package org.gcube.portlets.user.newsfeed.client.panels;

import java.util.ArrayList;

import org.gcube.portal.databook.shared.ClientFeed;
import org.gcube.portal.databook.shared.Comment;
import org.gcube.portal.databook.shared.Feed;
import org.gcube.portal.databook.shared.FeedType;
import org.gcube.portal.databook.shared.Like;
import org.gcube.portal.databook.shared.PrivacyLevel;
import org.gcube.portal.databook.shared.UserInfo;
import org.gcube.portlets.user.newsfeed.client.FilterType;
import org.gcube.portlets.user.newsfeed.client.NewsService;
import org.gcube.portlets.user.newsfeed.client.NewsServiceAsync;
import org.gcube.portlets.user.newsfeed.client.event.AddCommentEvent;
import org.gcube.portlets.user.newsfeed.client.event.AddCommentEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.AddLikeEvent;
import org.gcube.portlets.user.newsfeed.client.event.AddLikeEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.DeleteCommentEvent;
import org.gcube.portlets.user.newsfeed.client.event.DeleteCommentEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.DeleteFeedEvent;
import org.gcube.portlets.user.newsfeed.client.event.DeleteFeedEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.EditCommentEvent;
import org.gcube.portlets.user.newsfeed.client.event.EditCommentEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.SeeCommentsEvent;
import org.gcube.portlets.user.newsfeed.client.event.SeeCommentsEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.SeeLikesEvent;
import org.gcube.portlets.user.newsfeed.client.event.SeeLikesEventHandler;
import org.gcube.portlets.user.newsfeed.client.event.StopTimerEvent;
import org.gcube.portlets.user.newsfeed.client.event.StopTimerEventHandler;
import org.gcube.portlets.user.newsfeed.client.panels.dialog.LikesDialog;
import org.gcube.portlets.user.newsfeed.client.templates.FilterPanel;
import org.gcube.portlets.user.newsfeed.client.templates.SingleComment;
import org.gcube.portlets.user.newsfeed.client.templates.TweetTemplate;
import org.gcube.portlets.user.newsfeed.shared.EnhancedFeed;

import com.google.gwt.core.client.GWT;
import com.google.gwt.core.client.RunAsyncCallback;
import com.google.gwt.event.shared.HandlerManager;
import com.google.gwt.user.client.Timer;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.HasAlignment;
import com.google.gwt.user.client.ui.HasVerticalAlignment;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Image;
import com.google.gwt.user.client.ui.VerticalPanel;
/**
 * 
 * @author Massimiliano Assante, ISTI-CNR
 *
 */
public class NewsFeedPanel extends Composite {

	/**
	 * Create a remote service proxy to talk to the server-side News service.
	 */
	private final NewsServiceAsync newsService = GWT.create(NewsService.class);
	private final HandlerManager eventBus = new HandlerManager(null);

	private VerticalPanel mainPanel = new VerticalPanel();
	private HorizontalPanel filterPanel = new HorizontalPanel();
	private VerticalPanel newsPanel = new VerticalPanel();

	private static final String warning = GWT.getModuleBaseURL() + "../images/warning_blue.png";
	private static final String spacer = GWT.getModuleBaseURL() + "../images/feeds-spacer.gif";
	public static final String loading = GWT.getModuleBaseURL() + "../images/feeds-loader.gif";
	
	public static final String LIKE_LABEL = "Favorite";
	public static final String LIKED_LABEL = "Favorited";
	public static final String COMMENT_LABEL = "Reply";
	public static final String MESSAGE_LABEL =  "Message";
	
	public static final int delayMillis = 300000;  //5 minutes

	private boolean isFirstTweet = false;

	private Image loadingImage;
	private UserInfo myUserInfo;

	private FilterType currentFilter;
	private Timer feedsTimer;
	/**
	 * events binder
	 */
	private void bind() {
		
