# Tests for error handler module
import pytest
from unittest.mock import Mock, patch

from src.integration.error_handler import (
    ErrorHandler,
    ErrorType,
    ErrorContext,
    get_error_handler,
    reset_error_handler,
    handle_error,
)


class TestErrorType:
    """Tests for ErrorType enum."""
    
    def test_error_type_values(self):
        """Test error type enum values."""
        assert ErrorType.DATABASE_CONNECTION.value == "database_connection"
        assert ErrorType.DATABASE_QUERY.value == "database_query"
        assert ErrorType.SQL_VALIDATION.value == "sql_validation"
        assert ErrorType.SQL_INJECTION.value == "sql_injection"
        assert ErrorType.DOCUMENT_RETRIEVAL.value == "document_retrieval"
        assert ErrorType.LLM_GENERATION.value == "llm_generation"
        assert ErrorType.TIMEOUT.value == "timeout"
        assert ErrorType.UNKNOWN.value == "unknown"
    
    def test_error_type_membership(self):
        """Test all expected error types exist."""
        types = [t.value for t in ErrorType]
        assert "database_connection" in types
        assert "sql_injection" in types
        assert "timeout" in types
        assert "unknown" in types


class TestErrorContext:
    """Tests for ErrorContext dataclass."""
    
    def test_error_context_creation(self):
        """Test basic error context creation."""
        context = ErrorContext(
            error_type=ErrorType.DATABASE_QUERY,
            message="Query failed",
        )
        
        assert context.error_type == ErrorType.DATABASE_QUERY
        assert context.message == "Query failed"
        assert context.original_error is None
        assert context.query is None
    
    def test_error_context_with_all_fields(self):
        """Test error context with all fields."""
        original = ValueError("test error")
        context = ErrorContext(
            error_type=ErrorType.SQL_VALIDATION,
            message="Validation failed",
            original_error=original,
            query="SELECT * FROM table",
            additional_info={"key": "value"},
        )
        
        assert context.original_error == original
        assert context.query == "SELECT * FROM table"
        assert context.additional_info["key"] == "value"
    
    def test_error_context_to_dict(self):
        """Test conversion to dictionary."""
        original = ValueError("test")
        context = ErrorContext(
            error_type=ErrorType.TIMEOUT,
            message="Timed out",
            original_error=original,
            query="test query",
            additional_info={"timeout": 30},
        )
        
        result = context.to_dict()
        
        assert result["error_type"] == "timeout"
        assert result["message"] == "Timed out"
        assert result["query"] == "test query"
        assert result["original_error"] == "test"
        assert result["additional_info"]["timeout"] == 30
    
    def test_error_context_to_dict_no_original(self):
        """Test to_dict with no original error."""
        context = ErrorContext(
            error_type=ErrorType.UNKNOWN,
            message="Unknown error",
        )
        
        result = context.to_dict()
        assert result["original_error"] is None


class TestErrorHandler:
    """Tests for ErrorHandler class."""
    
    @pytest.fixture(autouse=True)
    def reset_handler(self):
        """Reset error handler before each test."""
        reset_error_handler()
        yield
        reset_error_handler()
    
    def test_error_handler_creation(self):
        """Test basic handler creation."""
        handler = ErrorHandler()
        
        assert handler.enable_fallback is True
        assert all(count == 0 for count in handler.error_counts.values())
    
    def test_error_handler_fallback_disabled(self):
        """Test handler with fallback disabled."""
        handler = ErrorHandler(enable_fallback=False)
        assert handler.enable_fallback is False
    
    def test_set_enable_fallback(self):
        """Test setting fallback enabled state."""
        handler = ErrorHandler()
        handler.enable_fallback = False
        assert handler.enable_fallback is False
    
    def test_error_counts_returns_copy(self):
        """Test that error_counts returns a copy."""
        handler = ErrorHandler()
        counts = handler.error_counts
        counts[ErrorType.UNKNOWN] = 999
        
        assert handler.error_counts[ErrorType.UNKNOWN] == 0
    
    def test_reset_counts(self):
        """Test resetting error counts."""
        handler = ErrorHandler()
        handler.handle(ValueError("test"))
        
        assert sum(handler.error_counts.values()) > 0
        handler.reset_counts()
        assert all(count == 0 for count in handler.error_counts.values())
    
    def test_handle_basic_error(self):
        """Test handling basic error."""
        handler = ErrorHandler()
        error = ValueError("test error")
        
        context = handler.handle(error)
        
