package org.gcube.portlets.user.newsfeed.server;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.UUID;

import org.gcube.application.framework.core.session.ASLSession;
import org.gcube.application.framework.core.session.SessionManager;
import org.gcube.applicationsupportlayer.social.ApplicationNotificationsManager;
import org.gcube.applicationsupportlayer.social.NotificationsManager;
import org.gcube.common.core.utils.logging.GCUBEClientLog;
import org.gcube.portal.custom.communitymanager.OrganizationsUtil;
import org.gcube.portal.custom.scopemanager.scopehelper.ScopeHelper;
import org.gcube.portal.databook.server.DBCassandraAstyanaxImpl;
import org.gcube.portal.databook.server.DatabookStore;
import org.gcube.portal.databook.shared.Comment;
import org.gcube.portal.databook.shared.Feed;
import org.gcube.portal.databook.shared.Like;
import org.gcube.portal.databook.shared.UserInfo;
import org.gcube.portal.databook.shared.ex.ColumnNameNotFoundException;
import org.gcube.portal.databook.shared.ex.FeedIDNotFoundException;
import org.gcube.portal.databook.shared.ex.FeedTypeNotFoundException;
import org.gcube.portal.databook.shared.ex.PrivacyLevelTypeNotFoundException;
import org.gcube.portlets.user.newsfeed.client.NewsService;
import org.gcube.portlets.user.newsfeed.shared.EnhancedFeed;
import org.gcube.vomanagement.usermanagement.GroupManager;
import org.gcube.vomanagement.usermanagement.impl.liferay.LiferayGroupManager;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import com.liferay.portal.kernel.exception.PortalException;
import com.liferay.portal.kernel.exception.SystemException;
import com.liferay.portal.kernel.util.WebKeys;
import com.liferay.portal.model.Organization;
import com.liferay.portal.model.Role;
import com.liferay.portal.model.User;
import com.liferay.portal.model.UserModel;
import com.liferay.portal.service.OrganizationLocalServiceUtil;
import com.liferay.portal.service.UserLocalServiceUtil;
import com.liferay.portal.theme.ThemeDisplay;

/**
 * The server side implementation of the RPC service.
 */
@SuppressWarnings("serial")
public class NewsServiceImpl extends RemoteServiceServlet implements NewsService {

	private static GCUBEClientLog _log = new GCUBEClientLog(NewsServiceImpl.class);
	/**
	 * 
	 */
	private static final String ADMIN_ROLE = "Administrator";
	/**
	 * 
	 */
	private static final String SESSION_ADMIN_ATTR = "SESSION_ADMIN_ATTR";

	private DatabookStore store;

	private boolean withinPortal = false;

	private final static int MAX_FEEDS_NO = 20;


	//this is the cache for the user portraitsId that change among portals, the cache avoids to continuosly ask the LR DB the portraitID;
	private HashMap<String, Long> portraitIdCache;

	public void init() {
		store = new DBCassandraAstyanaxImpl();
		portraitIdCache = new HashMap<String, Long>();
	}

	public void destroy() {
		store.closeConnection();
	}

	/**
	 * 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) {
			_log.warn("USER IS NULL setting testing user and Running OUTSIDE PORTAL");
			//user = "test.user";
			user = "massimiliano.assante";
		}
		else {
			withinPortal = true;
		}
		return SessionManager.getInstance().getASLSession(sessionID, user);
	}

	@Override
	public ArrayList<EnhancedFeed> getAllUpdateUserFeeds() {
		String userName = getASLSession().getUsername();
		ArrayList<Feed> toMerge = new ArrayList<Feed>();
		HashMap<String, Feed> feedsMap = new HashMap<String, Feed>();
		try {
			if (!withinPortal) {
				return getEclipseResult(userName, false);
			}
			else {
				_log.info("****** retrieving feeds for user: " + userName);
				User currUser = OrganizationsUtil.validateUser(userName);

