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

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.TimeUnit;

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.HomeNotFoundException;
import org.gcube.common.homelibrary.home.exceptions.InternalErrorException;
import org.gcube.common.homelibrary.home.workspace.Workspace;
import org.gcube.common.homelibrary.home.workspace.WorkspaceFolder;
import org.gcube.common.homelibrary.home.workspace.WorkspaceItem;
import org.gcube.common.homelibrary.home.workspace.exceptions.WorkspaceFolderNotFoundException;
import org.gcube.portlets.widgets.wsexplorer.client.WorkspaceExplorerConstants;
import org.gcube.portlets.widgets.wsexplorer.client.rpc.WorkspaceExplorerService;
import org.gcube.portlets.widgets.wsexplorer.shared.FilterCriteria;
import org.gcube.portlets.widgets.wsexplorer.shared.Item;
import org.gcube.portlets.widgets.wsexplorer.shared.ItemCategory;
import org.gcube.portlets.widgets.wsexplorer.shared.ItemType;
import org.gcube.portlets.widgets.wsexplorer.shared.WorkspaceNavigatorServiceException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;

/**
 * The server side implementation of the RPC service.
 *
 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
 * Jun 25, 2015
 */
@SuppressWarnings("serial")
public class WorkspaceExplorerServiceImpl extends RemoteServiceServlet implements WorkspaceExplorerService {

	/**
	 * 
	 */
	public static final Logger _log = LoggerFactory.getLogger(WorkspaceExplorerServiceImpl.class);
	public static final String USERNAME_ATTRIBUTE = "username";
	public static final String TEST_USER = "francesco.mangiacrapa";

	
	/**
	 * Gets the ASL session.
	 *
	 * @param httpSession the http session
	 * @return the ASL session
	 */
	private ASLSession getASLSession(HttpSession httpSession)	{
		String sessionID = httpSession.getId();
		String user = (String) httpSession.getAttribute(USERNAME_ATTRIBUTE);

		_log.error("WORKSPACE PORTLET SessionID= " + sessionID);
		
		//TODO we check for the older attribute name
		if (user == null) user = (String) httpSession.getAttribute("user");

		if (user == null) {

			_log.error("WORKSPACE PORTLET STARTING IN TEST MODE - NO USER FOUND");

			//for test only
//			user = "test.user";
			user = TEST_USER;
			httpSession.setAttribute(USERNAME_ATTRIBUTE, user);
			ASLSession session = SessionManager.getInstance().getASLSession(sessionID, user);
			session.setScope("/gcube/devsec/devVRE");

			return session;
		} else _log.trace("user found in session "+user);
		return SessionManager.getInstance().getASLSession(sessionID, user);
	}


	/**
	 * Gets the workspace.
	 *
	 * @return the workspace
	 * @throws InternalErrorException the internal error exception
	 * @throws HomeNotFoundException the home not found exception
	 * @throws WorkspaceFolderNotFoundException the workspace folder not found exception
	 */
	protected Workspace getWorkspace() throws InternalErrorException, HomeNotFoundException, WorkspaceFolderNotFoundException	{
		ASLSession session = getASLSession(this.getThreadLocalRequest().getSession());
		
		Workspace workspace = HomeLibrary.getUserWorkspace(session.getUsername());
		return workspace;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public Item getRoot(List<ItemType> showableTypes, boolean purgeEmpyFolders, FilterCriteria filterCriteria) throws WorkspaceNavigatorServiceException {
		_log.trace("getRoot showableTypes: "+showableTypes+" purgeEmpyFolders: "+purgeEmpyFolders+" filterCriteria: "+ filterCriteria);
	
		try {

			Workspace workspace = getWorkspace();
			_log.trace("Start getRoot...");
			
			WorkspaceItem root = workspace.getRoot();

			_log.trace("GetRoot  - Replyiing root");
			long startTime = System.currentTimeMillis();
			_log.trace("start time - " + startTime);

			Item rootItem = ItemBuilder.getItem(null, root, showableTypes, filterCriteria, true);
			rootItem.setName(WorkspaceExplorerConstants.HOME_LABEL);
	
