package org.gcube.datatransfer.resolver.services;

import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.stream.Collectors;

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.QueryParam;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.gcube.common.scope.api.ScopeProvider;
import org.gcube.common.scope.impl.ScopeBean;
import org.gcube.datatransfer.resolver.ConstantsResolver;
import org.gcube.datatransfer.resolver.caches.LoadingMapOfScopeCache;
import org.gcube.datatransfer.resolver.geoportal.GeoportalCommonConstants;
import org.gcube.datatransfer.resolver.geoportal.GeoportalDataViewerConfigProfile;
import org.gcube.datatransfer.resolver.geoportal.GeoportalDataViewerConfigProfileReader;
import org.gcube.datatransfer.resolver.geoportal.GeoportalRequest;
import org.gcube.datatransfer.resolver.geoportal.TargetAppGeoportalCodes;
import org.gcube.datatransfer.resolver.services.error.ExceptionManager;
import org.gcube.datatransfer.resolver.util.Util;
import org.gcube.smartgears.utils.InnerMethodName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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

/**
 * The GeoportalResolver is able to get/resolve a link to "Geoportal Viewer" or
 * "Geoportal Entry" Application.
 * 
 * See more at
 * https://gcube.wiki.gcube-system.org/gcube/URI_Resolver#Geoportal_Resolver
 *
 * @author Francesco Mangiacrapa at ISTI-CNR francesco.mangiacrapa@isti.cnr.it
 * 
 *         Mar 23, 2023
 */
@Path("/geo")
public class GeoportalResolver {

	public static final String GEO_DE = "de"; // data-entry
	public static final String GEO = "geo"; // geoportal
	public static final String GEO_DV = "dv"; // data-viewer

	private static final String QP_RESOLVE_AS = "res";
	private static final String PATH_PROJECT_ID = "project_id";
	private static final String PATH_USECASE_ID = "usecase_id";
	private static final String PATH_VRE_NAME = "vre_name";
	private static final String PATH_TARGET_APP = "targetAppId";

	private static final Logger LOG = LoggerFactory.getLogger(GeoportalResolver.class);
	private static String helpURI = "https://wiki.gcube-system.org/gcube/URI_Resolver#Geoportal_Resolver";

	/**
	 * The Enum RESOLVE_AS_PARAMETER.
	 *
	 * @author Francesco Mangiacrapa at ISTI-CNR francesco.mangiacrapa@isti.cnr.it
	 * 
	 *         Mar 24, 2023
	 */
	private static enum RESOLVE_AS {
		PUBLIC, PRIVATE
	}

	/**
	 * Resolve geoportal. Resolve a Geoportal Link to "Data-Viewer" App
	 *
	 * @param req       the req
	 * @param vreName   the vre name
	 * @param ucdID     the ucd ID
	 * @param projectID the project ID
	 * @param resolveAs the resolve as
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@GET
	@Path("/{vre_name}/{usecase_id}/{project_id}")
	public Response resolveGeoportalNoAppDef(@Context HttpServletRequest req, @PathParam(PATH_VRE_NAME) String vreName,
			@PathParam(PATH_USECASE_ID) String ucdID, @PathParam(PATH_PROJECT_ID) String projectID,
			@QueryParam(QP_RESOLVE_AS) String resolveAs) throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " resolveGeoportalNoAppDef - GET starts...");
		TargetAppGeoportalCodes targetAppGeoportalCodes = checkTargetApplictionID(req, null);
		LOG.info("The target app is: " + targetAppGeoportalCodes);
		return genericResolveLink(req, targetAppGeoportalCodes, vreName, ucdID, projectID, resolveAs);

	}

	/**
	 * Resolve geoportal. Resolve a Geoportal Link to "Data-Viewer" or "Data-Entry"
	 * App
	 *
	 * @param req         the req
	 * @param targetAppId the target app id
	 * @param vreName     the vre name
	 * @param ucdID       the ucd ID
	 * @param projectID   the project ID
	 * @param resolveAs   the resolve as
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@GET
	@Path("/{targetAppId}/{vre_name}/{usecase_id}/{project_id}")
	public Response resolveGeoportal(@Context HttpServletRequest req, @PathParam(PATH_TARGET_APP) String targetAppId,
			@PathParam(PATH_VRE_NAME) String vreName, @PathParam(PATH_USECASE_ID) String ucdID,
			@PathParam(PATH_PROJECT_ID) String projectID, @QueryParam(QP_RESOLVE_AS) String resolveAs)
			throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " resolveGeoportal - GET starts...");
		TargetAppGeoportalCodes targetAppGeoportalCodes = checkTargetApplictionID(req, targetAppId);
		LOG.info("The target app is: " + targetAppGeoportalCodes);
		return genericResolveLink(req, targetAppGeoportalCodes, vreName, ucdID, projectID, resolveAs);

