Move `html` module to `typst-html` crate (#6577)

9 files changed, 184 insertions, 176 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 550c4141..5526da48 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2971,8 +2971,12 @@ dependencies = [
 name = "typst-html"
 version = "0.13.1"
 dependencies = [
+ "bumpalo",
  "comemo",
  "ecow",
+ "palette",
+ "time",
+ "typst-assets",
  "typst-library",
  "typst-macros",
  "typst-svg",
diff --git a/crates/typst-html/Cargo.toml b/crates/typst-html/Cargo.toml
index 534848f9..54cad012 100644
--- a/crates/typst-html/Cargo.toml
+++ b/crates/typst-html/Cargo.toml
@@ -13,14 +13,18 @@ keywords = { workspace = true }
 readme = { workspace = true }
 
 [dependencies]
+typst-assets = { workspace = true }
 typst-library = { workspace = true }
 typst-macros = { workspace = true }
 typst-syntax = { workspace = true }
 typst-timing = { workspace = true }
 typst-utils = { workspace = true }
 typst-svg = { workspace = true }
+bumpalo = { workspace = true }
 comemo = { workspace = true }
 ecow = { workspace = true }
+palette = { workspace = true }
+time = { workspace = true }
 
 [lints]
 workspace = true
diff --git a/crates/typst-html/src/css.rs b/crates/typst-html/src/css.rs
new file mode 100644
index 00000000..2b659188
--- /dev/null
+++ b/crates/typst-html/src/css.rs
@@ -0,0 +1,135 @@
+//! Conversion from Typst data types into CSS data types.
+
+use std::fmt::{self, Display};
+
+use typst_library::layout::Length;
+use typst_library::visualize::{Color, Hsl, LinearRgb, Oklab, Oklch, Rgb};
+use typst_utils::Numeric;
+
+pub fn length(length: Length) -> impl Display {
+    typst_utils::display(move |f| match (length.abs.is_zero(), length.em.is_zero()) {
+        (false, false) => {
+            write!(f, "calc({}pt + {}em)", length.abs.to_pt(), length.em.get())
+        }
+        (true, false) => write!(f, "{}em", length.em.get()),
+        (_, true) => write!(f, "{}pt", length.abs.to_pt()),
+    })
+}
+
+pub fn color(color: Color) -> impl Display {
+    typst_utils::display(move |f| match color {
+        Color::Rgb(_) | Color::Cmyk(_) | Color::Luma(_) => rgb(f, color.to_rgb()),
+        Color::Oklab(v) => oklab(f, v),
+        Color::Oklch(v) => oklch(f, v),
+        Color::LinearRgb(v) => linear_rgb(f, v),
+        Color::Hsl(_) | Color::Hsv(_) => hsl(f, color.to_hsl()),
+    })
+}
+
+fn oklab(f: &mut fmt::Formatter<'_>, v: Oklab) -> fmt::Result {
+    write!(f, "oklab({} {} {}{})", percent(v.l), number(v.a), number(v.b), alpha(v.alpha))
+}
+
+fn oklch(f: &mut fmt::Formatter<'_>, v: Oklch) -> fmt::Result {
+    write!(
+        f,
+        "oklch({} {} {}deg{})",
+        percent(v.l),
+        number(v.chroma),
+        number(v.hue.into_degrees()),
+        alpha(v.alpha)
+    )
+}
+
+fn rgb(f: &mut fmt::Formatter<'_>, v: Rgb) -> fmt::Result {
+    if let Some(v) = rgb_to_8_bit_lossless(v) {
+        let (r, g, b, a) = v.into_components();
+        write!(f, "#{r:02x}{g:02x}{b:02x}")?;
+        if a != u8::MAX {
+            write!(f, "{a:02x}")?;
+        }
+        Ok(())
+    } else {
+        write!(
+            f,
+            "rgb({} {} {}{})",
+            percent(v.red),
+            percent(v.green),
+            percent(v.blue),
+            alpha(v.alpha)
+        )
+    }
+}
+
+/// Converts an f32 RGBA color to its 8-bit representation if the result is
+/// [very close](is_very_close) to the original.
