"""
Virtual GPU Driver Module

This module provides the interface between the simulated CPU and the virtual GPU.
It handles command queues, data transfers, and status management for CPU-GPU communication.
"""

import asyncio
import queue
import threading
import time
from typing import Dict, Any, Optional, List
from dataclasses import dataclass
from enum import Enum

# Import virtual GPU components
from virtual_gpu.vgpu import VirtualGPU, TaskType, Task
from virtual_gpu.vram import VRAM


class GPUCommandType(Enum):
    """Types of commands that can be sent to the GPU."""
    RENDER_CLEAR = "render_clear"
    RENDER_RECT = "render_rect"
    RENDER_IMAGE = "render_image"
    AI_INFERENCE = "ai_inference"
    AI_MATRIX_MULTIPLY = "ai_matrix_multiply"
    AI_VECTOR_OP = "ai_vector_op"
    DATA_TRANSFER = "data_transfer"
    MEMORY_ALLOC = "memory_alloc"
    MEMORY_FREE = "memory_free"


@dataclass
class GPUCommand:
    """Represents a command to be executed by the GPU."""
    command_id: str
    command_type: GPUCommandType
    payload: Dict[str, Any]
    cpu_core_id: int
    status: str = "pending"
    result: Optional[Any] = None
    created_time: float = 0.0
    completed_time: float = 0.0


class VirtualGPUDriver:
    """
    Virtual GPU Driver that provides the interface between CPU and GPU.
    
    This driver manages command queues, data transfers, and status tracking
    for CPU-GPU communication in the integrated virtual hardware system.
    """
    
    def __init__(self, vgpu: VirtualGPU, vram: VRAM):
        self.vgpu = vgpu
        self.vram = vram
        
        # Command management
        self.command_queue = queue.Queue()
        self.completed_commands = {}
        self.command_counter = 0
        
        # Status tracking
        self.is_running = False
        self.driver_thread = None
        
        # Statistics
        self.total_commands_processed = 0
        self.total_data_transferred = 0
        
    def start_driver(self):
        """Start the GPU driver in a separate thread."""
        if not self.is_running:
            self.is_running = True
            self.driver_thread = threading.Thread(target=self._driver_loop, daemon=True)
            self.driver_thread.start()
            print("Virtual GPU Driver started")
            
    def stop_driver(self):
        """Stop the GPU driver."""
        self.is_running = False
        if self.driver_thread:
            self.driver_thread.join(timeout=1.0)
        print("Virtual GPU Driver stopped")
        
    def submit_command(self, command_type: GPUCommandType, payload: Dict[str, Any], 
                      cpu_core_id: int = 0) -> str:
        """Submit a command to the GPU and return command ID."""
        command_id = f"gpu_cmd_{self.command_counter}"
        self.command_counter += 1
        
        command = GPUCommand(
            command_id=command_id,
            command_type=command_type,
            payload=payload,
            cpu_core_id=cpu_core_id,
            created_time=time.time()
        )
        
        self.command_queue.put(command)
        return command_id
        
    def get_command_status(self, command_id: str) -> Optional[str]:
        """Get the status of a command."""
        if command_id in self.completed_commands:
            return self.completed_commands[command_id].status
        return "pending"
        
    def get_command_result(self, command_id: str) -> Optional[Any]:
        """Get the result of a completed command."""
        if command_id in self.completed_commands:
            command = self.completed_commands[command_id]
            if command.status == "completed":
                return command.result
        return None
        
    def wait_for_command(self, command_id: str, timeout: float = 10.0) -> bool:
        """Wait for a command to complete."""
        start_time = time.time()
        while time.time() - start_time < timeout:
            if command_id in self.completed_commands:
                return self.completed_commands[command_id].status == "completed"
            time.sleep(0.01)
        return False
        
    def transfer_data_to_vram(self, data: Any, name: str, delay_ms: float = 0.0) -> Optional[str]:
        """Transfer data from CPU RAM to VRAM."""
        try:
            texture_id = self.vram.transfer_from_ram(name, data, delay_ms)
            if texture_id:
                self.total_data_transferred += len(data) if hasattr(data, '__len__') else 0
            return texture_id
        except Exception as e:
            print(f"Error transferring data to VRAM: {e}")
            return None
            
    def create_framebuffer(self, width: int, height: int, channels: int = 3, 
                          name: Optional[str] = None) -> Optional[str]:
        """Create a framebuffer in VRAM."""
        try:
            return self.vram.create_framebuffer(width, height, channels, name)
        except Exception as e:
            print(f"Error creating framebuffer: {e}")
            return None
            
    def _driver_loop(self):
        """Main driver loop that processes commands."""
        while self.is_running:
            try:
                # Process commands from the queue
                try:
                    command = self.command_queue.get_nowait()
                    self._process_command(command)
                except queue.Empty:
                    pass
                    
