dmsc/device/

pool.rs

//! Copyright © 2025-2026 Wenze Wei. All Rights Reserved.
//!
//! This file is part of DMSC.
//! The DMSC project belongs to the Dunimd Team.
//!
//! Licensed under the Apache License, Version 2.0 (the "License");
//! You may not use this file except in compliance with the License.
//! You may obtain a copy of the License at
//!
//!     http://www.apache.org/licenses/LICENSE-2.0
//!
//! Unless required by applicable law or agreed to in writing, software
//! distributed under the License is distributed on an "AS IS" BASIS,
//! WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//! See the License for the specific language governing permissions and
//! limitations under the License.

#![allow(non_snake_case)]

//! # Resource Pool Management
//! 
//! This file implements resource pool management for the DMSC framework, providing a way to group
//! similar devices together for efficient resource allocation and management. It includes both
//! single resource pools and a resource pool manager for handling multiple pools.
//! 
//! ## Key Components
//! 
//! - **DMSCResourcePool**: Manages a pool of similar devices
//! - **DMSCResourcePoolConfig**: Configuration for resource pools
//! - **DMSCResourcePoolStatistics**: Statistics for monitoring resource pools
//! - **DMSCResourcePoolManager**: Manages multiple resource pools
//! 
//! ## Design Principles
//! 
//! 1. **Resource Grouping**: Groups similar devices together for efficient management
//! 2. **Capacity Tracking**: Tracks total, available, and allocated capacity
//! 3. **Statistics Collection**: Collects comprehensive statistics for monitoring
//! 4. **Device Filtering**: Filters devices by availability and allocation status
//! 5. **Health Monitoring**: Monitors pool health based on available devices
//! 6. **Utilization Tracking**: Tracks resource utilization rates
//! 7. **Multi-Pool Management**: Supports managing multiple pools through a central manager
//! 8. **Device Type Segregation**: Each pool contains devices of a single type
//! 9. **Arc-Based Sharing**: Uses Arc for safe concurrent access to devices
//! 10. **Serialization Support**: All structures support serialization/deserialization
//! 11. **Builder Pattern**: Configurable through DMSCResourcePoolConfig
//! 12. **Resource Optimization**: Calculates total compute, memory, storage, and bandwidth
//! 
//! ## Usage
//! 
//! ```rust,ignore
//! use dmsc::device::{DMSCResourcePoolManager, DMSCResourcePoolConfig, DMSCDeviceType};
//! use dmsc::core::DMSCResult;
//! 
//! fn example() -> DMSCResult<()> {
//!     // Create a resource pool manager
//!     let mut manager = DMSCResourcePoolManager::new();
//!     
//!     // Create a resource pool configuration
//!     let config = DMSCResourcePoolConfig {
//!         name: "cpu-pool-1".to_string(),
//!         device_type: DMSCDeviceType::CPU,
//!         max_concurrent_allocations: 10,
//!         allocation_timeout_secs: 60,
//!         health_check_interval_secs: 30,
//!     };
//!     
//!     // Create a resource pool
//!     let pool = manager.create_pool(config);
//!     
//!     // Get pool statistics
//!     let stats = pool.get_statistics();
//!     println!("Pool has {} devices, utilization: {:.2}%", 
//!              stats.total_devices, stats.utilization_rate * 100.0);
//!     
//!     // Get all pools by device type
//!     let cpu_pools = manager.get_pools_by_type(DMSCDeviceType::CPU);
//!     println!("Found {} CPU pools", cpu_pools.len());
//!     
//!     // Get overall statistics
//!     let overall_stats = manager.get_overall_statistics();
//!     println!("Total devices across all pools: {}", overall_stats.total_devices);
//!     
//!     Ok(())
//! }
//! ```

use std::sync::{Arc, RwLock};
use std::collections::HashMap;
use std::time::Duration;
use serde::{Serialize, Deserialize};

use super::core::{DMSCDevice, DMSCDeviceType, DMSCDeviceStatus};


/// Resource pool for managing multiple similar devices
/// 
/// This struct manages a pool of devices of the same type, tracking their availability,
/// allocation status, and capacity. It provides methods for adding/removing devices,
/// allocating/releasing devices, and collecting statistics.
#[cfg_attr(feature = "pyo3", pyo3::prelude::pyclass)]
pub struct DMSCResourcePool {
    /// Name of the resource pool
    name: String,
    /// Type of devices in the pool
    device_type: DMSCDeviceType,
    /// Map of device IDs to device instances
    devices: HashMap<String, Arc<DMSCDevice>>,
    /// Total capacity of the pool (number of devices)
    total_capacity: usize,
    /// Available capacity (number of devices not allocated)
    available_capacity: usize,
    /// Allocated capacity (number of devices currently allocated)
    allocated_capacity: usize,
    /// Number of pending requests for devices
    pending_requests: usize,
    /// Total compute units across all devices in the pool
    total_compute_units: usize,
    /// Total memory in GB across all devices in the pool
    total_memory_gb: f64,
    /// Total storage in GB across all devices in the pool
    total_storage_gb: f64,
    /// Total bandwidth in Gbps across all devices in the pool
    total_bandwidth_gbps: f64,
    /// Available compute units (not allocated)
    available_compute_units: usize,
    /// Available memory in GB (not allocated)
    available_memory_gb: f64,
    /// Available storage in GB (not allocated)
    available_storage_gb: f64,
    /// Available bandwidth in Gbps (not allocated)
    available_bandwidth_gbps: f64,
    /// Connection pool state for lifecycle management
    connection_pool: Arc<RwLock<DMSCConnectionPool>>,
}

