use specs::{Component, VecStorage, NullStorage};

pub fn register(world: &mut specs::World) {
    world.register::<Position>();
    world.register::<Velocity>();
    world.register::<Sprite>();
    world.register::<Background>();
    world.register::<Foreground>();
    world.register::<Decoration>();
    world.register::<Movable>();
}

#[derive(Component, Debug)]
#[storage(VecStorage)]
pub struct Position {
    pub x: f32,
    pub y: f32,
}

impl Position {
    pub fn to_point(&self) -> ggez::nalgebra::Point2<f32> {
        ggez::nalgebra::Point2::new(self.x * 3.0, self.y * 3.0)
    }
}

#[derive(Component, Debug)]
#[storage(VecStorage)]
pub struct Velocity {
    pub dx: f32,
    pub dy: f32,
}

impl Velocity {
    pub fn to_point(&self) -> ggez::nalgebra::Point2<f32> {
        ggez::nalgebra::Point2::new(self.dx * 3.0, self.dy * 3.0)
    }
}

#[derive(Component, Debug)]
#[storage(VecStorage)]
pub struct Sprite {
    pub u: u8,
    pub v: u8,
}

impl Sprite {
    pub fn to_rect(&self) -> ggez::graphics::Rect {
        ggez::graphics::Rect {
            x: (1.0 / 32.0) * self.u as f32,
            y: (1.0 / 32.0) * self.v as f32,
            w: 1.0 / 32.0,
            h: 1.0 / 32.0,
        }
    }
}

#[derive(Component, Default, Debug)]
#[storage(NullStorage)]
pub struct Background;

#[derive(Component, Default, Debug)]
#[storage(NullStorage)]
pub struct Foreground;

#[derive(Component, Default, Debug)]
#[storage(NullStorage)]
pub struct Decoration;

#[derive(Component, Default, Debug)]
#[storage(NullStorage)]
pub struct Movable;