import os
import sys

sys.path.insert(0, os.path.abspath("../.."))

import pytest

from litellm.integrations.posthog import PostHogLogger
from litellm.types.utils import StandardLoggingPayload
from typing import cast

# Set env vars for tests
os.environ["POSTHOG_API_KEY"] = "test_key"
os.environ["POSTHOG_API_URL"] = "https://app.posthog.com"


def create_standard_logging_payload() -> StandardLoggingPayload:
    # Use cast to bypass strict TypedDict requirements for tests
    return cast(
        StandardLoggingPayload,
        {
            "id": "test_id",
            "trace_id": "test_trace_id",
            "call_type": "completion",
            "stream": False,
            "response_cost": 0.1,
            "status": "success",
            "custom_llm_provider": "openai",
            "total_tokens": 30,
            "prompt_tokens": 20,
            "completion_tokens": 10,
            "startTime": 1234567890.0,
            "endTime": 1234567891.0,
            "completionStartTime": 1234567890.5,
            "response_time": 1.0,
            "model": "gpt-3.5-turbo",
            "model_id": "model-123",
            "api_base": "https://api.openai.com",
            "cache_hit": False,
            "saved_cache_cost": 0.0,
            "request_tags": [],
            "end_user": None,
            "messages": [{"role": "user", "content": "Hello, world!"}],
            "response": {"choices": [{"message": {"content": "Hi there!"}}]},
            "error_str": None,
            "model_parameters": {"stream": True},
        },
    )


@pytest.mark.asyncio
async def test_create_posthog_event_payload():
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()
    kwargs = {"standard_logging_object": standard_payload}

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    assert event_payload["event"] == "$ai_generation"
    assert event_payload["properties"]["$ai_model"] == "gpt-3.5-turbo"
    assert event_payload["properties"]["$ai_input_tokens"] == 20
    assert event_payload["properties"]["$ai_output_tokens"] == 10


@pytest.mark.asyncio
async def test_posthog_failure_logging():
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()
    standard_payload["status"] = "failure"
    standard_payload["error_str"] = "Test error"

    kwargs = {"standard_logging_object": standard_payload}

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    assert event_payload["properties"]["$ai_is_error"] is True
    assert event_payload["properties"]["$ai_error"] == "Test error"


@pytest.mark.asyncio
async def test_posthog_embedding_event():
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()
    standard_payload["call_type"] = "embedding"

    kwargs = {"standard_logging_object": standard_payload}

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    assert event_payload["event"] == "$ai_embedding"
    assert "$ai_output_tokens" not in event_payload["properties"]


@pytest.mark.asyncio
async def test_trace_id_fallback_from_standard_logging_object():
    """Test that trace_id is properly extracted from standard_logging_object"""
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()
    standard_payload["trace_id"] = "test-trace-123"

    kwargs = {"standard_logging_object": standard_payload}

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    assert event_payload["properties"]["$ai_trace_id"] == "test-trace-123"
    assert (
        event_payload["properties"]["$ai_span_id"] == "test_id"
    )  # from standard_payload["id"]


@pytest.mark.asyncio
async def test_trace_id_uuid_fallback():
    """Test that UUID is generated when no trace_id is available"""
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()
    # Remove trace_id to test fallback
    del standard_payload["trace_id"]
    del standard_payload["id"]

    kwargs = {"standard_logging_object": standard_payload}

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    # Should have generated UUIDs
    assert len(event_payload["properties"]["$ai_trace_id"]) == 36  # UUID length
    assert len(event_payload["properties"]["$ai_span_id"]) == 36  # UUID length
    assert "-" in event_payload["properties"]["$ai_trace_id"]  # UUID format


@pytest.mark.asyncio
async def test_distinct_id_fallback_chain():
    """Test the distinct_id fallback priority chain"""
    posthog_logger = PostHogLogger()

    # Test 1: user_id from metadata (highest priority)
    standard_payload = create_standard_logging_payload()
    kwargs = {
        "standard_logging_object": standard_payload,
        "litellm_params": {"metadata": {"user_id": "metadata-user-123"}},
    }

    distinct_id = posthog_logger._get_distinct_id(standard_payload, kwargs)
    assert distinct_id == "metadata-user-123"

    # Test 2: trace_id from standard_logging_object (second priority)
    kwargs = {"standard_logging_object": standard_payload}  # no metadata
    distinct_id = posthog_logger._get_distinct_id(standard_payload, kwargs)
    assert distinct_id == "test_trace_id"

    # Test 3: end_user from standard_logging_object (third priority)
    standard_payload_no_trace = create_standard_logging_payload()
    del standard_payload_no_trace["trace_id"]
    standard_payload_no_trace["end_user"] = "end-user-456"

    distinct_id = posthog_logger._get_distinct_id(standard_payload_no_trace, {})
    assert distinct_id == "end-user-456"

