import websockets
import json
import numpy as np
from typing import Dict, Any, Optional, Union
import threading
from queue import Queue
import time
import asyncio
import hashlib

class WebSocketGPUStorage:
    # Singleton instance
    _instance = None
    _lock = threading.Lock()

    def __new__(cls, url: str = "wss://factorst-wbs1.hf.space/ws"):
        with cls._lock:
            if cls._instance is None:
                cls._instance = super().__new__(cls)
                cls._instance._init_singleton(url)
            return cls._instance

    def _init_singleton(self, url: str):
        """Initialize the singleton instance"""
        if hasattr(self, 'initialized'):
            return
        
        self.url = url
        self.websocket = None
        self.connected = False
        self.message_queue = Queue()
        self.response_queues: Dict[str, Queue] = {}
        self.lock = threading.Lock()
        self._closing = False
        self._loop = None
        self.error_count = 0
        self.last_error_time = 0
        self.max_retries = 5
        self.tensor_registry: Dict[str, Dict[str, Any]] = {}  # Track tensor metadata
        self.model_registry: Dict[str, Dict[str, Any]] = {}  # Track loaded models
        self.resource_monitor = {
            'vram_used': 0,
            'active_tensors': 0,
            'loaded_models': set()
        }
        
        # Start WebSocket connection in a separate thread
        self.ws_thread = threading.Thread(target=self._run_websocket_loop, daemon=True)
        self.ws_thread.start()
        self.initialized = True
        
    def __init__(self, url: str = "wss://factorst-wbs1.hf.space/ws"):
        """This will actually just return the singleton instance"""
        pass

    def _run_websocket_loop(self):
        self._loop = asyncio.new_event_loop()
        asyncio.set_event_loop(self._loop)
        self._loop.run_until_complete(self._websocket_handler())

    async def _websocket_handler(self):
        while not self._closing:
            try:
                async with websockets.connect(self.url) as websocket:
                    self.websocket = websocket
                    self.connected = True
                    self.error_count = 0  # Reset error count on successful connection
                    print("Connected to GPU storage server")

                    while True:
                        # Handle outgoing messages
                        try:
                            while not self.message_queue.empty():
                                msg_id, operation = self.message_queue.get()
                                await websocket.send(json.dumps(operation))
                                
                                # Wait for response with timeout
                                try:
                                    response = await asyncio.wait_for(websocket.recv(), timeout=30)
                                    response_data = json.loads(response)
                                    
                                    # Put response in corresponding queue
                                    if msg_id in self.response_queues:
                                        self.response_queues[msg_id].put(response_data)
                                except asyncio.TimeoutError:
                                    if msg_id in self.response_queues:
                                        self.response_queues[msg_id].put({
                                            "status": "error",
                                            "message": "Operation timed out"
                                        })
                                except Exception as e:
                                    if msg_id in self.response_queues:
                                        self.response_queues[msg_id].put({
                                            "status": "error",
                                            "message": f"Error processing response: {str(e)}"
                                        })

                        except Exception as e:
                            print(f"Error processing message: {str(e)}")

                        # Keep connection alive with heartbeat
                        try:
                            await websocket.ping()
                        except:
                            break  # Break inner loop on ping failure
                            
                        await asyncio.sleep(0.001)  # 1ms sleep for electron-speed response

            except Exception as e:
                print(f"WebSocket connection error: {e}")
                self.connected = False
                await asyncio.sleep(1)  # Wait before reconnecting

    def _send_operation(self, operation: Dict[str, Any]) -> Dict[str, Any]:
        if self._closing:
            return {"status": "error", "message": "WebSocket is closing"}
            
        if not self.wait_for_connection(timeout=10):
            return {"status": "error", "message": "Not connected to GPU storage server"}
            
        msg_id = str(time.time())
        response_queue = Queue()
        
        with self.lock:
            self.response_queues[msg_id] = response_queue
            self.message_queue.put((msg_id, operation))
        
        try:
            # Wait for response with configurable timeout
            response = response_queue.get(timeout=30)  # Extended timeout for large models
            if response.get("status") == "error" and "model_size" in operation:
                # Retry once for model loading operations
                self.message_queue.put((msg_id, operation))
                response = response_queue.get(timeout=30)
        except Exception as e:
            response = {"status": "error", "message": f"Operation failed: {str(e)}"}
        finally:
            with self.lock:
                if msg_id in self.response_queues:
                    del self.response_queues[msg_id]
            
        return response

    def store_tensor(self, tensor_id: str, data: np.ndarray, model_size: Optional[int] = None) -> bool:
        try:
            if data is None:
                raise ValueError("Cannot store None tensor")
                
