package org.gcube.portlets.widgets.ckandatapublisherwidget.server;

import java.util.ArrayList;
import java.util.Calendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import javax.servlet.http.HttpSession;

import org.gcube.application.framework.core.session.ASLSession;
import org.gcube.application.framework.core.session.SessionManager;
import org.gcube.common.homelibrary.home.HomeLibrary;
import org.gcube.common.homelibrary.home.exceptions.InternalErrorException;
import org.gcube.common.homelibrary.home.workspace.Workspace;
import org.gcube.common.homelibrary.home.workspace.WorkspaceItem;
import org.gcube.common.homelibrary.home.workspace.folder.FolderItem;
import org.gcube.common.homelibrary.home.workspace.folder.items.GCubeItem;
import org.gcube.datacatalogue.ckanutillibrary.CKanUtils;
import org.gcube.datacatalogue.ckanutillibrary.CKanUtilsImpl;
import org.gcube.datacatalogue.ckanutillibrary.models.ResourceBean;
import org.gcube.datacatalogue.ckanutillibrary.models.RolesIntoOrganization;
import org.gcube.datacatalogue.metadatadiscovery.DataCalogueMetadataFormatReader;
import org.gcube.datacatalogue.metadatadiscovery.bean.MetadataType;
import org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataField;
import org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataFormat;
import org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataValidator;
import org.gcube.datacatalogue.metadatadiscovery.bean.jaxb.MetadataVocabulary;
import org.gcube.portal.custom.scopemanager.scopehelper.ScopeHelper;
import org.gcube.portlets.widgets.ckandatapublisherwidget.client.CKanPublisherService;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.DatasetMetadataBean;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.LicensesBean;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.MetaDataProfileBean;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.MetaDataTypeWrapper;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.MetadataFieldWrapper;
import org.gcube.portlets.widgets.ckandatapublisherwidget.shared.ResourceBeanWrapper;
import org.gcube.vomanagement.usermanagement.UserManager;
import org.gcube.vomanagement.usermanagement.impl.LiferayUserManager;
import org.gcube.vomanagement.usermanagement.model.GCubeUser;
import org.slf4j.LoggerFactory;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import com.liferay.portal.service.UserLocalServiceUtil;

import eu.trentorise.opendata.jackan.model.CkanLicense;

/**
 * Server side of the data publisher.
 * @author Costantino Perciante at ISTI-CNR (costantino.perciante@isti.cnr.it)
 */
@SuppressWarnings("serial")
public class CKANPublisherServicesImpl extends RemoteServiceServlet implements CKanPublisherService{

	// Logger
	private static final org.slf4j.Logger logger = LoggerFactory.getLogger(CKANPublisherServicesImpl.class);

	public static final String TEST_SCOPE = "/gcube/devsec/devVRE";
	public static final String TEST_USER = "test.user";
	private final static String TEST_SEC_TOKEN = "a1e19695-467f-42b8-966d-bf83dd2382ef";

	// ckan keys for ASL
	private static final String CKAN_TOKEN_KEY = "ckanToken";
	private static final String CKAN_LICENSES_KEY = "ckanLicenses"; // licenses
	private static final String CKAN_ORGANIZATIONS_PUBLISH_KEY = "ckanOrganizationsPublish"; // here he can publish
	private static final String CKAN_PROFILES_KEY = "ckanProfiles"; // product profiles

	/**
	 * Since it needs the scope, we need to check if it is null or not
	 * @return
	 */
	private CKanUtils getCkanUtilsObj(){

		CKanUtils instance = null;

		try{
			String currentScope =  getASLSession().getScope();
			instance = new CKanUtilsImpl(currentScope);
		}catch(Exception e){
			logger.error("Unable to retrieve ckan utils", e);
		}
		return instance;
	}

	/**
	 * the current ASLSession
	 * @return the session
	 */
	private ASLSession getASLSession() {
		String sessionID = this.getThreadLocalRequest().getSession().getId();
		String user = (String) this.getThreadLocalRequest().getSession().getAttribute(ScopeHelper.USERNAME_ATTRIBUTE);

		if (user == null) {
			logger.warn("USER IS NULL setting testing user and Running OUTSIDE PORTAL");
			user = getDevelopmentUser();
			SessionManager.getInstance().getASLSession(sessionID, user).setScope(TEST_SCOPE);
		}		
		return SessionManager.getInstance().getASLSession(sessionID, user);
	}