                # Small delay to prevent busy waiting
                time.sleep(0.001)
                
            except Exception as e:
                print(f"Error in GPU driver loop: {e}")
                
    def _process_command(self, command: GPUCommand):
        """Process a single GPU command."""
        try:
            command.status = "processing"
            
            if command.command_type == GPUCommandType.RENDER_CLEAR:
                # Submit clear task to vGPU
                task_id = self.vgpu.submit_task(TaskType.RENDER_CLEAR, command.payload)
                command.result = {"task_id": task_id}
                
            elif command.command_type == GPUCommandType.RENDER_RECT:
                # Submit rectangle rendering task to vGPU
                task_id = self.vgpu.submit_task(TaskType.RENDER_RECT, command.payload)
                command.result = {"task_id": task_id}
                
            elif command.command_type == GPUCommandType.RENDER_IMAGE:
                # Submit image rendering task to vGPU
                task_id = self.vgpu.submit_task(TaskType.RENDER_IMAGE, command.payload)
                command.result = {"task_id": task_id}
                
            elif command.command_type == GPUCommandType.AI_MATRIX_MULTIPLY:
                # Submit matrix multiplication task to vGPU
                task_id = self.vgpu.submit_task(TaskType.AI_MATRIX_MULTIPLY, command.payload)
                command.result = {"task_id": task_id}
                
            elif command.command_type == GPUCommandType.AI_VECTOR_OP:
                # Submit vector operation task to vGPU
                task_id = self.vgpu.submit_task(TaskType.AI_VECTOR_OP, command.payload)
                command.result = {"task_id": task_id}
                
            elif command.command_type == GPUCommandType.DATA_TRANSFER:
                # Handle data transfer to VRAM
                data = command.payload.get("data")
                name = command.payload.get("name", f"transfer_{command.command_id}")
                delay_ms = command.payload.get("delay_ms", 0.0)
                
                texture_id = self.transfer_data_to_vram(data, name, delay_ms)
                command.result = {"texture_id": texture_id}
                
            elif command.command_type == GPUCommandType.MEMORY_ALLOC:
                # Create framebuffer or allocate memory
                width = command.payload.get("width", 1920)
                height = command.payload.get("height", 1080)
                channels = command.payload.get("channels", 3)
                name = command.payload.get("name")
                
                fb_id = self.create_framebuffer(width, height, channels, name)
                command.result = {"framebuffer_id": fb_id}
                
            elif command.command_type == GPUCommandType.MEMORY_FREE:
                # Free framebuffer or memory
                name = command.payload.get("name")
                success = self.vram.delete_framebuffer(name)
                command.result = {"success": success}
                
            else:
                command.status = "error"
                command.result = {"error": f"Unknown command type: {command.command_type}"}
                
            if command.status != "error":
                command.status = "completed"
                
            command.completed_time = time.time()
            self.completed_commands[command.command_id] = command
            self.total_commands_processed += 1
            
        except Exception as e:
            command.status = "error"
            command.result = {"error": str(e)}
            command.completed_time = time.time()
            self.completed_commands[command.command_id] = command
            print(f"Error processing GPU command {command.command_id}: {e}")
            
    def get_driver_stats(self) -> Dict[str, Any]:
        """Get driver statistics."""
        vgpu_stats = self.vgpu.get_stats()
        vram_stats = self.vram.get_stats()
        
        return {
            "driver_status": "running" if self.is_running else "stopped",
            "total_commands_processed": self.total_commands_processed,
            "total_data_transferred": self.total_data_transferred,
            "pending_commands": self.command_queue.qsize(),
            "completed_commands": len(self.completed_commands),
            "vgpu_stats": vgpu_stats,
            "vram_stats": vram_stats
        }


# CPU Extensions for GPU Communication
class CPUGPUInterface:
    """
    Interface for CPU cores to communicate with the GPU driver.
    
