/*
 * 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.xerces.impl.dv.dtd;

import org.apache.xerces.impl.dv.*;
import org.apache.xerces.util.XMLChar;

/**
 * <P>IDDatatypeValidator - ID represents the ID attribute
 * type from XML 1.0 Recommendation. The value space
 * od ID is the set of all strings that match the
 * NCName production and have been used in an XML
 * document. The lexical space of ID is the set of all
 * strings that match the NCName production.</P>
 * <P>The value space of ID is scoped to a specific
 * instance document.</P>
 * <P>The following constraint applies:
 * An ID must not appear more than once in an XML
 * document as a value of this type; i.e., ID values
 * must uniquely identify the elements which bear
 * them.</P>
 *
 * @xerces.internal  
 * 
 * @author Jeffrey Rodriguez, IBM
 * @author Sandy Gao, IBM
 * 
 * @version $Id: IDDatatypeValidator.java 446749 2006-09-15 21:51:23Z mrglavas $
 */
public class IDDatatypeValidator implements DatatypeValidator {

    // construct an ID datatype validator
    public IDDatatypeValidator() {
    }

    /**
     * Checks that "content" string is valid ID value.
     * If invalid a Datatype validation exception is thrown.
     * 
     * @param content       the string value that needs to be validated
     * @param context       the validation context
     * @throws InvalidDatatypeException if the content is
     *         invalid according to the rules for the validators
     * @see InvalidDatatypeValueException
     */
    public void validate(String content, ValidationContext context) throws InvalidDatatypeValueException {

        //Check if is valid key-[81] EncName ::= [A-Za-z] ([A-Za-z0-9._] | '-')*
        if(context.useNamespaces()) {
            if (!XMLChar.isValidNCName(content)) {
                throw new InvalidDatatypeValueException("IDInvalidWithNamespaces", new Object[]{content});
            }
        }
        else {
            if (!XMLChar.isValidName(content)) {
                throw new InvalidDatatypeValueException("IDInvalid", new Object[]{content});
            }
        }

        if (context.isIdDeclared(content)) {
            throw new InvalidDatatypeValueException("IDNotUnique", new Object[]{content});
        }
        
        context.addId(content);
    }
    
}