    # Test 4: UUID fallback (lowest priority)
    standard_payload_empty = create_standard_logging_payload()
    del standard_payload_empty["trace_id"]
    del standard_payload_empty["end_user"]

    distinct_id = posthog_logger._get_distinct_id(standard_payload_empty, {})
    assert len(distinct_id) == 36  # UUID length
    assert "-" in distinct_id  # UUID format


@pytest.mark.asyncio
async def test_missing_standard_logging_object():
    """Test error handling when standard_logging_object is missing"""
    posthog_logger = PostHogLogger()

    kwargs = {}  # Missing standard_logging_object

    with pytest.raises(ValueError, match="standard_logging_object not found in kwargs"):
        posthog_logger.create_posthog_event_payload(kwargs)


@pytest.mark.asyncio
async def test_custom_metadata_support():
    """Test that custom metadata fields are added directly to properties"""
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()

    kwargs = {
        "standard_logging_object": standard_payload,
        "litellm_params": {
            "metadata": {
                "user_id": "user-123",  # should be used for distinct_id, not custom property
                "project_name": "test_project",  # should appear as project_name
                "environment": "staging",  # should appear as environment
                "custom_field": "custom_value",  # should appear as custom_field
            }
        },
    }

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    # Check that custom fields are added directly
    assert event_payload["properties"]["project_name"] == "test_project"
    assert event_payload["properties"]["environment"] == "staging"
    assert event_payload["properties"]["custom_field"] == "custom_value"

    # Check that user_id is used for distinct_id, not as custom property
    assert event_payload["distinct_id"] == "user-123"
    assert "user_id" not in event_payload["properties"]


@pytest.mark.asyncio
async def test_custom_metadata_filters_internal_fields():
    """Test that LiteLLM internal fields are filtered out from custom metadata"""
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()

    kwargs = {
        "standard_logging_object": standard_payload,
        "litellm_params": {
            "metadata": {
                "custom_field": "should_appear",
                "endpoint": "/chat/completions",  # internal field - should be filtered
                "user_api_key_hash": "hash123",  # internal field - should be filtered
                "headers": {
                    "content-type": "application/json"
                },  # internal field - should be filtered
                "model_info": {"id": "123"},  # internal field - should be filtered
            }
        },
    }

    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    # Check that custom field appears
    assert event_payload["properties"]["custom_field"] == "should_appear"

    # Check that internal fields are filtered out
    assert "endpoint" not in event_payload["properties"]
    assert "user_api_key_hash" not in event_payload["properties"]
    assert "headers" not in event_payload["properties"]
    assert "model_info" not in event_payload["properties"]


@pytest.mark.asyncio
async def test_custom_metadata_with_no_metadata():
    """Test that logger handles cases with no metadata gracefully"""
    posthog_logger = PostHogLogger()
    standard_payload = create_standard_logging_payload()

    # Test with no litellm_params
    kwargs = {"standard_logging_object": standard_payload}
    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    # Should not error and should have standard properties
    assert event_payload["event"] == "$ai_generation"
    assert event_payload["properties"]["$ai_model"] == "gpt-3.5-turbo"

    # Test with empty metadata
    kwargs = {
        "standard_logging_object": standard_payload,
        "litellm_params": {"metadata": {}},
    }
    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    # Should not error and should have standard properties
    assert event_payload["event"] == "$ai_generation"
    assert event_payload["properties"]["$ai_model"] == "gpt-3.5-turbo"


@pytest.mark.asyncio
async def test_dynamic_credentials():
    """Test that per-request credentials override environment variables"""
    from litellm.types.utils import StandardCallbackDynamicParams

    posthog_logger = PostHogLogger()

    # Test with no dynamic params - should use env vars
    kwargs = {}
    api_key, api_url = posthog_logger._get_credentials_for_request(kwargs)
    assert api_key == "test_key"  # from env var
    assert api_url == "https://app.posthog.com"  # from env var

    # Test with dynamic params - should override env vars
    standard_callback_dynamic_params = StandardCallbackDynamicParams(
        posthog_api_key="dynamic_key", posthog_api_url="https://custom.posthog.com"
    )
    kwargs = {"standard_callback_dynamic_params": standard_callback_dynamic_params}
    api_key, api_url = posthog_logger._get_credentials_for_request(kwargs)
    assert api_key == "dynamic_key"
    assert api_url == "https://custom.posthog.com"

    # Test partial override - only api_key
    standard_callback_dynamic_params = StandardCallbackDynamicParams(
        posthog_api_key="another_key"
    )
    kwargs = {"standard_callback_dynamic_params": standard_callback_dynamic_params}
    api_key, api_url = posthog_logger._get_credentials_for_request(kwargs)
    assert api_key == "another_key"
    assert api_url == "https://app.posthog.com"  # falls back to env var

    # Test partial override - only api_url
    standard_callback_dynamic_params = StandardCallbackDynamicParams(
        posthog_api_url="https://another.posthog.com"
    )
    kwargs = {"standard_callback_dynamic_params": standard_callback_dynamic_params}
    api_key, api_url = posthog_logger._get_credentials_for_request(kwargs)
    assert api_key == "test_key"  # falls back to env var
    assert api_url == "https://another.posthog.com"


def test_async_callback_atexit_handler_exists():
    """
    Test that atexit handlers are properly registered.