+fn rgb_to_8_bit_lossless(
+    v: Rgb,
+) -> Option<palette::rgb::Rgba<palette::encoding::Srgb, u8>> {
+    let l = v.into_format::<u8, u8>();
+    let h = l.into_format::<f32, f32>();
+    (is_very_close(v.red, h.red)
+        && is_very_close(v.blue, h.blue)
+        && is_very_close(v.green, h.green)
+        && is_very_close(v.alpha, h.alpha))
+    .then_some(l)
+}
+
+fn linear_rgb(f: &mut fmt::Formatter<'_>, v: LinearRgb) -> fmt::Result {
+    write!(
+        f,
+        "color(srgb-linear {} {} {}{})",
+        percent(v.red),
+        percent(v.green),
+        percent(v.blue),
+        alpha(v.alpha),
+    )
+}
+
+fn hsl(f: &mut fmt::Formatter<'_>, v: Hsl) -> fmt::Result {
+    write!(
+        f,
+        "hsl({}deg {} {}{})",
+        number(v.hue.into_degrees()),
+        percent(v.saturation),
+        percent(v.lightness),
+        alpha(v.alpha),
+    )
+}
+
+/// Displays an alpha component if it not 1.
+fn alpha(value: f32) -> impl Display {
+    typst_utils::display(move |f| {
+        if !is_very_close(value, 1.0) {
+            write!(f, " / {}", percent(value))?;
+        }
+        Ok(())
+    })
+}
+
+/// Displays a rounded percentage.
+///
+/// For a percentage, two significant digits after the comma gives us a
+/// precision of 1/10_000, which is more than 12 bits (see `is_very_close`).
+fn percent(ratio: f32) -> impl Display {
+    typst_utils::display(move |f| {
+        write!(f, "{}%", typst_utils::round_with_precision(ratio as f64 * 100.0, 2))
+    })
+}
+
+/// Rounds a number for display.
+///
+/// For a number between 0 and 1, four significant digits give us a
+/// precision of 1/10_000, which is more than 12 bits (see `is_very_close`).
+fn number(value: f32) -> impl Display {
+    typst_utils::round_with_precision(value as f64, 4)
+}
+
+/// Whether two component values are close enough that there is no
+/// difference when encoding them with 12-bit. 12 bit is the highest
+/// reasonable color bit depth found in the industry.
+fn is_very_close(a: f32, b: f32) -> bool {
+    const MAX_BIT_DEPTH: u32 = 12;
+    const EPS: f32 = 0.5 / 2_i32.pow(MAX_BIT_DEPTH) as f32;
+    (a - b).abs() < EPS
+}
diff --git a/crates/typst-html/src/lib.rs b/crates/typst-html/src/lib.rs
index 19eb1446..7063931b 100644
--- a/crates/typst-html/src/lib.rs
+++ b/crates/typst-html/src/lib.rs
@@ -1,7 +1,9 @@
 //! Typst's HTML exporter.
 
+mod css;
 mod encode;
 mod rules;
+mod typed;
 
 pub use self::encode::html;
 pub use self::rules::register;
@@ -9,7 +11,9 @@ pub use self::rules::register;
 use comemo::{Track, Tracked, TrackedMut};
 use typst_library::diag::{bail, warning, At, SourceResult};
 use typst_library::engine::{Engine, Route, Sink, Traced};
-use typst_library::foundations::{Content, StyleChain, Target, TargetElem};
+use typst_library::foundations::{
+    Content, Module, Scope, StyleChain, Target, TargetElem,
+};
 use typst_library::html::{
     attr, tag, FrameElem, HtmlDocument, HtmlElem, HtmlElement, HtmlFrame, HtmlNode,
 };
@@ -20,9 +24,19 @@ use typst_library::layout::{Abs, Axes, BlockBody, BlockElem, BoxElem, Region, Si
 use typst_library::model::{DocumentInfo, ParElem};
 use typst_library::routines::{Arenas, FragmentKind, Pair, RealizationKind, Routines};
 use typst_library::text::{LinebreakElem, SmartQuoteElem, SpaceElem, TextElem};
-use typst_library::World;
+use typst_library::{Category, World};
 use typst_syntax::Span;
 
