/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Rhino code, released
 * May 6, 1999.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1997-1999
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Steve Yegge
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License Version 2 or later (the "GPL"), in which
 * case the provisions of the GPL are applicable instead of those above. If
 * you wish to allow use of your version of this file only under the terms of
 * the GPL and not to allow others to use your version of this file under the
 * MPL, indicate your decision by deleting the provisions above and replacing
 * them with the notice and other provisions required by the GPL. If you do
 * not delete the provisions above, a recipient may use your version of this
 * file under either the MPL or the GPL.
 *
 * ***** END LICENSE BLOCK ***** */

package org.mozilla.javascript.ast;

import org.mozilla.javascript.Token;

/**
 * AST node for an embedded JavaScript expression within an E4X XML literal.
 * Node type, like {@link XmlLiteral}, is {@link Token#XML}.  The node length
 * includes the curly braces.
 */
public class XmlExpression extends XmlFragment {

    private AstNode expression;
    private boolean isXmlAttribute;

    public XmlExpression() {
    }

    public XmlExpression(int pos) {
        super(pos);
    }

    public XmlExpression(int pos, int len) {
        super(pos, len);
    }

    public XmlExpression(int pos, AstNode expr) {
        super(pos);
        setExpression(expr);
    }

    /**
     * Returns the expression embedded in {}
     */
    public AstNode getExpression() {
        return expression;
    }

    /**
     * Sets the expression embedded in {}, and sets its parent to this node.
     * @throws IllegalArgumentException if {@code expression} is {@code null}
     */
    public void setExpression(AstNode expression) {
        assertNotNull(expression);
        this.expression = expression;
        expression.setParent(this);
    }

    /**
     * Returns whether this is part of an xml attribute value
     */
    public boolean isXmlAttribute() {
      return isXmlAttribute;
    }

    /**
     * Sets whether this is part of an xml attribute value
     */
    public void setIsXmlAttribute(boolean isXmlAttribute) {
      this.isXmlAttribute = isXmlAttribute;
    }

    @Override
    public String toSource(int depth) {
        return makeIndent(depth) + "{" + expression.toSource(depth) + "}";
    }

    /**
     * Visits this node, then the child expression.
     */
    @Override
    public void visit(NodeVisitor v) {
        if (v.visit(this)) {
            expression.visit(v);
        }
    }
}