1use std::{iter, mem, ops::Range};
2
3use crate::{
4 black, phi, point, quad, rems, AbsoluteLength, BorrowAppContext, BorrowWindow, Bounds,
5 ContentMask, Corners, CornersRefinement, CursorStyle, DefiniteLength, Edges, EdgesRefinement,
6 Font, FontFeatures, FontStyle, FontWeight, Hsla, Length, Pixels, Point, PointRefinement, Rgba,
7 SharedString, Size, SizeRefinement, Styled, TextRun, WindowContext,
8};
9use collections::HashSet;
10use refineable::{Cascade, Refineable};
11use smallvec::SmallVec;
12pub use taffy::style::{
13 AlignContent, AlignItems, AlignSelf, Display, FlexDirection, FlexWrap, JustifyContent,
14 Overflow, Position,
15};
16
17#[cfg(debug_assertions)]
18pub struct DebugBelow;
19
20pub type StyleCascade = Cascade<Style>;
21
22#[derive(Clone, Refineable, Debug)]
23#[refineable(Debug)]
24pub struct Style {
25 /// What layout strategy should be used?
26 pub display: Display,
27
28 /// Should the element be painted on screen?
29 pub visibility: Visibility,
30
31 // Overflow properties
32 /// How children overflowing their container should affect layout
33 #[refineable]
34 pub overflow: Point<Overflow>,
35 /// How much space (in points) should be reserved for the scrollbars of `Overflow::Scroll` and `Overflow::Auto` nodes.
36 pub scrollbar_width: f32,
37
38 // Position properties
39 /// What should the `position` value of this struct use as a base offset?
40 pub position: Position,
41 /// How should the position of this element be tweaked relative to the layout defined?
42 #[refineable]
43 pub inset: Edges<Length>,
44
45 // Size properies
46 /// Sets the initial size of the item
47 #[refineable]
48 pub size: Size<Length>,
49 /// Controls the minimum size of the item
50 #[refineable]
51 pub min_size: Size<Length>,
52 /// Controls the maximum size of the item
53 #[refineable]
54 pub max_size: Size<Length>,
55 /// Sets the preferred aspect ratio for the item. The ratio is calculated as width divided by height.
56 pub aspect_ratio: Option<f32>,
57
58 // Spacing Properties
59 /// How large should the margin be on each side?
60 #[refineable]
61 pub margin: Edges<Length>,
62 /// How large should the padding be on each side?
63 #[refineable]
64 pub padding: Edges<DefiniteLength>,
65 /// How large should the border be on each side?
66 #[refineable]
67 pub border_widths: Edges<AbsoluteLength>,
68
69 // Alignment properties
70 /// How this node's children aligned in the cross/block axis?
71 pub align_items: Option<AlignItems>,
72 /// How this node should be aligned in the cross/block axis. Falls back to the parents [`AlignItems`] if not set
73 pub align_self: Option<AlignSelf>,
74 /// How should content contained within this item be aligned in the cross/block axis
75 pub align_content: Option<AlignContent>,
76 /// How should contained within this item be aligned in the main/inline axis
77 pub justify_content: Option<JustifyContent>,
78 /// How large should the gaps between items in a flex container be?
79 #[refineable]
80 pub gap: Size<DefiniteLength>,
81
82 // Flexbox properies
83 /// Which direction does the main axis flow in?
84 pub flex_direction: FlexDirection,
85 /// Should elements wrap, or stay in a single line?
86 pub flex_wrap: FlexWrap,
87 /// Sets the initial main axis size of the item
88 pub flex_basis: Length,
89 /// The relative rate at which this item grows when it is expanding to fill space, 0.0 is the default value, and this value must be positive.
90 pub flex_grow: f32,
91 /// The relative rate at which this item shrinks when it is contracting to fit into space, 1.0 is the default value, and this value must be positive.
92 pub flex_shrink: f32,
93
94 /// The fill color of this element
95 pub background: Option<Fill>,
96
97 /// The border color of this element
98 pub border_color: Option<Hsla>,
99
100 /// The radius of the corners of this element
101 #[refineable]
102 pub corner_radii: Corners<AbsoluteLength>,
103
104 /// Box Shadow of the element
105 pub box_shadow: SmallVec<[BoxShadow; 2]>,
106
107 /// TEXT
108 pub text: TextStyleRefinement,
109
110 /// The mouse cursor style shown when the mouse pointer is over an element.
