use tek::*;

fn main () -> Usually<()> {
    Tui::run(Arc::new(RwLock::new(Demo::new())))?;
    Ok(())
}

pub struct Demo<E: Engine> {
    index: usize,
    items: Vec<Box<dyn Render<Engine = E>>>
}

impl Demo<Tui> {
    fn new () -> Self {
        Self {
            index: 0,
            items: vec![]
        }
    }
}

impl Content for Demo<Tui> {
    type Engine = Tui;
    fn content (&self) -> dyn Render<Engine = Tui> {
        let border_style = Style::default().fg(Color::Rgb(0,0,0));
        Align::Center(Layers::new(move|add|{

            add(&Background(Color::Rgb(0,128,128)))?;

            add(&Margin::XY(1, 1, Stack::down(|add|{

                add(&Layers::new(|add|{
                    add(&Background(Color::Rgb(128,96,0)))?;
                    add(&Border(Square(border_style)))?;
                    add(&Margin::XY(2, 1, "..."))?;
                    Ok(())
                }).debug())?;

                add(&Layers::new(|add|{
                    add(&Background(Color::Rgb(128,64,0)))?;
                    add(&Border(Lozenge(border_style)))?;
                    add(&Margin::XY(4, 2, "---"))?;
                    Ok(())
                }).debug())?;

                add(&Layers::new(|add|{
                    add(&Background(Color::Rgb(96,64,0)))?;
                    add(&Border(SquareBold(border_style)))?;
                    add(&Margin::XY(6, 3, "~~~"))?;
                    Ok(())
                }).debug())?;

                Ok(())
            })).debug())?;

            Ok(())

        }))
        //Align::Center(Margin::X(1, Layers::new(|add|{
            //add(&Background(Color::Rgb(128,0,0)))?;
            //add(&Stack::down(|add|{
                //add(&Margin::Y(1, Layers::new(|add|{
                    //add(&Background(Color::Rgb(0,128,0)))?;
                    //add(&Align::Center("12345"))?;
                    //add(&Align::Center("FOO"))
                //})))?;
                //add(&Margin::XY(1, 1, Layers::new(|add|{
                    //add(&Align::Center("1234567"))?;
                    //add(&Align::Center("BAR"))?;
                    //add(&Background(Color::Rgb(0,0,128)))
                //})))
            //}))
        //})))

        //Align::Y(Layers::new(|add|{
            //add(&Background(Color::Rgb(128,0,0)))?;
            //add(&Margin::X(1, Align::Center(Stack::down(|add|{
                //add(&Align::X(Margin::Y(1, Layers::new(|add|{
                    //add(&Background(Color::Rgb(0,128,0)))?;
                    //add(&Align::Center("12345"))?;
                    //add(&Align::Center("FOO"))
                //})))?;
                //add(&Margin::XY(1, 1, Layers::new(|add|{
                    //add(&Align::Center("1234567"))?;
                    //add(&Align::Center("BAR"))?;
                    //add(&Background(Color::Rgb(0,0,128)))
                //})))?;
                //Ok(())
            //})))))
        //}))
    }
}

impl Handle<TuiIn> for Demo<Tui> {
    fn handle (&mut self, from: &TuiIn) -> Perhaps<bool> {
        use KeyCode::{PageUp, PageDown};
        match from.event() {
            kexp!(PageUp) => {
                self.index = (self.index + 1) % self.items.len();
            },
            kexp!(PageDown) => {
                self.index = if self.index > 1 {
                    self.index - 1
                } else {
                    self.items.len() - 1
                };
            },
            _ => return Ok(None)
        }
        Ok(Some(true))
    }
}

//lisp!(CONTENT Demo (LET
  //(BORDER-STYLE (STYLE (FG (RGB 0 0 0))))
  //(BG-COLOR-0   (RGB 0 128 128))
  //(BG-COLOR-1   (RGB 128 96 0))
  //(BG-COLOR-2   (RGB 128 64 0))
  //(BG-COLOR-3   (RGB 96 64 0))
  //(CENTER (LAYERS
    //(BACKGROUND BG-COLOR-0)
      //(OUTSET-XY 1 1 (SPLIT-DOWN
        //(LAYERS (BACKGROUND BG-COLOR-1)
                //(BORDER SQUARE BORDER-STYLE)
                //(OUTSET-XY 2 1 "..."))
        //(LAYERS (BACKGROUND BG-COLOR-2)
                //(BORDER LOZENGE BORDER-STYLE)
                //(OUTSET-XY 4 2 "---"))
        //(LAYERS (BACKGROUND BG-COLOR-3)
                //(BORDER SQUARE-BOLD BORDER-STYLE)
                //(OUTSET-XY 2 1 "~~~"))))))))