feat(tmedia): support MessageMediaInvoice (#581)

Extract paid media if possible.

pkg/tmedia/media.go

@@ -11,6 +11,18 @@ type Media struct {
  DC int
 }
 
+func extractMedia(m tg.MessageMediaClass) (*Media, bool) {
+ switch m := m.(type) {
+ case *tg.MessageMediaPhoto:
+ return GetPhotoInfo(m)
+ case *tg.MessageMediaDocument:
+ return GetDocumentInfo(m)
+ case *tg.MessageMediaInvoice:
+ return GetExtendedMedia(m.ExtendedMedia)
+ }
+ return nil, false
+}
+
 func GetMedia(msg tg.MessageClass) (*Media, bool) {
  mm, ok := msg.(*tg.Message)
  if !ok {
@@ -22,13 +34,15 @@ func GetMedia(msg tg.MessageClass) (*Media, bool) {
  return nil, false
  }
 
- switch m := media.(type) {
- case *tg.MessageMediaPhoto: // messageMediaPhoto#695150d7
- return GetPhotoInfo(m)
- case *tg.MessageMediaDocument: // messageMediaDocument#9cb070d7
- return GetDocumentInfo(m)
+ return extractMedia(media)
+}
+
+func GetExtendedMedia(mm tg.MessageExtendedMediaClass) (*Media, bool) {
+ m, ok := mm.(*tg.MessageExtendedMedia)
+ if !ok {
+ return nil, false
  }
- return nil, false
+ return extractMedia(m.Media)
 }
 
 func GetDocumentThumb(doc *tg.Document) (*Media, bool) {