tests/integration/test_error_handling_integration.py

"""
Integration tests for comprehensive error handling and logging.

Tests the complete error handling flow across all chat agent components
including circuit breaker integration, fallback responses, and logging.
"""

import pytest
import time
import json
import tempfile
import os
from unittest.mock import Mock, patch, MagicMock
from pathlib import Path

from chat_agent.services.groq_client import GroqClient, GroqError, GroqRateLimitError
from chat_agent.services.chat_agent import ChatAgent
from chat_agent.services.language_context import LanguageContextManager
from chat_agent.services.session_manager import SessionManager
from chat_agent.services.chat_history import ChatHistoryManager
from chat_agent.utils.error_handler import ChatAgentError, ErrorCategory, ErrorSeverity
from chat_agent.utils.circuit_breaker import CircuitState, get_circuit_breaker_manager
from chat_agent.utils.logging_config import setup_logging


class TestGroqClientErrorHandling:
    """Test error handling in Groq client with circuit breaker."""
    
    def setup_method(self):
        """Set up test fixtures."""
        # Setup logging to temporary directory
        self.temp_dir = tempfile.mkdtemp()
        os.environ['LOG_LEVEL'] = 'DEBUG'
        
        # Mock Groq API key
        os.environ['GROQ_API_KEY'] = 'test-api-key'
        
        # Create Groq client
        self.groq_client = GroqClient()
    
    def teardown_method(self):
        """Clean up test fixtures."""
        # Clean up temporary directory
        import shutil
        shutil.rmtree(self.temp_dir, ignore_errors=True)
    
    @patch('chat_agent.services.groq_client.Groq')
    @patch('chat_agent.services.groq_client.ChatGroq')
    def test_api_rate_limit_with_circuit_breaker(self, mock_chatgroq, mock_groq):
        """Test rate limit handling with circuit breaker protection."""
        from chat_agent.services.groq_client import ChatMessage, LanguageContext
        
        # Mock rate limit error
        mock_chatgroq.return_value.invoke.side_effect = Exception("Rate limit exceeded (429)")
        
        # Create test data
        prompt = "Test prompt"
        chat_history = []
        language_context = LanguageContext("python", "Test template", "python")
        
        # First few calls should trigger rate limit errors
        for i in range(3):
            try:
                response = self.groq_client.generate_response(prompt, chat_history, language_context)
                # Should return fallback response instead of raising
                assert "high demand" in response.lower()
            except Exception as e:
                # Some calls might still raise before circuit opens
                assert "rate limit" in str(e).lower()
        
        # Circuit breaker should be open now
        circuit_breaker = self.groq_client.circuit_breaker
        # Note: Circuit might not be open yet due to fallback handling
        # This tests the integration rather than exact circuit state
    
    @patch('chat_agent.services.groq_client.Groq')
    @patch('chat_agent.services.groq_client.ChatGroq')
    def test_api_authentication_error(self, mock_chatgroq, mock_groq):
        """Test authentication error handling."""
        from chat_agent.services.groq_client import ChatMessage, LanguageContext
        
        # Mock authentication error
        mock_chatgroq.return_value.invoke.side_effect = Exception("Authentication failed (401)")
        
        # Create test data
        prompt = "Test prompt"
        chat_history = []
        language_context = LanguageContext("python", "Test template", "python")
        
        # Should return fallback response for authentication errors
        response = self.groq_client.generate_response(prompt, chat_history, language_context)
        assert isinstance(response, str)
        assert len(response) > 0
    
    @patch('chat_agent.services.groq_client.Groq')
    def test_streaming_with_error_handling(self, mock_groq):
        """Test streaming response with error handling."""
        from chat_agent.services.groq_client import ChatMessage, LanguageContext
        
        # Mock streaming response that fails
        mock_response = Mock()
        mock_response.__iter__ = Mock(side_effect=Exception("Network error"))
        mock_groq.return_value.chat.completions.create.return_value = mock_response
        
        # Create test data
        prompt = "Test prompt"
        chat_history = []
        language_context = LanguageContext("python", "Test template", "python")
        
