WIP [no ci]

crates/typst-library/src/foundations/content.rs

@@ -16,12 +16,12 @@ use crate::diag::{SourceResult, StrResult};
 use crate::engine::Engine;
 use crate::foundations::{
     elem, func, scope, ty, Context, Dict, Element, Fields, IntoValue, Label,
-    NativeElement, Recipe, RecipeIndex, Repr, Selector, Str, Style, StyleChain, Styles,
+    NativeElement, Recipe, RecipeIndex, Repr, Selector, Show, Str, Style, StyleChain,
-    Value,
+    Styles, Value,
 };
-use crate::introspection::Location;
+use crate::introspection::{Locatable, Location};
 use crate::layout::{AlignElem, Alignment, Axes, Length, MoveElem, PadElem, Rel, Sides};
-use crate::model::{Destination, EmphElem, LinkElem, StrongElem};
+use crate::model::{Destination, EmphElem, StrongElem};
 use crate::pdf::{ArtifactElem, ArtifactKind};
 use crate::text::UnderlineElem;
 
@@ -504,9 +504,9 @@ impl Content {
     }
 
     /// Link the content somewhere.
-    pub fn linked(self, alt: Option<EcoString>, dest: Destination) -> Self {
+    pub fn linked(self, dest: Destination, alt: Option<EcoString>) -> Self {
-        self.styled(LinkElem::set_alt(alt))
+        let span = self.span();
-            .styled(LinkElem::set_current(Some(dest)))
+        LinkMarker::new(self, dest, alt).pack().spanned(span)
     }
 
     /// Set alignments for this content.
@@ -988,6 +988,26 @@ pub trait PlainText {
     fn plain_text(&self, text: &mut EcoString);
 }
 
+
+// TODO: remove `FrameItem::Link` and `FrameModifiers::dest`, then handle links by looking at tags
+/// An element that associates the body of a link with the destination.
+#[elem(Show, Locatable)]
+pub struct LinkMarker {
+    /// The content.
+    #[required]
+    pub body: Content,
+    #[required]
+    pub dest: Destination,
+    #[required]
+    pub alt: Option<EcoString>,
+}
+
+impl Show for Packed<LinkMarker> {
+    fn show(&self, _: &mut Engine, _: StyleChain) -> SourceResult<Content> {
+        Ok(self.body.clone())
+    }
+}
+
 /// An error arising when trying to access a field of content.
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
 pub enum FieldAccessError {

crates/typst-library/src/foundations/styles.rs

@@ -523,6 +523,8 @@ pub struct StyleChain<'a> {
 }
 
 impl<'a> StyleChain<'a> {
+    pub const EMPTY: Self = Self { head: &[], tail: None };
+
     /// Start a new style chain with root styles.
     pub fn new(root: &'a Styles) -> Self {
         Self { head: &root.0, tail: None }

crates/typst-library/src/model/bibliography.rs

@@ -874,7 +874,7 @@ impl<'a> Generator<'a> {
                     if let Some(location) = first_occurrences.get(item.key.as_str()) {
                         let dest = Destination::Location(*location);
                         // TODO: accept user supplied alt text
-                        content = content.linked(None, dest);
+                        content = content.linked(dest, None);
                     }
                     StrResult::Ok(content)
                 })
@@ -1010,7 +1010,7 @@ impl ElemRenderer<'_> {
             if let Some(location) = (self.link)(i) {
                 let dest = Destination::Location(location);
                 // TODO: accept user supplied alt text
-                content = content.linked(None, dest);
+                content = content.linked(dest, None);
             }
         }
 

crates/typst-library/src/model/footnote.rs

@@ -148,7 +148,7 @@ impl Show for Packed<FootnoteElem> {
         let loc = loc.variant(1);
         // Add zero-width weak spacing to make the footnote "sticky".
         // TODO: accept user supplied alt text
-        Ok(HElem::hole().pack() + sup.linked(None, Destination::Location(loc)))
+        Ok(HElem::hole().pack() + sup.linked(Destination::Location(loc), None))
     }
 }
 
@@ -298,7 +298,7 @@ impl Show for Packed<FootnoteEntry> {
             .pack()
             .spanned(span)
             // TODO: accept user supplied alt text
-            .linked(None, Destination::Location(loc))
+            .linked(Destination::Location(loc), None)
             .located(loc.variant(1));
 
