1 files changed, 71 insertions, 8 deletions
diff --git a/internal/templatemanager/templatemanager.go b/internal/templatemanager/templatemanager.go
index 5effcb3..75309e4 100644
--- a/internal/templatemanager/templatemanager.go
+++ b/internal/templatemanager/templatemanager.go
@@ -22,22 +22,39 @@ type TemplateManagerTemplates struct {
 	Files []string
 }
 
-func NewTemplateManager(templates []TemplateManagerTemplates) (*TemplateManager, error) {
+var templateFuncMap = template.FuncMap{
+	"contains": strings.Contains,
+	"iterate": func(count uint) []uint {
+		items := make([]uint, count)
+		for i := range count {
+			items[i] = i
+		}
+		return items
+	},
+	"replace": strings.ReplaceAll,
+}
+
+func NewTemplateManager(templates ...TemplateManagerTemplates) (*TemplateManager, error) {
 	templateMap := make(map[string]templateManagerRender)
 
 	for _, tmplStruct := range templates {
-		tmpl := template.New("").Funcs(template.FuncMap{
-			"contains": strings.Contains,
-		})
+		tmpl := template.New(tmplStruct.Name).Funcs(templateFuncMap)
+		if len(tmplStruct.Files) == 0 {
+			templateMap[tmplStruct.Name] = templateManagerRender{
+				Main: "",
+				Tmpl: tmpl,
+			}
+			continue
+		}
 		tmpl, err := tmpl.ParseFiles(tmplStruct.Files...)
 		if err != nil {
 			return nil, err
 		}
+
 		templateMap[tmplStruct.Name] = templateManagerRender{
 			Main: filepath.Base(tmplStruct.Files[0]),
 			Tmpl: tmpl,
 		}
-
 	}
 
 	return &TemplateManager{
@@ -45,13 +62,59 @@ func NewTemplateManager(templates []TemplateManagerTemplates) (*TemplateManager,
 	}, nil
 }
 
-func (tm *TemplateManager) Render(name string, data interface{}) ([]byte, error) {
+func (tm *TemplateManager) Render(name string, data any, files ...string) ([]byte, error) {
 	tmpl, exists := tm.templates[name]
 	if !exists {
-		return nil, fmt.Errorf("template %s is not found", name)
+		return nil, fmt.Errorf("template %s not found", name)
+	}
+
+	var err error
+	var tempTmpl *template.Template
+	var mainTmpl string = tmpl.Main
+	if len(files) == 0 {
+		if mainTmpl == "" {
+			return []byte{}, nil
+		}
+		tempTmpl = tmpl.Tmpl
+	} else {
+		tempTmpl, err = tmpl.Tmpl.Clone()
+		if err != nil {
+			return nil, fmt.Errorf("couldn't clone existing template for rendering: %w", err)
+		}
+		tempTmpl, err = tempTmpl.ParseFiles(files...)
+		if err != nil {
+			return nil, fmt.Errorf("couldn't include additional files in template rendering: %w", err)
+		}
+		if mainTmpl == "" {
+			mainTmpl = filepath.Base(files[0])
+		}
 	}
 
 	var buf bytes.Buffer
-	err := tmpl.Tmpl.ExecuteTemplate(&buf, tmpl.Main, data)
+	err = tempTmpl.ExecuteTemplate(&buf, mainTmpl, data)
 	return buf.Bytes(), err
 }
+
+func (tm *TemplateManager) Add(name string, files ...string) error {
+	tmpl := template.New(name).Funcs(templateFuncMap)
+
+	if len(files) == 0 {
+		tm.templates[name] = templateManagerRender{
+			Main: "",
+			Tmpl: tmpl,
+		}
+		return nil
+	}
+
+	tmpl, err := tmpl.ParseFiles(files...)
+	if err != nil {
+		return fmt.Errorf("failed to add template into manager: %w", err)
+	}
+
+	tm.templates[name] = templateManagerRender{
+		Main: filepath.Base(files[0]),
+		Tmpl: tmpl,
+	}
+
+	return nil
+}