111 pub mouse_cursor: Option<CursorStyle>,
112
113 pub z_index: Option<u8>,
114
115 #[cfg(debug_assertions)]
116 pub debug: bool,
117 #[cfg(debug_assertions)]
118 pub debug_below: bool,
119}
120
121impl Styled for StyleRefinement {
122 fn style(&mut self) -> &mut StyleRefinement {
123 self
124 }
125}
126
127#[derive(Default, Clone, Copy, Debug, Eq, PartialEq)]
128pub enum Visibility {
129 #[default]
130 Visible,
131 Hidden,
132}
133
134#[derive(Clone, Debug)]
135pub struct BoxShadow {
136 pub color: Hsla,
137 pub offset: Point<Pixels>,
138 pub blur_radius: Pixels,
139 pub spread_radius: Pixels,
140}
141
142#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
143pub enum WhiteSpace {
144 #[default]
145 Normal,
146 Nowrap,
147}
148
149#[derive(Refineable, Clone, Debug)]
150#[refineable(Debug)]
151pub struct TextStyle {
152 pub color: Hsla,
153 pub font_family: SharedString,
154 pub font_features: FontFeatures,
155 pub font_size: AbsoluteLength,
156 pub line_height: DefiniteLength,
157 pub font_weight: FontWeight,
158 pub font_style: FontStyle,
159 pub background_color: Option<Hsla>,
160 pub underline: Option<UnderlineStyle>,
161 pub white_space: WhiteSpace,
162}
163
164impl Default for TextStyle {
165 fn default() -> Self {
166 TextStyle {
167 color: black(),
168 font_family: "Helvetica".into(), // todo!("Get a font we know exists on the system")
169 font_features: FontFeatures::default(),
170 font_size: rems(1.).into(),
171 line_height: phi(),
172 font_weight: FontWeight::default(),
173 font_style: FontStyle::default(),
174 background_color: None,
175 underline: None,
176 white_space: WhiteSpace::Normal,
177 }
178 }
179}
180
181impl TextStyle {
182 pub fn highlight(mut self, style: impl Into<HighlightStyle>) -> Self {
183 let style = style.into();
184 if let Some(weight) = style.font_weight {
185 self.font_weight = weight;
186 }
187 if let Some(style) = style.font_style {
188 self.font_style = style;
189 }
190
191 if let Some(color) = style.color {
192 self.color = self.color.blend(color);
193 }
194
195 if let Some(factor) = style.fade_out {
196 self.color.fade_out(factor);
197 }
198
199 if let Some(background_color) = style.background_color {
200 self.background_color = Some(background_color);
201 }
202
203 if let Some(underline) = style.underline {
204 self.underline = Some(underline);
205 }
206
207 self
208 }
209
210 pub fn font(&self) -> Font {
211 Font {
212 family: self.font_family.clone(),
213 features: self.font_features.clone(),
214 weight: self.font_weight,
215 style: self.font_style,
216 }
217 }
218
219 /// Returns the rounded line height in pixels.
