"""
Integration tests for WebSocket streaming functionality.

Tests WebSocket connections, message handling, and real-time data streaming.
"""

import pytest
import asyncio
import json
from datetime import datetime
from typing import Dict, Any, List
from unittest.mock import AsyncMock, MagicMock, patch

import websockets
from fastapi import FastAPI, WebSocket
from fastapi.testclient import TestClient


class MockWebSocket:
    """Mock WebSocket for testing."""
    
    def __init__(self):
        self.messages_sent = []
        self.messages_received = []
        self.closed = False
        self.accept_called = False
    
    async def accept(self):
        """Mock accept method."""
        self.accept_called = True
    
    async def send_json(self, data: Dict[str, Any]):
        """Mock send_json method."""
        self.messages_sent.append(data)
    
    async def send_text(self, text: str):
        """Mock send_text method."""
        self.messages_sent.append(text)
    
    async def receive_text(self) -> str:
        """Mock receive_text method."""
        if self.messages_received:
            return self.messages_received.pop(0)
        # Simulate WebSocket disconnect
        from fastapi import WebSocketDisconnect
        raise WebSocketDisconnect()
    
    async def close(self):
        """Mock close method."""
        self.closed = True
    
    def add_received_message(self, message: str):
        """Add a message to be received."""
        self.messages_received.append(message)


class TestWebSocketStreaming:
    """Integration tests for WebSocket streaming."""
    
    @pytest.fixture
    def mock_websocket(self):
        """Create mock WebSocket."""
        return MockWebSocket()
    
    @pytest.fixture
    def mock_connection_manager(self):
        """Mock connection manager."""
        manager = AsyncMock()
        manager.connect.return_value = "client-001"
        manager.disconnect.return_value = True
        manager.get_connection_stats.return_value = {
            "total_clients": 1,
            "active_streams": ["pose"]
        }
        manager.broadcast.return_value = 1
        return manager
    
    @pytest.fixture
    def mock_stream_service(self):
        """Mock stream service."""
        service = AsyncMock()
        service.get_status.return_value = {
            "is_active": True,
            "active_streams": [],
            "uptime_seconds": 3600.0
        }
        service.is_active.return_value = True
        service.start.return_value = None
        service.stop.return_value = None
        return service
    
    @pytest.mark.asyncio
    async def test_websocket_pose_connection_should_fail_initially(self, mock_websocket, mock_connection_manager):
        """Test WebSocket pose connection establishment - should fail initially."""
        # This test should fail because we haven't implemented the WebSocket handler properly
        
        # Simulate WebSocket connection
        zone_ids = "zone1,zone2"
        min_confidence = 0.7
        max_fps = 30
        
        # Mock the websocket_pose_stream function
        async def mock_websocket_handler(websocket, zone_ids, min_confidence, max_fps):
            await websocket.accept()
            
            # Parse zone IDs
            zone_list = [zone.strip() for zone in zone_ids.split(",") if zone.strip()]
            
            # Register client
            client_id = await mock_connection_manager.connect(
                websocket=websocket,
                stream_type="pose",
                zone_ids=zone_list,
                min_confidence=min_confidence,
                max_fps=max_fps
            )
            
            # Send confirmation
            await websocket.send_json({
                "type": "connection_established",
                "client_id": client_id,
                "timestamp": datetime.utcnow().isoformat(),
                "config": {
                    "zone_ids": zone_list,
                    "min_confidence": min_confidence,
                    "max_fps": max_fps
                }
            })
            
            return client_id
        
        # Execute the handler
        client_id = await mock_websocket_handler(mock_websocket, zone_ids, min_confidence, max_fps)
        
        # This assertion will fail initially, driving us to implement the WebSocket handler
        assert mock_websocket.accept_called
        assert len(mock_websocket.messages_sent) == 1
        assert mock_websocket.messages_sent[0]["type"] == "connection_established"
        assert mock_websocket.messages_sent[0]["client_id"] == "client-001"
        assert "config" in mock_websocket.messages_sent[0]
    
