ckan2zenodo-library/ckan2zenodo-library/src/main/java/org/gcube/data/publishing/ckan2zenodo/TransformerManager.java

package org.gcube.data.publishing.ckan2zenodo;

import java.util.ArrayList;
import java.util.HashMap;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.gcube.common.resources.gcore.GenericResource;
import org.gcube.data.publishing.ckan2zenodo.commons.IS;
import org.gcube.data.publishing.ckan2zenodo.model.Mapping;
import org.gcube.data.publishing.ckan2zenodo.model.Mapping.Regexp;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

import lombok.Synchronized;


public class TransformerManager {



	private static DocumentBuilder builder=null;

	@Synchronized	
	private static DocumentBuilder getBuilder() throws ParserConfigurationException {
		if(builder==null) {
			DocumentBuilderFactory factory =DocumentBuilderFactory.newInstance();
			builder = factory.newDocumentBuilder();
		}
		return builder;
	}

	public Transformer getByProfile(String profile) throws Exception {
		for(GenericResource r: IS.queryForGenericResources("Ckan-Zenodo-Mappings")){
			if (r.profile().name().equals(profile))
				return new Transformer(readMappings(r));
		}
		throw new Exception("No transformer found for profile "+profile);
	}



	private static ArrayList<Mapping> readMappings(GenericResource res){
		//		ByteArrayInputStream input =  new ByteArrayInputStream(
		//				   res.profile()..toString().getBytes("UTF-8"));
		//				Document doc = builder.parse(input);
		//		XPath xPath =  XPathFactory.newInstance().newXPath();
		//		String expression = "/class/student";	        
		//		NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(
		//		   doc, XPathConstants.NODESET);

		ArrayList<Mapping> toReturn=new ArrayList<Mapping>();

		Element root=res.profile().body();
		NodeList mappings=root.getElementsByTagName("mapping");

		for(int i = 0; i<mappings.getLength();i++) {
			Element mapping=(Element) mappings.item(i);
			String source=mapping.getElementsByTagName("source").item(0).getTextContent();
			String target=mapping.getElementsByTagName("target").item(0).getTextContent();

			HashMap<String,String> values=new HashMap<>();
			NodeList valueMappings=mapping.getElementsByTagName("valueMapping");
			for(int j = 0; i<valueMappings.getLength();j++) {
				Element codelistMapping=(Element) valueMappings.item(j);
				String sourceValue=codelistMapping.getElementsByTagName("sourceValue").item(0).getTextContent();
				String targetValue=codelistMapping.getElementsByTagName("targetValue").item(0).getTextContent();
				values.put(sourceValue, targetValue);
			}

			ArrayList<Regexp> regularExpressions=new ArrayList<>();
			NodeList regexpDeclarations=mapping.getElementsByTagName("regexp");
			for(int j = 0; i<regexpDeclarations.getLength();j++) {
				Element regexpElement=(Element) regexpDeclarations.item(j);
				String regexpTarget=regexpElement.getElementsByTagName("target").item(0).getTextContent();
				String typeName=regexpElement.getAttribute("type");
				Regexp regexp=new Regexp(Regexp.Type.valueOf(typeName),regexpTarget);
				if(regexp.getType().equals(Regexp.Type.replace))
					regexp.setReplacement(regexpElement.getElementsByTagName("replacement").item(0).getTextContent());
				regularExpressions.add(regexp);

			}


			toReturn.add(new Mapping(source,target,values,regularExpressions));

		}

		return toReturn;

	}
}