        assert isinstance(context, ErrorContext)
        assert context.original_error == error
        assert context.message != ""
    
    def test_handle_with_error_type(self):
        """Test handling error with specified type."""
        handler = ErrorHandler()
        error = Exception("test")
        
        context = handler.handle(error, error_type=ErrorType.DATABASE_CONNECTION)
        
        assert context.error_type == ErrorType.DATABASE_CONNECTION
        assert handler.error_counts[ErrorType.DATABASE_CONNECTION] == 1
    
    def test_handle_with_query(self):
        """Test handling error with query context."""
        handler = ErrorHandler()
        error = Exception("test")
        
        context = handler.handle(error, query="SELECT * FROM users")
        
        assert context.query == "SELECT * FROM users"
    
    def test_handle_increments_count(self):
        """Test that handling increments error count."""
        handler = ErrorHandler()
        
        handler.handle(Exception("test1"), ErrorType.TIMEOUT)
        handler.handle(Exception("test2"), ErrorType.TIMEOUT)
        handler.handle(Exception("test3"), ErrorType.DATABASE_QUERY)
        
        assert handler.error_counts[ErrorType.TIMEOUT] == 2
        assert handler.error_counts[ErrorType.DATABASE_QUERY] == 1
    
    def test_get_user_message(self):
        """Test getting user-friendly messages."""
        handler = ErrorHandler()
        
        message = handler.get_user_message(ErrorType.DATABASE_CONNECTION)
        assert "bağlantı" in message.lower()
        
        message = handler.get_user_message(ErrorType.TIMEOUT)
        assert "zaman" in message.lower()
    
    def test_get_most_frequent_error_none(self):
        """Test most frequent error when no errors."""
        handler = ErrorHandler()
        assert handler.get_most_frequent_error() is None
    
    def test_get_most_frequent_error(self):
        """Test getting most frequent error type."""
        handler = ErrorHandler()
        
        handler.handle(Exception("1"), ErrorType.TIMEOUT)
        handler.handle(Exception("2"), ErrorType.TIMEOUT)
        handler.handle(Exception("3"), ErrorType.TIMEOUT)
        handler.handle(Exception("4"), ErrorType.DATABASE_QUERY)
        
        assert handler.get_most_frequent_error() == ErrorType.TIMEOUT
    
    def test_register_fallback(self):
        """Test registering fallback handler."""
        handler = ErrorHandler()
        fallback_fn = Mock(return_value="fallback result")
        
        handler.register_fallback(ErrorType.DATABASE_QUERY, fallback_fn)
        
        assert ErrorType.DATABASE_QUERY in handler._fallback_handlers
    
    def test_execute_with_fallback_success(self):
        """Test execute_with_fallback on success."""
        handler = ErrorHandler()
        
        def success_fn():
            return "success"
        
        result = handler.execute_with_fallback(
            success_fn,
            ErrorType.DATABASE_QUERY,
            fallback_value="fallback",
        )
        
        assert result == "success"
    
    def test_execute_with_fallback_uses_fallback_value(self):
        """Test execute_with_fallback uses fallback value on error."""
        handler = ErrorHandler()
        
        def failing_fn():
            raise ValueError("test error")
        
        result = handler.execute_with_fallback(
            failing_fn,
            ErrorType.DATABASE_QUERY,
            fallback_value="fallback result",
        )
        
        assert result == "fallback result"
    
    def test_execute_with_fallback_uses_registered_handler(self):
        """Test execute_with_fallback uses registered handler."""
        handler = ErrorHandler()
        fallback_fn = Mock(return_value="custom fallback")
        handler.register_fallback(ErrorType.DATABASE_QUERY, fallback_fn)
        
        def failing_fn():
            raise ValueError("test")
        
        result = handler.execute_with_fallback(
            failing_fn,
            ErrorType.DATABASE_QUERY,
            fallback_value="default",
            query="test query",
        )
        
        assert result == "custom fallback"
        fallback_fn.assert_called_once()
    
    def test_execute_with_fallback_disabled(self):
        """Test execute_with_fallback when fallback disabled."""
        handler = ErrorHandler(enable_fallback=False)
        fallback_fn = Mock(return_value="custom")
        handler.register_fallback(ErrorType.DATABASE_QUERY, fallback_fn)
        
        def failing_fn():
            raise ValueError("test")
        
        result = handler.execute_with_fallback(
            failing_fn,
            ErrorType.DATABASE_QUERY,
            fallback_value="default",
        )
        
        assert result == "default"
        fallback_fn.assert_not_called()


class TestErrorTypeDetection:
    """Tests for automatic error type detection."""
    