			/* SPECIAL FOLDERS
			Item specialFolders = ItemBuilder.getItem(null, specials, showableTypes, filterCriteria, 2);
			specialFolders.setShared(true);
			rootItem.addChild(specialFolders);		
			 */
			if (purgeEmpyFolders) rootItem = ItemBuilder.purgeEmptyFolders(rootItem);

			_log.trace("Returning:");
			Long endTime = System.currentTimeMillis() - startTime;
			String time = String.format("%d msc %d sec", endTime, TimeUnit.MILLISECONDS.toSeconds(endTime));
			_log.trace("end time - " + time);

			Collections.sort(rootItem.getChildren(), new ItemComparator());
			_log.info("Returning children size: "+rootItem.getChildren().size());
			
			return rootItem;

		} catch (Exception e) {
			_log.error("Error during root retrieving", e);
			throw new WorkspaceNavigatorServiceException("Sorry, an error occurred when performing get root");
		}
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public Item getFolder(String folderId, List<ItemType> showableTypes, boolean purgeEmpyFolders, FilterCriteria filterCriteria) throws WorkspaceNavigatorServiceException {
		_log.trace("getFolder folderId: "+folderId+" showableTypes: "+showableTypes+" purgeEmpyFolders: "+purgeEmpyFolders+" filterCriteria: "+filterCriteria);

		try {

			Workspace workspace = getWorkspace();
			WorkspaceItem folder = workspace.getItem(folderId);

			_log.trace("GetFolder - Replyiing folder");
			long startTime = System.currentTimeMillis();
			_log.trace("start time - " + startTime);

			Item itemFolder = ItemBuilder.getItem(null, folder, showableTypes, filterCriteria, true);
			_log.trace("Only showable types:");
			
			if (purgeEmpyFolders) itemFolder = ItemBuilder.purgeEmptyFolders(itemFolder);

			_log.trace("Returning:");
			Long endTime = System.currentTimeMillis() - startTime;
			String time = String.format("%d msc %d sec", endTime, TimeUnit.MILLISECONDS.toSeconds(endTime));
			_log.trace("end time - " + time);

			Collections.sort(itemFolder.getChildren(), new ItemComparator());

			return itemFolder;

		} catch (Exception e) {
			_log.error("Error during folder retrieving", e);
			throw new WorkspaceNavigatorServiceException("Sorry, an error occurred when performing get folder");
		}
	}
	
	@Override
	public Item getItemByCategory(ItemCategory category) throws WorkspaceNavigatorServiceException{
		_log.trace("GetItemByCategory category: "+category);
		try {
			Workspace workspace = getWorkspace();
			Item item = null;
			
			switch(category){
				case HOME:{
					WorkspaceItem root = workspace.getRoot();
					ASLSession session = getASLSession(this.getThreadLocalRequest().getSession());
					String fullName = UserUtil.getUserFullName(session.getUsername());
					if(fullName.indexOf(" ")>0){
						fullName = fullName.substring(0, fullName.indexOf(" "));
					}else if(fullName.indexOf(".")>0){
						fullName = fullName.substring(0, fullName.indexOf("."));
					}
					item = new Item(null, root.getId(), fullName+"'s", ItemType.ROOT, root.getPath(), root.getOwner().getPortalLogin(), true, true);
					break;
				}
				case VRE_FOLDER:{
					WorkspaceItem folder = workspace.getMySpecialFolders();
					item = new Item(null, folder.getId(), WorkspaceExplorerConstants.VRE_FOLDERS_LABEL, ItemType.FOLDER, folder.getPath(), folder.getOwner().getPortalLogin(), true, false);
					break;
				}
			}
			return item;
		} catch (Exception e) {
			_log.error("Error during get item by category", e);
			throw new WorkspaceNavigatorServiceException("Sorry, an error occurred when performing get item by category");
		}
	}
	
	/**
	 * {@inheritDoc}
	 */
	@Override
	public Item getMySpecialFolder(List<ItemType> showableTypes, boolean purgeEmpyFolders, FilterCriteria filterCriteria) throws WorkspaceNavigatorServiceException {
		_log.trace("GetMySpecialFolder showableTypes: "+showableTypes+" purgeEmpyFolders: "+purgeEmpyFolders+" filterCriteria: "+filterCriteria);

		try {

			Workspace workspace = getWorkspace();
			WorkspaceItem folder = workspace.getMySpecialFolders();

			long startTime = System.currentTimeMillis();
			_log.trace("start time - " + startTime);


