wip: handling speaker_id and language in coqui TTS backend

backend/python/coqui/coqui_server.py

@@ -66,7 +66,19 @@ def LoadModel(self, request, context):
 
     def TTS(self, request, context):
         try:
-            self.tts.tts_to_file(text=request.text, speaker_wav=self.AudioPath, language=COQUI_LANGUAGE, file_path=request.dst)
+            # if model is multilangual add language from request or env as fallback
+            lang = request.Lang or COQUI_LANGUAGE
+            if self.tts.is_multi_lingual and lang is None:
+               return backend_pb2.Result(success=False, message=f"Model is multi-lingual, but no language was provided")
+
+            # if model is multi-speaker, use speaker_wav or the speaker_id from request.voice
+            if self.tts.is_multi_speaker and self.AudioPath is None and request.voice is None:
+                return backend_pb2.Result(success=False, message=f"Model is multi-speaker, but no speaker was provided")
+
+            if self.tts.is_multi_speaker and request.voice is not None:
+               self.tts.tts_to_file(text=request.text, speaker=request.voice, language=lang, file_path=request.dst)
+            else:
+                self.tts.tts_to_file(text=request.text, speaker_wav=self.AudioPath, language=lang, file_path=request.dst)
         except Exception as err:
             return backend_pb2.Result(success=False, message=f"Unexpected {err=}, {type(err)=}")
         return backend_pb2.Result(success=True)