220 pub fn line_height_in_pixels(&self, rem_size: Pixels) -> Pixels {
221 self.line_height.to_pixels(self.font_size, rem_size).round()
222 }
223
224 pub fn to_run(&self, len: usize) -> TextRun {
225 TextRun {
226 len,
227 font: Font {
228 family: self.font_family.clone(),
229 features: Default::default(),
230 weight: self.font_weight,
231 style: self.font_style,
232 },
233 color: self.color,
234 background_color: self.background_color,
235 underline: self.underline.clone(),
236 }
237 }
238}
239
240#[derive(Copy, Clone, Debug, Default, PartialEq)]
241pub struct HighlightStyle {
242 pub color: Option<Hsla>,
243 pub font_weight: Option<FontWeight>,
244 pub font_style: Option<FontStyle>,
245 pub background_color: Option<Hsla>,
246 pub underline: Option<UnderlineStyle>,
247 pub fade_out: Option<f32>,
248}
249
250impl Eq for HighlightStyle {}
251
252impl Style {
253 pub fn text_style(&self) -> Option<&TextStyleRefinement> {
254 if self.text.is_some() {
255 Some(&self.text)
256 } else {
257 None
258 }
259 }
260
261 pub fn overflow_mask(&self, bounds: Bounds<Pixels>) -> Option<ContentMask<Pixels>> {
262 match self.overflow {
263 Point {
264 x: Overflow::Visible,
265 y: Overflow::Visible,
266 } => None,
267 _ => {
268 let current_mask = bounds;
269 let min = current_mask.origin;
270 let max = current_mask.lower_right();
271 let bounds = match (
272 self.overflow.x == Overflow::Visible,
273 self.overflow.y == Overflow::Visible,
274 ) {
275 // x and y both visible
276 (true, true) => return None,
277 // x visible, y hidden
278 (true, false) => Bounds::from_corners(
279 point(min.x, bounds.origin.y),
280 point(max.x, bounds.lower_right().y),
281 ),
282 // x hidden, y visible
283 (false, true) => Bounds::from_corners(
284 point(bounds.origin.x, min.y),
285 point(bounds.lower_right().x, max.y),
286 ),
287 // both hidden
288 (false, false) => bounds,
289 };
290 Some(ContentMask { bounds })
291 }
292 }
293 }
294
295 pub fn apply_text_style<C, F, R>(&self, cx: &mut C, f: F) -> R
296 where
297 C: BorrowAppContext,
298 F: FnOnce(&mut C) -> R,
299 {
300 if self.text.is_some() {
301 cx.with_text_style(Some(self.text.clone()), f)
302 } else {
303 f(cx)
304 }
305 }
306
307 /// Apply overflow to content mask
308 pub fn apply_overflow<C, F, R>(&self, bounds: Bounds<Pixels>, cx: &mut C, f: F) -> R
309 where
310 C: BorrowWindow,
311 F: FnOnce(&mut C) -> R,
312 {
313 let current_mask = cx.content_mask();
314
315 let min = current_mask.bounds.origin;
316 let max = current_mask.bounds.lower_right();
317
318 let mask_bounds = match (
319 self.overflow.x == Overflow::Visible,
320 self.overflow.y == Overflow::Visible,
321 ) {
322 // x and y both visible
323 (true, true) => return f(cx),
324 // x visible, y hidden
325 (true, false) => Bounds::from_corners(
326 point(min.x, bounds.origin.y),
327 point(max.x, bounds.lower_right().y),
328 ),
329 // x hidden, y visible
330 (false, true) => Bounds::from_corners(
331 point(bounds.origin.x, min.y),
332 point(bounds.lower_right().x, max.y),
333 ),
334 // both hidden
335 (false, false) => bounds,
336 };
337 let mask = ContentMask {
338 bounds: mask_bounds,
339 };
340
341 cx.with_content_mask(Some(mask), f)
342 }
343
344 /// Paints the background of an element styled with this style.
345 pub fn paint(
346 &self,
347 bounds: Bounds<Pixels>,
348 cx: &mut WindowContext,
349 continuation: impl FnOnce(&mut WindowContext),
350 ) {
351 #[cfg(debug_assertions)]
352 if self.debug_below {
353 cx.set_global(DebugBelow)
354 }
355
356 #[cfg(debug_assertions)]
357 if self.debug || cx.has_global::<DebugBelow>() {
358 cx.paint_quad(crate::outline(bounds, crate::red()));
359 }
360
361 let rem_size = cx.rem_size();
362
363 cx.with_z_index(0, |cx| {
364 cx.paint_shadows(
365 bounds,
366 self.corner_radii.to_pixels(bounds.size, rem_size),
367 &self.box_shadow,
368 );
369 });
