Initial Commit

src/main.rs

@@ -0,0 +1,153 @@
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, EventStream},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use ratatui::{prelude::*, widgets::*};
+use rumqttc::{AsyncClient, MqttOptions, QoS};
+use std::{io, time::Duration};
+use tokio::sync::mpsc;
+use tokio_stream::StreamExt;
+use rand::Rng;
+
+struct App {
+    messages: Vec<String>,
+    input: String,
+    username: String,
+}
+
+impl App {
+    fn new(username: String) -> App {
+        App {
+            messages: Vec::new(),
+            input: String::new(),
+            username,
+        }
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // generate random username
+    let mut rng = rand::thread_rng();
+    let random_number = rng.gen_range(1..=999);
+    let username = format!("User{}", random_number);
+
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    // create app and run it
+    let app = App::new(username);
+    let res = run_app(&mut terminal, app).await;
+
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{err:?}");
+    }
+
+    Ok(())
+}
+
+async fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
+    let (tx, mut rx) = mpsc::channel::<String>(100);
+
+    let mut mqttoptions = MqttOptions::new(app.username.clone(), "172.16.0.3", 1883);
+    mqttoptions.set_keep_alive(Duration::from_secs(5));
+
+    let (client, mut eventloop) = AsyncClient::new(mqttoptions, 10);
+    client.subscribe("chat/msg", QoS::AtMostOnce).await.unwrap();
+
+    let client_clone = client.clone();
+
+    tokio::spawn(async move {
+        while let Ok(notification) = eventloop.poll().await {
+            if let rumqttc::Event::Incoming(rumqttc::Packet::Publish(p)) = notification {
+                let message = String::from_utf8_lossy(&p.payload).to_string();
+                if tx.send(message).await.is_err() {
+                    break;
+                }
+            }
+        }
+    });
+
+    let mut reader = EventStream::new();
+
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        tokio::select! {
+            Some(Ok(event)) = reader.next() => {
+                if let Event::Key(key) = event {
+                    match key.code {
+                        KeyCode::Enter => {
+                            let message = app.input.drain(..).collect::<String>();
+                            if message.starts_with("/nick ") {
+                                let new_username = message.split_whitespace().nth(1).unwrap_or(&app.username).to_string();
+                                app.username = new_username;
+                                app.messages.push(format!("Username changed to: {}", app.username));
+                            } else {
+                                let formatted_message = format!("{}: {}", app.username, message);
+                                client_clone
+                                    .publish("chat/msg", QoS::AtMostOnce, false, formatted_message.as_bytes())
+                                    .await
+                                    .unwrap();
+                            }
+                        }
+                        KeyCode::Char(c) => {
+                            app.input.push(c);
+                        }
+                        KeyCode::Backspace => {
+                            app.input.pop();
+                        }
+                        KeyCode::Esc => {
+                            return Ok(());
+                        }
+                        _ => {}
+                    }
+                }
+            }
+            Some(message) = rx.recv() => {
+                app.messages.push(message);
+            }
+            else => {
+                break;
+            }
+        }
+    }
+
+    Ok(())
+}
+
+fn ui(f: &mut Frame, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(1)
+        .constraints([Constraint::Percentage(80), Constraint::Percentage(20)].as_ref())
+        .split(f.size());
+
+    let messages: Vec<ListItem> = app
+        .messages
+        .iter()
+        .map(|m| ListItem::new(m.as_str()))
+        .collect();
+    let messages = List::new(messages)
+        .block(Block::default().borders(Borders::ALL).title("Messages"));
+    f.render_widget(messages, chunks[0]);
+
+    let input = Paragraph::new(app.input.as_str())
+        .style(Style::default())
+        .block(Block::default().borders(Borders::ALL).title("Input"));
+    f.render_widget(input, chunks[1]);
+}