D-Net

package eu.dnetlib.data.search.transform.formatter;

import eu.dnetlib.data.search.transform.FormatterException;

import eu.dnetlib.data.search.transform.utils.VelocityUtil;

import eu.dnetlib.domain.data.SearchResult;

import org.apache.commons.io.IOUtils;

import org.apache.commons.lang.StringEscapeUtils;

import org.apache.log4j.Logger;

import org.apache.velocity.Template;

import org.apache.velocity.VelocityContext;

import org.apache.velocity.app.VelocityEngine;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.stream.StreamResult;

import javax.xml.transform.stream.StreamSource;

import java.io.InputStream;

import java.io.StringReader;

import java.io.StringWriter;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

public class SimpleFormatter implements Formatter {

	private javax.xml.transform.Transformer xmlTransformer = null;

	private StringWriter xmlResultResource = new StringWriter();

	private Template t = null;

	private final Logger logger = Logger.getLogger(SimpleFormatter.class);

	public SimpleFormatter() throws FormatterException{

        StringWriter writer = null;

        InputStream inputStream = null;

        try	{

            VelocityEngine ve = VelocityUtil.getEngine();

            String clean_xsl = "/eu/dnetlib/data/search/transform/config/omit-xml-declaration.xsl";

			t = ve.getTemplate("/eu/dnetlib/data/search/transform/config/format.vm", "UTF-8");

            inputStream = this.getClass().getResource(clean_xsl).openStream();

			writer = new StringWriter();

			IOUtils.copy(inputStream, writer);		

            String xsl = writer.toString();

			synchronized(this) {

				xmlTransformer = TransformerFactory.newInstance().newTemplates(new StreamSource(new StringReader(xsl))).newTransformer();

                xmlTransformer.setOutputProperty("encoding", "UTF-8");

			}

		} catch (Exception e) {

			logger.error("Error while creating a velocity template.", e);

			throw new FormatterException("Error while creating a velocity template.", e);

		} finally {

            IOUtils.closeQuietly(writer);

            IOUtils.closeQuietly(inputStream);

        }

	}

    public SimpleFormatter(String template) throws FormatterException {

        StringWriter writer = null;

        InputStream inputStream = null;

        logger.debug("Creating formatter with template " + template);

        try	{

            VelocityEngine ve = VelocityUtil.getEngine();

            String clean_xsl = "/eu/dnetlib/data/search/transform/config/omit-xml-declaration.xsl";

            t = ve.getTemplate("/eu/dnetlib/data/search/transform/config/" + template, "UTF-8");

            inputStream = this.getClass().getResource(clean_xsl).openStream();

            writer = new StringWriter();

            IOUtils.copy(inputStream, writer);

            String xsl = writer.toString();

            synchronized(this) {

                xmlTransformer = TransformerFactory.newInstance().newTemplates(new StreamSource(new StringReader(xsl))).newTransformer();

            }

        } catch (Exception e) {

            logger.error("Error while creating a velocity template.", e);

            throw new FormatterException("Error while creating a velocity template.", e);

        } finally {

            IOUtils.closeQuietly(writer);

            IOUtils.closeQuietly(inputStream);

        }

    }

	@Override

	public String format(SearchResult result) throws FormatterException {

		VelocityContext context = null;

		try {

			context = new VelocityContext();

		} catch (Exception e) {

			logger.error("Error while creating a Velocity context.", e);

			FormatterException fe = new FormatterException("Error while creating a Velocity context.", e);

			throw fe;

		}

		try {

			context.put("page", result.getPage());

			context.put("query", StringEscapeUtils.escapeXml(result.getQuery()));

			context.put("size", result.getSize());

			context.put("total", result.getTotal());

			context.put("locale", result.getLocale());

			context.put("fields", result.getFields());

            SimpleDateFormat sdf = new SimpleDateFormat("EEE, d MMM yy HH:mm:ss z");

            context.put("currentDate", sdf.format(new Date()));

			if(result.getSearchResults() == null)

				context.put("results",null);

			else {

             //   logger.debug("After: " + clearDeclarations(result.getSearchResults()));

                context.put("results", clearDeclarations(result.getSearchResults()));

            }

			if (result.getBrowseResults() == null)

				context.put("bresults",null);

			else

				context.put("bresults", clearDeclarations(result.getBrowseResults()));

			StringWriter writer = new StringWriter();

            //logger.debug("formating with " + t.getName() + "and results " + result.getSearchResults());

			t.merge(context, writer);

			return writer.toString();

		} catch (Exception e) {

			String text = "Error while formatting.";

			if(result == null)

				text += " And result is null.";

			logger.error(text, e);

			FormatterException fe = new FormatterException("Error while formatting.", e);

			throw fe;

		}

	}

	public List<String> clearDeclarations(List<String> results) throws FormatterException{

		List<String> cleared = new ArrayList<String>();

		for(String result: results){

			xmlResultResource.getBuffer().setLength(0);		

			try {

				xmlTransformer.transform(new StreamSource(new StringReader(result)), new StreamResult(xmlResultResource));

			} catch (Exception e) {

				logger.warn("Error transforming xml.", e);

				throw new FormatterException();

			}

			cleared.add(xmlResultResource.getBuffer().toString());

		}

		return cleared;

	}

}