		eventBus.addHandler(StopTimerEvent.TYPE, new StopTimerEventHandler() {
			@Override
			public void onStopTimer(StopTimerEvent event) {
				GWT.log("Stop timer");
				if (event.isRestart())
					resetTimer();
				else
					stopTimer();
			}
		});  

		eventBus.addHandler(AddLikeEvent.TYPE, new AddLikeEventHandler() {
			@Override
			public void onAddLike(AddLikeEvent event) {
				resetTimer();
				doAddLike( event.getOwner(), event.getFeedId());
			}
		});  

		eventBus.addHandler(AddCommentEvent.TYPE, new AddCommentEventHandler() {
			@Override
			public void onAddComment(AddCommentEvent event) {
				resetTimer();
				doAddComment(event.getOwner(), event.getText());
			}
		});  

		eventBus.addHandler(EditCommentEvent.TYPE, new EditCommentEventHandler() {
			@Override
			public void onEditComment(EditCommentEvent event) {
				resetTimer();
				doEditComment(event.getOwner(), event.getCommentInstance());
			}
		});  


		eventBus.addHandler(SeeLikesEvent.TYPE, new SeeLikesEventHandler() {
			@Override
			public void onSeeLikes(SeeLikesEvent event) {
				resetTimer();
				doShowLikes(event.getFeedId());
			}
		});  

		eventBus.addHandler(SeeCommentsEvent.TYPE, new SeeCommentsEventHandler() {
			@Override
			public void onSeeComments(SeeCommentsEvent event) {
				resetTimer();
				doShowComments(event.getOwner(), event.isCommentForm2Add());	
			}
		});  

		eventBus.addHandler(DeleteCommentEvent.TYPE, new DeleteCommentEventHandler() {
			@Override
			public void onDeleteComment(DeleteCommentEvent event) {
				resetTimer();
				doDeleteComment(event.getOwner(), event.getCommentId());
			}
		});  

		eventBus.addHandler(DeleteFeedEvent.TYPE, new DeleteFeedEventHandler() {
			@Override
			public void onDeleteFeed(DeleteFeedEvent event) {
				resetTimer();
				doDeleteFeed(event.getToDelete());
			}			
		});  
	}



	/**
	 * 
	 */
	public NewsFeedPanel() {
		bind();
		mainPanel.add(filterPanel);
		mainPanel.add(newsPanel);

		filterPanel.add(new FilterPanel(this, newsService));
		initWidget(mainPanel);
		newsPanel.clear();
		newsPanel.setWidth("100%");
		newsPanel.setHeight("300px");
		newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_CENTER);
		newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_TOP);
		loadingImage = new Image(loading);
		newsPanel.add(loadingImage);

		newsService.getUserInfo(new AsyncCallback<UserInfo>() {
			@Override
			public void onFailure(Throwable caught) {		
			}

			@Override
			public void onSuccess(UserInfo result) {
				myUserInfo = result;	
				if (result.getUsername().equals("test.user")) {
					Window.alert("Your session has expired, please log out and login again");
				} 
				else {
					showAllUpdatesFeeds();
					currentFilter = FilterType.ALL_UPDATES;
				}
			}
		});
		
		feedsTimer = new Timer() {
			@Override
			public void run() {
				refreshFeeds();
			}
		};
		feedsTimer.scheduleRepeating(delayMillis);
	}
	