370
371 let background_color = self.background.as_ref().and_then(Fill::color);
372 if background_color.is_some() || self.is_border_visible() {
373 cx.with_z_index(1, |cx| {
374 cx.paint_quad(quad(
375 bounds,
376 self.corner_radii.to_pixels(bounds.size, rem_size),
377 background_color.unwrap_or_default(),
378 self.border_widths.to_pixels(rem_size),
379 self.border_color.unwrap_or_default(),
380 ));
381 });
382 }
383
384 cx.with_z_index(2, |cx| {
385 continuation(cx);
386 });
387
388 #[cfg(debug_assertions)]
389 if self.debug_below {
390 cx.remove_global::<DebugBelow>();
391 }
392 }
393
394 fn is_border_visible(&self) -> bool {
395 self.border_color
396 .map_or(false, |color| !color.is_transparent())
397 && self.border_widths.any(|length| !length.is_zero())
398 }
399}
400
401impl Default for Style {
402 fn default() -> Self {
403 Style {
404 display: Display::Block,
405 visibility: Visibility::Visible,
406 overflow: Point {
407 x: Overflow::Visible,
408 y: Overflow::Visible,
409 },
410 scrollbar_width: 0.0,
411 position: Position::Relative,
412 inset: Edges::auto(),
413 margin: Edges::<Length>::zero(),
414 padding: Edges::<DefiniteLength>::zero(),
415 border_widths: Edges::<AbsoluteLength>::zero(),
416 size: Size::auto(),
417 min_size: Size::auto(),
418 max_size: Size::auto(),
419 aspect_ratio: None,
420 gap: Size::default(),
421 // Aligment
422 align_items: None,
423 align_self: None,
424 align_content: None,
425 justify_content: None,
426 // Flexbox
427 flex_direction: FlexDirection::Row,
428 flex_wrap: FlexWrap::NoWrap,
429 flex_grow: 0.0,
430 flex_shrink: 1.0,
431 flex_basis: Length::Auto,
432 background: None,
433 border_color: None,
434 corner_radii: Corners::default(),
435 box_shadow: Default::default(),
436 text: TextStyleRefinement::default(),
437 mouse_cursor: None,
438 z_index: None,
439
440 #[cfg(debug_assertions)]
441 debug: false,
442 #[cfg(debug_assertions)]
443 debug_below: false,
444 }
445 }
446}
447
448#[derive(Refineable, Copy, Clone, Default, Debug, PartialEq, Eq)]
449#[refineable(Debug)]
450pub struct UnderlineStyle {
451 pub thickness: Pixels,
452 pub color: Option<Hsla>,
453 pub wavy: bool,
454}
455
456#[derive(Clone, Debug)]
457pub enum Fill {
458 Color(Hsla),
459}
460
461impl Fill {
462 pub fn color(&self) -> Option<Hsla> {
463 match self {
464 Fill::Color(color) => Some(*color),
465 }
466 }
467}
468
469impl Default for Fill {
470 fn default() -> Self {
471 Self::Color(Hsla::default())
472 }
473}
474
475impl From<Hsla> for Fill {
476 fn from(color: Hsla) -> Self {
477 Self::Color(color)
478 }
479}
480
481impl From<TextStyle> for HighlightStyle {
482 fn from(other: TextStyle) -> Self {
483 Self::from(&other)
484 }
485}
486
487impl From<&TextStyle> for HighlightStyle {
488 fn from(other: &TextStyle) -> Self {
489 Self {
490 color: Some(other.color),
491 font_weight: Some(other.font_weight),
492 font_style: Some(other.font_style),
493 background_color: other.background_color,
494 underline: other.underline.clone(),
495 fade_out: None,
496 }
497 }
498}
499
500impl HighlightStyle {
501 pub fn highlight(&mut self, other: HighlightStyle) {
502 match (self.color, other.color) {
503 (Some(self_color), Some(other_color)) => {
504 self.color = Some(Hsla::blend(other_color, self_color));
505 }
506 (None, Some(other_color)) => {
507 self.color = Some(other_color);
508 }
509 _ => {}
510 }
511
512 if other.font_weight.is_some() {
513 self.font_weight = other.font_weight;
514 }
515
516 if other.font_style.is_some() {
517 self.font_style = other.font_style;
518 }
519
520 if other.background_color.is_some() {
521 self.background_color = other.background_color;
522 }
523
524 if other.underline.is_some() {
525 self.underline = other.underline;
526 }
527
528 match (other.fade_out, self.fade_out) {
529 (Some(source_fade), None) => self.fade_out = Some(source_fade),