    @pytest.fixture(autouse=True)
    def reset_handler(self):
        """Reset error handler before each test."""
        reset_error_handler()
        yield
        reset_error_handler()
    
    def test_detect_connection_error(self):
        """Test detection of connection errors."""
        handler = ErrorHandler()
        
        error = Exception("Connection refused")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.DATABASE_CONNECTION
    
    def test_detect_timeout_error(self):
        """Test detection of timeout errors."""
        handler = ErrorHandler()
        
        error = Exception("Query timed out after 30 seconds")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.TIMEOUT
    
    def test_detect_injection_error(self):
        """Test detection of SQL injection errors."""
        handler = ErrorHandler()
        
        error = Exception("SQL injection detected, forbidden pattern")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.SQL_INJECTION
    
    def test_detect_validation_error(self):
        """Test detection of validation errors."""
        handler = ErrorHandler()
        
        error = Exception("Validation failed: invalid data")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.SQL_VALIDATION
    
    def test_detect_retrieval_error(self):
        """Test detection of document retrieval errors."""
        handler = ErrorHandler()
        
        error = Exception("Failed to retrieve documents")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.DOCUMENT_RETRIEVAL
    
    def test_detect_llm_error(self):
        """Test detection of LLM errors."""
        handler = ErrorHandler()
        
        error = Exception("LLM generation failed")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.LLM_GENERATION
    
    def test_detect_unknown_error(self):
        """Test detection of unknown errors."""
        handler = ErrorHandler()
        
        error = Exception("Some random error")
        context = handler.handle(error)
        
        assert context.error_type == ErrorType.UNKNOWN


class TestErrorHandlerSingleton:
    """Tests for error handler singleton functions."""
    
    @pytest.fixture(autouse=True)
    def reset_singleton(self):
        """Reset singleton before each test."""
        reset_error_handler()
        yield
        reset_error_handler()
    
    def test_get_error_handler_creates_instance(self):
        """Test get_error_handler creates new instance."""
        handler = get_error_handler()
        assert handler is not None
        assert isinstance(handler, ErrorHandler)
    
    def test_get_error_handler_returns_same_instance(self):
        """Test get_error_handler returns singleton."""
        handler1 = get_error_handler()
        handler2 = get_error_handler()
        assert handler1 is handler2
    
    def test_reset_error_handler(self):
        """Test reset_error_handler clears singleton."""
        handler1 = get_error_handler()
        reset_error_handler()
        handler2 = get_error_handler()
        
        assert handler1 is not handler2
    
    def test_handle_error_convenience_function(self):
        """Test handle_error convenience function."""
        error = ValueError("test")
        context = handle_error(error, ErrorType.DATABASE_QUERY, "test query")
        
        assert context.error_type == ErrorType.DATABASE_QUERY
        assert context.query == "test query"
    
    def test_handle_error_uses_singleton(self):
        """Test handle_error uses singleton handler."""
        handle_error(ValueError("test1"), ErrorType.TIMEOUT)
        handle_error(ValueError("test2"), ErrorType.TIMEOUT)
        
        handler = get_error_handler()
        assert handler.error_counts[ErrorType.TIMEOUT] == 2


class TestErrorMessages:
    """Tests for error message localization."""
    
    def test_all_error_types_have_messages(self):
        """Test all error types have user messages."""
        handler = ErrorHandler()
        
        for error_type in ErrorType:
            message = handler.get_user_message(error_type)
            assert message != ""
            assert len(message) > 10
    
    def test_messages_are_turkish(self):
        """Test messages contain Turkish text."""
        handler = ErrorHandler()
        
        message = handler.get_user_message(ErrorType.DATABASE_CONNECTION)
        turkish_chars = set("ğüşıöçĞÜŞİÖÇ")
        message_lower = message.lower()
        
        turkish_words = ["lütfen", "veritabanı", "sorgu", "hata", "işlem"]
        has_turkish = any(word in message_lower for word in turkish_words)
        assert has_turkish


class TestErrorContext:
    """Additional tests for error context."""
    
    def test_error_context_includes_traceback(self):
        """Test error context includes traceback in additional_info."""
        handler = ErrorHandler()
        
        try:
            raise ValueError("test error")
        except Exception as e:
            context = handler.handle(e)
        
        assert context.additional_info is not None
        assert "traceback" in context.additional_info
        assert "ValueError" in context.additional_info["traceback"]