	/**
	 * when packaging test will fail if the user is not set to test.user
	 * @return .
	 */
	public String getDevelopmentUser() {
		String user = TEST_USER;
		//user = "costantino.perciante";
		return user;
	}

	/**
	 * Get current user's token
	 * @return String the ckan user's token
	 */
	private String getUserCKanTokenFromSession(){

		String token = null;

		if(!isWithinPortal()){
			logger.warn("You are running outside the portal");
			token = TEST_SEC_TOKEN;
		}else{

			ASLSession aslSession = getASLSession();
			String username = aslSession.getUsername();

			// store info in the http session
			HttpSession httpSession = getThreadLocalRequest().getSession();

			// get the key per scope
			String keyPerScope = concatenateSessionKeyScope(CKAN_TOKEN_KEY, aslSession.getScope());

			// check if session expired
			if(username.equals(TEST_USER)){

				logger.warn("Session expired, returning null token");
				token = null;

			}else{
				try{
					logger.debug("User in session is " + username);
					if(httpSession.getAttribute(keyPerScope) != null){
						token = (String)httpSession.getAttribute(keyPerScope);
						logger.debug("Found ckan token into session");
					}
					else{
						token = getCkanUtilsObj().getApiKeyFromUsername(username);
						httpSession.setAttribute(keyPerScope, token);
						logger.debug("Ckan token has been set for user " + username);
					}
					logger.debug("Found ckan token " + token.substring(0, 3) + "************************" + " for user " + username);
				}catch(Exception e){
					logger.error("Error while retrieving the key" , e);
				}
			}
		}
		return token;
	}

	/**
	 * Retrieve the list of organizations in which the user can publish (roles ADMIN, EDITOR)
	 * If he is a SYSADMIN, he can publish everywhere
	 * @param username
	 * @return the list of organizations
	 */
	private List<String> getUserOrganizationsList(String username, String scope) {

		logger.debug("Request for user " + username + " organizations list");
		List<String> orgsName = new ArrayList<String>();
		CKanUtils ckanUtils = getCkanUtilsObj();

		// get http session
		HttpSession httpSession = getThreadLocalRequest().getSession();

		// get key 
		String keyPerScope = concatenateSessionKeyScope(CKAN_ORGANIZATIONS_PUBLISH_KEY, scope);

		if(httpSession.getAttribute(keyPerScope) != null){
			orgsName = (List<String>)httpSession.getAttribute(keyPerScope);
			logger.info("List of organizations was into session");
		}
		else{
			if(getCkanUtilsObj().isSysAdmin(username, getUserCKanTokenFromSession())){

				logger.debug("The user " + username + " is a sysadmin. He can publish everywhere");
				orgsName = ckanUtils.getOrganizationsNames(); // get all organizations' names

			}else{

				// We need to retrieve orgs in which the user has the roles ADMIN or EDITOR
				List<RolesIntoOrganization> rolesToMatch = new ArrayList<RolesIntoOrganization>();
				rolesToMatch.add(RolesIntoOrganization.EDITOR);
				rolesToMatch.add(RolesIntoOrganization.ADMIN);

				Map<String, List<RolesIntoOrganization>> orgsAndRoles = ckanUtils.getGroupsAndRolesByUser(username, rolesToMatch);
				logger.debug("Result is " + orgsAndRoles);
				Iterator<Entry<String, List<RolesIntoOrganization>>> iterator = orgsAndRoles.entrySet().iterator();