				//VRE Feeds
				for (Organization org : currUser.getOrganizations()) {
					GroupManager gm = new LiferayGroupManager();
					if (gm.isVRE(org.getOrganizationId()+"")) {
						String vreid = gm.getScope(""+org.getOrganizationId()); //get the scope 
						_log.trace("Reading feeds for VRE: " + vreid);
						ArrayList<Feed> OrganizationFeeds =  (ArrayList<Feed>) store.getRecentFeedsByVRE(vreid, 10); 
						for (Feed feed : OrganizationFeeds) {
							feedsMap.put(feed.getKey(), feed);							
						}
					}
				}
				//User Own Feeds
				ArrayList<Feed> userFeeds = (ArrayList<Feed>) store.getRecentFeedsByUser(userName, 10);	
				for (Feed feed : userFeeds) {
					feedsMap.put(feed.getKey(), feed);
				}

				//UserFriends Feeds
				ArrayList<String> userFriendsIds = (ArrayList<String>)store.getFriends(userName);
				for (String userid : userFriendsIds) {
					for (Feed feed : store.getRecentFeedsByUser(userid, 10)) {
						feedsMap.put(feed.getKey(), feed);
					}
				}

				//Portal Feeds
				ArrayList<Feed> portalFeeds = (ArrayList<Feed>) store.getAllPortalPrivacyLevelFeeds();	
				for (Feed feed : portalFeeds) {
					feedsMap.put(feed.getKey(), feed);
				}

				for (String key: feedsMap.keySet()) {
					toMerge.add(feedsMap.get(key));
				}				
			}
			ArrayList<Feed> toReturn = new ArrayList<Feed>();
			//return only <MAX_FEEDS_NO> feeds
			if (toMerge.size() > MAX_FEEDS_NO) 
				for (int i = 0; i < MAX_FEEDS_NO; i++) 
					toReturn.add(toMerge.get(i));
			else {
				return enhanceFeeds(toMerge);
			}
			return enhanceFeeds(toReturn);
		} catch (PrivacyLevelTypeNotFoundException e) {
			_log.error("Privacy Level not Found " + e.getMessage());
			e.printStackTrace();
		} catch (FeedTypeNotFoundException e) {
			_log.error("Feed Type not Found " + e.getMessage());
			e.printStackTrace();
		} catch (ColumnNameNotFoundException e) {
			_log.error("Column name not Found " + e.getMessage());
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * return only the user connection feeds
	 */
	@Override
	public ArrayList<EnhancedFeed> getOnlyConnectionsUserFeeds() {
		ArrayList<Feed> toMerge = new ArrayList<Feed>();
		HashMap<String, Feed> feedsMap = new HashMap<String, Feed>();
		String userName = getASLSession().getUsername();
		try {
			if (! withinPortal) {
				return getEclipseResult(userName, true);
			}
			else {
				//UserFriends Feeds
				ArrayList<String> userFriendsIds = (ArrayList<String>)store.getFriends(userName);
				for (String userid : userFriendsIds) {
					for (Feed feed : store.getRecentFeedsByUser(userid, 10)) {
						feedsMap.put(feed.getKey(), feed);
					}
				}
				for (String key: feedsMap.keySet()) {
					toMerge.add(feedsMap.get(key));
				}
				Collections.sort(toMerge, Collections.reverseOrder());
				ArrayList<Feed> toReturn = new ArrayList<Feed>();
				//return only <MAX_FEEDS_NO> feeds
				if (toMerge.size() > MAX_FEEDS_NO) 
					for (int i = 0; i < MAX_FEEDS_NO; i++) 
						toReturn.add(toMerge.get(i));
				else
					return enhanceFeeds(toMerge);;		
			}
		} catch (PrivacyLevelTypeNotFoundException e) {
			_log.error("Privacy Level not Found " + e.getMessage());
			e.printStackTrace();
		} catch (FeedTypeNotFoundException e) {
			_log.error("Feed Type not Found " + e.getMessage());
			e.printStackTrace();
		} catch (ColumnNameNotFoundException e) {
			_log.error("Column name not Found " + e.getMessage());
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}
	
