simultaneous text editing - node.js

I'm trying to program a Webpage, which allows to edit a text document simultaneously.
To program something like a Chat in Node.js is not very difficult, but working on the same text makes it kinda tricky.
I thought about sending the char position and the changes characters, but if someone types something previous to the change, the change would be placed on the wrong position.
What's the best way to exchange Modifications between my clients?

You should use Socket.io to have make your Real-Time application.
I just founded a nice blog article which speaks about real time edition, see here.
It's also providing a link to the github project and to an open source online editor project.
Take a look and try to understand how they do stuff like this, good luck !

Two people cannot be manipulating the same object at the same time from a different place. You basically have two choices.
1. Let them take turns with the object
2. duplicate it if they both want it, but that doesnt sound like it would end well

Related

How to format the terminal window node is using to be in sections

I'm wanting to make an application with node have a cli interface, as it needs to be ran in a terminal. I want to split the terminal into several sections, one with some identification as to who is viewing the application, another with some other random info, a menu on the side that you can use the arrow keys to move up and down the options, a main logs section, and another that you can type, and press enter to send text in. I've drawn up a little diagram of how I want to make it: (I know this looks awful, it was made in mspaint)
I've gotten the console input part working by using the readline module, but I don't even know where to really start with designing the terminal how I want it, setting text in certain sections, etc. I've looked around at things like terminal-kit, and clci, but either they didn't seem like what I wanted, or their docs/examples were a mess.
I would prefer to do this with node only, not using another application in another language, as all of the stuff going to the console sections will be from the same node application.
I found the blessed library at https://github.com/chjj/blessed. It is based on the ncurses library (written in C, https://en.wikipedia.org/wiki/Ncurses) and it allows you to create different sections with specified heights, widths, etc. in different areas of the terminal. Very useful in theory, and you can follow the advice on the github page, clone the repo into your desktop, look into the test folder, and then run the different files ie. node test/widget-form.js to see the different types of interfaces that you can create in your terminal.
It hasn't really worked for me, because it keeps crashing on my end, but I see that there are a lot of open pull requests and that people are still trying, so it might be working for some, although I think that the usage for some "widgets" is limited. The next best thing I can recommend is either blessed-contrib or neo-blessed, the former being developed by some dude from Facebook. Blessed-contrib is newer so you might have more luck with it, but it's essentially made for visual output, so you'd be able to create a section for a log, a selection menu, a paragraph section, etc. but nothing to create an area where you can input text (so 4/5 of what you need), based on my reading of the documentation, which you'll find here https://github.com/yaronn/blessed-contrib.
I personally think it's dope. Good luck with it, I'm going through the motions of understanding the documentation better myself, and I've delved pretty deeply in it, so feel free to reach out if you need any help.
On another note, let me know if you've found anything else other than the resources I mentioned, which would be very helpful for me, as the alternative right now is for me to code the text user interface myself using C and the ncurses library, which I'm trying to avoid if it's unnecessary :)
EDIT:
I found something for you and for me that might send us in the right direction. Good news. This is the gitter-cli. It uses the library I mentioned above blessed. If you clone the gitter-cli's repo, follow the instructions to get a token and create an account, and join one of the rooms (you can find the name of the rooms like 'gitterHQ/javascript' on the gitter.im website), you'll see that the chat works. There might be some optimizations I'm not aware of, but I recommend just delving into their code while also delving into the blessed documentation to understand how it works. It should give you an idea of what to do next.
It took me a lot of hours to find all these different resources and connect the dots so you should definitely check them out.