				// get the names
				while (iterator.hasNext()) {
					Map.Entry<String, List<RolesIntoOrganization>> entry = (Map.Entry<String, List<RolesIntoOrganization>>) iterator
							.next();
					orgsName.add(entry.getKey());
					logger.debug("The user has a role ADMIN/EDITOR into org "  + entry.getKey());
				}
			}
			httpSession.setAttribute(keyPerScope, orgsName);
			logger.info("Organizations name for user " + username + " has been saved into session");
		}

		return orgsName;
	}

	/**
	 * Online or in development mode?
	 * @return true if you're running into the portal, false if in development
	 */
	private boolean isWithinPortal() {
		try {
			UserLocalServiceUtil.getService();
			return true;
		} 
		catch (com.liferay.portal.kernel.bean.BeanLocatorException ex) {			
			logger.trace("Development Mode ON");
			return false;
		}			
	}

	/**
	 * Find a license id given the license text.
	 * @param chosenLicense
	 * @return
	 */
	private String findLicenseIdByLicense(String chosenLicense) {	
		return getCkanUtilsObj().findLicenseIdByLicense(chosenLicense);
	}

	/**
	 * Retrieve the list of metadata beans
	 * @return
	 */
	private List<MetaDataProfileBean> getMetadataProfilesList() {

		List<MetaDataProfileBean> beans = new ArrayList<MetaDataProfileBean>();

		ASLSession session = getASLSession();
		String username = session.getUsername();
		logger.debug("User in session is " + username);

		// get http session
		HttpSession httpSession = getThreadLocalRequest().getSession();

		// get key per scope
		String keyPerScope = concatenateSessionKeyScope(CKAN_PROFILES_KEY, session.getScope());

		if(httpSession.getAttribute(keyPerScope) != null){
			beans = (List<MetaDataProfileBean>)httpSession.getAttribute(keyPerScope);
			logger.info("List of profiles was into session");
		}
		else{

			try {

				DataCalogueMetadataFormatReader reader = new DataCalogueMetadataFormatReader();

				for (MetadataType mt : reader.getListOfMetadataTypes()) {
					MetadataFormat metadata = reader.getMetadataFormatForMetadataType(mt);

					// we need to wrap the list of metadata
					List<MetadataFieldWrapper> wrapperList = new ArrayList<MetadataFieldWrapper>();
					List<MetadataField> toWrap = metadata.getMetadataFields();
					for(MetadataField metadataField: toWrap){

						MetadataFieldWrapper wrapperObj = new MetadataFieldWrapper();
						wrapperObj.setDefaulValue(metadataField.getDefaulValue());
						wrapperObj.setFieldName(metadataField.getFieldName());
						wrapperObj.setIsBoolean(metadataField.getIsBoolean());
						wrapperObj.setMandatory(metadataField.getMandatory());
						wrapperObj.setNote(metadataField.getNote());

						MetadataValidator validator = metadataField.getValidator();
						if(validator != null)
							wrapperObj.setValidator(validator.getRegularExpression());

						MetadataVocabulary vocabulary = metadataField.getVocabulary();
						if(vocabulary != null)
							wrapperObj.setVocabulary(vocabulary.getVocabularyFields());

						// add to the list
						wrapperList.add(wrapperObj);

					}

					// wrap the mt as well
					MetaDataTypeWrapper typeWrapper = new MetaDataTypeWrapper();
					typeWrapper.setDescription(mt.getDescription());
					typeWrapper.setId(mt.getId());
					typeWrapper.setName(mt.getName());
					MetaDataProfileBean bean = new MetaDataProfileBean(typeWrapper, wrapperList);
					beans.add(bean);
				}

				logger.debug("List of beans is " + beans);
				httpSession.setAttribute(keyPerScope, beans);
				logger.debug("List of profiles has been saved into session");

			} catch (Exception e) {
				logger.error("Error while retrieving metadata beans ", e);
			}
		}

		return beans;
	}

	@Override
	public LicensesBean getLicenses() {

		logger.info("Request for CKAN licenses");

		ASLSession session = getASLSession();
		String username = session.getUsername();
		logger.debug("User in session is " + username);

		// get http session
		HttpSession httpSession = getThreadLocalRequest().getSession();

		// get key per scope
		String keyPerScope = concatenateSessionKeyScope(CKAN_LICENSES_KEY, session.getScope());

