Pac-cogs/videoarchiver/queue/manager.py

"""Enhanced queue manager for video processing"""

import asyncio
import logging
import time
from typing import Dict, Optional, Set, Tuple, Callable, Any, List
from datetime import datetime

from .models import QueueItem, QueueMetrics
from .persistence import QueuePersistenceManager, QueueError
from .monitoring import QueueMonitor, MonitoringError
from .cleanup import QueueCleaner, CleanupError

# Configure logging
logging.basicConfig(
    level=logging.INFO, format="%(asctime)s - %(name)s - %(levelname)s - %(message)s"
)
logger = logging.getLogger("QueueManager")

class EnhancedVideoQueueManager:
    """Enhanced queue manager with improved memory management and performance"""

    def __init__(
        self,
        max_retries: int = 3,
        retry_delay: int = 5,
        max_queue_size: int = 1000,
        cleanup_interval: int = 3600,  # 1 hour
        max_history_age: int = 86400,  # 24 hours
        persistence_path: Optional[str] = None,
        backup_interval: int = 300,  # 5 minutes
        deadlock_threshold: int = 300,  # 5 minutes
        check_interval: int = 60,     # 1 minute
    ):
        # Configuration
        self.max_retries = max_retries
        self.retry_delay = retry_delay
        self.max_queue_size = max_queue_size
        
        # Queue storage
        self._queue: List[QueueItem] = []
        self._processing: Dict[str, QueueItem] = {}
        self._completed: Dict[str, QueueItem] = {}
        self._failed: Dict[str, QueueItem] = {}

        # Tracking
        self._guild_queues: Dict[int, Set[str]] = {}
        self._channel_queues: Dict[int, Set[str]] = {}
        self._active_tasks: Set[asyncio.Task] = set()
        
        # Locks
        self._queue_lock = asyncio.Lock()
        self._processing_lock = asyncio.Lock()
        
        # State
        self._shutdown = False
        self.metrics = QueueMetrics()

        # Components
        self.persistence = QueuePersistenceManager(persistence_path) if persistence_path else None
        self.monitor = QueueMonitor(
            deadlock_threshold=deadlock_threshold,
            max_retries=max_retries,
            check_interval=check_interval
        )
        self.cleaner = QueueCleaner(
            cleanup_interval=cleanup_interval,
            max_history_age=max_history_age
        )

        # Initialize tasks
        self._init_tasks()

    def _init_tasks(self) -> None:
        """Initialize background tasks"""
        # Start monitoring
        monitor_task = asyncio.create_task(
            self.monitor.start_monitoring(
                self._queue,
                self._processing,
                self.metrics,
                self._processing_lock
            )
        )
        self._active_tasks.add(monitor_task)
        logger.info("Queue monitoring started")

        # Start cleanup
        cleanup_task = asyncio.create_task(
            self.cleaner.start_cleanup(
                self._queue,
                self._completed,
                self._failed,
                self._guild_queues,
                self._channel_queues,
                self._processing,
                self.metrics,
                self._queue_lock
            )
        )
        self._active_tasks.add(cleanup_task)
        logger.info("Queue cleanup started")

        # Load persisted state if available
        if self.persistence:
            self._load_persisted_state()

    def _load_persisted_state(self) -> None:
        """Load persisted queue state"""
        try:
            state = self.persistence.load_queue_state()
            if state:
                self._queue = state["queue"]
                self._processing = state["processing"]
                self._completed = state["completed"]
                self._failed = state["failed"]

                # Update metrics
                metrics_data = state.get("metrics", {})
                self.metrics.total_processed = metrics_data.get("total_processed", 0)
                self.metrics.total_failed = metrics_data.get("total_failed", 0)
                self.metrics.avg_processing_time = metrics_data.get("avg_processing_time", 0.0)
                self.metrics.success_rate = metrics_data.get("success_rate", 0.0)
                self.metrics.errors_by_type = metrics_data.get("errors_by_type", {})
                self.metrics.compression_failures = metrics_data.get("compression_failures", 0)
                self.metrics.hardware_accel_failures = metrics_data.get("hardware_accel_failures", 0)

                logger.info("Loaded persisted queue state")
        except Exception as e:
            logger.error(f"Failed to load persisted state: {e}")

    async def process_queue(
        self,
        processor: Callable[[QueueItem], Tuple[bool, Optional[str]]]
    ) -> None:
        """Process items in the queue
        
