//! GUI drawing capabilities.

use crate::durandal::image::Color;

/// An image possibly cached into a native driver's memory.
pub trait CacheImage
{
   /// The width of the image.
   fn w(&self) -> Coord;

   /// The width of the image.
   fn h(&self) -> Coord;
}

/// A native vector drawing area.
pub trait DrawArea
{
   /// The native `CacheImage` type for this `DrawArea`.
   type NativeImage: CacheImage;

   /// The width of the entire area.
   fn w(&self) -> Coord;

   /// The height of the entire area.
   fn h(&self) -> Coord;

   /// Fills the entire screen with `cr`. Will also default all settings.
   fn clear(&mut self, cr: impl Color);

   /// Changes the width for lines. The default is `1`.
   fn line_width(&mut self, width: u8);

   /// Draws a line from `p1` to `p2` with color `cr`.
   fn line(&mut self, p1: Point, p2: Point, cr: impl Color);

   /// Draws a rectangle `rect` of color `cr`.
   fn rect(&mut self, rect: Rect, cr: impl Color);

   /// Draws the Unicode `text` at `pos` stroked with color `cr`.
   fn text(&mut self, pos: Point, text: &str, cr: impl Color);

   /// Draws `im` at `pos`, starting from the top left column.
   fn image(&mut self, pos: Point, im: &Self::NativeImage);
}

/// A type capable of representing any coordinate on any axis.
pub type Coord = i32;

/// A 2-dimensional point.
pub type Point = (Coord, Coord);

/// A 2-dimensional rectangle.
#[derive(Copy, Clone, Debug)]
pub struct Rect
{
   /// The horizontal coordinate to start at, from the left.
   pub x: Coord,

   /// The vertical coordinate to start at, from the top.
   pub y: Coord,

   /// The width of the rectangle.
   pub w: Coord,

   /// The height of the rectangle.
   pub h: Coord,
}

// EOF