basic syntax highlighting

3 files changed, 41 insertions, 0 deletions

diff --git a/code/src/syntax_highlight/grammar.rs b/code/src/syntax_highlight/grammar.rs
new file mode 100644
index 0000000..95417ab
--- /dev/null
+++ b/code/src/syntax_highlight/grammar.rs
@@ -0,0 +1,6 @@
+pub fn grammar_for(syntax: &str) -> &'static [(&'static [&'static str], &'static str)] {
+    match syntax {
+        "rs" => &[(&["fn", "pub", "async"], "keyword")],
+        _ => unreachable!(),
+    }
+}
diff --git a/code/src/syntax_highlight/mod.rs b/code/src/syntax_highlight/mod.rs
new file mode 100644
index 0000000..688b010
--- /dev/null
+++ b/code/src/syntax_highlight/mod.rs
@@ -0,0 +1,29 @@
+pub mod grammar;
+pub mod theme;
+
+use crate::{markdown::escape, syntax_highlight::theme::theme};
+use grammar::grammar_for;
+use synoptic::{Highlighter, Token};
+
+pub fn syntax_highlight(lang: &str, source: &str) -> String {
+    let mut h = Highlighter::new();
+    for (regex, kind) in grammar_for(lang) {
+        h.join(regex, kind).unwrap();
+    }
+    let highlighting = h.run(source);
+    let mut out = String::new();
+
+    for (_c, row) in highlighting.iter().enumerate() {
+        eprintln!("{row:?}");
+        for tok in row {
+            match tok {
+                Token::Start(kind) => out += &format!("<span style=\"color:{}\">", theme(kind)),
+                Token::Text(text) => out += &escape(text),
+                Token::End(_kind) => out += "</span>",
+            }
+        }
+        out += "\n"
+    }
+    eprintln!("{out:?}");
+    out
+}
diff --git a/code/src/syntax_highlight/theme.rs b/code/src/syntax_highlight/theme.rs
new file mode 100644
index 0000000..40434ad
--- /dev/null
+++ b/code/src/syntax_highlight/theme.rs
@@ -0,0 +1,6 @@
+pub fn theme(kind: &str) -> &'static str {
+    match kind {
+        "keyword" => "#9999ff",
+        _ => "#ff00ff",
+    }
+}