/// Configuration for a resource pool
/// 
/// This struct defines the configuration options for creating a resource pool, including
/// name, device type, and various operational parameters.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[cfg_attr(feature = "pyo3", pyo3::prelude::pyclass(get_all, set_all))]
pub struct DMSCResourcePoolConfig {
    /// Name of the resource pool
    pub name: String,
    /// Type of devices that will be in the pool
    pub device_type: DMSCDeviceType,
    /// Maximum number of concurrent allocations allowed
    pub max_concurrent_allocations: usize,
    /// Timeout for device allocation in seconds
    pub allocation_timeout_secs: u64,
    /// Interval for health checks in seconds
    pub health_check_interval_secs: u64,
}

impl Default for DMSCResourcePoolConfig {
    fn default() -> Self {
        Self {
            name: "default_pool".to_string(),
            device_type: DMSCDeviceType::CPU,
            max_concurrent_allocations: 10,
            allocation_timeout_secs: 60,
            health_check_interval_secs: 30,
        }
    }
}

impl DMSCResourcePool {
    /// Creates a new resource pool with the given configuration
    /// 
    /// # Parameters
    /// 
    /// - `config`: The configuration for the resource pool
    /// 
    /// # Returns
    /// 
    /// A new `DMSCResourcePool` instance with the specified configuration
    pub fn new(config: DMSCResourcePoolConfig) -> Self {
        let connection_pool = Arc::new(RwLock::new(DMSCConnectionPool::new(
            config.max_concurrent_allocations,
            Duration::from_secs(config.allocation_timeout_secs),
            Duration::from_secs(config.health_check_interval_secs),
        )));
        
        Self {
            name: config.name,
            device_type: config.device_type,
            devices: HashMap::with_capacity(16),
            total_capacity: 0,
            available_capacity: 0,
            allocated_capacity: 0,
            pending_requests: 0,
            total_compute_units: 0,
            total_memory_gb: 0.0,
            total_storage_gb: 0.0,
            total_bandwidth_gbps: 0.0,
            available_compute_units: 0,
            available_memory_gb: 0.0,
            available_storage_gb: 0.0,
            available_bandwidth_gbps: 0.0,
            connection_pool,
        }
    }
    
    /// Adds a device to the pool
    /// 
    /// This method adds a device to the pool if it matches the pool's device type
    /// and is not already in the pool.
    /// 
    /// # Parameters
    /// 
    /// - `device`: The device to add to the pool
    /// 
    /// # Returns
    /// 
    /// `true` if the device was successfully added, `false` otherwise
    pub fn add_device(&mut self, device: Arc<DMSCDevice>) -> bool {
        // Check if device type matches pool device type
        if device.device_type() != self.device_type {
            return false;
        }
        
        let device_id = device.id().to_string();
        // Check if device is already in the pool
        if self.devices.contains_key(&device_id) {
            return false;
        }
        
        // Get device capabilities and extract values before inserting the device
        let compute_units = device.capabilities().compute_units.unwrap_or(0);
        let memory_gb = device.capabilities().memory_gb.unwrap_or(0.0);
        let storage_gb = device.capabilities().storage_gb.unwrap_or(0.0);
        let bandwidth_gbps = device.capabilities().bandwidth_gbps.unwrap_or(0.0);
        
        // Add device to the pool
        self.devices.insert(device_id, device);
        
        // Update capacity counters
        self.total_capacity += 1;
        self.available_capacity += 1;
        
        // Update total resource counters
        self.total_compute_units += compute_units;
        self.total_memory_gb += memory_gb;
        self.total_storage_gb += storage_gb;
        self.total_bandwidth_gbps += bandwidth_gbps;
        
        // Update available resource counters (device is available initially)
        self.available_compute_units += compute_units;
        self.available_memory_gb += memory_gb;
        self.available_storage_gb += storage_gb;
        self.available_bandwidth_gbps += bandwidth_gbps;
        
        true
    }
    
    /// Removes a device from the pool
    /// 
    /// This method removes a device from the pool by its ID, updating capacity counters
    /// based on the device's status.
    /// 
    /// # Parameters
    /// 
    /// - `device_id`: The ID of the device to remove
    /// 
    /// # Returns
    /// 
    /// `true` if the device was successfully removed, `false` otherwise
    pub fn remove_device(&mut self, device_id: &str) -> bool {
        if let Some(device) = self.devices.remove(device_id) {
            // Get device capabilities
            let capabilities = device.capabilities();
            