Libraries for text manipulation

So...
I plan on doing an animation that pulls all the text from the screen to the middle and lets it pulse like a heart. For that I checked if I'm able to manipulate whole Strings and Chars the way I'm able to manipulate circles, for example. I found the libraries Nexttext and Fontastic, but those seem to be outdated, therefore I can't use them with Processing 3.0. Than there is the library Geomerative, which I manged to install through Processings library manager, but this one yields the error "duplicate libraries", which I can't find a , for me understandable, workaround for. I'm also using minim, since I combine the pulse with music input, minim works fine though.
Thus I'm asking if anyone here has an idea on how to fix this error, make the outdated libraries run or maybe someone has an alternative way/library to manipulate text.
Apparently the processing forum is not that active, hence I'm asking here, there was one suggestions tho, that I should search for similar Java libraries, which I yet have to do.
What exactly do you mean when you say you want to pull text from the screen? Do you mean you want to get text from another application and copy it into Processing? Or are you just talking about doing something inside the Processing window?
If you're just talking about manipulating text within the Processing window, then I'm not sure why you need a library for this. Processing has several functions that allow you to draw text, change its font, size, positioning, etc.
Anyway, the issue you've encountered is a known bug. Looks like the only solution for now is to use an old version of Processing. You can download them from the same place you downloaded Processing 3.
Both Geomerative and Fontastic work with Processing 3.2.3
Bare in mind is the bug Kevin mentioned.
However, the only issue I had was compiling examples that had this line:
import processing.opengl.*;
Simply remove or comment this line and the example should compile

real time refreshing in processing

I am new to processing, i found it by searching for "draw with coding" , and i tried it, seems every time i modify the code, i have to stop and render again to get the final result
Is there any way to get updated graph without re-rendering? that can be much more convenient for creating simple figures.
if not, is there any alternative to processing that can draw a graph with coding?
I've used Tikz in Latex, but that is just for Latex, I want something that can let me draw a figure by coding, I've suffered enough though using software like coreldraw, it lacks the fundamental elegance of coding..
thanks alot!
Please have a look at the FluidForms libraries.
easy to setup
documentation and video tutorials
as long as you don't run into exceptions, live code comfortably
if you prefix public variables with param you also get sliders for free :)
Do check out the video tutorials, especially this one:
Also, if using Python isn't a problem I recommend having a look at:
NodeBox
Field
Python is a brilliant scripting language - which makes prototyping/'live coding' easy(although it can be compiled and it also plays nicely with c/c++) and is easy to pick up and a joy to use.
In Processing, you must re-run your program to see the changes (graphically), unless you write code to receive input from the user to dynamically adjust what you are drawing. For creating user interfaces there's for example the controlP5 library (http://www.sojamo.de/libraries/controlP5/).
It doesn't support "live coding" (at least that I know of).
You must re-run the code to see the new result.
If Live coding is what you're looking for, check out Fluxus (http://www.pawfal.org/fluxus/) or Impromptu (http://en.wikipedia.org/wiki/Impromptu_(programming_environment)