+/// Create a module with all HTML definitions.
+pub fn module() -> Module {
+    let mut html = Scope::deduplicating();
+    html.start_category(Category::Html);
+    html.define_elem::<HtmlElem>();
+    html.define_elem::<FrameElem>();
+    crate::typed::define(&mut html);
+    Module::new("html", html)
+}
+
 /// Produce an HTML document from content.
 ///
 /// This first performs root-level realization and then turns the resulting
diff --git a/crates/typst-library/src/html/typed.rs b/crates/typst-html/src/typed.rs
index 8240b296..4b794bbb 100644
--- a/crates/typst-library/src/html/typed.rs
+++ b/crates/typst-html/src/typed.rs
@@ -11,19 +11,20 @@ use bumpalo::Bump;
 use comemo::Tracked;
 use ecow::{eco_format, eco_vec, EcoString};
 use typst_assets::html as data;
-use typst_macros::cast;
-
-use crate::diag::{bail, At, Hint, HintedStrResult, SourceResult};
-use crate::engine::Engine;
-use crate::foundations::{
+use typst_library::diag::{bail, At, Hint, HintedStrResult, SourceResult};
+use typst_library::engine::Engine;
+use typst_library::foundations::{
     Args, Array, AutoValue, CastInfo, Content, Context, Datetime, Dict, Duration,
     FromValue, IntoValue, NativeFuncData, NativeFuncPtr, NoneValue, ParamInfo,
     PositiveF64, Reflect, Scope, Str, Type, Value,
 };
-use crate::html::tag;
-use crate::html::{HtmlAttr, HtmlAttrs, HtmlElem, HtmlTag};
-use crate::layout::{Axes, Axis, Dir, Length};
-use crate::visualize::Color;
+use typst_library::html::tag;
+use typst_library::html::{HtmlAttr, HtmlAttrs, HtmlElem, HtmlTag};
+use typst_library::layout::{Axes, Axis, Dir, Length};
+use typst_library::visualize::Color;
+use typst_macros::cast;
+
+use crate::css;
 
 /// Hook up all typed HTML definitions.
 pub(super) fn define(html: &mut Scope) {
@@ -705,153 +706,6 @@ impl IntoAttr for SourceSize {
     }
 }
 
