v2

handler/util.go

@@ -2,10 +2,12 @@ package handler
 
 import (
 	"crypto/rand"
+	"io"
 	"net/http"
 	"strings"
 
 	"github.com/a-h/templ"
+	"github.com/alecthomas/chroma/v2"
 	"github.com/alecthomas/chroma/v2/formatters/html"
 	"github.com/alecthomas/chroma/v2/lexers"
 	"github.com/alecthomas/chroma/v2/styles"
@@ -13,9 +15,10 @@ import (
 
 const charset = "abcdefghijklmnopqrstuvwxyz0123456789"
 
+// generateId generates a random 10-character alphanumeric string.
 func generateId() (string, error) {
 	bytes := make([]byte, 10)
-	if _, err := rand.Read(bytes); err != nil {
+	if _, err := io.ReadFull(rand.Reader, bytes); err != nil {
 		return "", err
 	}
 
@@ -25,20 +28,28 @@ func generateId() (string, error) {
 	return string(bytes), nil
 }
 
+// highlight highlights the given content using the specified file extension and theme.
 func highlight(content, ext, theme string) (string, error) {
-	lexer := lexers.Get(ext)
-	if lexer == nil {
-		lexer = lexers.Analyse(content)
-		if lexer == nil {
-			lexer = lexers.Fallback
+	var lexer chroma.Lexer
+
+	if ext != "" {
+		lexer = lexers.Get(ext)
+		if lexer != nil && lexer.Config().Name == "plaintext" {
+			analysedLexer := lexers.Analyse(content)
+			if analysedLexer != nil {
+				lexer = analysedLexer
+			}
 		}
 	}
 
+	if lexer == nil {
+		lexer = lexers.Fallback
+	}
+	lexer = chroma.Coalesce(lexer)
+
 	formatter := html.New(
-		html.WithLineNumbers(false),
-		html.Standalone(false),
-		html.TabWidth(4),
 		html.WithLineNumbers(true),
+		html.TabWidth(4),
 	)
 
 	style := styles.Get(theme)
@@ -52,16 +63,15 @@ func highlight(content, ext, theme string) (string, error) {
 	}
 
 	var buf strings.Builder
-	err = formatter.Format(&buf, style, iterator)
-	if err != nil {
+	if err := formatter.Format(&buf, style, iterator); err != nil {
 		return "", err
 	}
 	return buf.String(), nil
 }
 
+// render renders the given component to the response writer, handling any errors.
 func render(component templ.Component, w http.ResponseWriter, r *http.Request) {
-	err := component.Render(r.Context(), w)
-	if err != nil {
+	if err := component.Render(r.Context(), w); err != nil {
 		internal("could not render template", err, w, r)
 	}
 }