online trading bot

I want to code a trading bot for Magic: The Gathering Online. This bot should wait until someone offers to trade, accept, look through the cards available from the other trader (the information is shown on screen), and perform other similar functions. I have several questions:
How can it know that someone is offering a trade?
How can it know that the other trader has some card (the informaion is stored in pictures)?
I just cannot imagine right now how to do it, I have no experience with it, until now I've been coding only console programs for my physics neсessities.
First, you should note that some online games forbid bots, as they can give certain players unfair advantages. The MTGO Terms of Service do not seem to say anything about this, though they do put restrictions on anything that might negatively impact the service. They have also said that there is a possibility they will add an API in the future, so they don't seem to be against the idea of automation, but are not supporting it at the moment. Tread carefully here, but it looks like it should be OK to write a bot as long as it is not harmful or abusive. This is not legal advice, and it would be a good idea to ask the folks who run MTGO for permission. edit since I wrote this, it has been pointed out that there are lots of bots already, so there should be no problems writing bots.
Assuming that it is not forbidden by the terms of service, but they do not have an API, you will have to find a way to detect what's going on, and control the game automatically. There's a pretty good series of articles on writing poker bots (archived copy), which has some good information on how to inject a DLL into an application, scrape the screen, and control the application. That might provide you with a starting point for doing this sort of thing.
You might also want to look for tools that other people have already written for doing this. It looks like there are several existing MTGO bots, but they all seem a bit sketchy (there have been some reports of them stealing passwords), so be careful there.
Edit
Since this answer still seems to be getting upvotes, I should probably update it with some more useful information. Since writing this, I have found a great UI automation system called Sikuli. It allows you to write programs in Python that automate a GUI. It includes image recognition features which make it very easy to recognize buttons, cards, and other UI elements; you just take a screenshot, crop it down to include just the thing you're interested in, and do fuzzy image matching (so that changing backgrounds and the like doesn't cause the match to fail). It even includes a custom IDE that allows you to embed those screenshots directly in your source code, so you can see exactly what the code is looking for. Here's an example from the documentation (apologies for the code formatting, doing images inline in code is not easy given StackOverflow's restricted subset of HTML):
def resizeApp(app, dx, dy):
switchApp(app)
corner = find(Pattern().targetOffset(3,14))
drop_point = corner.getTarget().offset(dx, dy)
dragDrop(corner, drop_point)
resizeApp("Safari", 50, 50)
This is much easier to get started with than the techniques mentioned in the article linked above, of injecting a DLL into the process you are debugging. Sikuli runs entirely at the UI level, so you never have to modify the program you are automating or worry about changes to the internals breaking your script.
One thing it is a bit poor at is handling text; it has OCR features, but they aren't all that good. If the text is selectable, however, you can select the text, copy it, and then look directly at the clipboard.
If I were to write a bot to automate something without a good API or text-based interface, Sikuli is probably the first tool I would reach for.
This answer is constructed from my comments.
What you are trying to do is hard, any way you try and do it.
Arguably the easiest way to do it is to totally mimic the user. So the application presses buttons, moves the mouse etc. The downside with this is that it is dependant on being able to recognise the screen.
This is easier if you can alter the games files as you can then just skin ( changing the image (texture)) the required cards to a single unique colour.
The major down side is you have to have the game as the top level window or have the game running in a virtual machine. Neither of which is ideal.
Another method is to read the processes memory. You may be able to find a list of memory locations, which would make things simpler, otherwise it involves a lot of hardwork, a debugger to deduce the memory addresses. It also helps (a lot) to be able to understand assembly.
The third method is to intercept the packets, and alter them. This is easier that the method above as it (at least for me) is easier to reverse engine the protocol as you have less information to deal with. It is just a matter of setting up a packet sniffer and preforming a action with one variable different (for example, the card) and comparing the differences.
The thing you need to check are that you are not breaking the EULA. I don't know how the game works, but most of the games I have come across have a EULA that prohibits (i.e. You get banned) doing any of the things I have mentioned.

Anyone seen good embedded help in a web application?

I have a pretty simple app on the web (written in Flex) which is very straightforward to use once it has data inside it. The steps to get data inside it are themselves also pretty simple, but not at all obvious to my audience when they first log into my app.
I have been wrestling with how to communicate the data setup process to my users without referring them to a separate help. I also don't want to clog my lovely, elegant UI (which has uniformly been praised for its clarity from my current users and matches their processes very well) with wizards, or worse still an annoying animated paperclip.
I have a very rich set of tools available for the web UI but I am looking for inspiration and wondered if anyone had experienced good web-based, intuitive, unobtrusive, genuinely helpful process/usage instructions embedded in an application and could point me to a link so I can take a look for myself.
Failing that anyone got any bright ideas? There are about 5 steps involved each one visiting a different page of the existing app to enter/upload data.
Have you taken a look at:
http://www.askthecssguy.com/2007/03/form_field_hints_with_css_and.html
I believe there is a jquery or prototype or mootools or whatever framework that goes a couple steps beyond the above and walks a user through what to do. My google-fu isn't coming through right now so I can't seem to find it.
You could display the links to the data setup pages in a small strip on your main page like this (pardon the ugliness - this is just a usability idea):
alt text http://www.freeimagehosting.net/uploads/052b13acb7.jpg
The steps they've already completed are greyed out (I assume they don't have to complete these steps in sequence). When they mouse over a step they get a brief description, and then full details when they click through to the actual step page. You could have descriptive icons for each step instead of hyperlinks, of course.

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