use image::GenericImageView;
use std::num::NonZeroU32;
use std::rc::Rc;
use winit::event::{Event, KeyEvent, WindowEvent};
use winit::event_loop::{ControlFlow, EventLoop};
use winit::keyboard::{Key, NamedKey};
use winit::window::WindowBuilder;

fn main() {
    //see fruit.jpg.license for the license of fruit.jpg
    let fruit = image::load_from_memory(include_bytes!("fruit.jpg")).unwrap();

    let event_loop = EventLoop::new().unwrap();
    let window = Rc::new(
        WindowBuilder::new()
            .with_inner_size(winit::dpi::PhysicalSize::new(fruit.width(), fruit.height()))
            .build(&event_loop)
            .unwrap(),
    );

    #[cfg(target_arch = "wasm32")]
    {
        use winit::platform::web::WindowExtWebSys;

        web_sys::window()
            .unwrap()
            .document()
            .unwrap()
            .body()
            .unwrap()
            .append_child(&window.canvas().unwrap())
            .unwrap();
    }

    let context = softbuffer::Context::new(window.clone()).unwrap();
    let mut surface = softbuffer::Surface::new(&context, window.clone()).unwrap();

    event_loop
        .run(move |event, elwt| {
            elwt.set_control_flow(ControlFlow::Wait);

            match event {
                Event::WindowEvent {
                    window_id,
                    event: WindowEvent::RedrawRequested,
                } if window_id == window.id() => {
                    surface
                        .resize(
                            NonZeroU32::new(fruit.width()).unwrap(),
                            NonZeroU32::new(fruit.height()).unwrap(),
                        )
                        .unwrap();

                    let mut buffer = surface.buffer_mut().unwrap();
                    let width = fruit.width() as usize;
                    for (x, y, pixel) in fruit.pixels() {
                        let red = pixel.0[0] as u32;
                        let green = pixel.0[1] as u32;
                        let blue = pixel.0[2] as u32;

                        let color = blue | (green << 8) | (red << 16);
                        buffer[y as usize * width + x as usize] = color;
                    }

                    buffer.present().unwrap();
                }
                Event::WindowEvent {
                    event:
                        WindowEvent::CloseRequested
                        | WindowEvent::KeyboardInput {
                            event:
                                KeyEvent {
                                    logical_key: Key::Named(NamedKey::Escape),
                                    ..
                                },
                            ..
                        },
                    window_id,
                } if window_id == window.id() => {
                    elwt.exit();
                }
                _ => {}
            }
        })
        .unwrap();
}