package org.itsnat.droid.impl.domparser;

import android.util.Xml;

import org.itsnat.droid.ItsNatDroidException;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;

/**
 * Created by jmarranz on 11/05/2016.
 */
public class XMLDOMAnimDiscriminatorParser
{
    private static XmlPullParser newPullParser(Reader input)
    {
        try
        {
            XmlPullParser parser = Xml.newPullParser();
            // No es necesario, así es más rápido: parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, true);
            parser.setInput(input);
            return parser;
        }
        catch (XmlPullParserException ex)
        {
            throw new ItsNatDroidException(ex);
        }
    }

    public String parse(String markup)
    {
        StringReader input = new StringReader(markup);
        return parse(input);
    }

    private String parse(Reader input)
    {
        try
        {
            XmlPullParser parser = newPullParser(input);
            return parse(parser);
        }
        catch (IOException ex) { throw new ItsNatDroidException(ex); }
        catch (XmlPullParserException ex) { throw new ItsNatDroidException(ex); }
        finally
        {
            try { input.close(); }
            catch (IOException ex) { throw new ItsNatDroidException(ex); }
        }
    }

    private String parse(XmlPullParser parser) throws IOException, XmlPullParserException
    {
        return getRootElementName(parser);
    }

    protected static String getRootElementName(XmlPullParser parser) throws IOException, XmlPullParserException
    {
        while (parser.next() != XmlPullParser.END_TAG)
        {
            if (parser.getEventType() != XmlPullParser.START_TAG) // Nodo de texto etc
                continue;

            return parser.getName();
        }

        throw new ItsNatDroidException("INTERNAL ERROR: NO ROOT ELEMENT");
    }
}