import type { Ord, Ord$GetTypeClass, Ordering } from ".";
import type { Args, Call2W, Cons, Fn } from "../../HKT";
import type { AssertOrdering, IsAny } from "../../helpers";

/**
 * Compare two {@link Ord} instances.
 *
 * Sig: `(o1: Ord, o2: Ord) => Ordering`
 *
 * Type safety is **not guaranteed** if `O1` and `O2` are not of the same construct.
 */
export type Compare<O1 extends Ord, O2 extends Ord> = AssertOrdering<
  IsAny<O2> extends true ? Ordering
  : IsAny<O1> extends true ? Ordering
  : Call2W<Ord$GetTypeClass<O1>["Compare"], O1, O2> extends infer U extends Ordering ? U
  : never
>;

/**
 * [Fn] Compare two {@link Ord} instances.
 *
 * Sig: `<O extends Cons<Ord>>(o1: O, o2: O) => Ordering`
 */
export default interface CompareFn<O extends Cons<Ord>> extends Fn<[O, O], Ordering> {
  def: ([o1, o2]: Args<this>) => Compare<typeof o1, typeof o2>;
}