    This class provides high-level methods that CPU cores can use to
    interact with the virtual GPU without dealing with low-level details.
    """
    
    def __init__(self, gpu_driver: VirtualGPUDriver):
        self.gpu_driver = gpu_driver
        
    def gpu_clear_screen(self, color: tuple = (0, 0, 0), core_id: int = 0) -> str:
        """Clear the screen with the specified color."""
        payload = {"color": color}
        return self.gpu_driver.submit_command(GPUCommandType.RENDER_CLEAR, payload, core_id)
        
    def gpu_draw_rect(self, x: int, y: int, width: int, height: int, 
                     color: tuple = (255, 255, 255), core_id: int = 0) -> str:
        """Draw a rectangle on the screen."""
        payload = {
            "x": x, "y": y, "width": width, "height": height, "color": color
        }
        return self.gpu_driver.submit_command(GPUCommandType.RENDER_RECT, payload, core_id)
        
    def gpu_ai_inference(self, model_data: Any, input_data: Any, core_id: int = 0) -> str:
        """Perform AI inference using the GPU."""
        payload = {"model_data": model_data, "input_data": input_data}
        return self.gpu_driver.submit_command(GPUCommandType.AI_INFERENCE, payload, core_id)
        
    def gpu_matrix_multiply(self, matrix_a: Any, matrix_b: Any, core_id: int = 0) -> str:
        """Perform matrix multiplication on the GPU."""
        payload = {"matrix_a": matrix_a, "matrix_b": matrix_b}
        return self.gpu_driver.submit_command(GPUCommandType.AI_MATRIX_MULTIPLY, payload, core_id)
        
    def gpu_transfer_data(self, data: Any, name: str, core_id: int = 0) -> str:
        """Transfer data to GPU VRAM."""
        payload = {"data": data, "name": name}
        return self.gpu_driver.submit_command(GPUCommandType.DATA_TRANSFER, payload, core_id)
        
    def gpu_alloc_framebuffer(self, width: int, height: int, channels: int = 3, 
                             name: Optional[str] = None, core_id: int = 0) -> str:
        """Allocate a framebuffer in GPU VRAM."""
        payload = {"width": width, "height": height, "channels": channels, "name": name}
        return self.gpu_driver.submit_command(GPUCommandType.MEMORY_ALLOC, payload, core_id)
        
    def wait_for_gpu_task(self, command_id: str, timeout: float = 10.0) -> bool:
        """Wait for a GPU task to complete."""
        return self.gpu_driver.wait_for_command(command_id, timeout)
        
    def get_gpu_result(self, command_id: str) -> Optional[Any]:
        """Get the result of a completed GPU task."""
        return self.gpu_driver.get_command_result(command_id)


if __name__ == "__main__":
    # Test the GPU driver
    from virtual_gpu.vgpu import VirtualGPU
    from virtual_gpu.vram import VRAM
    
    # Create virtual GPU and VRAM
    vgpu = VirtualGPU(num_sms=800, total_cores=50000)
    vram = VRAM(memory_size_gb=500)
    
    # Create and start the driver
    driver = VirtualGPUDriver(vgpu, vram)
    driver.start_driver()
    
    # Create CPU-GPU interface
    cpu_gpu = CPUGPUInterface(driver)
    
    # Test some operations
    print("Testing GPU driver...")
    
    # Clear screen
    cmd_id = cpu_gpu.gpu_clear_screen((255, 0, 0))
    print(f"Clear screen command: {cmd_id}")
    
    # Draw rectangle
    cmd_id = cpu_gpu.gpu_draw_rect(100, 100, 200, 150, (0, 255, 0))
    print(f"Draw rectangle command: {cmd_id}")
    
    # Transfer some data
    test_data = b"Hello GPU!"
    cmd_id = cpu_gpu.gpu_transfer_data(test_data, "test_data")
    print(f"Data transfer command: {cmd_id}")
    
    # Wait a bit and check stats
    time.sleep(1)
    stats = driver.get_driver_stats()
    print(f"Driver stats: {stats}")
    
    # Stop the driver
    driver.stop_driver()
    print("GPU driver test completed")