-/// Conversion from Typst data types into CSS data types.
-///
-/// This can be moved elsewhere once we start supporting more CSS stuff.
-mod css {
-    use std::fmt::{self, Display};
-
-    use typst_utils::Numeric;
-
-    use crate::layout::Length;
-    use crate::visualize::{Color, Hsl, LinearRgb, Oklab, Oklch, Rgb};
-
-    pub fn length(length: Length) -> impl Display {
-        typst_utils::display(move |f| match (length.abs.is_zero(), length.em.is_zero()) {
-            (false, false) => {
-                write!(f, "calc({}pt + {}em)", length.abs.to_pt(), length.em.get())
-            }
-            (true, false) => write!(f, "{}em", length.em.get()),
-            (_, true) => write!(f, "{}pt", length.abs.to_pt()),
-        })
-    }
-
-    pub fn color(color: Color) -> impl Display {
-        typst_utils::display(move |f| match color {
-            Color::Rgb(_) | Color::Cmyk(_) | Color::Luma(_) => rgb(f, color.to_rgb()),
-            Color::Oklab(v) => oklab(f, v),
-            Color::Oklch(v) => oklch(f, v),
-            Color::LinearRgb(v) => linear_rgb(f, v),
-            Color::Hsl(_) | Color::Hsv(_) => hsl(f, color.to_hsl()),
-        })
-    }
-
-    fn oklab(f: &mut fmt::Formatter<'_>, v: Oklab) -> fmt::Result {
-        write!(
-            f,
-            "oklab({} {} {}{})",
-            percent(v.l),
-            number(v.a),
-            number(v.b),
-            alpha(v.alpha)
-        )
-    }
-
-    fn oklch(f: &mut fmt::Formatter<'_>, v: Oklch) -> fmt::Result {
-        write!(
-            f,
-            "oklch({} {} {}deg{})",
-            percent(v.l),
-            number(v.chroma),
-            number(v.hue.into_degrees()),
-            alpha(v.alpha)
-        )
-    }
-
-    fn rgb(f: &mut fmt::Formatter<'_>, v: Rgb) -> fmt::Result {
-        if let Some(v) = rgb_to_8_bit_lossless(v) {
-            let (r, g, b, a) = v.into_components();
-            write!(f, "#{r:02x}{g:02x}{b:02x}")?;
-            if a != u8::MAX {
-                write!(f, "{a:02x}")?;
-            }
-            Ok(())
-        } else {
-            write!(
-                f,
-                "rgb({} {} {}{})",
-                percent(v.red),
-                percent(v.green),
-                percent(v.blue),
-                alpha(v.alpha)
-            )
-        }
-    }
-
-    /// Converts an f32 RGBA color to its 8-bit representation if the result is
-    /// [very close](is_very_close) to the original.
-    fn rgb_to_8_bit_lossless(
-        v: Rgb,
-    ) -> Option<palette::rgb::Rgba<palette::encoding::Srgb, u8>> {
-        let l = v.into_format::<u8, u8>();
-        let h = l.into_format::<f32, f32>();
-        (is_very_close(v.red, h.red)
-            && is_very_close(v.blue, h.blue)
-            && is_very_close(v.green, h.green)
-            && is_very_close(v.alpha, h.alpha))
-        .then_some(l)
-    }
-
-    fn linear_rgb(f: &mut fmt::Formatter<'_>, v: LinearRgb) -> fmt::Result {
-        write!(
-            f,
-            "color(srgb-linear {} {} {}{})",
-            percent(v.red),
-            percent(v.green),
-            percent(v.blue),
-            alpha(v.alpha),
-        )
-    }
-
-    fn hsl(f: &mut fmt::Formatter<'_>, v: Hsl) -> fmt::Result {
-        write!(
-            f,
-            "hsl({}deg {} {}{})",
-            number(v.hue.into_degrees()),
-            percent(v.saturation),
-            percent(v.lightness),
-            alpha(v.alpha),
-        )
-    }
-
-    /// Displays an alpha component if it not 1.
-    fn alpha(value: f32) -> impl Display {
-        typst_utils::display(move |f| {
-            if !is_very_close(value, 1.0) {
-                write!(f, " / {}", percent(value))?;
-            }
-            Ok(())
-        })
-    }
-
-    /// Displays a rounded percentage.
-    ///
-    /// For a percentage, two significant digits after the comma gives us a
-    /// precision of 1/10_000, which is more than 12 bits (see `is_very_close`).
-    fn percent(ratio: f32) -> impl Display {
-        typst_utils::display(move |f| {
-            write!(f, "{}%", typst_utils::round_with_precision(ratio as f64 * 100.0, 2))
-        })
-    }
-
-    /// Rounds a number for display.
-    ///
-    /// For a number between 0 and 1, four significant digits give us a
-    /// precision of 1/10_000, which is more than 12 bits (see `is_very_close`).
-    fn number(value: f32) -> impl Display {
-        typst_utils::round_with_precision(value as f64, 4)
-    }
-
-    /// Whether two component values are close enough that there is no
-    /// difference when encoding them with 12-bit. 12 bit is the highest
-    /// reasonable color bit depth found in the industry.
-    fn is_very_close(a: f32, b: f32) -> bool {
-        const MAX_BIT_DEPTH: u32 = 12;
-        const EPS: f32 = 0.5 / 2_i32.pow(MAX_BIT_DEPTH) as f32;
-        (a - b).abs() < EPS
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/crates/typst-library/src/html/mod.rs b/crates/typst-library/src/html/mod.rs
index f9835206..ca2cc031 100644
--- a/crates/typst-library/src/html/mod.rs
+++ b/crates/typst-library/src/html/mod.rs
@@ -1,23 +1,12 @@
 //! HTML output.
 