        # Should yield fallback response chunks
        chunks = list(self.groq_client.stream_response(prompt, chat_history, language_context))
        
        assert len(chunks) > 0
        full_response = "".join(chunks)
        assert len(full_response) > 0
        # Should contain fallback content
        assert any(word in full_response.lower() for word in ['programming', 'tips', 'try'])


class TestChatAgentErrorHandling:
    """Test error handling in chat agent service."""
    
    def setup_method(self):
        """Set up test fixtures."""
        # Setup logging
        self.loggers = setup_logging("test_chat_agent", "DEBUG")
        
        # Create mock dependencies
        self.mock_groq_client = Mock(spec=GroqClient)
        self.mock_language_manager = Mock(spec=LanguageContextManager)
        self.mock_session_manager = Mock(spec=SessionManager)
        self.mock_history_manager = Mock(spec=ChatHistoryManager)
        
        # Create chat agent
        self.chat_agent = ChatAgent(
            self.mock_groq_client,
            self.mock_language_manager,
            self.mock_session_manager,
            self.mock_history_manager
        )
    
    def test_session_error_handling(self):
        """Test handling of session-related errors."""
        from chat_agent.services.session_manager import SessionNotFoundError
        
        # Mock session not found error
        self.mock_session_manager.get_session.side_effect = SessionNotFoundError("Session not found")
        
        # Should handle session error gracefully
        with pytest.raises(ChatAgentError) as exc_info:
            self.chat_agent.process_message("invalid-session", "Test message")
        
        # Error should be properly classified
        error = exc_info.value
        assert isinstance(error, ChatAgentError)
    
    def test_chat_history_error_handling(self):
        """Test handling of chat history errors."""
        from chat_agent.services.chat_history import ChatHistoryError
        from chat_agent.models.chat_session import ChatSession
        
        # Mock successful session validation
        mock_session = Mock(spec=ChatSession)
        mock_session.language = "python"
        self.mock_session_manager.get_session.return_value = mock_session
        self.mock_language_manager.get_language.return_value = "python"
        
        # Mock chat history error
        self.mock_history_manager.store_message.side_effect = ChatHistoryError("Database error")
        
        # Should handle history error gracefully
        with pytest.raises(ChatAgentError) as exc_info:
            self.chat_agent.process_message("test-session", "Test message")
        
        error = exc_info.value
        assert isinstance(error, ChatAgentError)
    
    def test_groq_client_error_handling(self):
        """Test handling of Groq client errors."""
        from chat_agent.models.chat_session import ChatSession
        from chat_agent.models.message import Message
        
        # Mock successful setup
        mock_session = Mock(spec=ChatSession)
        mock_session.language = "python"
        self.mock_session_manager.get_session.return_value = mock_session
        self.mock_language_manager.get_language.return_value = "python"
        self.mock_language_manager.get_language_prompt_template.return_value = "Test template"
        
        mock_message = Mock(spec=Message)
        mock_message.id = "msg-123"
        self.mock_history_manager.store_message.return_value = mock_message
        self.mock_history_manager.get_recent_history.return_value = []
        
        # Mock Groq client error
        self.mock_groq_client.generate_response.side_effect = GroqRateLimitError("Rate limit exceeded")
        
        # Should handle Groq error and return fallback
        result = self.chat_agent.process_message("test-session", "Test message")
        
        # Should still return a valid response structure
        assert isinstance(result, dict)
        assert 'response' in result
        assert 'session_id' in result
    
    def test_language_switch_error_handling(self):
        """Test error handling during language switching."""
        from chat_agent.models.chat_session import ChatSession
        
        # Mock session
        mock_session = Mock(spec=ChatSession)
        mock_session.language = "python"
        self.mock_session_manager.get_session.return_value = mock_session
        
        # Mock language validation failure
        self.mock_language_manager.validate_language.return_value = False
        
        # Should handle invalid language gracefully
        with pytest.raises(ChatAgentError) as exc_info:
            self.chat_agent.switch_language("test-session", "invalid-language")
        
        error = exc_info.value
        assert "Unsupported language" in str(error)


class TestCircuitBreakerIntegration:
    """Test circuit breaker integration across services."""
    
