module Make(Layer: Repr.PRINTER) = struct

  type point = Path.Point.t

  let mark point path =
    let open Gg.V2 in
    let point = Path.Point.get_coord point in

    let dist = 5.
    and dist' = -5. in

    let path = Layer.move_to (point - (of_tuple (dist, dist))) path
               |> Layer.line_to ( point + (of_tuple (dist, dist)))
               |> Layer.move_to (point + (of_tuple (dist', dist)))
               |> Layer.line_to ( point + (of_tuple (dist, dist')))
    in
    path


  type t =
    { path: (Layer.t)
    }

  type repr = Layer.t

  let create_path
    : 'b -> t
    = fun _ ->
      { path = Layer.create ()
      }

  let start
    : point -> point -> t -> t
    = fun p1 _ { path } ->
      let path = mark p1 path in
      { path
      }

  let line_to
    : (point * point) -> (point * point) -> t -> t
    = fun (p0, p1) _ {path} ->
      let path = Layer.move_to (Path.Point.get_coord p0) path
                 |> Layer.line_to (Path.Point.get_coord p1)
                 |> mark p1 in
      { path
      }

  let quadratic_to
    : (point * Gg.v2 * Gg.v2 * point) -> (point * Gg.v2 * Gg.v2 * point) -> t -> t
    = fun (p0, ctrl0, ctrl1, p1) _ {path} ->

      let path = Layer.move_to (Path.Point.get_coord p0) path
                 |> Layer.quadratic_to ctrl0 ctrl1 (Path.Point.get_coord p1)
                 |> mark p1 in

      { path = path }

  let stop
    : t -> t
    = fun path -> path


  let get
    : t -> Layer.t
    = fun {path; _} ->
      path

end