	}

	/**
	 * Resolve data viewer link.
	 *
	 * @param req        the req
	 * @param gcubeScope the gcube scope
	 * @param itemId     the item id
	 * @param itemType   the item type
	 * @param resolveAs  the resolve as
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@GET
	@Path("/")
	public Response resolveDataViewerLink(@Context HttpServletRequest req,
			@QueryParam(GeoportalRequest.P_GCUBE_SCOPE) String gcubeScope,
			@QueryParam(GeoportalRequest.P_ITEM_ID) String itemId,
			@QueryParam(GeoportalRequest.P_ITEM_TYPE) String itemType, 
			@QueryParam(QP_RESOLVE_AS) String resolveAs)
			throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " resolveDataViewerLink - GET starts...");
		TargetAppGeoportalCodes targetAppGeoportalCodes = checkTargetApplictionID(req, null);
		LOG.info("The target app is: " + targetAppGeoportalCodes);

		if (gcubeScope == null || gcubeScope.isEmpty()) {

			LOG.error("The query parameter '" + GeoportalRequest.P_GCUBE_SCOPE + "' not found or empty");
			throw ExceptionManager.badRequestException(req,
					"Mandatory query parameter '" + GeoportalRequest.P_GCUBE_SCOPE + "' not found or empty",
					this.getClass(), helpURI);

		}

		String scope = gcubeScope.substring(gcubeScope.lastIndexOf("/") + 1, gcubeScope.length());
		return genericResolveLink(req, targetAppGeoportalCodes, scope, itemType, itemId, resolveAs);

	}

	/**
	 * Post geoportal. Create a Geoportal Link to "Data-Viewer" App
	 *
	 * @param req         the req
	 * @param jsonRequest the json request
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@POST
	@Path("")
	@Consumes(MediaType.APPLICATION_JSON)
	@Produces(MediaType.TEXT_PLAIN)
	public Response postGeoportalNoAppDef(@Context HttpServletRequest req, GeoportalRequest jsonRequest)
			throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " postGeoportalNoAppDef - POST starts...");
		TargetAppGeoportalCodes targetAppGeoportalCodes = checkTargetApplictionID(req, null);
		LOG.info("The target app is: " + targetAppGeoportalCodes);
		String linkURL = genericCreateLink(req, jsonRequest, targetAppGeoportalCodes);
		return Response.ok(linkURL).header("Location", linkURL).build();
	}

	/**
	 * Post geoportal. Create a Geoportal Link to "Data-Viewer" or "Data-Entry" App
	 *
	 * @param req         the req
	 * @param targetAppId the target app id
	 * @param jsonRequest the json request
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	@POST
	@Path("/{targetAppId}")
	@Consumes(MediaType.APPLICATION_JSON)
	@Produces(MediaType.TEXT_PLAIN)
	public Response postGeoportal(@Context HttpServletRequest req, @PathParam(PATH_TARGET_APP) String targetAppId,
			GeoportalRequest jsonRequest) throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " postGeoportal - POST starts...");
		TargetAppGeoportalCodes targetAppGeoportalCodes = checkTargetApplictionID(req, targetAppId);
		LOG.info("The target app is: " + targetAppGeoportalCodes);
		String linkURL = genericCreateLink(req, jsonRequest, targetAppGeoportalCodes);
		return Response.ok(linkURL).header("Location", linkURL).build();
	}

	/**
	 * Check target appliction ID.
	 *
	 * @param req         the req
	 * @param targetAppId the target app id
	 * @return the target app geoportal codes
	 */
	private TargetAppGeoportalCodes checkTargetApplictionID(@Context HttpServletRequest req, String targetAppId) {

		TargetAppGeoportalCodes targetAppGeoportalCodes = null;

		if (targetAppId == null) {
			targetAppGeoportalCodes = TargetAppGeoportalCodes.GEO_DV;
			LOG.warn("Target application parameter is null, using default: " + targetAppGeoportalCodes);
		} else {

			// IF the target application passed in the request. It must be proper.
			targetAppGeoportalCodes = TargetAppGeoportalCodes.valueOfId(targetAppId);

			if (targetAppGeoportalCodes == null) {
				LOG.error("Target application parameter is malformed");
				List<String> targetApps = Arrays.asList(TargetAppGeoportalCodes.values()).stream()
						.map(TargetAppGeoportalCodes::getTarget_app).collect(Collectors.toList());
				throw ExceptionManager.badRequestException(req,
						"Target application is wrong. It must be one value of: " + targetApps, this.getClass(),
						helpURI);
			}
		}

		return targetAppGeoportalCodes;

