/**
 *
 */
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.common.scope.impl.ScopeBean;
import org.gcube.datatransfer.resolver.applicationprofile.ApplicationProfileReader;
import org.gcube.datatransfer.resolver.caches.LoadingMapOfScopeCache;
import org.gcube.datatransfer.resolver.services.error.ExceptionManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.cache.CacheLoader.InvalidCacheLoadException;

/**
 * The AnalyticsGetResolver to resolve an Analytics URL
 * 
 * See more at
 * https://gcube.wiki.gcube-system.org/gcube/URI_Resolver#Analytics_Resolver
 *
 * @author Francesco Mangiacrapa at ISTI-CNR francesco.mangiacrapa@isti.cnr.it
 * 
 *         Mar 24, 2022
 */
@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.
	 *
	 * See more at
	 * https://gcube.wiki.gcube-system.org/gcube/URI_Resolver#HTTP_GET:_Resolve_an_Analytics_URL
	 * 
	 * @param req     the req
	 * @param vreName the vre name
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@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);
			}

			ScopeBean fullScopeBean = null;

			// CHECKING IF THE INPUT VRE NAME IS REGISTRED IN THE INFRASTRUCTURE...
			try {
				fullScopeBean = LoadingMapOfScopeCache.get(vreName);
			} catch (ExecutionException | InvalidCacheLoadException 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(fullScopeBean.toString(), 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;
		}
	}

}