init

handler/utils.go

@@ -0,0 +1,58 @@
+package handler
+
+import (
+	"crypto/rand"
+	"strings"
+
+	"github.com/alecthomas/chroma/v2/formatters/html"
+	"github.com/alecthomas/chroma/v2/lexers"
+	"github.com/alecthomas/chroma/v2/styles"
+)
+
+const charset = "abcdefghijklmnopqrstuvwxyz0123456789"
+
+func generateId() (string, error) {
+	bytes := make([]byte, 10)
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+
+	for i := range bytes {
+		bytes[i] = charset[bytes[i]%byte(len(charset))]
+	}
+	return string(bytes), nil
+}
+
+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
+		}
+	}
+
+	formatter := html.New(
+		html.WithLineNumbers(false),
+		html.Standalone(false),
+		html.TabWidth(4),
+		html.WithLineNumbers(true),
+	)
+
+	style := styles.Get(theme)
+	if style == nil {
+		style = styles.Fallback
+	}
+
+	iterator, err := lexer.Tokenise(nil, content)
+	if err != nil {
+		return "", err
+	}
+
+	var buf strings.Builder
+	err = formatter.Format(&buf, style, iterator)
+	if err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}