//! What a drawing can be taken out of, and what it cannot.

use iris::core::{Remap, UiRegion, UiScalar, UiSpan};

/// A box `size` tall whose top is `rel` of the way down the window.
fn fixed(rel: f32, size: f32) -> UiRegion {
    UiRegion::new(
        UiSpan::FULL,
        UiSpan::new(UiScalar { rel, abs: 0.0 }, UiScalar { rel, abs: size }),
    )
}

#[test]
fn a_fixed_box_can_be_carried_but_not_stretched() {
    let from = fixed(0.0, 164.0);
    assert!(Remap::new(from, UiRegion::FULL).is_none());
    assert!(Remap::new(from, fixed(0.5, 164.0)).is_some());
    assert!(Remap::new(from, fixed(0.0, 98.0)).is_none());
}

#[test]
fn a_relative_box_can_be_stretched_to_any_other() {
    let remap = Remap::new(UiRegion::FULL, fixed(0.0, 98.0)).expect("relative boxes remap");
    // A part that filled the window keeps filling what replaced it, which is
    // exactly what `outside` could not say for a box of a fixed length.
    assert_eq!(remap.apply(UiRegion::FULL), fixed(0.0, 98.0));
}