530 (Some(source_fade), Some(dest_fade)) => {
531 self.fade_out = Some((dest_fade * (1. + source_fade)).clamp(0., 1.));
532 }
533 _ => {}
534 }
535 }
536}
537
538impl From<Hsla> for HighlightStyle {
539 fn from(color: Hsla) -> Self {
540 Self {
541 color: Some(color),
542 ..Default::default()
543 }
544 }
545}
546
547impl From<FontWeight> for HighlightStyle {
548 fn from(font_weight: FontWeight) -> Self {
549 Self {
550 font_weight: Some(font_weight),
551 ..Default::default()
552 }
553 }
554}
555
556impl From<FontStyle> for HighlightStyle {
557 fn from(font_style: FontStyle) -> Self {
558 Self {
559 font_style: Some(font_style),
560 ..Default::default()
561 }
562 }
563}
564
565impl From<Rgba> for HighlightStyle {
566 fn from(color: Rgba) -> Self {
567 Self {
568 color: Some(color.into()),
569 ..Default::default()
570 }
571 }
572}
573
574pub fn combine_highlights(
575 a: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
576 b: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
577) -> impl Iterator<Item = (Range<usize>, HighlightStyle)> {
578 let mut endpoints = Vec::new();
579 let mut highlights = Vec::new();
580 for (range, highlight) in a.into_iter().chain(b) {
581 if !range.is_empty() {
582 let highlight_id = highlights.len();
583 endpoints.push((range.start, highlight_id, true));
584 endpoints.push((range.end, highlight_id, false));
585 highlights.push(highlight);
586 }
587 }
588 endpoints.sort_unstable_by_key(|(position, _, _)| *position);
589 let mut endpoints = endpoints.into_iter().peekable();
590
591 let mut active_styles = HashSet::default();
592 let mut ix = 0;
593 iter::from_fn(move || {
594 while let Some((endpoint_ix, highlight_id, is_start)) = endpoints.peek() {
595 let prev_index = mem::replace(&mut ix, *endpoint_ix);
596 if ix > prev_index && !active_styles.is_empty() {
597 let mut current_style = HighlightStyle::default();
598 for highlight_id in &active_styles {
599 current_style.highlight(highlights[*highlight_id]);
600 }
601 return Some((prev_index..ix, current_style));
602 }
603
604 if *is_start {
605 active_styles.insert(*highlight_id);
606 } else {
607 active_styles.remove(highlight_id);
608 }
609 endpoints.next();
610 }
611 None
612 })
613}
614
615#[cfg(test)]
616mod tests {
617 use crate::{blue, green, red, yellow};
618
619 use super::*;
620
621 #[test]
622 fn test_combine_highlights() {
623 assert_eq!(
624 combine_highlights(
625 [
626 (0..5, green().into()),
627 (4..10, FontWeight::BOLD.into()),
628 (15..20, yellow().into()),
629 ],
630 [
631 (2..6, FontStyle::Italic.into()),
632 (1..3, blue().into()),
633 (21..23, red().into()),
634 ]
635 )
636 .collect::<Vec<_>>(),
637 [
638 (
639 0..1,
640 HighlightStyle {
641 color: Some(green()),
642 ..Default::default()
643 }
644 ),
645 (
646 1..2,
647 HighlightStyle {
648 color: Some(green()),
649 ..Default::default()
650 }
651 ),
652 (
653 2..3,
654 HighlightStyle {
655 color: Some(green()),
656 font_style: Some(FontStyle::Italic),
657 ..Default::default()
658 }
659 ),
660 (
661 3..4,
662 HighlightStyle {
663 color: Some(green()),
664 font_style: Some(FontStyle::Italic),
665 ..Default::default()
666 }
667 ),
668 (
669 4..5,
670 HighlightStyle {
671 color: Some(green()),
672 font_weight: Some(FontWeight::BOLD),
673 font_style: Some(FontStyle::Italic),
674 ..Default::default()
675 }
676 ),
677 (
678 5..6,
679 HighlightStyle {
680 font_weight: Some(FontWeight::BOLD),
681 font_style: Some(FontStyle::Italic),
682 ..Default::default()
683 }
684 ),
685 (
686 6..10,
687 HighlightStyle {
688 font_weight: Some(FontWeight::BOLD),
689 ..Default::default()
690 }
691 ),
692 (
693 15..20,
694 HighlightStyle {
695 color: Some(yellow()),
696 ..Default::default()
697 }
698 ),
699 (
700 21..23,
701 HighlightStyle {
702 color: Some(red()),
703 ..Default::default()
704 }
705 )
706 ]
707 );
708 }
709}