support template overrides

1 files changed, 18 insertions, 0 deletions

diff --git a/templates.go b/templates.go
index ddce7ea..e31f06f 100644
--- a/templates.go
+++ b/templates.go
@@ -8,3 +8,21 @@ import (
 //go:embed templates/*.gmi
 var geminiTemplateFS embed.FS
 var geminiTemplate = template.Must(template.ParseFS(geminiTemplateFS, "templates/*.gmi"))
+
+func addTemplates(base *template.Template, additions *template.Template) (*template.Template, error) {
+	base, err := base.Clone()
+	if err != nil {
+		return nil, err
+	}
+	if additions == nil {
+		return base, nil
+	}
+
+	for _, addition := range additions.Templates() {
+		if _, err := base.AddParseTree(addition.Name(), addition.Tree); err != nil {
+			return nil, err
+		}
+	}
+
+	return base, nil
+}