/*
 *  eXist Open Source Native XML Database
 *  Copyright (C) 2001-06 Wolfgang M. Meier
 *  wolfgang@exist-db.org
 *  http://exist.sourceforge.net
 *  
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *  
 *  This program 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 Lesser General Public License for more details.
 *  
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *  
 *  $Id$
 */
package org.exist.xquery;

import org.exist.xquery.util.ExpressionDumper;
import org.exist.xquery.value.AtomicValue;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.Type;

/**
 * A literal value, i.e. a string, integer, decimal or double literal.
 * 
 * This is just a wrapper around the corresponding atomic value.
 * 
 * @author wolf
 */
public class LiteralValue extends AbstractExpression {

	private AtomicValue value;
	
	public LiteralValue(XQueryContext context, AtomicValue value) {
		super(context);
		this.value = value;
	}
	
	public AtomicValue getValue() {
		return value;
	}
	
	public void setValue(AtomicValue value) {
		this.value = value;
	}
	
    /* (non-Javadoc)
     * @see org.exist.xquery.Expression#analyze(org.exist.xquery.AnalyzeContextInfo)
     */
    public void analyze(AnalyzeContextInfo contextInfo) throws XPathException {
        contextInfo.setStaticReturnType(value.getType());
    }
    
	/* (non-Javadoc)
	 * @see org.exist.xquery.Expression#eval(org.exist.xquery.StaticContext, org.exist.dom.DocumentSet, org.exist.xquery.value.Sequence, org.exist.xquery.value.Item)
	 */
	public Sequence eval(
		Sequence contextSequence,
		Item contextItem)
		throws XPathException {
		return value;
	}

	/* (non-Javadoc)
     * @see org.exist.xquery.Expression#dump(org.exist.xquery.util.ExpressionDumper)
     */
    public void dump(ExpressionDumper dumper) {
        if(Type.subTypeOf(value.getType(), Type.STRING)) {
            dumper.display("\"");
            value.dump(dumper);
            dumper.display("\"");
        } else
            value.dump(dumper);
    }
    
    public String toString() {
    	StringBuilder result = new StringBuilder();
        if(Type.subTypeOf(value.getType(), Type.STRING)) {
        	result.append("\"");
        	result.append(value.toString());
        	result.append("\"");
        } else
        	result.append(value.toString());
        return result.toString();
    }    
    
	/* (non-Javadoc)
	 * @see org.exist.xquery.Expression#returnsType()
	 */
	public int returnsType() {
		return value.getType();
	}
	
	/* (non-Javadoc)
	 * @see org.exist.xquery.AbstractExpression#getDependencies()
	 */
	public int getDependencies() {
		return Dependency.NO_DEPENDENCY;
	}

	/* (non-Javadoc)
	 * @see org.exist.xquery.AbstractExpression#getCardinality()
	 */
	public int getCardinality() {
		return Cardinality.EXACTLY_ONE;
	}

	/* (non-Javadoc)
	 * @see org.exist.xquery.AbstractExpression#resetState()
	 */
	public void resetState(boolean postOptimization) {
	}
}