    This test verifies that both GLOBAL_LOGGING_WORKER and PostHogLogger
    register atexit handlers for flushing pending events.

    The actual functionality is validated by end-to-end tests (test_async_only.py)
    since unit testing atexit behavior across event loop boundaries is complex.
    """
    import atexit
    from litellm.litellm_core_utils.logging_worker import GLOBAL_LOGGING_WORKER

    # Verify GLOBAL_LOGGING_WORKER has _flush_on_exit method
    assert hasattr(GLOBAL_LOGGING_WORKER, '_flush_on_exit'), \
        "GLOBAL_LOGGING_WORKER should have _flush_on_exit method"

    # Verify PostHogLogger has _flush_on_exit method
    posthog_logger = PostHogLogger()
    assert hasattr(posthog_logger, '_flush_on_exit'), \
        "PostHogLogger should have _flush_on_exit method"

    # Verify method can be called without crashing (with empty queue)
    # This tests the early return paths
    GLOBAL_LOGGING_WORKER._flush_on_exit()
    posthog_logger._flush_on_exit()


@pytest.mark.asyncio
async def test_posthog_atexit_flushes_internal_queue():
    """
    Test that PostHog's atexit handler flushes its internal log_queue.

    This works in conjunction with GLOBAL_LOGGING_WORKER:
    1. GLOBAL_LOGGING_WORKER atexit invokes pending callbacks
    2. Callbacks add events to PostHog's internal log_queue
    3. PostHog's atexit flushes log_queue via HTTP POST
    """
    from unittest.mock import Mock, patch
    import httpx

    posthog_logger = PostHogLogger()

    # Add mock events to internal queue (simulating what callbacks do)
    standard_payload = create_standard_logging_payload()
    kwargs = {"standard_logging_object": standard_payload}
    event_payload = posthog_logger.create_posthog_event_payload(kwargs)

    posthog_logger.log_queue.append({
        "event": event_payload,
        "api_key": "test_key",
        "api_url": "https://app.posthog.com"
    })

    assert len(posthog_logger.log_queue) == 1, "Queue should have 1 event"

    # Mock the sync HTTP client to avoid real API calls
    with patch.object(posthog_logger.sync_client, 'post') as mock_post:
        mock_response = Mock()
        mock_response.status_code = 200
        mock_response.raise_for_status = Mock()
        mock_post.return_value = mock_response

        # Trigger atexit flush
        posthog_logger._flush_on_exit()

        # Verify HTTP POST was called
        assert mock_post.called, "HTTP POST should be called during flush"
        assert len(posthog_logger.log_queue) == 0, "Queue should be empty after flush"

        # Verify correct endpoint was called
        call_args = mock_post.call_args
        assert "/batch/" in call_args.kwargs['url'], "Should POST to /batch/ endpoint"


@pytest.mark.asyncio
async def test_sync_callback_not_affected_by_atexit():
    """
    Regression test: ensure sync completions still work immediately.

    Sync callbacks should be invoked immediately during completion(),
    not deferred to atexit. This test verifies atexit handlers don't
    interfere with the sync path.
    """
    from unittest.mock import Mock, patch

    # Track when callback is invoked
    callback_invoked_immediately = False

    def mock_log_success(self, kwargs, response_obj, start_time, end_time):
        nonlocal callback_invoked_immediately
        callback_invoked_immediately = True

    with patch.object(PostHogLogger, 'log_success_event', mock_log_success):
        with patch('httpx.Client.post') as mock_post:
            mock_response = Mock()
            mock_response.status_code = 200
            mock_response.raise_for_status = Mock()
            mock_post.return_value = mock_response

            posthog_logger = PostHogLogger()
            standard_payload = create_standard_logging_payload()
            kwargs = {"standard_logging_object": standard_payload}

            # Call sync method directly (simulates what completion() does)
            posthog_logger.log_success_event(kwargs, None, 0.0, 0.0)

            # Callback should be invoked immediately, not queued for atexit
            assert callback_invoked_immediately, "Sync callback should be invoked immediately"