use tek::*;
use tek_edn::*;
use std::sync::{Arc, RwLock};
use crossterm::event::{*, KeyCode::*};

const EDN: &'static [&'static str] = &[
    include_str!("edn01.edn"),
    include_str!("edn02.edn"),
    include_str!("edn03.edn"),
    include_str!("edn04.edn"),
    include_str!("edn05.edn"),
    include_str!("edn06.edn"),
    include_str!("edn07.edn"),
    include_str!("edn08.edn"),
    include_str!("edn09.edn"),
    include_str!("edn10.edn"),
];

fn main () -> Usually<()> {
    let state = Arc::new(RwLock::new(Example(4, Measure::new())));
    Tui::new().unwrap().run(&state)?;
    Ok(())
}

pub struct Example(usize, Measure<TuiOut>);

impl EdnViewData<TuiOut> for &Example {
    fn get_content <'a> (&'a self, item: EdnItem<&'a str>) -> RenderBox<'a, TuiOut> {
        use EdnItem::*;
        match item {
            Nil => Box::new(()),
            Exp(items) => Box::new(EdnView::from_items(*self, items.as_slice())),
            Sym(":title") => Tui::bg(Color::Rgb(60,10,10), Push::y(1,
                Align::n(format!("Example {}/{}:", self.0 + 1, EDN.len())))).boxed(),
            Sym(":code") => Tui::bg(Color::Rgb(10,60,10), Push::y(2,
                Align::n(format!("{}", EDN[self.0])))).boxed(),
            Sym(":hello-world") => "Hello world!".boxed(),
            Sym(":hello") => Tui::bg(Color::Rgb(10, 100, 10), "Hello").boxed(),
            Sym(":world") => Tui::bg(Color::Rgb(100, 10, 10), "world").boxed(),
            _ => panic!("no content for {item:?}")
        }
    }
}

impl Content<TuiOut> for Example {
    fn content (&self) -> impl Render<TuiOut> {
        let title   = Tui::bg(Color::Rgb(60,10,10), Push::y(1, Align::n(format!("Example {}/{} in {:?}", self.0 + 1, EDN.len(), &self.1.wh()))));
        let code    = Tui::bg(Color::Rgb(10,60,10), Push::y(2, Align::n(format!("{}", EDN[self.0]))));
        let content = Tui::bg(Color::Rgb(10,10,60), EdnView::from_source(self, EDN[self.0]));
        self.1.of(Bsp::s(title, Bsp::n(code, content)))
    }
}

impl Handle<TuiIn> for Example {
    fn handle (&mut self, input: &TuiIn) -> Perhaps<bool> {
        match input.event() {
            kpat!(Right) => self.0 = (self.0 + 1) % EDN.len(),
            kpat!(Left) => self.0 = if self.0 > 0 { self.0 - 1 } else { EDN.len() - 1 },
            _ => return Ok(None)
        }
        Ok(Some(true))
    }
}