	}

	/**
	 * Generic resolve link.
	 *
	 * @param req                    the req
	 * @param resoruceGeoportalCodes the resoruce geoportal codes
	 * @param vreName                the vre name
	 * @param ucdID                  the ucd ID
	 * @param projectID              the project ID
	 * @param resolveAs              the resolve as
	 * @return the response
	 * @throws WebApplicationException the web application exception
	 */
	public Response genericResolveLink(@Context HttpServletRequest req, TargetAppGeoportalCodes resoruceGeoportalCodes,
			@PathParam(PATH_VRE_NAME) String vreName, @PathParam(PATH_USECASE_ID) String ucdID,
			@PathParam(PATH_PROJECT_ID) String projectID, @QueryParam(QP_RESOLVE_AS) String resolveAs)
			throws WebApplicationException {

		LOG.info(this.getClass().getSimpleName() + " genericResolveLink starts...");

		try {
			InnerMethodName.instance.set("resolveGeoportalPublicLink");

			LOG.info("Found target app: " + resoruceGeoportalCodes);

			if (resoruceGeoportalCodes == null) {
				LOG.error("The path parameter '" + PATH_TARGET_APP + "' not found or empty in the path");
				throw ExceptionManager.badRequestException(req,
						"Mandatory path parameter '" + PATH_TARGET_APP + "' not found or empty", this.getClass(),
						helpURI);
			}

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

			if (ucdID == null) {
				LOG.error("The path parameter '" + PATH_USECASE_ID + "' not found or empty in the path");
				throw ExceptionManager.badRequestException(req,
						"Mandatory path parameter '" + PATH_USECASE_ID + "' not found or empty", this.getClass(),
						helpURI);
			}

			if (projectID == null) {
				LOG.error("The path parameter '" + PATH_PROJECT_ID + "' not found or empty in the path");
				throw ExceptionManager.badRequestException(req,
						"Mandatory path parameter '" + PATH_PROJECT_ID + "' 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) {
				LOG.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);
			}

			RESOLVE_AS resolveTO = RESOLVE_AS.PUBLIC;
			if (resolveAs != null) {
				switch (resolveAs.toLowerCase()) {
				case "public":
					resolveTO = RESOLVE_AS.PUBLIC;
					break;
				case "private":
					resolveTO = RESOLVE_AS.PRIVATE;
					break;
				}
			}

			LOG.info("Found RESOLVE_AS_PARAMETER: " + resolveAs);

			String originalScope = ScopeProvider.instance.get();
			GeoportalDataViewerConfigProfileReader reader;
			try {
				String theScope = fullScopeBean.toString();
				LOG.info("Full scope is: " + theScope);
				ScopeProvider.instance.set(theScope);
				reader = new GeoportalDataViewerConfigProfileReader(
						org.gcube.datatransfer.resolver.geoportal.GeoportalCommonConstants.GEOPORTAL_DATA_VIEWER_APP);
			} catch (Exception e) {
				LOG.error("Error on reading the " + GeoportalDataViewerConfigProfileReader.SECONDARY_TYPE
						+ " with generic resource name: "
						+ GeoportalDataViewerConfigProfileReader.GENERIC_RESOURCE_NAME, e);
				throw ExceptionManager.internalErrorException(req,
						"Error on reading the " + GeoportalDataViewerConfigProfileReader.SECONDARY_TYPE + " for name "
								+ GeoportalDataViewerConfigProfileReader.GENERIC_RESOURCE_NAME
								+ ". Please contact the support",
						this.getClass(), helpURI);
			} finally {
				if (originalScope != null && !originalScope.isEmpty()) {
					ScopeProvider.instance.set(originalScope);
					LOG.info("scope provider set to orginal scope: " + originalScope);
				} else {
					ScopeProvider.instance.reset();
					LOG.info("scope provider reset");
				}
			}

			// Resolving towards Data-Viewer or Data-Entry Application
			String itemLink = null;

			switch (resoruceGeoportalCodes) {
			case GEO_DV: {

				GeoportalDataViewerConfigProfile geonaDataProfile = reader.getGeoportalDataViewerConfigProfile();

				switch (resolveTO) {
				case PUBLIC:
					// Open Link
					itemLink = String.format("%s?%s=%s&%s=%s", geonaDataProfile.getOpenPortletURL(),
							GeoportalCommonConstants.GET_GEONA_ITEM_ID, projectID,
							GeoportalCommonConstants.GET_GEONA_ITEM_TYPE, ucdID);
					break;
				case PRIVATE:

