/*
    * 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
    *
   *   http://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.apache.myfaces.tobago.internal.taglib.component;
  
  import javax.servlet.jsp.tagext.TagData;
  import javax.servlet.jsp.tagext.TagExtraInfo;
  import javax.servlet.jsp.tagext.ValidationMessage;
  
  public class CommandTagExtraInfo extends TagExtraInfo {
    private static final ValidationMessage[] EMPTY_MESSAGE = new ValidationMessage[0];
  
    public ValidationMessage[] validate(TagData data) {
      Object action = data.getAttribute("action");
      Object onclick = data.getAttribute("onclick");
      Object link = data.getAttribute("link");
  
      if (link != null && !(action == null && onclick == null)) {
        return generateValidationMessages(data);
      }
      return EMPTY_MESSAGE;
    }
  
    private ValidationMessage[] generateValidationMessages(TagData data) {
      ValidationMessage[] messages = new ValidationMessage[1];
      messages[0] = new ValidationMessage(data.getId(),
          "Only one Attribute of action, onclick and link is allowed");
      return messages;
    }
  }