	private void resetTimer() {
		feedsTimer.cancel();
		feedsTimer.scheduleRepeating(delayMillis);
	}
	private void stopTimer() {
		feedsTimer.cancel();
	}
	/**
	 * 
	 */
	private void refreshFeeds() {
		switch (currentFilter) {
		case ALL_UPDATES:
			showAllUpdatesFeeds();
			break;
		case CONNECTIONS:
			showOnlyConnectionsFeeds();
			break;
		case MINE:
			showOnlyMyFeeds();
			break;
		}
	}
	/**
	 * All Updates
	 */
	public void showAllUpdatesFeeds() {
		showLoader();
		resetTimer();
		newsService.getAllUpdateUserFeeds(new AsyncCallback<ArrayList<EnhancedFeed>>() {
			@Override
			public void onSuccess(ArrayList<EnhancedFeed> feeds) {
				newsPanel.clear();
				if (feeds != null) {
					if (feeds.size() == 0) { 
						newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
								"Looks like we've got nothing for you at the moment. <br> " +
								"You may begin by <a class=\"vrelink\" href=\"/group/data-e-infrastructure-gateway/join-new/\"><span class=\"important\">joining</span></a> some of the available " +
								"<br>Virtual Research Environments.</div>"));
						isFirstTweet = true;
					}
					else {
						newsPanel.setHeight("");
						newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_LEFT);
						newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_TOP);
						for (EnhancedFeed feed : feeds) 
							newsPanel.add(new TweetTemplate(myUserInfo, feed, eventBus));
						if (feeds.size() < 5) {
							newsPanel.add(new Image(spacer));
						}
						isFirstTweet = false;
					}
				} else {
					showProblems();
				}

			}

			@Override
			public void onFailure(Throwable caught) {
				newsPanel.clear();
				newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
						"Ops! There were problems while retrieving your feeds!. <br> " +
						"Please try again in a short while.</div>"));
			}
		});
	}
	
	/**
	 * Only User Connections
	 */
	public void showOnlyConnectionsFeeds() {
		showLoader();
		resetTimer();
		newsService.getOnlyConnectionsUserFeeds(new AsyncCallback<ArrayList<EnhancedFeed>>() {
			@Override
			public void onSuccess(ArrayList<EnhancedFeed> feeds) {
				if (feeds != null) {
					newsPanel.clear();
					if (feeds.size() == 0) { 
						//TODO: provide actual link for Making some friends
						newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
								"Looks like we've got nothing for you at the moment. <br> " +
								"You may begin by <strong>adding</strong> some friend!</div>"));
						isFirstTweet = true;
					}
					else {
						newsPanel.setHeight("");
						newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_LEFT);
						newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_TOP);
						for (EnhancedFeed feed : feeds) 
							newsPanel.add(new TweetTemplate(myUserInfo, feed, eventBus));
						if (feeds.size() < 5) {
							newsPanel.add(new Image(spacer));
						}
						isFirstTweet = false;
					}
				} else
					showProblems();				

			}

			@Override
			public void onFailure(Throwable caught) {
				loadingImage.setUrl(warning);				
				newsPanel.add(new HTML("Ops! There were problems while retrieving your feeds! Please try again in a short while"));
			}
		});
	}
	/**
	 * Only User Feeds
	 */
	public void showOnlyMyFeeds() {
		showLoader();
		resetTimer();
		newsService.getOnlyMyUserFeeds(new AsyncCallback<ArrayList<EnhancedFeed>>() {
			@Override
			public void onSuccess(ArrayList<EnhancedFeed> feeds) {
				if (feeds != null) {
					newsPanel.clear();
					if (feeds.size() == 0) { 
						newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
								"Looks like we've got nothing for you at the moment. <br> " +
								"You may begin by <strong>sharing</strong> an update!</div>"));
						isFirstTweet = true;
					}
					else {
						newsPanel.setHeight("");
						newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_LEFT);
						newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_TOP);
						for (EnhancedFeed feed : feeds) 
							newsPanel.add(new TweetTemplate(myUserInfo, feed, eventBus));
						if (feeds.size() < 5) {
							newsPanel.add(new Image(spacer));
						}
						isFirstTweet = false;
					}
				} else
					showProblems();		

