/**
 * Copyright (C) 2010 Orbeon, Inc.
 *
 * 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
 * 2.1 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.
 *
 * The full text of the license is available at http://www.gnu.org/copyleft/lesser.html
 */
package org.orbeon.oxf.processor.pipeline.functions;

import org.orbeon.oxf.util.URLRewriterUtils;
import org.orbeon.saxon.expr.Expression;
import org.orbeon.saxon.expr.ExpressionTool;
import org.orbeon.saxon.expr.ExpressionVisitor;
import org.orbeon.saxon.expr.XPathContext;
import org.orbeon.saxon.functions.SystemFunction;
import org.orbeon.saxon.om.Item;
import org.orbeon.saxon.trans.XPathException;
import org.orbeon.saxon.value.StringValue;

public class DecodeResourceURI extends SystemFunction {

    /**
     * preEvaluate: this method suppresses compile-time evaluation by doing nothing
     * (because the value of the expression depends on the runtime context)
     */
    @Override
    public Expression preEvaluate(ExpressionVisitor visitor) throws XPathException {
        return this;
    }

    @Override
    public Item evaluateItem(XPathContext xpathContext) throws XPathException {
        // Evaluate parameters
        final String uri = argument[0].evaluateAsString(xpathContext).toString();
        final boolean isVersioned = ExpressionTool.effectiveBooleanValue(argument[1].iterate(xpathContext));

        // Get property value
        final String rewrittenURI = URLRewriterUtils.decodeResourceURI(uri, isVersioned);
        return StringValue.makeStringValue(rewrittenURI);
    }
}