feat: allow .subplot to list CSS files to embed in HTML output

This is in the meta data field "css_embed".

Signed-off-by: Lars Wirzenius <liw@liw.fi>
Sponsored-by: author

2 files changed, 22 insertions, 0 deletions

diff --git a/src/doc.rs b/src/doc.rs
index f3f9641..83b5ec2 100644
--- a/src/doc.rs
+++ b/src/doc.rs
@@ -155,6 +155,9 @@ impl Document {
 
         let mut css = Element::new(ElementTag::Style);
         css.push_child(Content::Text(CSS.into()));
+        for css_file in self.meta.css_embed() {
+            css.push_child(Content::Text(css_file.into()));
+        }
         head.push_child(Content::Elt(css));
 
         self.meta.set_date(date.into());
diff --git a/src/metadata.rs b/src/metadata.rs
index e3463b3..dc28ac4 100644
--- a/src/metadata.rs
+++ b/src/metadata.rs
@@ -50,6 +50,7 @@ pub struct YamlMetadata {
     documentclass: Option<String>,
     #[serde(default)]
     impls: BTreeMap<String, Vec<PathBuf>>,
+    css_embed: Option<Vec<PathBuf>>,
 }
 
 impl YamlMetadata {
@@ -167,6 +168,7 @@ pub struct Metadata {
     impls: HashMap<String, DocumentImpl>,
     /// Extra class names which should be considered 'correct' for this document
     classes: Vec<String>,
+    css_embed: Vec<String>,
 }
 
 #[derive(Debug)]
@@ -208,6 +210,17 @@ impl Metadata {
             vec![]
         };
 
+        let mut css_embed = vec![];
+        if let Some(filenames) = &yaml.css_embed {
+            for filename in filenames.iter() {
+                let css = std::fs::read(filename)
+                    .map_err(|e| SubplotError::ReadFile(filename.into(), e))?;
+                let css = String::from_utf8(css)
+                    .map_err(|e| SubplotError::FileUtf8(filename.into(), e))?;
+                css_embed.push(css);
+            }
+        }
+
         let meta = Self {
             basedir: basedir.as_ref().to_path_buf(),
             title: yaml.title().into(),
@@ -218,6 +231,7 @@ impl Metadata {
             bindings,
             impls,
             classes,
+            css_embed,
         };
         trace!("metadata: {:#?}", meta);
 
@@ -278,6 +292,11 @@ impl Metadata {
     pub fn classes(&self) -> impl Iterator<Item = &str> {
         self.classes.iter().map(Deref::deref)
     }
+
+    /// Contents of CSS files to embed into the HTML output.
+    pub fn css_embed(&self) -> impl Iterator<Item = &str> {
+        self.css_embed.iter().map(Deref::deref)
+    }
 }
 
 impl DocumentImpl {