/*
    * 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.layout;
  
  import java.util.StringTokenizer;
  
  /**
   * Basic helper type for the CSS3 Grid property.
   * Limitations: "auto" is not supported by IE 10/11.
   */
  public class GridSpan {
  
    private Integer start;
    private Integer span;
  
    private GridSpan() {
    }
  
    public static GridSpan valueOf(final String string) {
      final GridSpan item = new GridSpan();
      final StringTokenizer tokenizer = new StringTokenizer(string, " /");
      if (tokenizer.hasMoreElements()) {
        item.start = Integer.parseInt(tokenizer.nextToken());
      }
      if (tokenizer.hasMoreElements()) {
        final String next = tokenizer.nextToken();
        if (next.equals("span")) {
          item.span = Integer.parseInt(tokenizer.nextToken());
        } else {
          item.span = Integer.parseInt(next) - item.start;
        }
      }
      return item;
    }
  
    public static GridSpan valueOf(final Integer start, final Integer span) {
      final GridSpan item = new GridSpan();
      item.start = start;
      item.span = span;
      return item;
    }
  
    public String encode() {
      if (start != null) {
        if (span != null && span != 1) {
          return start + "/span " + span;
        } else {
          return start.toString();
        }
      } else {
        if (span != null && span != 1) { // XXX "auto" not supported by MS IE
          return "auto/span " + span;
        } else {
          return "auto";
        }
      }
    }
  
    public Integer getStart() {
      return start;
    }
  
    public Integer getSpan() {
      return span;
    }
  }