Handle Invalid Markdown (#218)

markdown: use builtin dark/light theme detection

handle invalid markdown

Co-authored-by: Norwin Roosen <git@nroo.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/218
Reviewed-by: 6543 <6543@noreply.gitea.io>
Reviewed-by: techknowlogick <techknowlogick@gitea.io>

modules/print/markdown.go

@@ -0,0 +1,24 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package print
+
+import (
+	"fmt"
+
+	"github.com/charmbracelet/glamour"
+)
+
+// OutputMarkdown prints markdown to stdout, formatted for terminals.
+// If the input could not be parsed, it is printed unformatted, the error
+// is returned anyway.
+func OutputMarkdown(markdown string) error {
+	out, err := glamour.Render(markdown, "auto")
+	if err != nil {
+		fmt.Printf(markdown)
+		return err
+	}
+	fmt.Print(out)
+	return nil
+}