        Args:
            processor: Function that processes queue items
        """
        logger.info("Queue processor started")
        last_persist_time = time.time()
        persist_interval = 60  # Persist state every 60 seconds instead of every operation
        
        while not self._shutdown:
            try:
                # Process items in batches to avoid blocking
                async with self._queue_lock:
                    # Get up to 5 items from queue
                    items = []
                    while len(items) < 5 and self._queue:
                        item = self._queue.pop(0)
                        self._processing[item.url] = item
                        items.append(item)

                if not items:
                    # Use shorter sleep when queue is empty and yield control
                    await asyncio.sleep(0.1)
                    continue

                # Process items concurrently
                tasks = []
                for item in items:
                    task = asyncio.create_task(self._process_item(processor, item))
                    tasks.append(task)
                
                # Wait for all tasks to complete
                await asyncio.gather(*tasks, return_exceptions=True)

                # Persist state if interval has passed
                current_time = time.time()
                if self.persistence and (current_time - last_persist_time) >= persist_interval:
                    await self.persistence.persist_queue_state(
                        self._queue,
                        self._processing,
                        self._completed,
                        self._failed,
                        self.metrics
                    )
                    last_persist_time = current_time

            except Exception as e:
                logger.error(f"Critical error in queue processor: {e}")
                await asyncio.sleep(0.1)  # Brief pause on error before retrying

            # Yield control after each batch
            await asyncio.sleep(0)

        logger.info("Queue processor stopped")

    async def _process_item(
        self,
        processor: Callable[[QueueItem], Tuple[bool, Optional[str]]],
        item: QueueItem
    ) -> None:
        """Process a single queue item"""
        try:
            # Process the item
            logger.info(f"Processing queue item: {item.url}")
            item.start_processing()  # Start processing tracking
            self.metrics.last_activity_time = time.time()  # Update activity time
            
            success, error = await processor(item)
            
            # Update metrics and status
            async with self._processing_lock:
                item.finish_processing(success, error)  # Update item status
                
                if success:
                    self._completed[item.url] = item
                    logger.info(f"Successfully processed: {item.url}")
                else:
                    if item.retry_count < self.max_retries:
                        item.retry_count += 1
                        item.status = "pending"
                        item.last_retry = datetime.utcnow()
                        item.priority = max(0, item.priority - 1)
                        self._queue.append(item)
                        logger.warning(f"Retrying: {item.url} (attempt {item.retry_count})")
                    else:
                        self._failed[item.url] = item
                        logger.error(f"Failed after {self.max_retries} attempts: {item.url}")

                self._processing.pop(item.url, None)
                
                # Update metrics
                self.metrics.update(
                    processing_time=item.processing_time,
                    success=success,
                    error=error
                )

        except Exception as e:
            logger.error(f"Error processing {item.url}: {e}")
            async with self._processing_lock:
                item.finish_processing(False, str(e))
                self._failed[item.url] = item
                self._processing.pop(item.url, None)
                self.metrics.update(
                    processing_time=item.processing_time,
                    success=False,
                    error=str(e)
                )

    async def add_to_queue(
        self,
        url: str,
        message_id: int,
        channel_id: int,
        guild_id: int,
        author_id: int,
        priority: int = 0,
    ) -> bool:
        """Add a video to the processing queue"""
        if self._shutdown:
            raise QueueError("Queue manager is shutting down")

        try:
            async with self._queue_lock:
                if len(self._queue) >= self.max_queue_size:
                    raise QueueError("Queue is full")

                item = QueueItem(
                    url=url,
                    message_id=message_id,
                    channel_id=channel_id,
                    guild_id=guild_id,
                    author_id=author_id,
                    added_at=datetime.utcnow(),
                    priority=priority,
                )

                # Add to tracking
                if guild_id not in self._guild_queues:
                    self._guild_queues[guild_id] = set()
                self._guild_queues[guild_id].add(url)

                if channel_id not in self._channel_queues:
                    self._channel_queues[channel_id] = set()
                self._channel_queues[channel_id].add(url)

                # Add to queue with priority
                self._queue.append(item)
                self._queue.sort(key=lambda x: (-x.priority, x.added_at))