    @pytest.mark.asyncio
    async def test_websocket_message_handling_should_fail_initially(self, mock_websocket):
        """Test WebSocket message handling - should fail initially."""
        # Mock message handler
        async def handle_websocket_message(client_id: str, data: Dict[str, Any], websocket):
            message_type = data.get("type")
            
            if message_type == "ping":
                await websocket.send_json({
                    "type": "pong",
                    "timestamp": datetime.utcnow().isoformat()
                })
            elif message_type == "update_config":
                config = data.get("config", {})
                await websocket.send_json({
                    "type": "config_updated",
                    "timestamp": datetime.utcnow().isoformat(),
                    "config": config
                })
            else:
                await websocket.send_json({
                    "type": "error",
                    "message": f"Unknown message type: {message_type}"
                })
        
        # Test ping message
        ping_data = {"type": "ping"}
        await handle_websocket_message("client-001", ping_data, mock_websocket)
        
        # This will fail initially
        assert len(mock_websocket.messages_sent) == 1
        assert mock_websocket.messages_sent[0]["type"] == "pong"
        
        # Test config update
        mock_websocket.messages_sent.clear()
        config_data = {
            "type": "update_config",
            "config": {"min_confidence": 0.8, "max_fps": 15}
        }
        await handle_websocket_message("client-001", config_data, mock_websocket)
        
        # This will fail initially
        assert len(mock_websocket.messages_sent) == 1
        assert mock_websocket.messages_sent[0]["type"] == "config_updated"
        assert mock_websocket.messages_sent[0]["config"]["min_confidence"] == 0.8
    
    @pytest.mark.asyncio
    async def test_websocket_events_stream_should_fail_initially(self, mock_websocket, mock_connection_manager):
        """Test WebSocket events stream - should fail initially."""
        # Mock events stream handler
        async def mock_events_handler(websocket, event_types, zone_ids):
            await websocket.accept()
            
            # Parse parameters
            event_list = [event.strip() for event in event_types.split(",") if event.strip()] if event_types else None
            zone_list = [zone.strip() for zone in zone_ids.split(",") if zone.strip()] if zone_ids else None
            
            # Register client
            client_id = await mock_connection_manager.connect(
                websocket=websocket,
                stream_type="events",
                zone_ids=zone_list,
                event_types=event_list
            )
            
            # Send confirmation
            await websocket.send_json({
                "type": "connection_established",
                "client_id": client_id,
                "timestamp": datetime.utcnow().isoformat(),
                "config": {
                    "event_types": event_list,
                    "zone_ids": zone_list
                }
            })
            
            return client_id
        
        # Execute handler
        client_id = await mock_events_handler(mock_websocket, "fall_detection,intrusion", "zone1")
        
        # This will fail initially
        assert mock_websocket.accept_called
        assert len(mock_websocket.messages_sent) == 1
        assert mock_websocket.messages_sent[0]["type"] == "connection_established"
        assert mock_websocket.messages_sent[0]["config"]["event_types"] == ["fall_detection", "intrusion"]
    
    @pytest.mark.asyncio
    async def test_websocket_disconnect_handling_should_fail_initially(self, mock_websocket, mock_connection_manager):
        """Test WebSocket disconnect handling - should fail initially."""
        # Mock disconnect scenario
        client_id = "client-001"
        
        # Simulate disconnect
        disconnect_result = await mock_connection_manager.disconnect(client_id)
        
        # This will fail initially
        assert disconnect_result is True
        mock_connection_manager.disconnect.assert_called_once_with(client_id)


class TestWebSocketConnectionManager:
    """Test WebSocket connection management."""
    
    @pytest.fixture
    def connection_manager(self):
        """Create connection manager for testing."""
        # Mock connection manager implementation
        class MockConnectionManager:
            def __init__(self):
                self.connections = {}
                self.client_counter = 0
            
            async def connect(self, websocket, stream_type, zone_ids=None, **kwargs):
                self.client_counter += 1
                client_id = f"client-{self.client_counter:03d}"
                self.connections[client_id] = {
                    "websocket": websocket,
                    "stream_type": stream_type,
                    "zone_ids": zone_ids or [],
                    "connected_at": datetime.utcnow(),
                    **kwargs
                }
                return client_id
            
            async def disconnect(self, client_id):
                if client_id in self.connections:
                    del self.connections[client_id]
                    return True
                return False
            
            async def get_connected_clients(self):
                return list(self.connections.keys())
            
            async def get_connection_stats(self):
                return {
                    "total_clients": len(self.connections),
                    "active_streams": list(set(conn["stream_type"] for conn in self.connections.values()))
                }
            
            async def broadcast(self, data, stream_type=None, zone_ids=None):
                sent_count = 0
                for client_id, conn in self.connections.items():
                    if stream_type and conn["stream_type"] != stream_type:
                        continue
                    if zone_ids and not any(zone in conn["zone_ids"] for zone in zone_ids):
                        continue
                    