			}

			@Override
			public void onFailure(Throwable caught) {
				loadingImage.setUrl(warning);				
				newsPanel.add(new HTML("Ops! There were problems while retrieving your feeds! Please try again in a short while"));
			}
		});
	}
	/**
	 * Only User Liked Feeds
	 */
	public void showOnlyLikedFeeds() {
		showLoader();
		resetTimer();
		newsService.getOnlyLikedFeeds(new AsyncCallback<ArrayList<EnhancedFeed>>() {
			@Override
			public void onSuccess(ArrayList<EnhancedFeed> feeds) {
				if (feeds != null) {
					newsPanel.clear();
					if (feeds.size() == 0) { 
						newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
								"Looks like we've got nothing for you at the moment. <br> " +
								"Set an update as your <strong>favorite</strong> to see it here</div>"));
						isFirstTweet = true;
					}
					else {
						newsPanel.setHeight("");
						newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_LEFT);
						newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_TOP);
						for (EnhancedFeed feed : feeds) 
							newsPanel.add(new TweetTemplate(myUserInfo, feed, eventBus));
						if (feeds.size() < 5) {
							newsPanel.add(new Image(spacer));
						}
						isFirstTweet = false;
					}
				} else
					showProblems();		

			}

			@Override
			public void onFailure(Throwable caught) {
				loadingImage.setUrl(warning);				
				newsPanel.add(new HTML("Ops! There were problems while retrieving your feeds! Please try again in a short while"));
			}
		});
	}
	
	/**
	 * used when addin directly a feed from the UI (IPC)
	 * @param userid
	 * @param fullName
	 * @param thumbURL
	 * @param description
	 */
	public void addJustAddedFeed(ClientFeed cFeed) {
		Feed feed = new Feed(cFeed.getKey(), FeedType.SHARE, cFeed.getUserid(), null, "", cFeed.getUri(), cFeed.getLinkUrlThumbnail(), 
				cFeed.getDescription(), PrivacyLevel.CONNECTION, cFeed.getFullName(),
				cFeed.getEmail(), cFeed.getThumbnailURL(), cFeed.getLinkTitle(), cFeed.getLinkDescription(), cFeed.getLinkHost());
		EnhancedFeed toAdd = new EnhancedFeed(feed, false, true); //false cuz he could not have liked this yet and true because is the current user's 
	
		final TweetTemplate tt = new TweetTemplate(myUserInfo, toAdd, eventBus, true);
		if (isFirstTweet) {
			newsPanel.clear();
			newsPanel.add(new Image(spacer));
			isFirstTweet = false;
		}
		newsPanel.insert(tt, 0);
		Timer t = new Timer() {

			@Override
			public void run() {
				tt.setcontentAreaStyle("visible");

			}
		};

		t.schedule(500);
	}

	private void showLoader() {
		newsPanel.clear();
		newsPanel.setWidth("100%");
		newsPanel.setHeight("300px");
		newsPanel.setHorizontalAlignment(HasAlignment.ALIGN_CENTER);
		newsPanel.setVerticalAlignment(HasVerticalAlignment.ALIGN_MIDDLE);
		newsPanel.add(loadingImage);
	}
	
	private void showProblems() {
		newsPanel.clear();
		newsPanel.add(new HTML("<div class=\"nofeed-message\">" +
				"Ops! There were problems while retrieving your feeds!. <br> " +
				"Looks like we are not able to communicate with the infrastructure, <br> please try again in a short while.</div>"));
	}

	private void doAddLike(final TweetTemplate owner, final String feedId) {
		newsService.like(feedId, owner.getMyFeedText(), owner.getMyFeedUserId(), new AsyncCallback<Boolean>() {
			@Override
			public void onFailure(Throwable caught) {}
			@Override
			public void onSuccess(Boolean result) {	}
		});		
	}

	private void doShowLikes(final String feedId) {
		GWT.runAsync(new RunAsyncCallback() {
			@Override
			public void onSuccess() {
				final LikesDialog dlg = new LikesDialog();
				dlg.center();
				dlg.show();			
				newsService.getAllLikesByFeed(feedId, new AsyncCallback<ArrayList<Like>>() {
					@Override
					public void onFailure(Throwable caught) {
						Window.alert("People who liked this could not be retrieved: " + caught.getMessage());
					}

