1use crate::{
 2    geometry::{
 3        rect::RectF,
 4        vector::{vec2f, Vector2F},
 5    },
 6    json::{json, ToJson},
 7    DebugContext,
 8};
 9use crate::{
10    AfterLayoutContext, Element, Event, EventContext, LayoutContext, PaintContext, SizeConstraint,
11};
12
13pub struct Empty;
14
15impl Empty {
16    pub fn new() -> Self {
17        Self
18    }
19}
20
21impl Element for Empty {
22    type LayoutState = ();
23    type PaintState = ();
24
25    fn layout(
26        &mut self,
27        constraint: SizeConstraint,
28        _: &mut LayoutContext,
29    ) -> (Vector2F, Self::LayoutState) {
30        let x = if constraint.max.x().is_finite() {
31            constraint.max.x()
32        } else {
33            constraint.min.x()
34        };
35        let y = if constraint.max.y().is_finite() {
36            constraint.max.y()
37        } else {
38            constraint.min.y()
39        };
40
41        (vec2f(x, y), ())
42    }
43
44    fn after_layout(&mut self, _: Vector2F, _: &mut Self::LayoutState, _: &mut AfterLayoutContext) {
45    }
46
47    fn paint(
48        &mut self,
49        _: RectF,
50        _: &mut Self::LayoutState,
51        _: &mut PaintContext,
52    ) -> Self::PaintState {
53    }
54
55    fn dispatch_event(
56        &mut self,
57        _: &Event,
58        _: RectF,
59        _: &mut Self::LayoutState,
60        _: &mut Self::PaintState,
61        _: &mut EventContext,
62    ) -> bool {
63        false
64    }
65
66    fn debug(
67        &self,
68        bounds: RectF,
69        _: &Self::LayoutState,
70        _: &Self::PaintState,
71        _: &DebugContext,
72    ) -> serde_json::Value {
73        json!({
74            "type": "Empty",
75            "bounds": bounds.to_json(),
76        })
77    }
78}