Split crates

1 files changed, 100 insertions, 0 deletions

diff --git a/library/src/layout/spacing.rs b/library/src/layout/spacing.rs
new file mode 100644
index 00000000..67fff5db
--- /dev/null
+++ b/library/src/layout/spacing.rs
@@ -0,0 +1,100 @@
+use std::cmp::Ordering;
+
+use crate::prelude::*;
+use crate::text::ParNode;
+
+/// Horizontal spacing.
+#[derive(Debug, Clone, Hash)]
+pub struct HNode {
+    pub amount: Spacing,
+    pub weak: bool,
+}
+
+#[node]
+impl HNode {
+    fn construct(_: &mut Vm, args: &mut Args) -> SourceResult<Content> {
+        let amount = args.expect("spacing")?;
+        let weak = args.named("weak")?.unwrap_or(false);
+        Ok(Self { amount, weak }.pack())
+    }
+}
+
+/// Vertical spacing.
+#[derive(Debug, Clone, Hash)]
+pub struct VNode {
+    pub amount: Spacing,
+    pub weak: bool,
+    pub generated: bool,
+}
+
+#[node]
+impl VNode {
+    fn construct(_: &mut Vm, args: &mut Args) -> SourceResult<Content> {
+        let amount = args.expect("spacing")?;
+        let weak = args.named("weak")?.unwrap_or(false);
+        Ok(Self { amount, weak, generated: false }.pack())
+    }
+}
+
+/// Kinds of spacing.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
+pub enum Spacing {
+    /// Spacing specified in absolute terms and relative to the parent's size.
+    Relative(Rel<Length>),
+    /// Spacing specified as a fraction of the remaining free space in the
+    /// parent.
+    Fractional(Fr),
+}
+
+impl Spacing {
+    /// Whether this is fractional spacing.
+    pub fn is_fractional(self) -> bool {
+        matches!(self, Self::Fractional(_))
+    }
+}
+
+impl From<Abs> for Spacing {
+    fn from(abs: Abs) -> Self {
+        Self::Relative(abs.into())
+    }
+}
+
+impl PartialOrd for Spacing {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        match (self, other) {
+            (Self::Relative(a), Self::Relative(b)) => a.partial_cmp(b),
+            (Self::Fractional(a), Self::Fractional(b)) => a.partial_cmp(b),
+            _ => None,
+        }
+    }
+}
+
+castable! {
+    Spacing,
+    Expected: "relative length or fraction",
+    Value::Length(v) => Self::Relative(v.into()),
+    Value::Ratio(v) => Self::Relative(v.into()),
+    Value::Relative(v) => Self::Relative(v),
+    Value::Fraction(v) => Self::Fractional(v),
+}
+
+/// Spacing around and between blocks, relative to paragraph spacing.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
+pub struct BlockSpacing(Rel<Length>);
+
+castable!(BlockSpacing: Rel<Length>);
+
+impl Resolve for BlockSpacing {
+    type Output = Abs;
+
+    fn resolve(self, styles: StyleChain) -> Self::Output {
+        let whole = styles.get(ParNode::SPACING);
+        self.0.resolve(styles).relative_to(whole)
+    }
+}
+
+impl From<Ratio> for BlockSpacing {
+    fn from(ratio: Ratio) -> Self {
+        Self(ratio.into())
+    }
+}