use crate::{    black, fill, point, px, size, Bounds, Half, Hsla, LineLayout, Pixels, Point, Result,    SharedString, StrikethroughStyle, UnderlineStyle, WindowContext, WrapBoundary,    WrappedLineLayout,};use derive_more::{Deref, DerefMut};use smallvec::SmallVec;use std::sync::Arc; /// Set the text decoration for a run of text.#[derive(Debug, Clone)]pub struct DecorationRun {    /// The length of the run in utf-8 bytes.    pub len: u32,     /// The color for this run    pub color: Hsla,     /// The background color for this run    pub background_color: Option<Hsla>,     /// The underline style for this run    pub underline: Option<UnderlineStyle>,     /// The strikethrough style for this run    pub strikethrough: Option<StrikethroughStyle>,} /// A line of text that has been shaped and decorated.#[derive(Clone, Default, Debug, Deref, DerefMut)]pub struct ShapedLine {    #[deref]    #[deref_mut]    pub(crate) layout: Arc<LineLayout>,    /// The text that was shaped for this line.    pub text: SharedString,    pub(crate) decoration_runs: SmallVec<[DecorationRun; 32]>,} impl ShapedLine {    /// The length of the line in utf-8 bytes.    #[allow(clippy::len_without_is_empty)]    pub fn len(&self) -> usize {        self.layout.len    }     /// Override the len, useful if you're rendering text a    /// as text b (e.g. rendering invisibles).    pub fn with_len(mut self, len: usize) -> Self {        let layout = self.layout.as_ref();        self.layout = Arc::new(LineLayout {            font_size: layout.font_size,            width: layout.width,            ascent: layout.ascent,            descent: layout.descent,            runs: layout.runs.clone(),            len,        });        self    }     /// Paint the line of text to the window.    pub fn paint(        &self,        origin: Point<Pixels>,        line_height: Pixels,        cx: &mut WindowContext,    ) -> Result<()> {        paint_line(            origin,            &self.layout,            line_height,            &self.decoration_runs,            &[],            cx,        )?;         Ok(())    }} /// A line of text that has been shaped, decorated, and wrapped by the text layout system.#[derive(Clone, Default, Debug, Deref, DerefMut)]pub struct WrappedLine {    #[deref]    #[deref_mut]    pub(crate) layout: Arc<WrappedLineLayout>,    /// The text that was shaped for this line.    pub text: SharedString,    pub(crate) decoration_runs: SmallVec<[DecorationRun; 32]>,} impl WrappedLine {    /// The length of the underlying, unwrapped layout, in utf-8 bytes.    #[allow(clippy::len_without_is_empty)]    pub fn len(&self) -> usize {        self.layout.len()    }     /// Paint this line of text to the window.    pub fn paint(        &self,        origin: Point<Pixels>,        line_height: Pixels,        cx: &mut WindowContext,    ) -> Result<()> {        paint_line(            origin,            &self.layout.unwrapped_layout,            line_height,            &self.decoration_runs,            &self.wrap_boundaries,            cx,        )?;         Ok(())    }} fn paint_line(    origin: Point<Pixels>,    layout: &LineLayout,    line_height: Pixels,    decoration_runs: &[DecorationRun],    wrap_boundaries: &[WrapBoundary],    cx: &mut WindowContext,) -> Result<()> {    let line_bounds = Bounds::new(        origin,        size(            layout.width,            line_height * (wrap_boundaries.len() as f32 + 1.),        ),    );    cx.paint_layer(line_bounds, |cx| {        let padding_top = (line_height - layout.ascent - layout.descent) / 2.;        let baseline_offset = point(px(0.), padding_top + layout.ascent);        let mut decoration_runs = decoration_runs.iter();        let mut wraps = wrap_boundaries.iter().peekable();        let mut run_end = 0;        let mut color = black();        let mut current_underline: Option<(Point<Pixels>, UnderlineStyle)> = None;        let mut current_strikethrough: Option<(Point<Pixels>, StrikethroughStyle)> = None;        let mut current_background: Option<(Point<Pixels>, Hsla)> = None;        let text_system = cx.text_system().clone();        let mut glyph_origin = origin;        let mut prev_glyph_position = Point::default();        let mut max_glyph_size = size(px(0.), px(0.));        for (run_ix, run) in layout.runs.iter().enumerate() {            max_glyph_size = text_system.bounding_box(run.font_id, layout.font_size).size;             for (glyph_ix, glyph) in run.glyphs.iter().enumerate() {                glyph_origin.x += glyph.position.x - prev_glyph_position.x;                 if wraps.peek() == Some(&&WrapBoundary { run_ix, glyph_ix }) {                    wraps.next();                    if let Some((background_origin, background_color)) = current_background.as_mut()                    {                        if glyph_origin.x == background_origin.x {                            background_origin.x -= max_glyph_size.width.half()                        }                        cx.paint_quad(fill(                            Bounds {                                origin: *background_origin,                                size: size(glyph_origin.x - background_origin.x, line_height),                            },                            *background_color,                        ));                        background_origin.x = origin.x;                        background_origin.y += line_height;                    }                    if let Some((underline_origin, underline_style)) = current_underline.as_mut() {                        if glyph_origin.x == underline_origin.x {                            underline_origin.x -= max_glyph_size.width.half();                        };                        cx.paint_underline(                            *underline_origin,                            glyph_origin.x - underline_origin.x,                            underline_style,                        );                        underline_origin.x = origin.x;                        underline_origin.y += line_height;                    }                    if let Some((strikethrough_origin, strikethrough_style)) =                        current_strikethrough.as_mut()                    {                        if glyph_origin.x == strikethrough_origin.x {                            strikethrough_origin.x -= max_glyph_size.width.half();                        };                        cx.paint_strikethrough(                            *strikethrough_origin,                            glyph_origin.x - strikethrough_origin.x,                            strikethrough_style,                        );                        strikethrough_origin.x = origin.x;                        strikethrough_origin.y += line_height;                    }                     glyph_origin.x = origin.x;                    glyph_origin.y += line_height;                }                prev_glyph_position = glyph.position;                 let mut finished_background: Option<(Point<Pixels>, Hsla)> = None;                let mut finished_underline: Option<(Point<Pixels>, UnderlineStyle)> = None;                let mut finished_strikethrough: Option<(Point<Pixels>, StrikethroughStyle)> = None;                if glyph.index >= run_end {                    let mut style_run = decoration_runs.next();                     // ignore style runs that apply to a partial glyph                    while let Some(run) = style_run {                        if glyph.index < run_end + (run.len as usize) {                            break;                        }                        run_end += run.len as usize;                        style_run = decoration_runs.next();                    }                     if let Some(style_run) = style_run {                        if let Some((_, background_color)) = &mut current_background {                            if style_run.background_color.as_ref() != Some(background_color) {                                finished_background = current_background.take();                            }                        }                        if let Some(run_background) = style_run.background_color {                            current_background.get_or_insert((                                point(glyph_origin.x, glyph_origin.y),                                run_background,                            ));                        }                         if let Some((_, underline_style)) = &mut current_underline {                            if style_run.underline.as_ref() != Some(underline_style) {                                finished_underline = current_underline.take();                            }                        }                        if let Some(run_underline) = style_run.underline.as_ref() {                            current_underline.get_or_insert((                                point(                                    glyph_origin.x,                                    glyph_origin.y + baseline_offset.y + (layout.descent * 0.618),                                ),                                UnderlineStyle {                                    color: Some(run_underline.color.unwrap_or(style_run.color)),                                    thickness: run_underline.thickness,                                    wavy: run_underline.wavy,                                },                            ));                        }                        if let Some((_, strikethrough_style)) = &mut current_strikethrough {                            if style_run.strikethrough.as_ref() != Some(strikethrough_style) {                                finished_strikethrough = current_strikethrough.take();                            }                        }                        if let Some(run_strikethrough) = style_run.strikethrough.as_ref() {                            current_strikethrough.get_or_insert((                                point(                                    glyph_origin.x,                                    glyph_origin.y                                        + (((layout.ascent * 0.5) + baseline_offset.y) * 0.5),                                ),                                StrikethroughStyle {                                    color: Some(run_strikethrough.color.unwrap_or(style_run.color)),                                    thickness: run_strikethrough.thickness,                                },                            ));                        }                         run_end += style_run.len as usize;                        color = style_run.color;                    } else {                        run_end = layout.len;                        finished_background = current_background.take();                        finished_underline = current_underline.take();                        finished_strikethrough = current_strikethrough.take();                    }                }                 if let Some((mut background_origin, background_color)) = finished_background {                    let mut width = glyph_origin.x - background_origin.x;                    if background_origin.x == glyph_origin.x {                        background_origin.x -= max_glyph_size.width.half();                    };                    cx.paint_quad(fill(                        Bounds {                            origin: background_origin,                            size: size(width, line_height),                        },                        background_color,                    ));                }                 if let Some((mut underline_origin, underline_style)) = finished_underline {                    if underline_origin.x == glyph_origin.x {                        underline_origin.x -= max_glyph_size.width.half();                    };                    cx.paint_underline(                        underline_origin,                        glyph_origin.x - underline_origin.x,                        &underline_style,                    );                }                 if let Some((mut strikethrough_origin, strikethrough_style)) =                    finished_strikethrough                {                    if strikethrough_origin.x == glyph_origin.x {                        strikethrough_origin.x -= max_glyph_size.width.half();                    };                    cx.paint_strikethrough(                        strikethrough_origin,                        glyph_origin.x - strikethrough_origin.x,                        &strikethrough_style,                    );                }                 let max_glyph_bounds = Bounds {                    origin: glyph_origin,                    size: max_glyph_size,                };                 let content_mask = cx.content_mask();                if max_glyph_bounds.intersects(&content_mask.bounds) {                    if glyph.is_emoji {                        cx.paint_emoji(                            glyph_origin + baseline_offset,                            run.font_id,                            glyph.id,                            layout.font_size,                        )?;                    } else {                        cx.paint_glyph(                            glyph_origin + baseline_offset,                            run.font_id,                            glyph.id,                            layout.font_size,                            color,                        )?;                    }                }            }        }         let mut last_line_end_x = origin.x + layout.width;        if let Some(boundary) = wrap_boundaries.last() {            let run = &layout.runs[boundary.run_ix];            let glyph = &run.glyphs[boundary.glyph_ix];            last_line_end_x -= glyph.position.x;        }         if let Some((mut background_origin, background_color)) = current_background.take() {            if last_line_end_x == background_origin.x {                background_origin.x -= max_glyph_size.width.half()            };            cx.paint_quad(fill(                Bounds {                    origin: background_origin,                    size: size(last_line_end_x - background_origin.x, line_height),                },                background_color,            ));        }         if let Some((mut underline_start, underline_style)) = current_underline.take() {            if last_line_end_x == underline_start.x {                underline_start.x -= max_glyph_size.width.half()            };            cx.paint_underline(                underline_start,                last_line_end_x - underline_start.x,                &underline_style,            );        }         if let Some((mut strikethrough_start, strikethrough_style)) = current_strikethrough.take() {            if last_line_end_x == strikethrough_start.x {                strikethrough_start.x -= max_glyph_size.width.half()            };            cx.paint_strikethrough(                strikethrough_start,                last_line_end_x - strikethrough_start.x,                &strikethrough_style,            );        }         Ok(())    })}