/**
 *
 */
package org.gcube.datatransfer.resolver.services;

import java.net.URI;
import java.util.concurrent.ExecutionException;

import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Response;

import org.gcube.datatransfer.resolver.applicationprofile.ApplicationProfileReader;
import org.gcube.datatransfer.resolver.caches.LoadingVREsScopeCache;
import org.gcube.datatransfer.resolver.services.error.ExceptionManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/**
 * The Class AnalyticsGetResolver.
 *
 * @author Francesco Mangiacrapa at ISTI-CNR (francesco.mangiacrapa@isti.cnr.it)
 * Dec 13, 2018
 */
@Path("/analytics")
public class AnalyticsGetResolver {

	private static Logger logger = LoggerFactory.getLogger(AnalyticsGetResolver.class);

	private static final String ORG_GCUBE_PORTLETS_USER_DATAMINERMANAGER_SERVER_DATA_MINER_MANAGER_SERVICE_IMPL =
		"org.gcube.portlets.user.dataminermanager.server.DataMinerManagerServiceImpl";

	private static final String APPLICATION_PROFILE = "ApplicationProfile";

	private static String helpURI = "https://gcube.wiki.gcube-system.org/gcube/URI_Resolver#Analytics_Resolver";

	private static final String ANALYTICS_EXECUTOR_PORTLET_NAME = "Analytics Executor";


	/**
	 * Resolve analytics url.
	 *
	 * @param req the req
	 * @param vreName the vre name
	 * @return the response
	 */
	@GET
	@Path("/get/{vreName}")
	public Response resolveAnalyticsURL(@Context HttpServletRequest req, @PathParam("vreName") String vreName) throws WebApplicationException{
		logger.info(this.getClass().getSimpleName()+" GET starts...");
		try {

			if(vreName==null || vreName.isEmpty()){
				logger.error("The path parameter 'vreName' not found or empty in the path");
				throw ExceptionManager.badRequestException(req, "Mandatory path parameter 'vreName' not found or empty", this.getClass(), helpURI);
			}

			String fullScope = "";

			//CHECKING IF THE INPUT VRE NAME IS REGISTRED IN THE INFRASTRUCTURE...
			try{
				fullScope = LoadingVREsScopeCache.get(vreName);
			}catch(ExecutionException e){
				logger.error("Error on getting the fullscope from cache for vreName "+vreName, e);
				throw ExceptionManager.wrongParameterException(req, "Error on getting full scope for the VRE name "+vreName+". Is it registered as VRE in the D4Science Infrastructure System?", this.getClass(), helpURI);
			}
			ApplicationProfileReader reader = null;
			try{
				reader = new ApplicationProfileReader(fullScope, APPLICATION_PROFILE, ORG_GCUBE_PORTLETS_USER_DATAMINERMANAGER_SERVER_DATA_MINER_MANAGER_SERVICE_IMPL, false);
			}catch(Exception e){
				logger.error("Error on reading the "+APPLICATION_PROFILE+" with APPID: "+ORG_GCUBE_PORTLETS_USER_DATAMINERMANAGER_SERVER_DATA_MINER_MANAGER_SERVICE_IMPL, e);
				throw ExceptionManager.internalErrorException(req, "Error on reading the Application Profile for the "+ANALYTICS_EXECUTOR_PORTLET_NAME+". Please contact the support", this.getClass(), helpURI);
			}

			//READ THE DATAMINER URL PORTLET FROM APPLICATION PROFRILE IN THE SCOPE fullScope
			String analyticsExecutorEndPoint = reader.getApplicationProfile().getUrl();
			//CHECKING THE QUERY STRING
			String queryString = req.getQueryString()!=null?req.getQueryString():"";
			String analitycsExecutorURL = String.format("%s?%s", analyticsExecutorEndPoint, queryString);
			logger.info("Resolving the request with the "+ANALYTICS_EXECUTOR_PORTLET_NAME+" URL: "+analitycsExecutorURL);
			return Response.seeOther(new URI(analitycsExecutorURL)).build();

		}catch (Exception e) {

			if(!(e instanceof WebApplicationException)){
				//UNEXPECTED EXCEPTION managing it as WebApplicationException
				String error = "Error occurred on resolving the Analytics URL. Please, contact the support!";
				if(e.getCause()!=null)
					error+="\n\nCaused: "+e.getCause().getMessage();
				throw ExceptionManager.internalErrorException(req, error, this.getClass(), helpURI);
			}
			//ALREADY MANAGED AS WebApplicationException
			logger.error("Exception:", e);
			throw (WebApplicationException) e;
		}
	}

}