tui-popup 0.7.4

use color_eyre::Result;
use lipsum::lipsum;
use ratatui::crossterm::event::{self, Event, KeyCode};
use ratatui::prelude::{Rect, Span, Style, Stylize, Text};
use ratatui::widgets::{Paragraph, Wrap};
use ratatui::Frame;
use tui_popup::{KnownSizeWrapper, Popup};

fn main() -> Result<()> {
    color_eyre::install()?;
    let terminal = ratatui::init();
    let result = App::default().run(terminal);
    ratatui::restore();
    result
}

#[derive(Default)]
struct App {
    should_exit: bool,
    lorem_ipsum: String,
    scroll: u16,
}

impl App {
    fn run(&mut self, mut terminal: ratatui::DefaultTerminal) -> Result<()> {
        self.lorem_ipsum = lipsum(2000);
        while !self.should_exit {
            terminal.draw(|frame| self.render(frame))?;
            self.handle_events()?;
        }
        Ok(())
    }

    fn render(&self, frame: &mut Frame) {
        let area = frame.area();
        self.render_background(frame, area);
        self.render_popup(frame);
    }

    fn render_background(&self, frame: &mut Frame, area: Rect) {
        let text = Text::raw(&self.lorem_ipsum);
        let paragraph = Paragraph::new(text).wrap(Wrap { trim: false }).dark_gray();
        frame.render_widget(paragraph, area);
    }

    fn render_popup(&self, frame: &mut Frame) {
        let lines: Text = (0..10).map(|i| Span::raw(format!("Line {i}"))).collect();
        let paragraph = Paragraph::new(lines).scroll((self.scroll, 0));
        let wrapper = KnownSizeWrapper {
            inner: paragraph,
            width: 21,
            height: 5,
        };
        let popup = Popup::new(wrapper)
            .title("scroll: ↑/↓ quit: Esc")
            .style(Style::new().white().on_blue());
        frame.render_widget(popup, frame.area());
    }

    fn handle_events(&mut self) -> Result<()> {
        if let Event::Key(key) = event::read()? {
            match key.code {
                KeyCode::Char('q') | KeyCode::Esc => self.should_exit = true,
                KeyCode::Char('j') | KeyCode::Down => self.scroll_down(),
                KeyCode::Char('k') | KeyCode::Up => self.scroll_up(),
                _ => {}
            }
        }
        Ok(())
    }

    const fn scroll_up(&mut self) {
        self.scroll = self.scroll.saturating_sub(1);
    }

    const fn scroll_down(&mut self) {
        self.scroll = self.scroll.saturating_add(1);
    }
}