package template import ( _ "embed" "errors" "fmt" html "html/template" "io" "io/fs" "os" text "text/template" "github.com/Necoro/feed2imap-go/pkg/log" ) type template interface { Execute(wr io.Writer, data interface{}) error Name() string } type Template struct { template useHtml bool dflt string } //go:embed html.tpl var defaultHtmlTpl string //go:embed text.tpl var defaultTextTpl string var Html = Template{ useHtml: true, dflt: defaultHtmlTpl, template: html.New("Html").Funcs(funcMap), } var Text = Template{ useHtml: false, dflt: defaultTextTpl, template: text.New("Text").Funcs(funcMap), } func (tpl *Template) loadDefault() { if err := tpl.load(tpl.dflt); err != nil { panic(err) } } func (tpl *Template) load(content string) (err error) { if tpl.useHtml { _, err = tpl.template.(*html.Template).Parse(content) } else { _, err = tpl.template.(*text.Template).Parse(content) } return } func (tpl *Template) LoadFile(file string) error { content, err := os.ReadFile(file) if err != nil { if errors.Is(err, fs.ErrNotExist) { log.Errorf("Template file '%s' does not exist, keeping default.", file) return nil } else { return fmt.Errorf("reading template file '%s': %w", file, err) } } return tpl.load(string(content)) } func init() { Html.loadDefault() Text.loadDefault() }