    def setup_method(self):
        """Set up test fixtures."""
        self.circuit_manager = get_circuit_breaker_manager()
    
    def test_multiple_service_circuit_breakers(self):
        """Test circuit breakers across multiple services."""
        from chat_agent.utils.circuit_breaker import CircuitBreakerConfig
        
        # Create circuit breakers for different services
        groq_breaker = self.circuit_manager.create_breaker(
            "groq_service",
            CircuitBreakerConfig(failure_threshold=3, recovery_timeout=1)
        )
        
        db_breaker = self.circuit_manager.create_breaker(
            "database_service",
            CircuitBreakerConfig(failure_threshold=2, recovery_timeout=2)
        )
        
        # Test independent operation
        def groq_function():
            return "groq_response"
        
        def db_function():
            raise Exception("Database error")
        
        # Groq should work
        result = groq_breaker.call(groq_function)
        assert result == "groq_response"
        assert groq_breaker.is_closed
        
        # Database should fail and eventually open circuit
        for i in range(2):
            with pytest.raises(Exception):
                db_breaker.call(db_function)
        
        assert db_breaker.is_open
        assert groq_breaker.is_closed  # Should remain independent
    
    def test_circuit_breaker_statistics(self):
        """Test circuit breaker statistics collection."""
        from chat_agent.utils.circuit_breaker import CircuitBreakerConfig
        
        # Create test breaker
        breaker = self.circuit_manager.create_breaker(
            "stats_test",
            CircuitBreakerConfig(failure_threshold=2)
        )
        
        def success_function():
            return "success"
        
        def failure_function():
            raise ValueError("failure")
        
        # Execute mixed calls
        breaker.call(success_function)
        
        try:
            breaker.call(failure_function)
        except ValueError:
            pass
        
        breaker.call(success_function)
        
        # Check statistics
        stats = breaker.get_stats()
        assert stats.total_requests == 3
        assert stats.total_successes == 2
        assert stats.total_failures == 1
        
        # Check manager statistics
        all_stats = self.circuit_manager.get_all_stats()
        assert "stats_test" in all_stats
        assert all_stats["stats_test"].total_requests == 3


class TestLoggingIntegration:
    """Test logging integration across components."""
    
    def setup_method(self):
        """Set up test fixtures."""
        self.temp_dir = tempfile.mkdtemp()
        
        # Setup logging with temporary directory
        with patch('chat_agent.utils.logging_config.Path') as mock_path:
            mock_path.return_value.mkdir = Mock()
            mock_path.return_value.__truediv__ = lambda self, other: Path(self.temp_dir) / other
            
            self.loggers = setup_logging("test_integration", "DEBUG")
    
    def teardown_method(self):
        """Clean up test fixtures."""
        import shutil
        shutil.rmtree(self.temp_dir, ignore_errors=True)
    
    def test_structured_error_logging(self):
        """Test structured error logging across components."""
        error_logger = self.loggers['error']
        
        # Create test error with context
        error = ChatAgentError(
            message="Test integration error",
            category=ErrorCategory.API_ERROR,
            severity=ErrorSeverity.HIGH,
            context={
                'session_id': 'test-session-123',
                'operation': 'process_message',
                'duration': 2.5
            }
        )
        
        # Log error with extra context
        error_logger.error("Integration test error", extra={
            'error_code': error.error_code,
            'category': error.category.value,
            'severity': error.severity.value,
            'context': error.context,
            'session_id': 'test-session-123'
        })
        
        # Verify logging occurred (handlers would write to files in real scenario)
        assert len(error_logger.handlers) > 0
    
    def test_performance_logging_integration(self):
        """Test performance logging integration."""
        from chat_agent.utils.logging_config import get_performance_logger
        
        perf_logger = get_performance_logger('integration_test')
        
        # Log various operations
        perf_logger.log_operation("test_operation", 1.5, {
            'session_id': 'test-session',
            'language': 'python',
            'message_length': 100
        })
        
        perf_logger.log_api_call("/api/chat", "POST", 200, 0.8, {
            'session_id': 'test-session'
        })
        
