package org.gcube.data.access.storagehub.services;

import java.util.Collections;
import java.util.List;

import javax.enterprise.context.RequestScoped;
import javax.inject.Inject;
import javax.jcr.Node;
import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.servlet.ServletContext;
import javax.ws.rs.Consumes;
import javax.ws.rs.DELETE;
import javax.ws.rs.FormParam;
import javax.ws.rs.GET;
import javax.ws.rs.PUT;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.apache.jackrabbit.api.JackrabbitSession;
import org.gcube.common.gxrest.response.outbound.GXOutboundErrorResponse;
import org.gcube.common.storagehub.model.Excludes;
import org.gcube.common.storagehub.model.Paths;
import org.gcube.common.storagehub.model.exceptions.BackendGenericError;
import org.gcube.common.storagehub.model.exceptions.InvalidCallParameters;
import org.gcube.common.storagehub.model.exceptions.InvalidItemException;
import org.gcube.common.storagehub.model.exceptions.StorageHubException;
import org.gcube.common.storagehub.model.exceptions.UserNotAuthorizedException;
import org.gcube.common.storagehub.model.items.FolderItem;
import org.gcube.common.storagehub.model.items.Item;
import org.gcube.common.storagehub.model.items.TrashItem;
import org.gcube.common.storagehub.model.service.ItemList;
import org.gcube.common.storagehub.model.service.ItemWrapper;
import org.gcube.data.access.storagehub.AuthorizationChecker;
import org.gcube.data.access.storagehub.Constants;
import org.gcube.data.access.storagehub.PathUtil;
import org.gcube.data.access.storagehub.Range;
import org.gcube.data.access.storagehub.StorageHubAppllicationManager;
import org.gcube.data.access.storagehub.Utils;
import org.gcube.data.access.storagehub.handlers.CredentialHandler;
import org.gcube.data.access.storagehub.handlers.TrashHandler;
import org.gcube.data.access.storagehub.handlers.items.Item2NodeConverter;
import org.gcube.data.access.storagehub.handlers.items.Node2ItemConverter;
import org.gcube.data.access.storagehub.handlers.items.builders.FolderCreationParameters;
import org.gcube.data.access.storagehub.handlers.plugins.FolderPluginHandler;
import org.gcube.data.access.storagehub.handlers.vres.VRE;
import org.gcube.data.access.storagehub.handlers.vres.VREManager;
import org.gcube.data.access.storagehub.query.sql2.evaluators.Evaluators;
import org.gcube.smartgears.annotations.ManagedBy;
import org.gcube.smartgears.utils.InnerMethodName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.webcohesion.enunciate.metadata.rs.RequestHeader;
import com.webcohesion.enunciate.metadata.rs.RequestHeaders;



@Path("/")
@ManagedBy(StorageHubAppllicationManager.class)
@RequestHeaders({
	  @RequestHeader( name = "Authorization", description = "Bearer token, see https://dev.d4science.org/how-to-access-resources"),
	})
public class WorkspaceManager extends Impersonable{

	private static final Logger log = LoggerFactory.getLogger(WorkspaceManager.class);

	RepositoryInitializer repository = StorageHubAppllicationManager.repository;
	
	@Inject
	Evaluators evaluator;

	@Inject
	PathUtil pathUtil;
	
	@Inject
	VREManager vreManager;
	
	@Context 
	ServletContext context;

	@Inject
	AuthorizationChecker authChecker;
	
	@Inject
	TrashHandler trashHandler;
	
	@RequestScoped
	@QueryParam("exclude") 
	private List<String> excludes = Collections.emptyList();
	
	@Inject Node2ItemConverter node2Item;
	@Inject Item2NodeConverter item2Node;

	@Inject
	FolderPluginHandler folderHandler;
		
	
	@Path("/")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemWrapper<Item> getWorkspace(@QueryParam("relPath") String relPath){
		InnerMethodName.instance.set("getWorkspace");
		Session ses = null;
		org.gcube.common.storagehub.model.Path absolutePath;
		if (relPath==null)
			absolutePath = pathUtil.getWorkspacePath(currentUser);
		else absolutePath = Paths.append(pathUtil.getWorkspacePath(currentUser), relPath);