	


	/**
	 * just for testing purposes
	 * 
	 * @param userName
	 * @return
	 * @throws PrivacyLevelTypeNotFoundException
	 * @throws FeedTypeNotFoundException
	 * @throws ColumnNameNotFoundException
	 * @throws FeedIDNotFoundException 
	 */
	private ArrayList<EnhancedFeed> getEclipseResult(String userName, boolean onlyConnections) throws PrivacyLevelTypeNotFoundException, FeedTypeNotFoundException, ColumnNameNotFoundException, FeedIDNotFoundException {
		ArrayList<Feed> toMerge = new ArrayList<Feed>();
		HashMap<String, Feed> feedsMap = new HashMap<String, Feed>();

		ArrayList<Feed> OrganizationFeeds =  (ArrayList<Feed>) store.getRecentFeedsByVRE("/gcube/devsec/devVRE", 10); 
		for (Feed feed : OrganizationFeeds) {
			feedsMap.put(feed.getKey(), feed);
		}

		if (! onlyConnections) {
			//User Own Feeds
			ArrayList<Feed> userFeeds = (ArrayList<Feed>) store.getRecentFeedsByUser(userName, 10);	
			for (Feed feed : userFeeds) 
				feedsMap.put(feed.getKey(), feed);			
			//			//Portal Feeds
			ArrayList<Feed> portalFeeds = (ArrayList<Feed>) store.getAllPortalPrivacyLevelFeeds();	
			for (Feed feed : portalFeeds) 
				feedsMap.put(feed.getKey(), feed);			
		}
		//UserFriends Feeds
		ArrayList<String> userFriendsIds = (ArrayList<String>)store.getFriends(userName);
		for (String userid : userFriendsIds) {
			for (Feed feed : store.getRecentFeedsByUser(userid, 10)) {
				feedsMap.put(feed.getKey(), feed);
			}
		}
		for (String key: feedsMap.keySet()) {
			toMerge.add(feedsMap.get(key));
		}
		for (Feed feed : toMerge) {
			feed.setThumbnailURL("http://127.0.0.1:8888/images/Avatar_default.png");
		}

		return enhanceFeeds(toMerge);
	}

	@Override
	public ArrayList<EnhancedFeed> getOnlyMyUserFeeds() {
		String userName = getASLSession().getUsername();
		_log.trace("getOnly UserFeeds for " + userName);
		ArrayList<Feed> userFeeds = null;
		try {
			userFeeds = (ArrayList<Feed>) store.getRecentFeedsByUser(userName, 15);
		} catch (Exception e) {
			e.printStackTrace();
		} 
		return enhanceFeeds(userFeeds);
	}
	
	@Override
	public ArrayList<EnhancedFeed> getOnlyLikedFeeds() {
		String userName = getASLSession().getUsername();
		_log.trace("getLiked Feeds for " + userName);
		ArrayList<Feed> userFeeds = null;
		try {
			userFeeds = (ArrayList<Feed>) store.getAllLikedFeedsByUser(userName, 25);
		} catch (Exception e) {
			e.printStackTrace();
		} 
		return enhanceFeeds(userFeeds);
	}

