use cairo::{Context, FontFace, Format, ImageSurface, LineCap, Pattern};
use glib::Object;
use gtk::{prelude::*, subclass::prelude::*};
use std::{cell::RefCell, rc::Rc};

const WIDTH: i32 = 800;
const HEIGHT: i32 = 800;

pub struct SplashPrivate {
    text: Rc<RefCell<String>>,
    time: Rc<RefCell<String>>,
    background: Rc<RefCell<Pattern>>,
}

impl SplashPrivate {
    fn set_text(&self, text: String) {
        *self.text.borrow_mut() = text;
    }

    fn set_time(&self, time: String) {
        *self.time.borrow_mut() = time;
    }

    fn redraw_background(&self) {
        let background = ImageSurface::create(Format::Rgb24, WIDTH, HEIGHT).unwrap();
        let context = Context::new(background).unwrap();
        context.push_group();
        context.set_source_rgb(0., 0., 0.);
        let _ = context.paint();

        context.set_font_size(64.);

        let title_extents = context.text_extents(&self.text.borrow()).unwrap();

        context.set_source_rgb(0.7, 0., 1.);
        context.set_line_width(5.);
        context.set_line_cap(LineCap::Round);
        AsymLineReturn {
            orientation: gtk::Orientation::Horizontal,
            start_x: 20.,
            start_y: 20.,
            start_length: 200.,
            center_length: title_extents.y_advance(),
            end_length: 100.,
            width: title_extents.height(),
        }
        .draw(&context);
        let _ = context.stroke();

        let background = context.pop_group().unwrap();

        *self.background.borrow_mut() = background;
    }
}

#[glib::object_subclass]
impl ObjectSubclass for SplashPrivate {
    const NAME: &'static str = "Splash";
    type Type = Splash;
    type ParentType = gtk::DrawingArea;

    fn new() -> SplashPrivate {
        // Set up a default plain black background
        let background = ImageSurface::create(Format::Rgb24, WIDTH, HEIGHT).unwrap();
        let context = Context::new(background).unwrap();
        context.push_group();
        context.set_source_rgb(0., 0., 0.);
        let _ = context.paint();
        let background = context.pop_group().unwrap();

        SplashPrivate {
            text: Rc::new(RefCell::new(String::from(""))),
            time: Rc::new(RefCell::new(String::from(""))),
            background: Rc::new(RefCell::new(background)),
        }
    }
}
impl ObjectImpl for SplashPrivate {}
impl WidgetImpl for SplashPrivate {}
impl DrawingAreaImpl for SplashPrivate {}

glib::wrapper! {
    pub struct Splash(ObjectSubclass<SplashPrivate>) @extends gtk::DrawingArea, gtk::Widget;
}

impl Splash {
    pub fn new(text: String, time: String) -> Self {
        let s: Self = Object::builder().build();
        s.set_width_request(WIDTH);
        s.set_height_request(HEIGHT);

        s.imp().set_text(text);
        s.imp().set_time(time);
        s.imp().redraw_background();

        s.set_draw_func({
            let s = s.clone();
            move |_, context, _width, _height| {
                let background = s.imp().background.borrow();
                let _ = context.set_source(&*background);
                let _ = context.paint();
            }
        });

        s
    }
}

struct AsymLineReturn {
    orientation: gtk::Orientation,
    start_x: f64,
    start_y: f64,
    start_length: f64,
    center_length: f64,
    end_length: f64,
    width: f64,
}

impl AsymLineReturn {
    fn draw(&self, context: &Context) {
        match self.orientation {
            gtk::Orientation::Horizontal => {
                context.move_to(self.start_x, self.start_y);
                context.line_to(self.start_x + self.start_length, self.start_y);
                context.line_to(
                    self.start_x + self.start_length + self.width.abs(),
                    self.start_y + self.width,
                );
                context.line_to(
                    self.start_x + self.start_length + self.width.abs() + self.center_length,
                    self.start_y + self.width,
                );
                context.line_to(
                    self.start_x
                        + self.start_length
                        + self.width.abs()
                        + self.center_length
                        + (self.width.abs() / 2.),
                    self.start_y + self.width / 2.,
                );
                context.line_to(
                    self.start_x
                        + self.start_length
                        + self.width.abs()
                        + self.center_length
                        + (self.width.abs() / 2.)
                        + self.end_length,
                    self.start_y + self.width / 2.,
                );
            }
            gtk::Orientation::Vertical => {
                context.move_to(self.start_x, self.start_y);
                context.line_to(self.start_x, self.start_y + self.start_length);
                context.line_to(
                    self.start_x + self.width,
                    self.start_y + self.start_length + self.width.abs(),
                );
                context.line_to(
                    self.start_x + self.width,
                    self.start_y + self.start_length + self.width.abs() + self.center_length,
                );
                context.line_to(
                    self.start_x + self.width / 2.,
                    self.start_y
                        + self.start_length
                        + self.width.abs()
                        + self.center_length
                        + (self.width.abs() / 2.),
                );
                context.line_to(
                    self.start_x + self.width / 2.,
                    self.start_y
                        + self.start_length
                        + self.width.abs()
                        + self.center_length
                        + (self.width.abs() / 2.)
                        + self.end_length,
                );
            }
            _ => panic!("unknown orientation"),
        }
    }
}

fn main() {
    let app = gtk::Application::builder()
        .application_id("com.luminescent-dreams.cyberpunk-splash")
        .build();

    app.connect_activate(move |app| {
        let window = gtk::ApplicationWindow::new(app);
        window.present();

        window.set_child(Some(&Splash::new("Kifu".to_owned(), "4:23".to_owned())));
    });

    app.run();
}