 mod dom;
-mod typed;
 
 pub use self::dom::*;
 
 use ecow::EcoString;
 
-use crate::foundations::{elem, Content, Module, Scope};
-
-/// Create a module with all HTML definitions.
-pub fn module() -> Module {
-    let mut html = Scope::deduplicating();
-    html.start_category(crate::Category::Html);
-    html.define_elem::<HtmlElem>();
-    html.define_elem::<FrameElem>();
-    self::typed::define(&mut html);
-    Module::new("html", html)
-}
+use crate::foundations::{elem, Content};
 
 /// An HTML element that can contain Typst content.
 ///
diff --git a/crates/typst-library/src/lib.rs b/crates/typst-library/src/lib.rs
index 3e2ce99e..5d047570 100644
--- a/crates/typst-library/src/lib.rs
+++ b/crates/typst-library/src/lib.rs
@@ -165,7 +165,6 @@ pub struct Library {
 /// Constructed via the `LibraryExt` trait.
 #[derive(Debug, Clone)]
 pub struct LibraryBuilder {
-    #[expect(unused, reason = "will be used in the future")]
     routines: &'static Routines,
     inputs: Option<Dict>,
     features: Features,
@@ -200,7 +199,7 @@ impl LibraryBuilder {
     pub fn build(self) -> Library {
         let math = math::module();
         let inputs = self.inputs.unwrap_or_default();
-        let global = global(math.clone(), inputs, &self.features);
+        let global = global(self.routines, math.clone(), inputs, &self.features);
         Library {
             global: global.clone(),
             math,
@@ -282,7 +281,12 @@ impl Category {
 }
 
 /// Construct the module with global definitions.
-fn global(math: Module, inputs: Dict, features: &Features) -> Module {
+fn global(
+    routines: &Routines,
+    math: Module,
+    inputs: Dict,
+    features: &Features,
+) -> Module {
     let mut global = Scope::deduplicating();
 
     self::foundations::define(&mut global, inputs, features);
@@ -297,7 +301,7 @@ fn global(math: Module, inputs: Dict, features: &Features) -> Module {
     global.define("math", math);
     global.define("pdf", self::pdf::module());
     if features.is_enabled(Feature::Html) {
-        global.define("html", self::html::module());
+        global.define("html", (routines.html_module)());
     }
 
     prelude(&mut global);
diff --git a/crates/typst-library/src/routines.rs b/crates/typst-library/src/routines.rs
index 6db99ba5..a81806fd 100644
--- a/crates/typst-library/src/routines.rs
+++ b/crates/typst-library/src/routines.rs
@@ -8,8 +8,8 @@ use typst_utils::LazyHash;
 use crate::diag::SourceResult;
 use crate::engine::{Engine, Route, Sink, Traced};
 use crate::foundations::{
-    Args, Closure, Content, Context, Func, NativeRuleMap, Scope, StyleChain, Styles,
-    Value,
+    Args, Closure, Content, Context, Func, Module, NativeRuleMap, Scope, StyleChain,
+    Styles, Value,
 };
 use crate::introspection::{Introspector, Locator, SplitLocator};
 use crate::layout::{Frame, Region};
@@ -92,6 +92,9 @@ routines! {
         styles: StyleChain,
         region: Region,
     ) -> SourceResult<Frame>
+
+    /// Constructs the `html` module.
+    fn html_module() -> Module
 }
 
 /// Defines what kind of realization we are performing.
diff --git a/crates/typst/src/lib.rs b/crates/typst/src/lib.rs
index 11d5c9e0..591e5a9b 100644
--- a/crates/typst/src/lib.rs
+++ b/crates/typst/src/lib.rs
@@ -357,4 +357,5 @@ pub static ROUTINES: LazyLock<Routines> = LazyLock::new(|| Routines {
     eval_closure: typst_eval::eval_closure,
     realize: typst_realize::realize,
     layout_frame: typst_layout::layout_frame,
+    html_module: typst_html::module,
 });