					// Restricted Link
					itemLink = String.format("%s?%s=%s&%s=%s", geonaDataProfile.getRestrictedPortletURL(),
							GeoportalCommonConstants.GET_GEONA_ITEM_ID, projectID,
							GeoportalCommonConstants.GET_GEONA_ITEM_TYPE, ucdID);

					break;

				default:
					break;
				}

				break;
			}

			case GEO_DE: {

				LOG.error("The Resolver towards '" + resoruceGeoportalCodes + "' not implemented yet");
				throw ExceptionManager.internalErrorException(req,
						"The Resolver towards '" + resoruceGeoportalCodes + "' not implemented yet", this.getClass(),
						helpURI);

			}
			default:
				break;
			}

			LOG.info("Returning link: " + itemLink);
			return Response.seeOther(new URL(itemLink).toURI()).build();
		} catch (Exception e) {

			if (!(e instanceof WebApplicationException)) {
				// UNEXPECTED EXCEPTION managing it as WebApplicationException
				String error = "Error occurred on resolving the " + GeoportalResolver.class.getSimpleName()
						+ " 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
			LOG.error("Exception:", e);
			throw (WebApplicationException) e;
		}
	}

	/**
	 * Generic create link.
	 *
	 * @param req                     the req
	 * @param jsonRequest             the json request
	 * @param targetAppGeoportalCodes the target app geoportal codes
	 * @return the URL
	 */
	protected String genericCreateLink(@Context HttpServletRequest req, GeoportalRequest jsonRequest,
			TargetAppGeoportalCodes targetAppGeoportalCodes) {

		LOG.info(this.getClass().getSimpleName() + " genericCreateLink starts...");

		try {

			InnerMethodName.instance.set("postGeoportalPublicLink");
			LOG.info("The body contains the request: " + jsonRequest.toString());

			if (jsonRequest.getGcubeScope() == null) {
				throw ExceptionManager.badRequestException(req, "Missing parameter " + GeoportalRequest.P_GCUBE_SCOPE,
						this.getClass(), helpURI);
			}

			if (jsonRequest.getItemID() == null) {
				throw ExceptionManager.badRequestException(req, "Missing parameter " + GeoportalRequest.P_ITEM_ID,
						this.getClass(), helpURI);
			}

			if (jsonRequest.getItemType() == null) {
				throw ExceptionManager.badRequestException(req, "Missing parameter " + GeoportalRequest.P_ITEM_TYPE,
						this.getClass(), helpURI);
			}

			// CHECK IF INPUT SCOPE IS VALID
			String scope = jsonRequest.getGcubeScope();
			if (!scope.startsWith(ConstantsResolver.SCOPE_SEPARATOR)) {
				LOG.info("Scope not start with char '{}' adding it", ConstantsResolver.SCOPE_SEPARATOR);
				scope += ConstantsResolver.SCOPE_SEPARATOR + scope;
			}

			String serverUrl = Util.getServerURL(req);
			final String vreName = scope.substring(scope.lastIndexOf(ConstantsResolver.SCOPE_SEPARATOR) + 1,
					scope.length());
			ScopeBean fullScope = null;

			// CHECK IF THE vreName has a valid scope, so it is a valid VRE
			try {
				fullScope = LoadingMapOfScopeCache.get(vreName);
			} catch (ExecutionException e) {
				LOG.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);
			}

			if (fullScope == null)
				throw ExceptionManager.notFoundException(req,
						"The scope '" + scope + "' does not matching any scope in the infrastructure. Is it valid?",
						this.getClass(), helpURI);

			String linkURL = String.format("%s/%s/%s/%s/%s/%s", serverUrl, GEO, targetAppGeoportalCodes.getId(),
					vreName, jsonRequest.getItemType(), jsonRequest.getItemID());

			if (jsonRequest.getQueryString() != null) {
				linkURL += "?" + jsonRequest.getQueryString();
			}

			LOG.info("Returning " + GeoportalResolver.class.getSimpleName() + " URL: " + linkURL);
			return linkURL;

		} catch (Exception e) {

			if (!(e instanceof WebApplicationException)) {
				// UNEXPECTED EXCEPTION managing it as WebApplicationException
				String error = "Error occurred on creating the " + GeoportalResolver.class.getSimpleName()
						+ " URL. Please, contact the support!";
				throw ExceptionManager.internalErrorException(req, error, this.getClass(), helpURI);
			}
			// ALREADY MANAGED AS WebApplicationExceptiongetItemCatalogueURLs
			LOG.error("Exception:", e);
			throw (WebApplicationException) e;
		}

	}

}