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

import java.io.UnsupportedEncodingException;
import java.net.URI;
import java.net.URLEncoder;
import java.util.Map;
import java.util.concurrent.ExecutionException;

import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.gcube.common.scope.impl.ScopeBean;
import org.gcube.common.scope.impl.ScopeBean.Type;
import org.gcube.datatransfer.resolver.caches.LoadingVREsScopeCache;
import org.gcube.datatransfer.resolver.dataminer.DataMinerRequest;
import org.gcube.datatransfer.resolver.services.error.ExceptionManager;
import org.gcube.datatransfer.resolver.util.Util;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/**
 * The Class DataMinerResolver.
 *
 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
 * Nov 28, 2018
 */
@Path("/dataminer")
public class DataMinerResolver {


	/**
	 *
	 */
	private static final String UTF_8 = "UTF-8";
	private static Logger logger = LoggerFactory.getLogger(CatalogueResolver.class);
	private static String helpURI = "https://wiki.gcube-system.org/gcube/URI_Resolver";


	/**
	 * Gets the data miner.
	 *
	 * @param req the req
	 * @param provider the provider
	 * @param path the path
	 * @param remainPath the remain path
	 * @return the data miner
	 */
	@GET
	@Path("/{vreName}/{operatorId}")
	public Response getDataMiner(@Context HttpServletRequest req, @PathParam("vreName") String vreName, @PathParam("operatorId") String operatorId) {
		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");
				ExceptionManager.throwBadRequestException(req, "Mandatory path parameter 'vreName' not found or empty", this.getClass(), helpURI);
			}


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

			try{
				String fullScope = LoadingVREsScopeCache.getCache().get(vreName);

				//READ THE DATAMINER URL PORTLET FROM APPLICATION PROFRILE IN THE SCOPE fullScope
				String dataminerEndPoint = "https://pre.d4science.org/group/prevre/dataminer-manager";

				String queryString = "OperatorId="+URLEncoder.encode(operatorId, UTF_8);
				if(req.getQueryString()!=null && !req.getQueryString().isEmpty()){
					queryString+="&"+req.getQueryString();
				}

				String dataMinerResolveURL = String.format("%s?%s", dataminerEndPoint, queryString);
				logger.info("Resolving the request as DataMinerURL: "+dataMinerResolveURL);
				return Response.seeOther(new URI(dataMinerResolveURL)).build();

			}catch (ExecutionException e) {
				logger.error("The input VRE Name "+vreName+" not found", e);
				ExceptionManager.throwBadRequestException(req, "The input 'VRE Name' "+"+vreName+"+ "not found on Informatiion System. Is it a valid VRE?", this.getClass(), helpURI);
			}

			return null;
		}catch (Exception e) {
			logger.error("error resolving catalogue link",e);
			ExceptionManager.throwInternalErrorException(req, "Error occurred resolving catalogue link", this.getClass(), helpURI);
			return null;
		}
	}

	/**
	 * Post catalogue.
	 *
	 * @param req the req
	 * @param jsonRequest the json request
	 * @return the response
	 */
	@POST
	@Path("")
	@Consumes(MediaType.APPLICATION_JSON)
	@Produces(MediaType.TEXT_PLAIN)
	public Response postCatalogue(@Context HttpServletRequest req, DataMinerRequest jsonRequest) {
		logger.info(this.getClass().getSimpleName()+" POST starts...");

		logger.info("The body contains the request: "+jsonRequest.toString());

		String scope = jsonRequest.getScope();
		String operatorID = jsonRequest.getOperatorId();

		if(scope==null || scope.isEmpty()){
			logger.error("The parameter 'scope' not found or empty in the JSON object");
			ExceptionManager.throwBadRequestException(req, "Mandatory body parameter 'scope' not found or empty in the JSON object", this.getClass(), helpURI);
		}


		if(operatorID==null || operatorID.isEmpty()){
			logger.error("The parameter 'operatorId' not found or empty in the JSON object");
			ExceptionManager.throwBadRequestException(req, "Mandatory body parameter 'operatorId' not found or empty in the JSON object", this.getClass(), helpURI);
		}

		ScopeBean scopeBean = new ScopeBean(scope);

		if(scopeBean.is(Type.VRE)){
			String vreName = scopeBean.name();
			try {
				//CHECK IF IT IS A VALID SCOPE
				LoadingVREsScopeCache.getCache().get(vreName);
				String dataminerResolverURL = String.format("%s/%s",  Util.getServerURL(req), "dataminer");
				String theOperator = "";
				String queryString = "";
				try {
					theOperator = URLEncoder.encode(operatorID, UTF_8);
					Map<String, String> parameters = jsonRequest.getParameters();
					for (String param : parameters.keySet()) {
						String value = parameters.get(param);
						if(value!=null)
							queryString+=String.format(param+"=%s", URLEncoder.encode(parameters.get(param), UTF_8))+"&";
					}
					queryString = Util.removeLastChar(queryString);

				}
				catch (UnsupportedEncodingException e) {
					logger.error("Encoding error: ",e);
					ExceptionManager.throwBadRequestException(req, "Encoding error: "+e.getMessage(), this.getClass(), helpURI);
				}

				String dataMinerURL = String.format("%s/%s/%s?%s", dataminerResolverURL, vreName, theOperator, queryString);
				logger.info("Returning DataMinerURL: "+dataMinerURL);
				return Response.ok(dataMinerURL).header("Location", dataMinerURL).build();

			}
			catch (ExecutionException e) {
				logger.error("The input scope "+scope+" not found", e);
				ExceptionManager.throwBadRequestException(req, "The input 'scope' "+"+scope+"+ "not found on Informatiion System. Is it a valid VRE?", this.getClass(), helpURI);
			}

			return null;

		}else{
			logger.error("The input scope "+scope+" is not a VRE");
			ExceptionManager.throwBadRequestException(req, "The input 'scope' "+"+scope+"+ "is not a VRE", this.getClass(), helpURI);
		}

		return null;
	}

}