	@Override
	public boolean like(String feedid, String feedText, String feedOwnerId) {
		boolean likeCommitResult = false;
		UserInfo user = getUserInfo();
		Like toLike = new Like(UUID.randomUUID().toString(), user.getUsername(), 
				new Date(), feedid, user.getFullName(), user.getAvatarId());
		try {
			likeCommitResult = store.like(toLike);
		} catch (FeedIDNotFoundException e) {
			_log.error("Feed not Found for this like " + e.getMessage());
			e.printStackTrace();
			return false;
		}
		//if the like was correctly delivered notify users involved
		if (likeCommitResult) {
			//if the user who liked this post is not the user who posted it notify the poster user (Feed owner) 
			if (! user.getUsername().equals(feedOwnerId)) {
					NotificationsManager nm = new ApplicationNotificationsManager(getASLSession());
					boolean nResult = nm.notifyLikedFeed(feedOwnerId, feedid, escapeHtml(feedText));
				_log.trace("Like Notification added? " + nResult);
			}
		}
		return likeCommitResult;
	}
	/**
	 * @param feedid the id of the commented feed
	 * @param commentText the comment text
	 * @param feedOwnerId the username of the user who created the post that was commented
	 */
	@Override
	public Comment comment(String feedid, String commentText, String feedOwnerId) {
		boolean commentCommitResult = false;
		_log.trace("Trying to add this comment " + commentText);
		UserInfo user = getUserInfo();
		Comment comment = new Comment(UUID.randomUUID().toString(), user.getUsername(), 
				new Date(), feedid, escapeHtml(commentText), user.getFullName(), user.getAvatarId());
		try {
			if (store.addComment(comment)) 
				commentCommitResult = true;
		} catch (FeedIDNotFoundException e) {
			_log.error("Feed not Found for this comment " + e.getMessage());
			e.printStackTrace();
			return null;
		}
		//if the comment was correctly delivered notify users involved
		if (commentCommitResult) {
			//if the user who commented this post is not the user who posted it notify the poster user (Feed owner) 
			NotificationsManager nm = new ApplicationNotificationsManager(getASLSession());
			if (! user.getUsername().equals(feedOwnerId)) {				
				boolean result = nm.notifyOwnCommentReply(feedOwnerId, feedid, escapeHtml(commentText));
				_log.trace("Comment Notification to post owner added? " + result);
			}
			//if there are other users who liked this post they get notified too, asynchronously with this thread
			Thread thread = new Thread(new NotificationsThread(commentText, nm, getAllLikesByFeed(feedid)));
	        thread.start();
		}
		return comment;
	}

	private String replaceAmpersand(String toReplace) {
		String toReturn = toReplace.replaceAll("&amp;", "&");
		return toReturn;
	}
	/**
	 * this method sorts the Feeds in Chronological Reversed order and adds additional user informations 
	 * @param toEnhance
	 * @return
	 */
	private ArrayList<EnhancedFeed> enhanceFeeds(ArrayList<Feed> toEnhance) {
		ArrayList<EnhancedFeed> toReturn = new ArrayList<EnhancedFeed>();
		String username = getASLSession().getUsername();
		//sort the Feeds
		Collections.sort(toEnhance, Collections.reverseOrder());
		ArrayList<String> likedFeeds = (ArrayList<String>) store.getAllLikedFeedIdsByUser(getASLSession().getUsername());
//		System.out.println("Liked Feed for " + username);
//		for (String liked : likedFeeds) {
//			System.out.println(liked);
//		}

		for (Feed feed : toEnhance) {
			feed.setDescription(replaceAmpersand(feed.getDescription()));
			if (! feed.isApplicationFeed())
				feed.setThumbnailURL(getUserImagePortraitUrlLocal(feed.getEntityId()));
			//if likedFeeds contains this feed key it means the user already Liked it
			boolean liked = likedFeeds.contains(feed.getKey());
			int commentsNo = 0;
			try {
				commentsNo = Integer.parseInt(feed.getCommentsNo());
			}
			catch (NumberFormatException e) {
				commentsNo = 0;
				_log.error("NumberFormatException while reading comments number " + e.getMessage());
			}
			if (commentsNo == 0) {
				EnhancedFeed toAdd = null;
				//create the enhanced feed
				if (feed.isApplicationFeed()) {
					toAdd = new EnhancedFeed(feed, liked, checkisAdminUser()); 
				} else
					toAdd = new EnhancedFeed(feed, liked, isUsers(feed, username)); 
				toReturn.add(toAdd);
			} else {
				ArrayList<Comment> comments = getAllCommentsByFeed(feed.getKey());
				//sort in chronological order
				Collections.sort(comments);