		LicensesBean licensesBean = null;
		if(httpSession.getAttribute(keyPerScope) != null){
			licensesBean = (LicensesBean)httpSession.getAttribute(keyPerScope);
			logger.debug("List of licenses was into session");
		}
		else{
			List<CkanLicense> titlesLicenses = getCkanUtilsObj().getLicenses();
			List<String> titles = new ArrayList<String>();
			List<String> urls = new ArrayList<String>();
			for (CkanLicense license : titlesLicenses) {
				titles.add(license.getTitle());
				
				String url = (license.getUrl() != null && !license.getUrl().isEmpty()) ? license.getUrl() : "";
				urls.add(url);
			}
			licensesBean = new LicensesBean(titles, urls);
			httpSession.setAttribute(keyPerScope, licensesBean);
			logger.debug("List of licenses has been saved into session");
		}

		return licensesBean;
	}

	@Override
	public DatasetMetadataBean getDatasetBean(String folderId, String owner){

		DatasetMetadataBean bean = null;

		logger.info("DatasetBean request for " + folderId + " and " + owner);

		ASLSession aslSession = getASLSession();
		String user = aslSession.getUsername();

		if(isWithinPortal()){
			try{

				// check if session expired
				if(user.equals(TEST_USER)){
					logger.debug("SESSION EXPIRED");
					return null;
				}

				logger.debug("Request dataset metadata bean for folder with id " + folderId
						+ " whose owner is " + owner);
				// get usermanager (liferay)
				UserManager liferUserManager = new LiferayUserManager();
				GCubeUser userOwner = liferUserManager.getUserByUsername(owner);

				// build bean
				logger.debug("Building bean");
				bean = new DatasetMetadataBean();

				bean.setId(folderId);
				bean.setOwnerIdentifier(owner);
				bean.setVersion(1);
				bean.setAuthorName(userOwner.getFirstName());
				bean.setAuthorSurname(userOwner.getLastName());
				bean.setAuthorEmail(userOwner.getEmail());
				bean.setMaintainer(userOwner.getFullname());
				bean.setMaintainerEmail(userOwner.getEmail());
				bean.setOrganizationList(getUserOrganizationsList(owner, aslSession.getScope()));

				// if the request comes from the workspace
				if(folderId != null && !folderId.isEmpty()){

					Workspace ws = HomeLibrary
							.getHomeManagerFactory()
							.getHomeManager()
							.getHome(owner).getWorkspace();

					WorkspaceItem retrievedItem = ws.getItem(folderId);

					// set some info
					String onlyAlphanumeric = retrievedItem.getName().replaceAll("[^A-Za-z0-9]", "");
					bean.setTitle(onlyAlphanumeric);
					bean.setDescription(retrievedItem.getDescription());

					// retrieve gcube items of the folder
					Map<String, String> folderItems = getGcubeItemProperties(retrievedItem);
					bean.setCustomFields(folderItems);

					// check the resources within the folder (skip subdirectories)
					List<String> childrenIds = new ArrayList<String>();

					for (WorkspaceItem file : retrievedItem.getChildren()) {
						if(!file.isFolder()) // ok, it's a file
							childrenIds.add(file.getId());
					}

					List<ResourceBeanWrapper> listOfResources = getWorkspaceResourcesInformation(childrenIds, ws, user);
					bean.setResources(listOfResources);
				}

				// retrieve the metadata
				List<MetaDataProfileBean> metadataBeans = getMetadataProfilesList();
				bean.setMetadataList(metadataBeans);

			}catch(Exception e){
				logger.error("Error while retrieving folder information", e);
			}
		}else{

			try{

				bean = new DatasetMetadataBean();
				bean.setId(folderId);
				bean.setDescription("This is a fantastic description");
				bean.setVersion(1);
				String onlyAlphanumeric = "test-creation-blablabla".replaceAll("[^A-Za-z0-9]", "");
				bean.setTitle(onlyAlphanumeric + Calendar.getInstance().getTimeInMillis());
				bean.setAuthorName("Costantino");
				bean.setAuthorSurname("Perciante");
				bean.setAuthorEmail("costantino.perciante@isti.cnr.it");
				bean.setMaintainer("Costantino Perciante");
				bean.setMaintainerEmail("costantino.perciante@isti.cnr.it");
				bean.setOrganizationList(getUserOrganizationsList(owner, TEST_SCOPE));
				bean.setOwnerIdentifier(owner);

				if(folderId != null && !folderId.isEmpty()){

					Workspace ws = HomeLibrary
							.getHomeManagerFactory()
							.getHomeManager()
							.getHome(owner).getWorkspace();