            # Calculate tensor metadata
            tensor_shape = data.shape
            tensor_dtype = str(data.dtype)
            tensor_size = data.nbytes
            
            operation = {
                'operation': 'vram',
                'type': 'write',
                'block_id': tensor_id,
                'data': data.tolist(),
                'model_size': model_size if model_size is not None else -1,  # -1 indicates unlimited
                'metadata': {
                    'shape': tensor_shape,
                    'dtype': tensor_dtype,
                    'size': tensor_size,
                    'timestamp': time.time()
                }
            }
            
            response = self._send_operation(operation)
            if response.get('status') == 'success':
                # Update tensor registry
                with self.lock:
                    self.tensor_registry[tensor_id] = {
                        'shape': tensor_shape,
                        'dtype': tensor_dtype,
                        'size': tensor_size,
                        'timestamp': time.time()
                    }
                    self.resource_monitor['vram_used'] += tensor_size
                    self.resource_monitor['active_tensors'] += 1
                return True
            else:
                print(f"Failed to store tensor {tensor_id}: {response.get('message', 'Unknown error')}")
                return False
        except Exception as e:
            print(f"Error storing tensor {tensor_id}: {str(e)}")
            return False

    def load_tensor(self, tensor_id: str) -> Optional[np.ndarray]:
        try:
            # Check tensor registry first
            if tensor_id not in self.tensor_registry:
                print(f"Tensor {tensor_id} not registered in VRAM")
                return None
                
            operation = {
                'operation': 'vram',
                'type': 'read',
                'block_id': tensor_id,
                'expected_metadata': self.tensor_registry.get(tensor_id, {})
            }
            
            response = self._send_operation(operation)
            if response.get('status') == 'success':
                data = response.get('data')
                if data is None:
                    print(f"No data found for tensor {tensor_id}")
                    return None
                    
                # Verify tensor metadata
                metadata = response.get('metadata', {})
                expected_metadata = self.tensor_registry.get(tensor_id, {})
                if metadata.get('shape') != expected_metadata.get('shape'):
                    print(f"Warning: Tensor {tensor_id} shape mismatch")
                    
                try:
                    # Convert to numpy array with correct dtype
                    arr = np.array(data, dtype=np.dtype(expected_metadata.get('dtype', 'float32')))
                    if arr.shape != expected_metadata.get('shape'):
                        arr = arr.reshape(expected_metadata.get('shape'))
                    return arr
                except Exception as e:
                    print(f"Error converting tensor data: {str(e)}")
                    return None
            else:
                print(f"Failed to load tensor {tensor_id}: {response.get('message', 'Unknown error')}")
                return None
        except Exception as e:
            print(f"Error loading tensor {tensor_id}: {str(e)}")
            return None

    def store_state(self, component: str, state_id: str, state_data: Dict[str, Any]) -> bool:
        try:
            operation = {
                'operation': 'state',
                'type': 'save',
                'component': component,
                'state_id': state_id,
                'data': state_data,
                'timestamp': time.time()
            }
            
            response = self._send_operation(operation)
            if response.get('status') != 'success':
                print(f"Failed to store state for {component}/{state_id}: {response.get('message', 'Unknown error')}")
                return False
            return True
        except Exception as e:
            print(f"Error storing state for {component}/{state_id}: {str(e)}")
            return False

    def load_state(self, component: str, state_id: str) -> Optional[Dict[str, Any]]:
        try:
            operation = {
                'operation': 'state',
                'type': 'load',
                'component': component,
                'state_id': state_id
            }
            
            response = self._send_operation(operation)
            if response.get('status') == 'success':
                data = response.get('data')
                if data is None:
                    print(f"No state found for {component}/{state_id}")
                    return None
                return data
            else:
                print(f"Failed to load state for {component}/{state_id}: {response.get('message', 'Unknown error')}")
                return None
        except Exception as e:
            print(f"Error loading state for {component}/{state_id}: {str(e)}")
            return None

    def is_model_loaded(self, model_name: str) -> bool:
        """Check if a model is already loaded in VRAM"""
        return model_name in self.resource_monitor['loaded_models']

    def load_model(self, model_name: str, model_path: Optional[str] = None, model_data: Optional[Dict] = None) -> bool:
        """Load a model into VRAM if not already loaded"""
        try:
            # Check if model is already loaded
            if self.is_model_loaded(model_name):
                print(f"Model {model_name} already loaded in VRAM")
                return True