				//TODO: retrieve only the first 2 more recents efficiently from the store
				//only the first two first 2 more recent returned to the client initially

				int currCommentsNumber = comments.size();
				//if comments are less than 2 they are the more recent
				if (currCommentsNumber < 2) {
					EnhancedFeed toAdd = new EnhancedFeed(feed, liked, isUsers(feed, username), comments); 
					toReturn.add(toAdd);
				} else {
					//need to get the last two
					ArrayList<Comment> comments2Attach = new ArrayList<Comment>();					
					for (int i = currCommentsNumber -2; i < currCommentsNumber; i++) {
						comments2Attach.add(comments.get(i));
					}
					EnhancedFeed toAdd = new EnhancedFeed(feed, liked, isUsers(feed, username), comments2Attach); 
					toReturn.add(toAdd);
				}				
			}

		}
		_log.trace("****** ENHANCED FEEDS TOTAL= " + toReturn.size());
		return toReturn;
	}

	/**
	 * this method is needed because user images portrait change id depending on the portal instance
	 * e.g. a post made from iMarine portal would not show the avatarIMage in D4Science.org
	 * @param screenname
	 * @return the url of the image portrait for this portal instance
	 */
	private String getUserImagePortraitUrlLocal(String screenName) {
		if (! withinPortal) {
			return "";
		}
		StringBuilder thumbnailURL = new StringBuilder("/image/user_male_portrait?img_id=");
//		if (portraitIdCache.containsKey(screenName))
//			return thumbnailURL.append(portraitIdCache.get(screenName)).toString();
//		else {
			User user = null;
			try {
				user = UserLocalServiceUtil.getUserByScreenName(OrganizationsUtil.getCompany().getCompanyId(), screenName);
//				portraitIdCache.put(screenName, user.getPortraitId());
			} catch (PortalException e) {
				e.printStackTrace();
			} catch (SystemException e) {
				e.printStackTrace();
			}
			return thumbnailURL.append(user.getPortraitId()).toString();
//		}
	}


	@Override
	public UserInfo getUserInfo() {
		if (getUserFromSession() != null)
			return getUserFromSession();
		try {
			String username = getASLSession().getUsername();
			String email = username+"@isti.cnr.it";
			String fullName = username+" FULL";
			String thumbnailURL = "images/Avatar_default.png";

			if (withinPortal) {
				UserModel user = UserLocalServiceUtil.getUserByScreenName(OrganizationsUtil.getCompany().getCompanyId(), username);
				thumbnailURL = "/image/user_male_portrait?img_id="+user.getPortraitId();
				fullName = user.getFirstName() + " " + user.getLastName();
				email = user.getEmailAddress();
				ThemeDisplay themeDisplay = (ThemeDisplay) this.getThreadLocalRequest().getSession().getAttribute(WebKeys.THEME_DISPLAY);
				String accountURL = themeDisplay.getURLMyAccount().toString();
				UserInfo toReturn = new UserInfo(username, fullName, thumbnailURL, user.getEmailAddress(), accountURL, true, false, null);
				setUserInSession(toReturn);
				return toReturn;
			}
			else {
				_log.info("Returning test USER");
				return new UserInfo(getASLSession().getUsername(), fullName, thumbnailURL, email, "fakeAccountUrl", true, false, null);
			}

		} catch (Exception e) {
			e.printStackTrace();
		}
		return new UserInfo();
	}

	@Override
	public ArrayList<Like> getAllLikesByFeed(String feedid) {
		ArrayList<Like> toReturn = (ArrayList<Like>) store.getAllLikesByFeed(feedid);
		_log.trace("Asking likes for " + feedid);
		for (Like like : toReturn) {
			like.setThumbnailURL(getUserImagePortraitUrlLocal(like.getUserid()));
		}
		return toReturn;
	}

