景條紋
   */
  private Color getRandColor(int fc, int bc) {
    Random random = new Random();
    if (fc > 255) {
      fc = 255;
    }
    if (bc > 255) {
      bc = 255;
    }
    int r = fc + random.nextInt(bc - fc);
    int g = fc + random.nextInt(bc - fc);
    int b = fc + random.nextInt(bc - fc);
    return new Color(r, g, b);
  }

public static final String SESSION_KEY = "SESSION_KEY_IMAGE_CODE";

  @Autowired
  private ValidateCodeGenerator imageCodeGenerator;

  /**
   * Session 對象
   */
  private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();

  @GetMapping("/code/image")
  public void createCode(HttpServletRequest request, HttpServletResponse response) throws IOException {
    ImageCode imageCode = imageCodeGenerator.createCode(request);
    //將隨機數 放到Session中
    sessionStrategy.setAttribute(new ServletWebRequest(request),SESSION_KEY,imageCode);
    request.getSession().setAttribute(SESSION_KEY,imageCode);
    //寫給response 響應
    response.setHeader("Cache-Control", "no-store, no-cache");
    response.setContentType("image/jpeg");
    ImageIO.write(imageCode.getImage(),"JPEG",response.getOutputStream());
  }

@Data
public class ImageCode {

  /**
   * 圖片
   */
  private BufferedImage image;
  /**
   * 隨機數
   */
  private String code;
  /**
   * 過期時間
   */
  private LocalDateTime expireTime;

  public ImageCode(BufferedImage image, String code, LocalDateTime expireTime) {
    this.image = image;
    this.code = code;
    this.expireTime = expireTime;
  }
  public ImageCode(BufferedImage image, String code, int expireIn) {
    this.image = image;
    this.code = code;
    //當前時間 加上 設置過期的時間
    this.expireTime = LocalDateTime.now().plusSeconds(expireIn);
  }

  public boolean isExpried(){
    //如果 過期時間 在 當前日期 之前，則驗證碼過期
    return LocalDateTime.now().isAfter(expireTime);
  }
}

@ConfigurationProperties(prefix = "sso.security.code.image")
@Component
@Data
public class SecurityProperties {

  /**
   * 驗證碼寬度
   */
  private int width = 67;
  /**
   * 高度
   */
  private int height = 23;
  /**
   * 長度（幾個數字）
   */
  private int length = 4;
  /**
   * 過期時間
   */
  private int expireIn = 60;

  /**
   * 需要圖形驗證碼的 url
   */
  private String url;
}

@Component
@Slf4j
public class ValidateCodeFilter extends OncePerRequestFilter implements InitializingBean {

  /**
   * 登錄失敗處理器
   */
  @Autowired
  private AuthenticationFailureHandler failureHandler;
  /**
   * Session 對象
   */
  private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();

  /**
   * 創建一個Set 集合 存放 需要驗證碼的 urls
   */
  private Set<String> urls = new HashSet<>();
  /**
   * spring的一個工具類：用來判斷 兩字符串 是否匹配
   */
  private AntPathMatcher pathMatcher = new AntPathMatcher();

  @Autowired
  private SecurityProperties securityProperties;
  /**
   * 這個方法是 InitializingBean 接口下的一個方法， 在初始化配置完成后 運行此方法
   */
  @Override
  public void afterPropertiesSet() throws ServletException {
    super.afterPropertiesSet();
    //將 application 配置中的 url 屬性進行 切割
    String[] configUrls = StringUtils.splitByWholeSeparatorPreserveAllTokens(securityProperties.getUrl(), ",");
    //添加到 Set 集合里
    urls.addAll(Arrays.asList(configUrls));
    //因為登錄請求一定要有驗證碼 ，所以直接 add 到set 集合中
    urls.add("/authentication/form");
  }

  @Override
  protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException {

    boolean action = false;
    for (String url:urls){
      //如果請求的url 和 配置中的url 相匹配
      if (pathMatcher.match(url,httpServletRequest.getRequestURI())){
        action = true;
      }
    }

    //攔截請求
    if (action){
      logger.info("攔截成功"+httpServletRequest.getRequestURI());
      //如果是登錄請求
      try {
        validate(new ServletWebRequest(httpServletRequest));
      }catch (ValidateCodeException exception){
        //返回錯誤信息給 失敗處理器
        failureHandler.onAuthenticationFailure(httpServletRequest,httpServletResponse,exception);
        return;
      }

    }
    filterChain.doFilter(httpServletRequest,httpServletResponse);

  }
  private void validate(ServletWebRequest request) throws ServletRequestBindingException {
    //從session中取出 驗證碼
    ImageCode codeInSession = (ImageCode) sessionStrategy.getAttribute(request,ValidateCodeController.SESSION_KEY);
    //從request 請求中 取出 驗證碼
    String codeInRequest = ServletRequestUtils.getStringParameter(request.getRequest(),"imageCode");

    if (StringUtils.isBlank(codeInRequest)){
      logger.info("驗證碼不能為空");
      throw new ValidateCodeException("驗證碼不能為空");
    }
    if (codeInSession == null){
      logger.info("驗證碼不存在");
      throw new ValidateCodeException("驗證碼不存在");
    }
    if (codeInSession.isExpried()){
      logger.info("驗證碼已過期");
      sessionStrategy.removeAttribute(request,ValidateCodeController.SESSION_KEY);
      throw new ValidateCodeException("驗證碼已過期");
    }
    if (!StringUtils.equals(codeInSession.getCode(),codeInRequest)){
      logger.info("驗證碼不匹配"+"codeInSession:"+codeInSession.getCode() +", codeInRequest:"+codeInRequest);
      throw new ValidateCodeException("驗證碼不匹配");
    }
    //把對應 的 session信息 刪掉
    sessionStrategy.removeAttribute(request,ValidateCodeController.SESSION_KEY);
  }

@Autowired
  private ValidateCodeFilter validateCodeFilter;

  @Override
  protected void configure(HttpSecurity http) throws Exception {
    //在UsernamePasswordAuthenticationFilter 過濾器前 加一個過濾器 來搞驗證碼
    http.addFilterBefore(validateCodeFilter, UsernamePasswordAuthenticationFilter.class)
        //表單登錄 方式
        .formLogin()
        .loginPage("/authentication/require")
        //登錄需要經過的url請求
        .loginProcessingUrl("/authentication/form")
        .passwordParameter("pwd")
        .usernameParameter("user")
        .successHandler(mySuccessHandler)
        .failureHandler(myFailHandler)
        .and()
        //請求授權
        .authorizeRequests()
        //不需要權限認證的url
        .antMatchers("/authentication/*","/code/image").permitAll()
        //任何請求
        .anyRequest()
        //需要身份認證
        .authenticated()
        .and()
        //關閉跨站請求防護
        .csrf().disable();
    //默認注銷地址：/logout
    http.logout().
        //注銷之后 跳轉的頁面
        logoutSuccessUrl("/authentication/require");
  }

public class ValidateCodeException extends AuthenticationException {
  public ValidateCodeException(String msg, Throwable t) {
    super(msg, t);
  }

  public ValidateCodeException(String msg) {
    super(msg);
  }
}