        # Verify performance logger is working
        assert perf_logger.logger.name.endswith('integration_test')


class TestEndToEndErrorScenarios:
    """Test end-to-end error scenarios."""
    
    def setup_method(self):
        """Set up test fixtures."""
        # Setup comprehensive logging
        self.loggers = setup_logging("e2e_test", "DEBUG")
        
        # Create realistic mock setup
        self.setup_realistic_mocks()
    
    def setup_realistic_mocks(self):
        """Setup realistic mocks for end-to-end testing."""
        # Mock database and Redis connections
        self.mock_db = Mock()
        self.mock_redis = Mock()
        
        # Mock services with realistic behavior
        self.mock_groq_client = Mock(spec=GroqClient)
        self.mock_language_manager = Mock(spec=LanguageContextManager)
        self.mock_session_manager = Mock(spec=SessionManager)
        self.mock_history_manager = Mock(spec=ChatHistoryManager)
    
    def test_complete_service_failure_scenario(self):
        """Test complete service failure with graceful degradation."""
        from chat_agent.models.chat_session import ChatSession
        
        # Setup session that exists
        mock_session = Mock(spec=ChatSession)
        mock_session.language = "python"
        self.mock_session_manager.get_session.return_value = mock_session
        self.mock_language_manager.get_language.return_value = "python"
        
        # All services fail
        self.mock_history_manager.store_message.side_effect = Exception("Database down")
        self.mock_groq_client.generate_response.side_effect = Exception("API down")
        
        # Create chat agent
        chat_agent = ChatAgent(
            self.mock_groq_client,
            self.mock_language_manager,
            self.mock_session_manager,
            self.mock_history_manager
        )
        
        # Should handle complete failure gracefully
        with pytest.raises(ChatAgentError):
            chat_agent.process_message("test-session", "Test message")
    
    def test_partial_service_failure_scenario(self):
        """Test partial service failure with continued operation."""
        from chat_agent.models.chat_session import ChatSession
        from chat_agent.models.message import Message
        
        # Setup working session and language services
        mock_session = Mock(spec=ChatSession)
        mock_session.language = "python"
        self.mock_session_manager.get_session.return_value = mock_session
        self.mock_language_manager.get_language.return_value = "python"
        self.mock_language_manager.get_language_prompt_template.return_value = "Test template"
        
        # History service works
        mock_message = Mock(spec=Message)
        mock_message.id = "msg-123"
        self.mock_history_manager.store_message.return_value = mock_message
        self.mock_history_manager.get_recent_history.return_value = []
        
        # Only Groq service fails
        self.mock_groq_client.generate_response.return_value = "Fallback response from circuit breaker"
        
        # Create chat agent
        chat_agent = ChatAgent(
            self.mock_groq_client,
            self.mock_language_manager,
            self.mock_session_manager,
            self.mock_history_manager
        )
        
        # Should continue operating with fallback
        result = chat_agent.process_message("test-session", "Test message")
        
        assert isinstance(result, dict)
        assert 'response' in result
        assert result['response'] == "Fallback response from circuit breaker"
    
    def test_recovery_after_failure(self):
        """Test service recovery after failure."""
        from chat_agent.utils.circuit_breaker import CircuitBreakerConfig
        
        # Create circuit breaker with short recovery time
        circuit_manager = get_circuit_breaker_manager()
        breaker = circuit_manager.create_breaker(
            "recovery_test",
            CircuitBreakerConfig(
                failure_threshold=2,
                recovery_timeout=0.1,  # Very short for testing
                success_threshold=1
            )
        )
        
        # Function that fails then succeeds
        self.call_count = 0
        def flaky_function():
            self.call_count += 1
            if self.call_count <= 2:
                raise Exception("Service temporarily down")
            return "Service recovered"
        
        # Cause failures to open circuit
        for i in range(2):
            with pytest.raises(Exception):
                breaker.call(flaky_function)
        
        assert breaker.is_open
        
        # Wait for recovery timeout
        time.sleep(0.2)
        
        # Next call should succeed and close circuit
        result = breaker.call(flaky_function)
        assert result == "Service recovered"
        assert breaker.is_closed


if __name__ == '__main__':
    pytest.main([__file__])