	@Override
	public ArrayList<Comment> getAllCommentsByFeed(String feedid) {
		_log.trace("Asking comments for " + feedid);
		ArrayList<Comment> toReturn =  (ArrayList<Comment>) store.getAllCommentByFeed(feedid);
		for (Comment comment : toReturn) {
			comment.setThumbnailURL(getUserImagePortraitUrlLocal(comment.getUserid()));
		}
		Collections.sort(toReturn);
		return toReturn;
	}
	@Override
	public boolean deleteComment(String commentid, String feedid) {
		_log.trace("Attempting to delete comment " + commentid);
		try {
			return store.deleteComment(commentid, feedid);
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		} 
	}
	@Override
	public boolean deleteFeed(String feedid) {
		_log.trace("Attempting to delete feed " + feedid);
		try {
			return store.deleteFeed(feedid);
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		} 
	}

	private UserInfo getUserFromSession() {
		return (UserInfo) getASLSession().getAttribute(UserInfo.USER_INFO_ATTR);
	}

	private void setUserInSession(UserInfo user) {
		getASLSession().setAttribute(UserInfo.USER_INFO_ATTR, user);
	}
	/**
	 * tell if a feed is belonging to the current user or not
	 * @param tocheck
	 * @param username
	 * @return true if this feed is of the current user
	 */
	private boolean isUsers(Feed tocheck, String username) {
		return (tocheck.getEntityId().equals(username));
	}
	/**
	 * Escape an html string. Escaping data received from the client helps to
	 * prevent cross-site script vulnerabilities.
	 * 
	 * @param html the html string to escape
	 * @return the escaped string
	 */
	private String escapeHtml(String html) {
		if (html == null) {
			return null;
		}
		return html.replaceAll("&", "&amp;").replaceAll("<", "&lt;")
				.replaceAll(">", "&gt;");
	}

	@Override
	public Comment editComment(Comment toEdit) {
		UserInfo user = getUserInfo();
		Comment edited = new Comment(toEdit.getKey(), toEdit.getUserid(), 
				new Date(), toEdit.getFeedid(), escapeHtml(toEdit.getText()), user.getFullName(), user.getAvatarId());
		try {
			store.editComment(edited);
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		} 
		return edited;
	}	
	/**
	 * 
	 * @return true if the user is a portal administrator or not
	 */
	private boolean checkisAdminUser() {
		if (getASLSession().getAttribute(SESSION_ADMIN_ATTR) == null) {
			boolean isAdmin = false;
			try {
				isAdmin = isAdmin();
			} catch (Exception e) {
				e.printStackTrace();
			} 
			getASLSession().setAttribute(SESSION_ADMIN_ATTR, isAdmin);
			return isAdmin;
		}
		return (Boolean) getASLSession().getAttribute(SESSION_ADMIN_ATTR);
	}
	/**
	 * tell if the user is a portal administrator or not
	 * @param username
	 * @return true if is admin
	 * @throws SystemException 
	 * @throws PortalException 
	 */
	private boolean isAdmin() throws PortalException, SystemException  {
		User currUser = OrganizationsUtil.validateUser(getASLSession().getUsername());
		List<Organization> organizations = OrganizationLocalServiceUtil.getOrganizations(0, OrganizationLocalServiceUtil.getOrganizationsCount());
		Organization rootOrganization = null;
		for (Organization organization : organizations) {
			if (organization.getName().equals(OrganizationsUtil.getRootOrganizationName() ) ) {
				rootOrganization = organization;
				break;
			}
		}		
		try {
			_log.trace("root: " + rootOrganization.getName() );
			return (hasRole(ADMIN_ROLE, rootOrganization.getName(), currUser));
		}
		catch (NullPointerException e) {
			_log.error("Cannot find root organziation, please check gcube-data.properties file in $CATALINA_HOME/conf folder");
			return false;
		}
	}
	/**
	 * 
	 * @param rolename
	 * @param organizationName
	 * @param user
	 * @return
	 * @throws SystemException 
	 */
	private boolean hasRole(String rolename, String organizationName, User user) throws SystemException {
		for (Role role : user.getRoles()) 
			if (role.getName().compareTo(rolename) == 0 ) 
				return true;
		return false;
	}
}