                # Update activity time
                self.metrics.last_activity_time = time.time()

                if self.persistence:
                    await self.persistence.persist_queue_state(
                        self._queue,
                        self._processing,
                        self._completed,
                        self._failed,
                        self.metrics
                    )

                logger.info(f"Added to queue: {url} (priority: {priority})")
                return True

        except Exception as e:
            logger.error(f"Error adding to queue: {e}")
            raise QueueError(f"Failed to add to queue: {str(e)}")

    def get_queue_status(self, guild_id: int) -> dict:
        """Get current queue status for a guild"""
        try:
            pending = len([item for item in self._queue if item.guild_id == guild_id])
            processing = len([item for item in self._processing.values() if item.guild_id == guild_id])
            completed = len([item for item in self._completed.values() if item.guild_id == guild_id])
            failed = len([item for item in self._failed.values() if item.guild_id == guild_id])

            return {
                "pending": pending,
                "processing": processing,
                "completed": completed,
                "failed": failed,
                "metrics": {
                    "total_processed": self.metrics.total_processed,
                    "total_failed": self.metrics.total_failed,
                    "success_rate": self.metrics.success_rate,
                    "avg_processing_time": self.metrics.avg_processing_time,
                    "peak_memory_usage": self.metrics.peak_memory_usage,
                    "last_cleanup": self.metrics.last_cleanup.strftime("%Y-%m-%d %H:%M:%S"),
                    "errors_by_type": self.metrics.errors_by_type,
                    "compression_failures": self.metrics.compression_failures,
                    "hardware_accel_failures": self.metrics.hardware_accel_failures,
                    "last_activity": time.time() - self.metrics.last_activity_time,
                },
            }

        except Exception as e:
            logger.error(f"Error getting queue status: {e}")
            return {
                "pending": 0,
                "processing": 0,
                "completed": 0,
                "failed": 0,
                "metrics": {
                    "total_processed": 0,
                    "total_failed": 0,
                    "success_rate": 0.0,
                    "avg_processing_time": 0.0,
                    "peak_memory_usage": 0.0,
                    "last_cleanup": datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S"),
                    "errors_by_type": {},
                    "compression_failures": 0,
                    "hardware_accel_failures": 0,
                    "last_activity": 0,
                },
            }

    async def clear_guild_queue(self, guild_id: int) -> int:
        """Clear all queue items for a guild"""
        if self._shutdown:
            raise QueueError("Queue manager is shutting down")

        try:
            cleared = await self.cleaner.clear_guild_queue(
                guild_id,
                self._queue,
                self._processing,
                self._completed,
                self._failed,
                self._guild_queues,
                self._channel_queues,
                self._queue_lock
            )

            if self.persistence:
                await self.persistence.persist_queue_state(
                    self._queue,
                    self._processing,
                    self._completed,
                    self._failed,
                    self.metrics
                )

            return cleared

        except Exception as e:
            logger.error(f"Error clearing guild queue: {e}")
            raise QueueError(f"Failed to clear guild queue: {str(e)}")

    async def cleanup(self) -> None:
        """Clean up resources and stop queue processing"""
        try:
            self._shutdown = True
            logger.info("Starting queue manager cleanup...")
            
            # Stop monitoring and cleanup tasks
            self.monitor.stop_monitoring()
            self.cleaner.stop_cleanup()

            # Cancel all active tasks
            for task in self._active_tasks:
                if not task.done():
                    task.cancel()

            await asyncio.gather(*self._active_tasks, return_exceptions=True)

            # Move processing items back to queue
            async with self._queue_lock:
                for url, item in self._processing.items():
                    if item.retry_count < self.max_retries:
                        item.status = "pending"
                        item.retry_count += 1
                        self._queue.append(item)
                    else:
                        self._failed[url] = item

                self._processing.clear()

            # Final state persistence
            if self.persistence:
                await self.persistence.persist_queue_state(
                    self._queue,
                    self._processing,
                    self._completed,
                    self._failed,
                    self.metrics
                )

            # Clear collections
            self._queue.clear()
            self._completed.clear()
            self._failed.clear()
            self._guild_queues.clear()
            self._channel_queues.clear()
            self._active_tasks.clear()

            logger.info("Queue manager cleanup completed")

        except Exception as e:
            logger.error(f"Error during cleanup: {e}")
            raise CleanupError(f"Failed to clean up queue manager: {str(e)}")

    def force_stop(self) -> None:
        """Force stop all queue operations immediately"""
        self._shutdown = True
        logger.info("Force stopping queue manager...")
        
        # Stop monitoring and cleanup
        self.monitor.stop_monitoring()
        self.cleaner.stop_cleanup()
        
        # Cancel all active tasks
        for task in self._active_tasks:
            if not task.done():
                task.cancel()

        # Move processing items back to queue
        for url, item in self._processing.items():
            if item.retry_count < self.max_retries:
                item.status = "pending"
                item.retry_count += 1
                self._queue.append(item)
            else:
                self._failed[url] = item

        self._processing.clear()
        self._active_tasks.clear()

        logger.info("Queue manager force stopped")