		Item toReturn = null;
		try{
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			//TODO: remove when all user will have TRASH
			org.gcube.common.storagehub.model.Path trashPath = pathUtil.getTrashPath(currentUser, ses);
			if (!ses.nodeExists(trashPath.toPath())) {
				Node wsNode = ses.getNode(pathUtil.getWorkspacePath(currentUser).toPath());
				FolderCreationParameters trashFolderParameters = FolderCreationParameters.builder().name(Constants.TRASH_ROOT_FOLDER_NAME)
						.description("trash of "+currentUser)
						.author(currentUser).on(wsNode.getIdentifier()).with(ses).build();
				Utils.createFolderInternally(trashFolderParameters, null);
				ses.save();
			}
			Node node = ses.getNode(absolutePath.toPath());
			authChecker.checkReadAuthorizationControl(ses, currentUser, node.getIdentifier());
			toReturn = node2Item.getItem(node, excludes);
		}catch(RepositoryException re ){
			log.error("jcr error getting workspace item", re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}

		return new ItemWrapper<Item>(toReturn);
	}

	
	@Path("vrefolder")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemWrapper<Item> getVreRootFolder(){
		InnerMethodName.instance.set("getVreRootFolder");
		JackrabbitSession ses = null;
		Item vreItem = null;
		try {
			ses = (JackrabbitSession) repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			vreItem = vreManager.getVreFolderItem(ses, currentUser, excludes).getVreFolder();
		}catch(RepositoryException re ){
			log.error("jcr error getting vrefolder", re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}
		return new ItemWrapper<Item>(vreItem);
	}

	@Path("vrefolder/recents")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemList getVreFolderRecentsDocument(){
		InnerMethodName.instance.set("getVreFolderRecents");
		JackrabbitSession ses = null;
		List<Item> recentItems = Collections.emptyList();
		try{
			ses =  (JackrabbitSession) repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			
			VRE vre = vreManager.getVreFolderItem(ses, currentUser, excludes);
			log.trace("VRE retrieved {}",vre.getVreFolder().getTitle());
			recentItems = vre.getRecents();
			log.trace("recents retrieved {}",vre.getVreFolder().getTitle());
			return new ItemList(recentItems);
		}catch(RepositoryException re ){
			log.error("jcr error getting recents", re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}

		return new ItemList(recentItems);

		
	}


	@Path("trash")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemWrapper<Item> getTrashRootFolder(){
		InnerMethodName.instance.set("getTrashRootFolder");
		Session ses = null;
		
		Item item = null;
		try{
			long start = System.currentTimeMillis();
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			org.gcube.common.storagehub.model.Path trashPath = pathUtil.getTrashPath(currentUser, ses);
			log.info("time to connect to repo  {}",(System.currentTimeMillis()-start));
			
			Node folder = ses.getNode(trashPath.toPath());
			item = node2Item.getItem(folder, excludes);
		}catch(RepositoryException re ){
			log.error("jcr error getting trash", re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}
		
		return new ItemWrapper<Item>(item);
	}
	
		
	@Path("trash/empty")
	@DELETE
	public String emptyTrash(){
		InnerMethodName.instance.set("emptyTrash");
		Session ses = null;
		String toReturn = null;
		try{
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			org.gcube.common.storagehub.model.Path trashPath = pathUtil.getTrashPath(currentUser, ses);
			Node trashNode = ses.getNode(trashPath.toPath());
			List<Item> itemsToDelete = Utils.getItemList(trashNode, Excludes.ALL, null, true, null);
			trashHandler.removeNodes(ses, itemsToDelete);
			toReturn = trashNode.getIdentifier();
		}catch(RepositoryException re ){
			log.error("jcr error emptying trash", re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}
		
		return toReturn;
	}
	
	@PUT
	@Consumes(MediaType.APPLICATION_FORM_URLENCODED)
	@Path("trash/restore")
	public String restoreItem(@FormParam("trashedItemId") String trashedItemId,@FormParam("destinationId") String destinationFolderId){
		InnerMethodName.instance.set("restoreItem");
		Session ses = null;
		String toReturn = null;
		try{

			log.info("restoring node with id {}", trashedItemId);
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));

			final Node nodeToRestore = ses.getNodeByIdentifier(trashedItemId);

