/*

Copyright 2010,2011 Google Inc.
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    * Redistributions of source code must retain the above copyright
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    * Redistributions in binary form must reproduce the above
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contributors may be used to endorse or promote products derived from
this software without specific prior written permission.

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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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*/

package com.google.refine.expr.functions.xml;

import java.util.Properties;

import org.jsoup.nodes.Element;

import com.google.refine.expr.EvalError;
import com.google.refine.grel.ControlFunctionRegistry;
import com.google.refine.grel.Function;

public class XmlText implements Function {

    @Override
    public Object call(Properties bindings, Object[] args) {
        if (args.length == 1) {
            Object o1 = args[0];
            if (o1 != null && o1 instanceof Element) {
                Element e1 = (Element)o1;
                return e1.text();

            }else{
                return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " failed as the first parameter is not an XML or HTML Element.  Please first use parseXml() or parseHtml() and select(query) prior to using this function");
            }
        }
        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a single XML or HTML element as an argument");
    }


    @Override
    public String getDescription() {
        return "Selects the text from within an element (including all child elements)";
    }
    
    @Override
    public String getParams() {
        return "Element e";
    }
    
    @Override
    public String getReturns() {
        return "String text";
    }
}

