package com.atlassian.sal.core.xsrf;
   
   import com.atlassian.sal.api.xsrf.XsrfTokenAccessor;
   import com.atlassian.security.random.DefaultSecureTokenGenerator;
   import com.atlassian.security.random.SecureTokenGenerator;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   
   import javax.servlet.http.Cookie;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  /**
   * XSRF token accessor that manages its own tokens, not using the underlying applications XSRF tokens
   *
   * @since 2.4
   */
  public class IndependentXsrfTokenAccessor implements XsrfTokenAccessor
  {
      private static final Logger log = LoggerFactory.getLogger(IndependentXsrfTokenAccessor.class);
      public static final String XSRF_COOKIE_KEY = "atl.xsrf.token";
  
      private final SecureTokenGenerator tokenGenerator = DefaultSecureTokenGenerator.getInstance();
  
      public String getXsrfToken(final HttpServletRequest request, final HttpServletResponse response, final boolean create)
      {
          Cookie[] cookies = request.getCookies();
          if (cookies != null)
          {
              for (Cookie cookie : request.getCookies())
              {
                  if (cookie.getName().equals(XSRF_COOKIE_KEY))
                  {
                      return cookie.getValue();
                  }
              }
          }
          if (create)
          {
              if (response.isCommitted())
              {
                  log.warn("Adding cookie to committed response, this will likely have no effect");
              }
              String token = tokenGenerator.generateToken();
              Cookie cookie = new Cookie(XSRF_COOKIE_KEY, token);
              response.addCookie(cookie);
              return token;
          }
          return null;
      }
  }