			Item itemFolder = ItemBuilder.getItem(null, folder, showableTypes, filterCriteria, true);
			itemFolder.setName(WorkspaceExplorerConstants.VRE_FOLDERS_LABEL);
			itemFolder.setSpecialFolder(true);
			
			_log.trace("Builded MySpecialFolder: "+itemFolder);

			_log.trace("Only showable types:");
			//printName("", folderItem);

			if (purgeEmpyFolders) itemFolder = ItemBuilder.purgeEmptyFolders(itemFolder);

			_log.trace("Returning:");

			Long endTime = System.currentTimeMillis() - startTime;
			String time = String.format("%d msc %d sec", endTime, TimeUnit.MILLISECONDS.toSeconds(endTime));
			_log.trace("end time - " + time);

			//printName("", folderItem);
			
			Collections.sort(itemFolder.getChildren(), new ItemComparator());

			return itemFolder;

		} catch (Exception e) {
			_log.error("Error during special folders retrieving", e);
			throw new WorkspaceNavigatorServiceException("Sorry, an error occurred when performing get My Special Folder");
		}
	}


	/**
	 * {@inheritDoc}
	 */
	@Override
	public boolean checkName(String name) throws WorkspaceNavigatorServiceException {
		_log.trace("checkName name: "+name);
		try {
			ASLSession session = getASLSession(this.getThreadLocalRequest().getSession());
			Workspace workspace = HomeLibrary.getUserWorkspace(session.getUsername());
			return workspace.isValidName(name);
		} catch (Exception e) {
			_log.error("Error during folder retrieving", e);
			throw new WorkspaceNavigatorServiceException(e.getMessage());
		}
	}

	/*protected void printName(String indentation, Item item)
	{
		if(item!=null){
			_log.trace(indentation+item.getName());
			for (Item child:item.getChildren()) printName(indentation+"\t", child);
		}
	}*/
	
	/**
	 * Gets Breadcrumbs (the list of parents) by item identifier.
	 *
	 * @param itemIdentifier the item identifier
	 * @param includeItemAsParent -  if parameter is true and item passed in input is a folder, the folder is included in path returned as last parent
	 * @return the list parents by item identifier
	 * @throws Exception the exception
	 */
	@Override
	public List<Item> getBreadcrumbsByItemIdentifier(String itemIdentifier, boolean includeItemAsParent) throws Exception {
		List<Item> listParents = new ArrayList<Item>();
		_log.trace("ListParents By Item Identifier "+ itemIdentifier);
		try {
			
			Workspace workspace = getWorkspace();
			WorkspaceItem wsItem = workspace.getItem(itemIdentifier);
		
			_log.trace("workspace retrieve item name: "+wsItem.getName());

			if(includeItemAsParent==true && wsItem.isFolder()){
				listParents.add(ItemBuilder.buildFolderForBreadcrumbs((WorkspaceFolder) wsItem, null));
			}
			
			//HANDLE MY_SPECIAL_FOLDER
			if(wsItem.isFolder()){
				if(ItemBuilder.isSpecialFolder((WorkspaceFolder) wsItem))
					return listParents;
			}

			//CREATING LIST PARENTS
			while(wsItem!=null && wsItem.getParent()!=null){
				WorkspaceFolder wsParentFolder = wsItem.getParent();
				Item parent = ItemBuilder.buildFolderForBreadcrumbs((WorkspaceFolder) wsParentFolder, null);
				listParents.add(parent);
				if(parent.isSpecialFolder()) //SKIP HOME PARENT FOR MY_SPECIAL_FOLDER
					break;
				wsItem = wsParentFolder;
			}
			
			Collections.reverse(listParents);
			/*
			System.out.println("Parent's:");
			for (Item item : listParents) {
				System.out.println(item);
			}*/

			//SET PARENTS
			for(int i=0; i<listParents.size()-1; i++){
				Item parent = listParents.get(i);
				Item fileModel = listParents.get(i+1);
				fileModel.setParent(parent);
			}

			_log.trace("ListParents return size: "+listParents.size());
			
		} catch (Exception e) {
			_log.error("Error in get List Parents By Item Identifier ", e);
			e.printStackTrace();
			throw new Exception(e.getMessage());
		}

		return listParents;
	}
}