					WorkspaceItem retrievedItem = ws.getItem(folderId);

					// retrieve gcube items of the folder
					Map<String, String> folderItems = getGcubeItemProperties(retrievedItem);
					bean.setCustomFields(folderItems);

					// check the resources within the folder (skip subdirectories)
					List<String> childrenIds = new ArrayList<String>();

					for (WorkspaceItem file : retrievedItem.getChildren()) {
						if(!file.isFolder()) // ok, it's a file
							childrenIds.add(file.getId());
					}
					List<ResourceBeanWrapper> listOfResources = getWorkspaceResourcesInformation(childrenIds, ws, user);
					bean.setResources(listOfResources);
				}

				// retrieve the metadata
				List<MetaDataProfileBean> metadataBeans = getMetadataProfilesList();
				bean.setMetadataList(metadataBeans);

			}catch(Exception e){
				logger.error("Error while building bean into dev mode", e);
			}
		}

		return bean;
	}

	/** Gets the gcube item properties.
	 *
	 * @param item the item
	 * @return the gcube item properties
	 */
	private Map<String, String> getGcubeItemProperties(WorkspaceItem item) {

		if(item instanceof GCubeItem){
			GCubeItem gItem = (GCubeItem) item;
			try {
				if(gItem.getProperties()!=null){
					Map<String, String> map = gItem.getProperties().getProperties();
					HashMap<String, String> properties = new HashMap<String, String>(map.size()); //TO PREVENT GWT SERIALIZATION ERROR
					for (String key : map.keySet())
						properties.put(key, map.get(key));

					return properties;
				}
			} catch (InternalErrorException e) {
				logger.error("Error in server getItemProperties: ", e);
				return null;
			}
		}
		return null;
	}

	@Override
	public DatasetMetadataBean createCKanDataset(DatasetMetadataBean toCreate, boolean isWorkspaceRequest) {

		logger.debug("Request for creating a dataset with these information " + toCreate);

		ASLSession aslSession = getASLSession();
		String user = aslSession.getUsername();
		CKanUtils utils = getCkanUtilsObj();

		try{

			// check if session expired
			if(user.equals(TEST_USER)){
				logger.debug("SESSION EXPIRED");
				return null;
			}

			String title = toCreate.getTitle();
			String organizationNameOrId = toCreate.getSelectedOrganization();
			String author = toCreate.getAuthorFullName();
			String authorMail = toCreate.getAuthorEmail();
			String maintainer = toCreate.getMaintainer();
			String maintainerMail = toCreate.getMaintainerEmail();
			long version = toCreate.getVersion();
			String description = toCreate.getDescription();
			String chosenLicense = toCreate.getLicense();
			String licenseId = findLicenseIdByLicense(chosenLicense);
			List<String> listOfTags = toCreate.getTags();
			Map<String, String> customFields = toCreate.getCustomFields();
			boolean setPublic = toCreate.getVisibility();

			// get the list of resources and convert to ResourceBean
			List<ResourceBean> resources = new ArrayList<ResourceBean>();
			List<ResourceBeanWrapper> resourcesToAdd = toCreate.getResources();

			if(resourcesToAdd != null && !resourcesToAdd.isEmpty())
				for (ResourceBeanWrapper resourceBeanWrapper : resourcesToAdd) {

					if(resourceBeanWrapper.isToBeAdded()){
						resources.add(new ResourceBean(
								resourceBeanWrapper.getUrl(), 
								resourceBeanWrapper.getName(), 
								resourceBeanWrapper.getDescription(), 
								resourceBeanWrapper.getId(),
								resourceBeanWrapper.getOwner(), 
								null, 
								resourceBeanWrapper.getMimeType()));

