/*
 * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
 * Copyright (C) 2004-2011
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.sun.xml.internal.rngom.binary;

import com.sun.xml.internal.rngom.binary.visitor.PatternFunction;
import com.sun.xml.internal.rngom.binary.visitor.PatternVisitor;

public class ChoicePattern extends BinaryPattern {
  ChoicePattern(Pattern p1, Pattern p2) {
    super(p1.isNullable() || p2.isNullable(),
          combineHashCode(CHOICE_HASH_CODE, p1.hashCode(), p2.hashCode()),
          p1,
          p2);
  }
  Pattern expand(SchemaPatternBuilder b) {
    Pattern ep1 = p1.expand(b);
    Pattern ep2 = p2.expand(b);
    if (ep1 != p1 || ep2 != p2)
      return b.makeChoice(ep1, ep2);
    else
      return this;
  }

  boolean containsChoice(Pattern p) {
    return p1.containsChoice(p) || p2.containsChoice(p);
  }

  public void accept(PatternVisitor visitor) {
    visitor.visitChoice(p1, p2);
  }

  public Object apply(PatternFunction f) {
    return f.caseChoice(this);
  }

  void checkRestrictions(int context, DuplicateAttributeDetector dad, Alphabet alpha)
    throws RestrictionViolationException {
    if (dad != null)
      dad.startChoice();
    p1.checkRestrictions(context, dad, alpha);
    if (dad != null)
      dad.alternative();
    p2.checkRestrictions(context, dad, alpha);
    if (dad != null)
      dad.endChoice();
  }

}