/*
 *
 */
package org.gcube.datatransfer.resolver.catalogue.resource;

import static org.gcube.resources.discovery.icclient.ICFactory.client;

import java.io.StringReader;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

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

import org.apache.log4j.Logger;
import org.gcube.common.resources.gcore.utils.XPathHelper;
import org.gcube.common.scope.api.ScopeProvider;
import org.gcube.datatransfer.resolver.applicationprofile.ApplicationProfileNotFoundException;
import org.gcube.datatransfer.resolver.applicationprofile.GcubeQuery;
import org.gcube.datatransfer.resolver.applicationprofile.GcubeQuery.FIELD_TYPE;
import org.gcube.datatransfer.resolver.applicationprofile.ScopeUtil;
import org.gcube.resources.discovery.client.api.DiscoveryClient;
import org.gcube.resources.discovery.client.queries.api.Query;
import org.gcube.resources.discovery.client.queries.impl.QueryBox;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.InputSource;


/**
 * The Class ApplicationProfileReaderForCatalogueResolver.
 *
 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
 * Dec 20, 2016
 */
public class ApplicationProfileReaderForCatalogueResolver {

	public static final String VRE_NAME = "VRE_NAME";
	public static final String SCOPE = "SCOPE";
	public static final String END_POINT = "EndPoint";
	public static final String BODY = "Body";


	public static final String SECONDARY_TYPE = "ApplicationProfile";
	public static final String RESOURCE_NAME = "Catalogue-Resolver";
	protected static final String RESOURCE_PROFILE_NAME_TEXT = "/Resource/Profile/Name/text()";
	protected static final String RESOURCE_PROFILE_DESCRIPTION_TEXT = "/Resource/Profile/Description/text()";
	protected static final String RESOURCE_PROFILE_BODY_END_POINT_SCOPE_TEXT = "/Resource/Profile/"+BODY+"/"+END_POINT+"/"+SCOPE+"/text()";
	protected static final String RESOURCE_PROFILE_BODY_END_POINT_VRE_NAME_TEXT = "/Resource/Profile/"+BODY+"/"+END_POINT+"/"+VRE_NAME+"/text()";


	private Logger logger = Logger.getLogger(ApplicationProfileReaderForCatalogueResolver.class);
	private String secondaryType;
	private String resourceName;
	private String scope;
	private boolean useRootScope = false;
	private Document document;

	/** The hash vre name scope.
	 *  Used by Catalogue Resolver for mapping VRE NAME with its SCOPE where to fetch the Data Catalogue Portlet so that resolve correctly URL of
	 *  kind: http://[CATALOGUE_RESOLVER_SERVLET]/[VRE_NAME]/[entity_context value]/[entity_name value]
	 * */
	private Map<String, String> hashVreNameScope = new HashMap<String, String>();
	private Element rootElement;

	/**
	 * Instantiates a new application profile reader for catalogue resolver.
	 *
	 * @param scope the scope
	 * @param useRootScope the use root scope
	 */
	public ApplicationProfileReaderForCatalogueResolver(String scope, boolean useRootScope) {
		this.scope = scope;
		this.secondaryType = SECONDARY_TYPE;
		this.resourceName = RESOURCE_NAME;
		this.useRootScope = useRootScope;
		this.readProfileFromInfrastrucure();
	}

	/**
	 * Read profile from infrastrucure and fills the map {@link #hashVreNameScope}.
	 */
	private void readProfileFromInfrastrucure() {

		String queryString = GcubeQuery.getGcubeGenericResource(secondaryType, FIELD_TYPE.RESOURCE_NAME, resourceName);

		try {
			logger.info("Trying to fetch ApplicationProfile in the scope: "+ScopeProvider.instance.get()+", SecondaryType: " + secondaryType + ", ResourceName: " +  resourceName);
			Query q = new QueryBox(queryString);
			DiscoveryClient<String> client = client();
			List<String> appProfile = client.submit(q);

			if (appProfile == null || appProfile.size() == 0)
				throw new ApplicationProfileNotFoundException("ApplicationProfile with SecondaryType: " + secondaryType + ", ResourceName: " +  resourceName +" is not registered in the scope: "+ScopeProvider.instance.get());
			else {
				try{
					String elem = appProfile.get(0);
					DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
					document = docBuilder.parse(new InputSource(new StringReader(elem)));
					rootElement = document.getDocumentElement();
					XPathHelper helper = new XPathHelper(rootElement);
					List<String> scopes = helper.evaluate(RESOURCE_PROFILE_BODY_END_POINT_SCOPE_TEXT);
					for (String scopeFound : scopes) {
						List<String> vreName = helper.evaluate("/Resource/Profile/Body/EndPoint[SCOPE='"+scopeFound.toString()+"']/VRE_NAME/text()");
						logger.info("For scope: "+scopeFound+", found VRE_NAME "+vreName);
						hashVreNameScope.put(vreName.get(0), scopeFound);
					}
				}catch(Exception e){
					throw new ApplicationProfileNotFoundException("Error during parsing application profile with resource name: "+resourceName + " in the scope: "+scope.toString());
				}
			}

		} catch (Exception e) {
			logger.error("Error while trying to fetch applicationProfile profile from the infrastructure", e);
		}

	}



	/**
	 * Gets the root document.
	 *
	 * @return the rootDocument
	 */
	public Element getRootDocument() {

		return rootElement;
	}


	/**
	 * Gets the document.
	 *
	 * @return the document
	 */
	public Document getDocument(){
		return document;
	}


	/**
	 * Gets the hash vre name scope.
	 *
	 * @return the hashVreNameScope
	 */
	public Map<String, String> getHashVreNameScope() {

		return hashVreNameScope;
	}

	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {

		StringBuilder builder = new StringBuilder();
		builder.append("ApplicationProfileReaderForCatalogueResolver [logger=");
		builder.append(logger);
		builder.append(", secondaryType=");
		builder.append(secondaryType);
		builder.append(", resourceName=");
		builder.append(resourceName);
		builder.append(", scope=");
		builder.append(scope);
		builder.append(", useRootScope=");
		builder.append(useRootScope);
		builder.append(", hashVreNameScope=");
		builder.append(hashVreNameScope);
		builder.append("]");
		return builder.toString();
	}


	/*public static void main(String[] args) {
		String scope ="/gcube";
		ApplicationProfileReaderForCatalogueResolver reader = new ApplicationProfileReaderForCatalogueResolver(scope, true);
		System.out.println(reader);
	}*/
}