					}

				}

			String datasetId = utils.createCKanDataset(getUserCKanTokenFromSession(), title, organizationNameOrId,  author,
					authorMail,  maintainer,  maintainerMail,  version, description, licenseId,
					listOfTags, customFields, resources, setPublic);

			if(datasetId != null){

				logger.debug("Dataset created!");
				toCreate.setId(datasetId);

				// retrieve the url
				String datasetUrl =  utils.getPortletUrl() + "?path=" +  utils.getUrlFromDatasetIdOrName(getUserCKanTokenFromSession(), datasetId, true);

				toCreate.setSource(datasetUrl);
				return toCreate;

			}else{

				logger.error("Failed to create the dataset");

			}

		}catch(Exception e){
			logger.error("Unable to create the dataset", e);
		}

		return null;
	}

	@Override
	public ResourceBeanWrapper addResourceToDataset(ResourceBeanWrapper resource, String datasetId, String owner) {

		logger.debug("Incoming request for creating new resource for dataset with id " + datasetId);
		logger.debug("Owner is " + owner + " and resource is " + resource);

		if(!isWithinPortal()){

			logger.warn("Running outside the portal");
			return resource;

		}else{

			ASLSession session = getASLSession();
			String username = session.getUsername();

			if(username.equals(TEST_USER)){

				logger.warn("SESSION EXPIRED! ");
				return null;

			}else{

				try{

					ResourceBean resourceBean = new ResourceBean(
							resource.getUrl(), 
							resource.getName(), 
							resource.getDescription(), 
							null, 
							owner, 
							datasetId,
							null);

					String resourceId = getCkanUtilsObj().addResourceToDataset(resourceBean, getUserCKanTokenFromSession());

					if(resourceId != null){
						logger.debug("Resource  " + resource.getName() + " is now available");
						// set its id and turn it to the client
						resource.setId(resourceId);
						return resource;
					}
				}catch(Exception e){
					logger.error("Unable to create new resource", e);
				}
			}
			logger.debug("No resource created");
			return null;
		}
	}

	@Override
	public boolean deleteResourceFromDataset(ResourceBeanWrapper resource,
			String owner) {

		logger.debug("Request for deleting resource " + resource);
		boolean deleted = false;

		if(!isWithinPortal()){
			logger.warn("Running outside the portal");
			return deleted;
		}else{

			ASLSession session = getASLSession();
			String username = session.getUsername();

			if(username.equals(TEST_USER)){
				logger.warn("SESSION EXPIRED! ");
				return deleted;
			}else{
				try{
					deleted = getCkanUtilsObj().
							deleteResourceFromDataset(resource.getId(), getUserCKanTokenFromSession());
					if(deleted){
						logger.debug("Resource described by " + resource + " deleted");
					}else
						logger.error("Resource described by " + resource + " NOT deleted");
				}catch(Exception e){
					logger.error("Error while trying to delete resource described by " + resource, e);
				}
				return deleted;
			}
		}
	}

	/**
	 * Builds a string made of key + scope
	 * @param key
	 * @param scope
	 * @return
	 */
	private String concatenateSessionKeyScope(String key, String scope){
		return key.concat(scope);
	}

	/**
	 * Build up the resource beans.
	 * @param resourceIds
	 * @param ws
	 * @param username
	 * @return
	 */
	private List<ResourceBeanWrapper> getWorkspaceResourcesInformation(
			List<String> resourceIds, Workspace ws, String username) {

		List<ResourceBeanWrapper> toReturn = null;

		try{

			toReturn = new ArrayList<>();

			for (String resourceId : resourceIds) {

				logger.debug("RESOURCE ID IS " + resourceId);

				ResourceBeanWrapper newResource = new ResourceBeanWrapper();
				WorkspaceItem item = ws.getItem(resourceId);
				newResource.setDescription(item.getDescription());
				newResource.setId(item.getId());
				newResource.setUrl(item.getPublicLink(true));
				newResource.setName(item.getName());
				newResource.setToBeAdded(true); // default is true
				newResource.setMimeType(((FolderItem)item).getMimeType());
				newResource.setOwner(username);
				toReturn.add(newResource);

			}
		}catch(Exception e){
			logger.error("Unable to retrieve resources' info", e);
		}

		return toReturn;
	}
}