/*
 * @(#)$Id: StringType.java,v 1.19 2002/11/07 16:49:29 kk122374 Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.datatype.xsd;

import org.relaxng.datatype.ValidationContext;
import com.sun.msv.datatype.SerializationContext;

/**
 * "string" type.
 * 
 * type of the value object is <code>java.lang.String</code>.
 * See http://www.w3.org/TR/xmlschema-2/#string for the spec
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public class StringType extends BuiltinAtomicType implements Discrete {
	
	public static final StringType theInstance
		= new StringType("string",WhiteSpaceProcessor.thePreserve,true);
	
    /**
     * Value returned from the isAlwaysValid method.
     */
    private final boolean isAlwaysValid;

    protected StringType( String typeName, WhiteSpaceProcessor whiteSpace ) {
        this( typeName, whiteSpace, false );
    }
    
	protected StringType( String typeName, WhiteSpaceProcessor whiteSpace, boolean _isAlwaysValid ) {
		super(typeName,whiteSpace);
        this.isAlwaysValid = _isAlwaysValid;
	}
	
	public XSDatatype getBaseType() {
		return SimpleURType.theInstance;
	}

	protected final boolean checkFormat( String content, ValidationContext context ) {
		// string derived types should use _createValue method to check its validity
		return _createValue(content,context)!=null;
	}
	
	public Object _createValue( String lexicalValue, ValidationContext context ) {
		// for string, lexical space is value space by itself
		return lexicalValue;
	}
	public Class getJavaObjectType() {
		return String.class;
	}

	public String convertToLexicalValue( Object value, SerializationContext context ) {
		if( value instanceof String )
			return (String)value;
		else
			throw new IllegalArgumentException();
	}
	
	public final int countLength( Object value ) {
		// for string-derived types, length means number of XML characters.
		return UnicodeUtil.countLength( (String)value );
	}
	
	public final int isFacetApplicable( String facetName ) {
		if( facetName.equals(FACET_PATTERN)
		||	facetName.equals(FACET_ENUMERATION)
		||	facetName.equals(FACET_WHITESPACE)
		||	facetName.equals(FACET_LENGTH)
		||	facetName.equals(FACET_MAXLENGTH)
		||	facetName.equals(FACET_MINLENGTH) )
			return APPLICABLE;
		else
			return NOT_ALLOWED;
	}

    public boolean isAlwaysValid() {
        return isAlwaysValid;
    }
}