            # Calculate model hash if path provided
            model_hash = None
            if model_path:
                model_hash = self._calculate_model_hash(model_path)

            operation = {
                'operation': 'model',
                'type': 'load',
                'model_name': model_name,
                'model_hash': model_hash,
                'model_data': model_data
            }

            response = self._send_operation(operation)
            if response.get('status') == 'success':
                with self.lock:
                    self.model_registry[model_name] = {
                        'hash': model_hash,
                        'timestamp': time.time(),
                        'tensors': response.get('tensor_ids', [])
                    }
                    self.resource_monitor['loaded_models'].add(model_name)
                print(f"Successfully loaded model {model_name}")
                return True
            else:
                print(f"Failed to load model {model_name}: {response.get('message', 'Unknown error')}")
                return False
        except Exception as e:
            print(f"Error loading model {model_name}: {str(e)}")
            return False

    def _calculate_model_hash(self, model_path: str) -> str:
        """Calculate SHA256 hash of model file"""
        try:
            sha256_hash = hashlib.sha256()
            with open(model_path, "rb") as f:
                for byte_block in iter(lambda: f.read(4096), b""):
                    sha256_hash.update(byte_block)
            return sha256_hash.hexdigest()
        except Exception as e:
            print(f"Error calculating model hash: {str(e)}")
            return ""

    def cache_data(self, key: str, data: Any) -> bool:
        operation = {
            'operation': 'cache',
            'type': 'set',
            'key': key,
            'data': data
        }
        
        response = self._send_operation(operation)
        return response.get('status') == 'success'

    def get_cached_data(self, key: str) -> Optional[Any]:
        operation = {
            'operation': 'cache',
            'type': 'get',
            'key': key
        }
        
        response = self._send_operation(operation)
        if response.get('status') == 'success':
            return response['data']
        return None

    def wait_for_connection(self, timeout: float = 30.0) -> bool:
        """Wait for WebSocket connection to be established"""
        start_time = time.time()
        while not self._closing and not self.connected:
            if time.time() - start_time > timeout:
                print("Connection timeout exceeded")
                return False
            time.sleep(0.1)
        return self.connected

    def is_connected(self) -> bool:
        """Check if WebSocket connection is active"""
        return self.connected and not self._closing
        
    def get_connection_status(self) -> Dict[str, Any]:
        """Get detailed connection status"""
        return {
            "connected": self.connected,
            "closing": self._closing,
            "error_count": self.error_count,
            "url": self.url,
            "last_error_time": self.last_error_time,
            "loaded_models": list(self.resource_monitor['loaded_models'])
        }
        
    def start_inference(self, model_name: str, input_data: np.ndarray) -> Optional[Dict[str, Any]]:
        """Start inference with a loaded model"""
        try:
            if not self.is_model_loaded(model_name):
                print(f"Model {model_name} not loaded. Please load the model first.")
                return None
                
            operation = {
                'operation': 'inference',
                'type': 'run',
                'model_name': model_name,
                'input_data': input_data.tolist() if isinstance(input_data, np.ndarray) else input_data
            }
            
            response = self._send_operation(operation)
            if response.get('status') == 'success':
                return {
                    'output': np.array(response['output']) if 'output' in response else None,
                    'metrics': response.get('metrics', {}),
                    'model_info': self.model_registry.get(model_name, {})
                }
            else:
                print(f"Inference failed: {response.get('message', 'Unknown error')}")
                return None
        except Exception as e:
            print(f"Error during inference: {str(e)}")
            return None

    def close(self):
        """Close WebSocket connection and cleanup resources."""
        if not self._closing:
            self._closing = True
            if self.websocket and self._loop:
                async def cleanup():
                    try:
                        # Clean up registries
                        with self.lock:
                            self.tensor_registry.clear()
                            self.model_registry.clear()
                            self.resource_monitor['vram_used'] = 0
                            self.resource_monitor['active_tensors'] = 0
                            self.resource_monitor['loaded_models'].clear()
                        
                        # Notify server about cleanup
                        if self.connected:
                            try:
                                await self.websocket.send(json.dumps({
                                    'operation': 'cleanup',
                                    'type': 'full'
                                }))
                            except:
                                pass
                                
                        await self.websocket.close()
                    except Exception as e:
                        print(f"Error during cleanup: {str(e)}")
                    finally:
                        self.connected = False
                        
                if self._loop.is_running():
                    self._loop.create_task(cleanup())
                else:
                    asyncio.run(cleanup())

    async def aclose(self):
        """Asynchronously close WebSocket connection."""
        if not self._closing:
            self._closing = True
            if self.websocket:
                try:
                    await self.websocket.close()
                except:
                    pass
                finally:
                    self.connected = False
                    
    def __del__(self):
        """Ensure cleanup on deletion."""
        self.close()