el_diablo/src/level_widget.rs

use ratatui::buffer::Buffer;
use ratatui::layout::Rect;
use ratatui::style::Color;
use ratatui::widgets::{StatefulWidget, Widget};

use crate::game::Game;
use crate::level::StructureElement;

const FG_BROWN: Color = Color::Rgb(186, 74, 0);

pub struct LevelWidget {}

impl LevelWidget {
    fn set_cell(&self, buf: &mut Buffer, x: u16, y: u16, symbol: &str, fg: Color, bg: Color) {
        buf.
            get_mut(x, y).
            set_symbol(symbol).
            set_bg(bg).
            set_fg(fg);
    }
}

impl StatefulWidget for LevelWidget {
    type State = Game;

    fn render(self, area: Rect, buf: &mut Buffer, state: &mut Self::State) {
        let al: u16 = area.left();
        let at: u16 = area.top();

        {
            let player = state.get_mutable_player();
            let player_pos = player.get_immutable_position();
            let player_level = player_pos.get_level();

            // draw the level elements
            for x in al..area.right() {
                for y in at..area.bottom() {
                    let level = state.get_mutable_level(player_level);
                    let level_x = (x - al) as i16;
                    let level_y = (y - at) as i16;
                    match level.get_element(level_x, level_y) {
                        (Some(structure_element), None, None) => {
                            match structure_element {
                                StructureElement::Start => {
                                    self.set_cell(buf, x, y, "α", Color::Black, Color::Gray);
                                }
                                StructureElement::End => {
                                    self.set_cell(buf, x, y, "Ω", Color::Black, Color::Gray);
                                }
                                StructureElement::Wall => {
                                    // TODO add fancy walls
                                    self.set_cell(buf, x, y, "#", FG_BROWN, Color::Gray);
                                }
                                StructureElement::Floor => {
                                    self.set_cell(buf, x, y, " ", FG_BROWN, Color::Gray);
                                }
                                StructureElement::StairDown => {
                                    self.set_cell(buf, x, y, ">", Color::Black, Color::Gray);
                                }
                                StructureElement::StairUp => {
                                    self.set_cell(buf, x, y, "<", Color::Black, Color::Gray);
                                }
                                StructureElement::Unknown => {
                                    self.set_cell(buf, x, y, "▒", Color::DarkGray, Color::Gray);
                                }
                            }
                        }
                        (_, Some(m), _) => {
                            let (s, c) = m.get_representation();
                            self.set_cell(buf, x, y, s, c, Color::Gray);
                        }
                        (_, _, Some(t)) => {
                            let (s, c) = t.get_representation();
                            self.set_cell(buf, x, y, s, c, Color::Gray);
                        }
                        (None, None, None) => {}
                    };
                }
            }
        }
        {
            let player = state.get_mutable_player();
            let player_pos = player.get_immutable_position();
            let player_x = al + player_pos.get_x() as u16;
            let player_y = at + player_pos.get_y() as u16;
            self.set_cell(buf, player_x, player_y, "8", Color::Red, Color::Gray);
        }
    }
}

impl Widget for LevelWidget {
    fn render(self, _area: Rect, _buf: &mut Buffer) {}
}