4 files changed, 178 insertions, 1 deletions

diff --git a/tests/cover_test.png b/tests/cover_test.png
index c6c4bc6..0c252db 100644
--- a/tests/cover_test.png
+++ b/tests/cover_test.png
diff --git a/tests/gen_test_cover.py b/tests/gen_test_cover.py
index 7c9347e..292469a 100644
--- a/tests/gen_test_cover.py
+++ b/tests/gen_test_cover.py
@@ -3,6 +3,6 @@ from pathlib import Path
 sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
 from converter.cover import generate_cover
 
-p = generate_cover('Your Book Title Here',
+p = generate_cover('The Count of Monte Cristo',
                    Path(__file__).resolve().parent / 'cover_test.png')
 print('written:', p)
diff --git a/tests/test_converter.py b/tests/test_converter.py
index 91ce699..351849a 100644
--- a/tests/test_converter.py
+++ b/tests/test_converter.py
@@ -34,6 +34,27 @@ class ConfigurationValidationTests(unittest.TestCase):
         with self.assertRaises(ValueError):
             AudiobookConverter(output_format="wma")
 
+    def test_unknown_language_rejected(self):
+        with self.assertRaises(ValueError):
+            AudiobookConverter(language="klingon")
+
+    def test_language_defaults_to_config(self):
+        with patch("converter.converter.QwenTTSClient") as mock_tts:
+            AudiobookConverter()
+        self.assertEqual(mock_tts.call_args.kwargs["language"], "English")
+
+    def test_output_format_defaults_to_config(self):
+        with patch("converter.converter.QwenTTSClient"):
+            converter = AudiobookConverter()
+        self.assertEqual(converter.output_format, config.AUDIO_FORMAT)
+        self.assertEqual(config.AUDIO_FORMAT, "m4b")
+
+    def test_language_normalized_before_tts_client(self):
+        with patch("converter.converter.QwenTTSClient") as mock_tts:
+            converter = AudiobookConverter(language="ja")
+        self.assertEqual(converter.language, "Japanese")
+        self.assertEqual(mock_tts.call_args.kwargs["language"], "Japanese")
+
 
