"""
Unit tests for DatabaseWatchdog.
"""

import pytest
from unittest.mock import Mock, AsyncMock, patch
from datetime import datetime, timedelta

from src.monitoring.watchdog import DatabaseWatchdog


class TestDatabaseWatchdog:
    """Test cases for DatabaseWatchdog."""
    
    def setup_method(self):
        """Set up test fixtures."""
        self.mock_db_client = Mock()
        self.mock_db_client.execute = Mock()
        self.mock_db_client.get_latest_pump_plans = Mock()
        self.mock_db_client.get_pump = Mock()
        self.mock_alert_manager = Mock()
        
        self.watchdog = DatabaseWatchdog(self.mock_db_client, self.mock_alert_manager, timeout_seconds=300)  # 5 minutes for testing
    
    @pytest.mark.asyncio
    async def test_start_stop(self):
        """Test starting and stopping the watchdog."""
        # Act
        await self.watchdog.start()
        
        # Assert
        assert self.watchdog.running is True
        
        # Act
        await self.watchdog.stop()
        
        # Assert
        assert self.watchdog.running is False
    
    @pytest.mark.asyncio
    async def test_check_updates_fresh_plans(self):
        """Test checking updates with fresh plans."""
        # Arrange
        recent_time = datetime.now() - timedelta(minutes=1)
        self.mock_db_client.get_latest_pump_plans.return_value = [
            {
                'station_id': 'STATION_001',
                'pump_id': 'PUMP_001',
                'plan_updated_at': recent_time
            }
        ]
        
        # Act
        await self.watchdog._check_updates()
        
        # Assert
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is False
        assert self.mock_db_client.get_latest_pump_plans.called
    
    @pytest.mark.asyncio
    async def test_check_updates_stale_plans(self):
        """Test checking updates with stale plans."""
        # Arrange
        stale_time = datetime.now() - timedelta(minutes=10)  # 10 minutes old
        self.mock_db_client.get_latest_pump_plans.return_value = [
            {
                'station_id': 'STATION_001',
                'pump_id': 'PUMP_001',
                'plan_updated_at': stale_time
            }
        ]
        self.mock_db_client.get_pump.return_value = {
            'default_setpoint_hz': 30.0
        }
        
        # Act
        await self.watchdog._check_updates()
        
        # Assert
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is True
        assert self.mock_db_client.execute.called  # Should record failsafe event
    
    @pytest.mark.asyncio
    async def test_check_updates_no_plans(self):
        """Test checking updates when no plans exist."""
        # Arrange
        self.mock_db_client.get_latest_pump_plans.return_value = []
        
        # Act
        await self.watchdog._check_updates()
        
        # Assert
        assert self.mock_db_client.get_latest_pump_plans.called
        # Should not trigger failsafe immediately
    
    @pytest.mark.asyncio
    async def test_activate_failsafe(self):
        """Test activating failsafe mode."""
        # Arrange
        self.mock_db_client.get_pump.return_value = {
            'default_setpoint_hz': 30.0
        }
        
        # Act
        await self.watchdog._activate_failsafe('STATION_001', 'PUMP_001', 350)
        
        # Assert
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is True
        assert self.mock_db_client.execute.called
    
    @pytest.mark.asyncio
    async def test_deactivate_failsafe(self):
        """Test deactivating failsafe mode."""
        # Arrange
        await self.watchdog._activate_failsafe('STATION_001', 'PUMP_001', 350)
        
        # Act
        await self.watchdog._deactivate_failsafe('STATION_001', 'PUMP_001')
        
        # Assert
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is False
        assert self.mock_db_client.execute.call_count == 2  # Activation + deactivation
    
    @pytest.mark.asyncio
    async def test_failsafe_recovery(self):
        """Test failsafe recovery when updates resume."""
        # Arrange - First check with stale plans (trigger failsafe)
        stale_time = datetime.now() - timedelta(minutes=10)
        self.mock_db_client.get_latest_pump_plans.return_value = [
            {
                'station_id': 'STATION_001',
                'pump_id': 'PUMP_001',
                'plan_updated_at': stale_time
            }
        ]
        self.mock_db_client.get_pump.return_value = {'default_setpoint_hz': 30.0}
        
        await self.watchdog._check_updates()
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is True
        
        # Arrange - Second check with fresh plans (should recover)
        recent_time = datetime.now() - timedelta(minutes=1)
        self.mock_db_client.get_latest_pump_plans.return_value = [
            {
                'station_id': 'STATION_001',
                'pump_id': 'PUMP_001',
                'plan_updated_at': recent_time
            }
        ]
        
        # Act
        await self.watchdog._check_updates()
        
        # Assert
        assert self.watchdog.is_failsafe_active('STATION_001', 'PUMP_001') is False
    
    def test_get_last_update_time(self):
        """Test getting last update time."""
        # Arrange
        test_time = datetime.now()
        self.watchdog.last_update_times[('STATION_001', 'PUMP_001')] = test_time
        
        # Act
        result = self.watchdog.get_last_update_time('STATION_001', 'PUMP_001')
        
        # Assert
        assert result == test_time
    
    def test_get_status(self):
        """Test getting watchdog status."""
        # Arrange
        test_time = datetime.now() - timedelta(minutes=2)
        self.watchdog.last_update_times[('STATION_001', 'PUMP_001')] = test_time
        self.watchdog.failsafe_active[('STATION_001', 'PUMP_001')] = False
        
        # Act
        status = self.watchdog.get_status()
        
        # Assert
        assert status['running'] is False  # Not started yet
        assert status['timeout_seconds'] == 300
        assert status['monitored_pumps'] == 1
        assert status['failsafe_active_pumps'] == 0
        assert 'STATION_001_PUMP_001' in status['pump_status']