			Item itemToRestore = node2Item.getItem(nodeToRestore, Excludes.ALL);
			
			if (!(itemToRestore instanceof TrashItem))
				throw new InvalidItemException("Only trash items can be restored");
			
			org.gcube.common.storagehub.model.Path trashPath = pathUtil.getTrashPath(currentUser, ses);
			if (!itemToRestore.getPath().startsWith(trashPath.toPath()))
				throw new UserNotAuthorizedException("this item is not in the user "+currentUser+" trash");

			Item destinationItem = null;
			if (destinationFolderId!=null ) {
				destinationItem = node2Item.getItem(ses.getNodeByIdentifier(destinationFolderId), Excludes.ALL);
				if (!(destinationItem instanceof FolderItem)) 
					throw new InvalidCallParameters("destintation item is not a folder");
				toReturn =  trashHandler.restoreItem(ses, (TrashItem)itemToRestore, (FolderItem) destinationItem, currentUser);
			} else 
				toReturn =  trashHandler.restoreItem(ses, (TrashItem)itemToRestore, null, currentUser);
			
		}catch(RepositoryException re ){
			log.error("error restoring item with id {}",trashedItemId, re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null) {
				ses.logout();
			}
		}
		
		return toReturn;
	}
	
	
	@Path("vrefolders")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemList getVreFolders(){
		InnerMethodName.instance.set("getVreFolders");
		Session ses = null;
		List<? extends Item> toReturn = null;
		org.gcube.common.storagehub.model.Path vrePath = null;
		try{
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			vrePath = pathUtil.getVREsPath(currentUser, ses);
			log.info("vres folder path is {}",vrePath.toPath());

			toReturn = Utils.getItemList(ses.getNode(vrePath.toPath()) , excludes, null, false, null);
		}catch(RepositoryException re ){
			log.error("error reading the node children of {}",vrePath, re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}

		return new ItemList(toReturn);
	}

	@Path("vrefolders/paged")
	@GET
	@Produces(MediaType.APPLICATION_JSON)
	public ItemList getVreFoldersPaged(@QueryParam("start") Integer start, @QueryParam("limit") Integer limit){
		InnerMethodName.instance.set("getVreFoldersPaged");
		Session ses = null;
		org.gcube.common.storagehub.model.Path vrePath = null;
		List<? extends Item> toReturn = null;
		try{
			ses = repository.getRepository().login(CredentialHandler.getAdminCredentials(context));
			vrePath = pathUtil.getVREsPath(currentUser, ses);
			toReturn = Utils.getItemList(ses.getNode(vrePath.toPath()) , excludes, new Range(start, limit), false, null);
		}catch(RepositoryException re ){
			log.error("(paged) error reading the node children of {}",vrePath, re);
			GXOutboundErrorResponse.throwException(new BackendGenericError(re));
		}catch(StorageHubException she ){
			log.error(she.getErrorMessage(), she);
			GXOutboundErrorResponse.throwException(she, Response.Status.fromStatusCode(she.getStatus()));
		}finally{
			if (ses!=null)
				ses.logout();
		}

		return new ItemList(toReturn);
	}


	
	@Path("count")
	@GET
	public String getTotalItemsCount(){
		InnerMethodName.instance.set("getTotalItemsCount");
		return folderHandler.getDefault().getStorageBackend().getTotalItemsCount();
	}
	
	
	@Path("size")
	@GET
	public String getTotalVolume(){
		InnerMethodName.instance.set("getTotalSize");
		return folderHandler.getDefault().getStorageBackend().getTotalSizeStored();
		
	}
	
}