					@Override
					public void onSuccess(ArrayList<Like> result) {
						dlg.showLikes(result);
					}
				});
			}
			public void onFailure(Throwable reason) {
				Window.alert("Could not load this component: " + reason.getMessage());
			}   
		});
		
	}

	private void doAddComment(final TweetTemplate owner, String text) {
		newsService.comment(owner.getFeedKey(), text, owner.getMyFeedUserId(), new AsyncCallback<Comment>() {
			@Override
			public void onFailure(Throwable caught) {
				Window.alert("Could not deliver this comment: " + caught.getMessage());
			}
			@Override
			public void onSuccess(Comment result) {
				if (result != null) {
					owner.addComment(new SingleComment(result, owner, (result.getUserid().equals(myUserInfo.getUsername())) ));
					owner.setCommentingDisabled(false);
					owner.updateCommentsNumberCount();
				}
				else {
					Window.alert("Could not deliver this comment. Please try again in a short while.");
				}
			}
		});
	}

	private void doEditComment(final TweetTemplate owner, Comment edited) {
		newsService.editComment(edited, new AsyncCallback<Comment>() {
			@Override
			public void onFailure(Throwable caught) {
				Window.alert("Could not edit this comment: " + caught.getMessage());
			}

			@Override
			public void onSuccess(Comment result) {
				if (result != null) {
					owner.addComment(new SingleComment(result, owner, (result.getUserid().equals(myUserInfo.getUsername())) ));
					owner.setCommentingDisabled(false);
				}
				else {
					Window.alert("Could not deliver this comment. Please try again in a short while.");
				}	
			}
		});


	}

	private void doShowComments(final TweetTemplate owner, final boolean commentForm2Add) {
		owner.showLoadingComments();
		newsService.getAllCommentsByFeed(owner.getFeedKey(), new AsyncCallback<ArrayList<Comment>>() {

			@Override
			public void onFailure(Throwable caught) {
				Window.alert("Comments could not be retrieved: " + caught.getMessage());				
			}

			@Override
			public void onSuccess(ArrayList<Comment> comments) {
				owner.clearComments();
				for (Comment comment :comments) 
					owner.addComment(new SingleComment(comment, owner,(comment.getUserid().equals(myUserInfo.getUsername())) ));					
				owner.setCommentsFetched(true);
				if (commentForm2Add)
					owner.showAddCommentForm();
				owner.updateCommentsNumberCount();
			}
		});

	}


	protected void doDeleteComment(final TweetTemplate owner, String commentId) {
		newsService.deleteComment(commentId, owner.getFeedKey(), new AsyncCallback<Boolean>() {
			@Override
			public void onFailure(Throwable caught) {
				Window.alert("Comment could not be deleted: " + caught.getMessage());	

			}
			@Override
			public void onSuccess(Boolean result) {
				if (result) {
					doShowComments(owner, false);
					owner.updateCommentsNumberCount();
				} else
					Window.alert("Comment could not be deleted, please try again in a short while.");	
			}
		});

	}

	private void doDeleteFeed(final TweetTemplate toDelete) {
		if (Window.confirm("Are you sure you want to delete this feed?")) {
			newsService.deleteFeed(toDelete.getFeedKey(), new AsyncCallback<Boolean>() {

				@Override
				public void onFailure(Throwable caught) {
					Window.alert("Feed could not be deleted: " + caught.getMessage());					
				}

				@Override
				public void onSuccess(Boolean result) {
					if (result) {
						toDelete.removeFromParent();
					} else
						Window.alert("Feed could not be deleted, please try again in a short while.");	
				}
			});
		}		
	}

	/**
	 * set the filter type status for automatic reloading of tweets
	 * @param currentFilter
	 */
	public void setCurrentFilter(FilterType currentFilter) {
		this.currentFilter = currentFilter;
	}

}