         Ok(Content::sequence([

crates/typst-library/src/model/link.rs

@@ -91,11 +91,6 @@ pub struct LinkElem {
         _ => args.expect("body")?,
     })]
     pub body: Content,
-
-    /// A destination style that should be applied to elements.
-    #[internal]
-    #[ghost]
-    pub current: Option<Destination>,
 }
 
 impl LinkElem {
@@ -128,11 +123,11 @@ impl Show for Packed<LinkElem> {
         } else {
             let alt = self.alt(styles);
             match &self.dest {
-                LinkTarget::Dest(dest) => body.linked(alt, dest.clone()),
+                LinkTarget::Dest(dest) => body.linked(dest.clone(), alt),
                 LinkTarget::Label(label) => {
                     let elem = engine.introspector.query_label(*label).at(self.span())?;
                     let dest = Destination::Location(elem.location().unwrap());
-                    body.clone().linked(alt, dest)
+                    body.clone().linked(dest, alt)
                 }
             }
         })

crates/typst-library/src/model/outline.rs

@@ -446,7 +446,7 @@ impl Show for Packed<OutlineEntry> {
         };
 
         let loc = self.element_location().at(span)?;
-        Ok(block.linked(Some(alt), Destination::Location(loc)))
+        Ok(block.linked(Destination::Location(loc), Some(alt)))
     }
 }
 

crates/typst-library/src/model/reference.rs

@@ -310,7 +310,7 @@ fn show_reference(
     }
 
     // TODO: accept user supplied alt text
-    Ok(content.linked(None, Destination::Location(loc)))
+    Ok(content.linked(Destination::Location(loc), None))
 }
 
 /// Turn a reference into a citation.

crates/typst-pdf/src/image.rs

@@ -30,10 +30,6 @@ pub(crate) fn handle_image(
 
     let interpolate = image.scaling() == Smart::Custom(ImageScaling::Smooth);
 
-    if let Some(alt) = image.alt() {
-        surface.start_alt_text(alt);
-    }
-
     gc.image_spans.insert(span);
 
     match image.kind() {
@@ -62,10 +58,6 @@ pub(crate) fn handle_image(
         }
     }
 
-    if image.alt().is_some() {
-        surface.end_alt_text();
-    }
-
     surface.pop();
     surface.reset_location();
 

crates/typst-pdf/src/tags.rs

@@ -9,10 +9,11 @@ use krilla::tagging::{
 use typst_library::foundations::{Content, StyleChain};
 use typst_library::introspection::Location;
 use typst_library::model::{
-    CiteElem, FigureCaption, FigureElem, HeadingElem, LinkElem, OutlineElem,
+    CiteElem, FigureCaption, FigureElem, HeadingElem, LinkElem, Outlinable, OutlineElem,
     OutlineEntry, RefElem,
 };
 use typst_library::pdf::{ArtifactElem, ArtifactKind, PdfTagElem, PdfTagKind};
+use typst_library::visualize::ImageElem;
 
 use crate::convert::GlobalContext;
 
@@ -177,7 +178,7 @@ pub(crate) fn handle_start(
             _ => todo!(),
         }
     } else if let Some(heading) = elem.to_packed::<HeadingElem>() {
-        let level = heading.resolve_level(StyleChain::default());
+        let level = heading.level();
         let name = heading.body.plain_text().to_string();
         match level.get() {
             1 => Tag::H1(Some(name)),
@@ -195,6 +196,25 @@ pub(crate) fn handle_start(
     } else if let Some(_) = elem.to_packed::<FigureElem>() {
         let alt = None; // TODO
         Tag::Figure(alt)
+    } else if let Some(image) = elem.to_packed::<ImageElem>() {
+        let alt = image.alt(StyleChain::default()).map(|s| s.to_string());
+
+        end_open(gc, surface);
+        let id = surface.start_tagged(ContentTag::Other);
+        let mut node = TagNode::Leaf(id);
+
+        if let Some(Tag::Figure(alt_text)) = gc.tags.parent().0 {
+            // HACK: set alt text of outer figure tag, if the contained image
+            // has alt text specified
+            if alt_text.is_none() {
+                *alt_text = alt;
+            }
+        } else {
+            node = TagNode::Group(Tag::Figure(alt), vec![node]);
+        }
+        gc.tags.push(node);
+
+        return;
     } else if let Some(_) = elem.to_packed::<FigureCaption>() {
         Tag::Caption
     } else if let Some(_) = elem.to_packed::<LinkElem>() {
@@ -212,9 +232,7 @@ pub(crate) fn handle_start(
     }
 
     // close previous marked-content and open a nested tag.
-    if !gc.tags.stack.is_empty() {
+    end_open(gc, surface);
-        surface.end_tagged();
-    }
     let id = surface.start_tagged(krilla::tagging::ContentTag::Other);
     gc.tags.stack.push((loc, tag, vec![TagNode::Leaf(id)]));
 }