/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package org.grails.web.servlet.mvc;

import groovy.lang.Closure;

/**
 * Invokes user code that handles double or invalid submits.
 *
 * @author Graeme Rocher
 * @since 1.1
 */
public interface TokenResponseHandler {

    String INVALID_TOKEN_ATTRIBUTE = "invalidToken";
    String KEY = "org.codehaus.groovy.grails.TOKEN_RESPONSE_HANDLER";

    /**
     * Specify behavior in the event of an invalid token.
     *
     * @param callable The closure to invoke in the event of an invalid token
     * @return A Grails model or null
     */
    Object invalidToken(@SuppressWarnings("rawtypes") Closure callable);

    /**
     * Return whether the response handle was invoked.
     * @return true if it was
     */
    boolean wasInvoked();

    /**
     * Return whether the token was invalid
     * @return true if it was
     */
    boolean wasInvalidToken();
}