 class FindExistingOutputsTests(unittest.TestCase):
     def setUp(self):
@@ -127,6 +148,7 @@ class RunOverwritePromptTests(unittest.TestCase):
         self.converter.speed = 1.0
         self.converter.single_file = False
         self.converter.output_format = "mp3"
+        self.converter.language = "English"
         self.converted = []
         self.converter.convert_book = (
             lambda file_path, output_name=None:
diff --git a/tests/test_tts.py b/tests/test_tts.py
new file mode 100644
index 0000000..b605daa
--- /dev/null
+++ b/tests/test_tts.py
@@ -0,0 +1,155 @@
+"""Tests for the Qwen TTS client wrapper (language handling and payloads)."""
+
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+from converter import config
+from converter.tts import QwenTTSClient, normalize_language
+
+
+class NormalizeLanguageTests(unittest.TestCase):
+    def test_display_names_case_insensitive(self):
+        self.assertEqual(normalize_language("english"), "English")
+        self.assertEqual(normalize_language("ENGLISH"), "English")
+        self.assertEqual(normalize_language(" Japanese "), "Japanese")
+
+    def test_auto_accepted(self):
+        self.assertEqual(normalize_language("auto"), "Auto")
+        self.assertEqual(normalize_language("Auto"), "Auto")
+
+    def test_iso_aliases(self):
+        self.assertEqual(normalize_language("en"), "English")
+        self.assertEqual(normalize_language("ja"), "Japanese")
+        self.assertEqual(normalize_language("zh"), "Chinese")
+        self.assertEqual(normalize_language("ko"), "Korean")
+        self.assertEqual(normalize_language("de"), "German")
+        self.assertEqual(normalize_language("fr"), "French")
+        self.assertEqual(normalize_language("ru"), "Russian")
+        self.assertEqual(normalize_language("pt"), "Portuguese")
+        self.assertEqual(normalize_language("es"), "Spanish")
+        self.assertEqual(normalize_language("it"), "Italian")
+
+    def test_all_supported_languages_round_trip(self):
+        for name in config.TTS_LANGUAGES:
+            self.assertEqual(normalize_language(name.lower()), name)
+
+    def test_unknown_language_rejected_with_guidance(self):
+        with self.assertRaises(ValueError) as ctx:
+            normalize_language("klingon")
+        message = str(ctx.exception)
+        self.assertIn("klingon", message)
+        self.assertIn("English", message)
+
+    def test_none_and_empty_rejected(self):
+        with self.assertRaises(ValueError):
+            normalize_language(None)
+        with self.assertRaises(ValueError):
+            normalize_language("   ")
+
+
+class QwenTTSClientLanguageTests(unittest.TestCase):
+    """Language validation and defaults, without touching the network."""
+
+    def _make_client(self, **kwargs):
+        with patch.object(QwenTTSClient, "_connect"):
+            return QwenTTSClient(**kwargs)
+
+    def test_default_follows_config_for_each_mode(self):
+        custom = self._make_client(voice_mode=config.VOICE_MODE_CUSTOM)
+        self.assertEqual(custom.language, config.CUSTOM_VOICE_LANGUAGE)
+        clone = self._make_client(voice_mode=config.VOICE_MODE_CLONE,
+                                  voice_clone_ref_audio="ref.wav")
+        self.assertEqual(clone.language, config.VOICE_CLONE_LANGUAGE)
+
+    def test_explicit_language_normalized(self):
+        client = self._make_client(voice_mode=config.VOICE_MODE_CUSTOM, language="ja")
+        self.assertEqual(client.language, "Japanese")
+
+    def test_invalid_language_fails_before_connect(self):
+        with patch.object(QwenTTSClient, "_connect") as mock_connect:
+            with self.assertRaises(ValueError):
+                QwenTTSClient(language="klingon")
+        mock_connect.assert_not_called()
+
+
+class PayloadLanguageTests(unittest.TestCase):
+    """The language must reach the API payload in every endpoint variant."""
+
+    def setUp(self):
+        self._tmp = tempfile.TemporaryDirectory()
+        self.ref_audio = Path(self._tmp.name) / "reference.wav"
+        self.ref_audio.write_bytes(b"x")
+
+    def tearDown(self):
+        self._tmp.cleanup()
+
+    def _custom_client(self, language, endpoint, api_info=None):
+        client = QwenTTSClient.__new__(QwenTTSClient)
+        client.voice_mode = config.VOICE_MODE_CUSTOM
+        client.language = language
+        client.api_info = api_info if api_info is not None else {
+            "named_endpoints": {endpoint: {}}
+        }
+        client.client = MagicMock()
+        return client
+
+    def _clone_client(self, language, endpoint, api_info=None, ref_text="hello"):
+        client = QwenTTSClient.__new__(QwenTTSClient)
+        client.voice_mode = config.VOICE_MODE_CLONE
+        client.language = language
+        client.voice_clone_ref_audio = str(self.ref_audio)
+        client.voice_clone_ref_text = ref_text
+        client.clone_api_info = api_info if api_info is not None else {
+            "named_endpoints": {endpoint: {}}
+        }
+        client.clone_client = MagicMock()
+        client._ref_audio_filedata = {"dummy": "payload"}
+        return client
+
+    def test_custom_voice_run_instruct_uses_language(self):
+        client = self._custom_client("Japanese", "/run_instruct")
+        client._generate_custom_voice("text")
+        kwargs = client.client.predict.call_args.kwargs
+        self.assertEqual(kwargs["lang_disp"], "Japanese")
+
+    def test_custom_voice_alt_endpoint_uses_language(self):
+        client = self._custom_client("French", "/run_custom_voice")
+        client._generate_custom_voice("text")
+        kwargs = client.client.predict.call_args.kwargs
+        self.assertEqual(kwargs["language"], "French")
+
+    def test_voice_clone_run_voice_clone_uses_language(self):
+        client = self._clone_client("Japanese", "/run_voice_clone")
+        client._generate_voice_clone("text")
+        kwargs = client.clone_client.predict.call_args.kwargs
+        self.assertEqual(kwargs["lang_disp"], "Japanese")
+
+    def test_voice_clone_alt_endpoint_uses_language(self):
+        client = self._clone_client("Korean", "/generate_voice_clone")
+        client._generate_voice_clone("text")
+        kwargs = client.clone_client.predict.call_args.kwargs
+        self.assertEqual(kwargs["language"], "Korean")
+
+    def test_voice_clone_alt_endpoint_includes_optional_params(self):
+        api_info = {
+            "named_endpoints": {
+                "/generate_voice_clone": {
+                    "parameters": [
+                        {"parameter_name": "model_size"},
+                        {"parameter_name": "seed"},
+                    ]
+                }
+            }
+        }
+        client = self._clone_client("English", "/generate_voice_clone", api_info=api_info)
+        client._generate_voice_clone("text")
+        kwargs = client.clone_client.predict.call_args.kwargs
+        self.assertEqual(kwargs["model_size"], config.VOICE_CLONE_MODEL_SIZE)
+        self.assertEqual(kwargs["seed"], config.VOICE_CLONE_SEED)
+        self.assertNotIn("max_chunk_chars", kwargs)
+
+
+if __name__ == "__main__":
+    unittest.main()