"""
Tests for app/tasks/monitor_stalled_steps.py

This module tests the periodic task that monitors and recovers stalled processing steps.
"""

from unittest.mock import MagicMock, patch

import pytest


@pytest.mark.unit
class TestMonitorStalledSteps:
    """Test monitor_stalled_steps task."""

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    def test_monitor_stalled_steps_no_stalled(self, mock_session_local, mock_mark_stalled):
        """Test monitor_stalled_steps when no stalled steps found."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_session_local.return_value.__enter__.return_value = mock_db

        # No stalled steps
        mock_mark_stalled.return_value = 0

        # Run task
        result = monitor_stalled_steps()

        # Verify result
        assert result == {"recovered": 0}
        mock_mark_stalled.assert_called_once_with(mock_db)

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    def test_monitor_stalled_steps_with_stalled(self, mock_session_local, mock_mark_stalled):
        """Test monitor_stalled_steps when stalled steps are found."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_session_local.return_value.__enter__.return_value = mock_db

        # Found 3 stalled steps
        mock_mark_stalled.return_value = 3

        # Run task
        result = monitor_stalled_steps()

        # Verify result
        assert result == {"recovered": 3}
        mock_mark_stalled.assert_called_once_with(mock_db)

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    @patch("app.tasks.monitor_stalled_steps.logger")
    def test_monitor_stalled_steps_logs_recovery(self, mock_logger, mock_session_local, mock_mark_stalled):
        """Test that monitor_stalled_steps logs recovery actions."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_session_local.return_value.__enter__.return_value = mock_db

        # Found 2 stalled steps
        mock_mark_stalled.return_value = 2

        # Run task
        result = monitor_stalled_steps()

        # Verify logging
        mock_logger.warning.assert_called_once()
        log_message = mock_logger.warning.call_args[0][0]
        assert "Recovered 2 stalled step(s)" in log_message

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    @patch("app.tasks.monitor_stalled_steps.logger")
    def test_monitor_stalled_steps_logs_debug_when_none(self, mock_logger, mock_session_local, mock_mark_stalled):
        """Test that monitor_stalled_steps logs debug message when no stalled steps."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_session_local.return_value.__enter__.return_value = mock_db

        # No stalled steps
        mock_mark_stalled.return_value = 0

        # Run task
        result = monitor_stalled_steps()

        # Verify debug logging
        mock_logger.debug.assert_called_once()
        log_message = mock_logger.debug.call_args[0][0]
        assert "No stalled steps found" in log_message

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    @patch("app.tasks.monitor_stalled_steps.logger")
    def test_monitor_stalled_steps_handles_exceptions(self, mock_logger, mock_session_local, mock_mark_stalled):
        """Test that monitor_stalled_steps handles exceptions gracefully."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_session_local.return_value.__enter__.return_value = mock_db

        # Simulate an exception
        mock_mark_stalled.side_effect = Exception("Database error")

        # Run task
        result = monitor_stalled_steps()

        # Verify error handling
        assert result == {"error": "Database error", "recovered": 0}
        mock_logger.error.assert_called_once()

    @patch("app.tasks.monitor_stalled_steps.mark_stalled_steps_as_failed")
    @patch("app.tasks.monitor_stalled_steps.SessionLocal")
    def test_monitor_stalled_steps_uses_context_manager(self, mock_session_local, mock_mark_stalled):
        """Test that monitor_stalled_steps uses context manager for database session."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Mock database session
        mock_db = MagicMock()
        mock_context = MagicMock()
        mock_context.__enter__ = MagicMock(return_value=mock_db)
        mock_context.__exit__ = MagicMock(return_value=False)
        mock_session_local.return_value = mock_context

        mock_mark_stalled.return_value = 0

        # Run task
        result = monitor_stalled_steps()

        # Verify context manager was used
        mock_context.__enter__.assert_called_once()
        mock_context.__exit__.assert_called_once()

    def test_monitor_stalled_steps_is_celery_task(self):
        """Test that monitor_stalled_steps is registered as a Celery task."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Should have task attributes
        assert hasattr(monitor_stalled_steps, "apply_async")
        assert hasattr(monitor_stalled_steps, "delay")
        assert callable(monitor_stalled_steps)

    def test_monitor_stalled_steps_task_name(self):
        """Test that monitor_stalled_steps has correct task name."""
        from app.tasks.monitor_stalled_steps import monitor_stalled_steps

        # Check task name
        assert monitor_stalled_steps.name == "app.tasks.monitor_stalled_steps.monitor_stalled_steps"