                    # Mock sending data
                    sent_count += 1
                
                return sent_count
        
        return MockConnectionManager()
    
    @pytest.mark.asyncio
    async def test_connection_manager_connect_should_fail_initially(self, connection_manager, mock_websocket):
        """Test connection manager connect functionality - should fail initially."""
        client_id = await connection_manager.connect(
            websocket=mock_websocket,
            stream_type="pose",
            zone_ids=["zone1", "zone2"],
            min_confidence=0.7
        )
        
        # This will fail initially
        assert client_id == "client-001"
        assert client_id in connection_manager.connections
        assert connection_manager.connections[client_id]["stream_type"] == "pose"
        assert connection_manager.connections[client_id]["zone_ids"] == ["zone1", "zone2"]
    
    @pytest.mark.asyncio
    async def test_connection_manager_disconnect_should_fail_initially(self, connection_manager, mock_websocket):
        """Test connection manager disconnect functionality - should fail initially."""
        # Connect first
        client_id = await connection_manager.connect(
            websocket=mock_websocket,
            stream_type="pose"
        )
        
        # Disconnect
        result = await connection_manager.disconnect(client_id)
        
        # This will fail initially
        assert result is True
        assert client_id not in connection_manager.connections
    
    @pytest.mark.asyncio
    async def test_connection_manager_broadcast_should_fail_initially(self, connection_manager):
        """Test connection manager broadcast functionality - should fail initially."""
        # Connect multiple clients
        ws1 = MockWebSocket()
        ws2 = MockWebSocket()
        
        client1 = await connection_manager.connect(ws1, "pose", zone_ids=["zone1"])
        client2 = await connection_manager.connect(ws2, "events", zone_ids=["zone2"])
        
        # Broadcast to pose stream
        sent_count = await connection_manager.broadcast(
            data={"type": "pose_data", "data": {}},
            stream_type="pose"
        )
        
        # This will fail initially
        assert sent_count == 1
        
        # Broadcast to specific zone
        sent_count = await connection_manager.broadcast(
            data={"type": "zone_event", "data": {}},
            zone_ids=["zone1"]
        )
        
        # This will fail initially
        assert sent_count == 1


class TestWebSocketPerformance:
    """Test WebSocket performance characteristics."""
    
    @pytest.mark.asyncio
    async def test_multiple_concurrent_connections_should_fail_initially(self):
        """Test handling multiple concurrent WebSocket connections - should fail initially."""
        # Mock multiple connections
        connection_count = 10
        connections = []
        
        for i in range(connection_count):
            mock_ws = MockWebSocket()
            connections.append(mock_ws)
        
        # Simulate concurrent connections
        async def simulate_connection(websocket, client_id):
            await websocket.accept()
            await websocket.send_json({
                "type": "connection_established",
                "client_id": client_id
            })
            return True
        
        # Execute concurrent connections
        tasks = [
            simulate_connection(ws, f"client-{i:03d}")
            for i, ws in enumerate(connections)
        ]
        
        results = await asyncio.gather(*tasks)
        
        # This will fail initially
        assert len(results) == connection_count
        assert all(results)
        assert all(ws.accept_called for ws in connections)
    
    @pytest.mark.asyncio
    async def test_websocket_message_throughput_should_fail_initially(self):
        """Test WebSocket message throughput - should fail initially."""
        mock_ws = MockWebSocket()
        message_count = 100
        
        # Simulate high-frequency message sending
        start_time = datetime.utcnow()
        
        for i in range(message_count):
            await mock_ws.send_json({
                "type": "pose_data",
                "frame_id": f"frame-{i:04d}",
                "timestamp": datetime.utcnow().isoformat()
            })
        
        end_time = datetime.utcnow()
        duration = (end_time - start_time).total_seconds()
        
        # This will fail initially
        assert len(mock_ws.messages_sent) == message_count
        assert duration < 1.0  # Should handle 100 messages in under 1 second
        
        # Calculate throughput
        throughput = message_count / duration if duration > 0 else float('inf')
        assert throughput > 100  # Should handle at least 100 messages per second