# Cursive

Cursive is a ncurses-based TUI (Text User Interface) library for rust. It is based on jeaye's [ncurses-rs](https://github.com/jeaye/ncurses-rs).

It is designed to be safe and easy to use:

```
[dependencies.cursive]
git = "https://github.com/Gyscos/cursive"
```

(You will also need ncurses installed - if it isn't already, check in your package manager.)

```rust
extern crate cursive;

use cursive::Cursive;
use cursive::view::{Dialog,TextView};

fn main() {
	// Creates the cursive root - required for every application.
    let mut siv = Cursive::new();

    // Create a popup window with a button that quits the application
    siv.add_layer(Dialog::new(TextView::new("Hello Dialog!"))
                    .title("Cursive")
                    .button("Quit", |s| s.quit()));

    // Starts the event loop.
    siv.run();
}
```

![Cursive dialog example](https://raw.githubusercontent.com/Gyscos/Cursive/master/doc/cursive_example.png)

_(Colors may depend on your terminal configuration.)_

## Goals

* **Ease of use.** Simle apps should be simple. Complex apps should be manageable.
* **Linux TTY Compatibility.** Colors may suffer, and UTF-8 may be too much, but most features *must* work properly on a Linux TTY.
* **Flexibility.** This library should be able to handle simple UI scripts, complex real-time applications, or even games.
    * In particular, it tries to have enough features to recreate these kind of tools:
        * [menuconfig](http://en.wikipedia.org/wiki/Menuconfig#/media/File:Linux_x86_3.10.0-rc2_Kernel_Configuration.png)
        * [nmtui](https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Networking_Guide/sec-Configure_a_Network_Team_Using_the_Text_User_Interface_nmtui.html)

## _Non_-goals

* **Extreme performance.** This is a simple layout library, guys, not [compiz](https://www.google.com/search?q=compiz&tbm=isch) piped into [libcaca](https://www.google.com/search?q=libcaca&tbm=isch). Unless you are running it on your microwave's microcontroller, it's not going to be slow.
* **Multi-threaded UI.** Callback methods are blocking - careful what you're doing in there! Feel free to use threads on your side, though.
* **Complete ncurses equivalent.** You _can_ access the underlying ncurses window when creating your own custom views, so you can do what you want with that, but the main library will probably only use a subset of the ncurses features.

## Compatibility

First off, terminals are messy. A small set of features is standard, but beyond that, almost every terminal has its own implementation.

I mostly test VTE-based terminals (Gnome & Xfce), with the occasional Konsole and xterm checks.

### Output

* **Colors**: the basic 8-colors palette should be broadly supported. User-defined colors is not supported in the raw linux TTY, but should work in most terminals, although it's still kinda experimental.
* **UTF-8**: Currently Cursive really expects a UTF-8 locale. It may eventually get patched to support window borders on other locales, but it's not a priority.
Also, Cursive currently expects every codepoint to be a one-column character, so some things may break with exotic characters...

### Input

* The `key_codes` example can be a useful tool to see how the library reacts to various key presses.
* Keep in mind that if the terminal has shortcuts registered, they probably won't be transmitted to the app.
* UTF-8 input should work fine in a unicode-enabled terminal emulator, but raw linux TTY may be more capricious.

Here is the support table for input keys (All means Linux TTY and terminal emulators):

|                          | Key  | Shift+Key              | Ctrl+Key                   | Shift+Ctrl+Key  |
|--------------------------|:----:|:----------------------:|:--------------------------:|:---------------:|
| Letters                  | All  | All                    | All (except c,z,q,s,i,h,m) | None            |
| Numbers                  | All  | All                    | None (can crash the app)   | None            |
| Punctuation              | All  | All                    | None (can crash the app)   | None            |
| Enter, Esc               | All  | None                   | None                       | None            |
| Left, Right arrow keys   | All  | VTE+Xterm              | VTE+Xterm                  | VTE+Xterm       |
| Up, Down arrow keys      | All  | Xterm                  | VTE+Xterm                  | Xterm           |
| Ins                      | All  | None (paste clipboard) | Xterm                      | None            |
| Del                      | All  | VTE+Xterm              | VTE+Xterm                  | VTE+Xterm       |
| Home, End                | All  | Xterm                  | Xterm                      | Xterm           |
| PageUp, PageDown         | All  | None                   | Xterm                      | None            |
| Fn keys: F1-F4           | All  | None (WIP)             | None (WIP)                 | None (WIP)      |
| Fn keys: F5-F12          | All  | VTE+Xterm (WIP)        | VTE+Xterm (WIP)            | VTE+Xterm (WIP) |
| PrtScn, ScrollLock       | None | None                   | None                       | None            |
| Window, Menu             | None | None                   | None                       | None            |

## Contribute

You want to help? Great! Here is a non-exhaustive list of things you could do:

* Provide example use-case: a good idea of application for existing or new components.
* Test and reports issues: a bug won't get fixed if we don't know it's there.
* Hack the code! If you feel confident with rust, pick an issue you like and hack away!