tests/unit/domain/services/test_audio_processing_service.py

"""Tests for AudioProcessingService."""

import pytest
from unittest.mock import Mock, MagicMock
from src.domain.services.audio_processing_service import AudioProcessingService
from src.domain.models.audio_content import AudioContent
from src.domain.models.text_content import TextContent
from src.domain.models.voice_settings import VoiceSettings
from src.domain.models.translation_request import TranslationRequest
from src.domain.models.speech_synthesis_request import SpeechSynthesisRequest
from src.domain.exceptions import (
    AudioProcessingException,
    SpeechRecognitionException,
    TranslationFailedException,
    SpeechSynthesisException
)


class TestAudioProcessingService:
    """Test cases for AudioProcessingService."""

    @pytest.fixture
    def mock_stt_service(self):
        """Mock speech recognition service."""
        return Mock()

    @pytest.fixture
    def mock_translation_service(self):
        """Mock translation service."""
        return Mock()

    @pytest.fixture
    def mock_tts_service(self):
        """Mock speech synthesis service."""
        return Mock()

    @pytest.fixture
    def audio_processing_service(self, mock_stt_service, mock_translation_service, mock_tts_service):
        """AudioProcessingService instance with mocked dependencies."""
        return AudioProcessingService(
            speech_recognition_service=mock_stt_service,
            translation_service=mock_translation_service,
            speech_synthesis_service=mock_tts_service
        )

    @pytest.fixture
    def sample_audio(self):
        """Sample audio content for testing."""
        return AudioContent(
            data=b"fake_audio_data",
            format="wav",
            sample_rate=22050,
            duration=10.0,
            filename="test.wav"
        )

    @pytest.fixture
    def sample_voice_settings(self):
        """Sample voice settings for testing."""
        return VoiceSettings(
            voice_id="test_voice",
            speed=1.0,
            language="es"
        )

    @pytest.fixture
    def sample_text_content(self):
        """Sample text content for testing."""
        return TextContent(
            text="Hello world",
            language="en"
        )

    def test_successful_pipeline_processing(
        self,
        audio_processing_service,
        mock_stt_service,
        mock_translation_service,
        mock_tts_service,
        sample_audio,
        sample_voice_settings,
        sample_text_content
    ):
        """Test successful processing through the complete pipeline."""
        # Arrange
        original_text = TextContent(text="Hello world", language="en")
        translated_text = TextContent(text="Hola mundo", language="es")
        output_audio = AudioContent(
            data=b"synthesized_audio",
            format="wav",
            sample_rate=22050,
            duration=5.0
        )

        mock_stt_service.transcribe.return_value = original_text
        mock_translation_service.translate.return_value = translated_text
        mock_tts_service.synthesize.return_value = output_audio

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is True
        assert result.original_text == original_text
        assert result.translated_text == translated_text
        assert result.audio_output == output_audio
        assert result.error_message is None
        assert result.processing_time >= 0

        # Verify service calls
        mock_stt_service.transcribe.assert_called_once_with(sample_audio, "whisper-base")
        mock_translation_service.translate.assert_called_once()
        mock_tts_service.synthesize.assert_called_once()

    def test_no_translation_needed_same_language(
        self,
        audio_processing_service,
        mock_stt_service,
        mock_translation_service,
        mock_tts_service,
        sample_audio
    ):
        """Test pipeline when no translation is needed (same language)."""
        # Arrange
        original_text = TextContent(text="Hola mundo", language="es")
        voice_settings = VoiceSettings(voice_id="test_voice", speed=1.0, language="es")
        output_audio = AudioContent(
            data=b"synthesized_audio",
            format="wav",
            sample_rate=22050,
            duration=5.0
        )

        mock_stt_service.transcribe.return_value = original_text
        mock_tts_service.synthesize.return_value = output_audio

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=voice_settings
        )

        # Assert
        assert result.success is True
        assert result.original_text == original_text
        assert result.translated_text == original_text  # Same as original
        assert result.audio_output == output_audio

        # Translation service should not be called
        mock_translation_service.translate.assert_not_called()

    def test_validation_error_none_audio(self, audio_processing_service, sample_voice_settings):
        """Test validation error when audio is None."""
        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=None,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "Audio content cannot be None" in result.error_message

    def test_validation_error_empty_target_language(self, audio_processing_service, sample_audio, sample_voice_settings):
        """Test validation error when target language is empty."""
        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "Target language cannot be empty" in result.error_message

    def test_validation_error_language_mismatch(self, audio_processing_service, sample_audio):
        """Test validation error when voice settings language doesn't match target language."""
        # Arrange
        voice_settings = VoiceSettings(voice_id="test_voice", speed=1.0, language="en")

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=voice_settings
        )

        # Assert
        assert result.success is False
        assert "Voice settings language (en) must match target language (es)" in result.error_message

    def test_validation_error_audio_too_long(self, audio_processing_service, sample_voice_settings):
        """Test validation error when audio is too long."""
        # Arrange
        long_audio = AudioContent(
            data=b"fake_audio_data",
            format="wav",
            sample_rate=22050,
            duration=400.0  # Exceeds 300s limit
        )

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=long_audio,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "exceeds maximum allowed duration" in result.error_message

    def test_stt_failure_handling(
        self,
        audio_processing_service,
        mock_stt_service,
        sample_audio,
        sample_voice_settings
    ):
        """Test handling of STT service failure."""
        # Arrange
        mock_stt_service.transcribe.side_effect = Exception("STT service unavailable")

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "Speech recognition failed" in result.error_message
        assert result.processing_time >= 0

    def test_translation_failure_handling(
        self,
        audio_processing_service,
        mock_stt_service,
        mock_translation_service,
        sample_audio,
        sample_voice_settings
    ):
        """Test handling of translation service failure."""
        # Arrange
        original_text = TextContent(text="Hello world", language="en")
        mock_stt_service.transcribe.return_value = original_text
        mock_translation_service.translate.side_effect = Exception("Translation service unavailable")

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "Translation failed" in result.error_message
        assert result.processing_time >= 0

    def test_tts_failure_handling(
        self,
        audio_processing_service,
        mock_stt_service,
        mock_translation_service,
        mock_tts_service,
        sample_audio,
        sample_voice_settings
    ):
        """Test handling of TTS service failure."""
        # Arrange
        original_text = TextContent(text="Hello world", language="en")
        translated_text = TextContent(text="Hola mundo", language="es")

        mock_stt_service.transcribe.return_value = original_text
        mock_translation_service.translate.return_value = translated_text
        mock_tts_service.synthesize.side_effect = Exception("TTS service unavailable")

        # Act
        result = audio_processing_service.process_audio_pipeline(
            audio=sample_audio,
            target_language="es",
            voice_settings=sample_voice_settings
        )

        # Assert
        assert result.success is False
        assert "Speech synthesis failed" in result.error_message
        assert result.processing_time >= 0