            // Decrement total capacity
            self.total_capacity -= 1;
            
            // Update available or allocated capacity based on device status
            if device.is_available() {
                self.available_capacity -= 1;
                
                // Update available resource counters
                self.available_compute_units -= capabilities.compute_units.unwrap_or(0);
                self.available_memory_gb -= capabilities.memory_gb.unwrap_or(0.0);
                self.available_storage_gb -= capabilities.storage_gb.unwrap_or(0.0);
                self.available_bandwidth_gbps -= capabilities.bandwidth_gbps.unwrap_or(0.0);
            } else if device.is_allocated() {
                self.allocated_capacity -= 1;
                
                // Update allocated resource counters indirectly by updating total
                // Available resources don't change when removing an allocated device
            }
            
            // Update total resource counters
            self.total_compute_units -= capabilities.compute_units.unwrap_or(0);
            self.total_memory_gb -= capabilities.memory_gb.unwrap_or(0.0);
            self.total_storage_gb -= capabilities.storage_gb.unwrap_or(0.0);
            self.total_bandwidth_gbps -= capabilities.bandwidth_gbps.unwrap_or(0.0);
            
            true
        } else {
            false
        }
    }
    
    /// Allocates a device from the pool
    /// 
    /// This method allocates the first available device from the pool, updating capacity counters.
    /// 
    /// # Parameters
    /// 
    /// - `_allocation_id`: The ID of the allocation (currently unused)
    /// 
    /// # Returns
    /// 
    /// An `Option<Arc<DMSCDevice>>` containing the allocated device if successful, `None` otherwise
    pub fn allocate(&mut self, _allocation_id: &str) -> Option<Arc<DMSCDevice>> {
        // Check if there's available capacity
        if self.available_capacity == 0 {
            return None;
        }
        
        // Find the first available device
        for device in self.devices.values() {
            // This is a simplified allocation - in a real implementation, 
            // we'd need to lock the device and check its status atomically
            if device.is_available() {
                // Get device capabilities
                let capabilities = device.capabilities();
                
                // Note: In a real implementation, we'd need to modify the device
                // to mark it as allocated. This is simplified for demonstration.
                self.available_capacity -= 1;
                self.allocated_capacity += 1;
                
                // Update available resource counters
                self.available_compute_units -= capabilities.compute_units.unwrap_or(0);
                self.available_memory_gb -= capabilities.memory_gb.unwrap_or(0.0);
                self.available_storage_gb -= capabilities.storage_gb.unwrap_or(0.0);
                self.available_bandwidth_gbps -= capabilities.bandwidth_gbps.unwrap_or(0.0);
                
                // Add connection to pool
                let mut pool = match self.connection_pool.write() {
                    Ok(pool) => pool,
                    Err(e) => {
                        log::error!("Failed to acquire connection pool lock: {}", e);
                        return None;
                    }
                };
                pool.add_connection(device.id().to_string(), device.id().to_string());
                
                return Some(device.clone());
            }
        }
        
        None
    }
    
    /// Releases a device back to the pool
    /// 
    /// This method releases a device back to the pool by its allocation ID, updating capacity counters.
    /// 
    /// # Parameters
    /// 
    /// - `allocation_id`: The ID of the allocation to release
    /// 
    /// # Returns
    /// 
    /// `true` if the device was successfully released, `false` otherwise
    pub fn release(&mut self, allocation_id: &str) -> bool {
        // Find the allocated device by allocation ID
        for device in self.devices.values() {
            if let Some(current_allocation) = device.get_allocation_id() {
                if current_allocation == allocation_id {
                    // Get device capabilities
                    let capabilities = device.capabilities();
                    
                    // Note: In a real implementation, we'd need to modify the device
                    // to mark it as released. This is simplified for demonstration.
                    self.allocated_capacity -= 1;
                    self.available_capacity += 1;
                    
                    // Update available resource counters
                    self.available_compute_units += capabilities.compute_units.unwrap_or(0);
                    self.available_memory_gb += capabilities.memory_gb.unwrap_or(0.0);
                    self.available_storage_gb += capabilities.storage_gb.unwrap_or(0.0);
                    self.available_bandwidth_gbps += capabilities.bandwidth_gbps.unwrap_or(0.0);
                    
                    // Remove connection from pool
                    match self.connection_pool.write() {
                        Ok(mut pool) => {
                            pool.remove_connection(device.id());
                        }
                        Err(e) => {
                            log::error!("Failed to acquire connection pool lock for removal: {}", e);
                            // Continue with release even if we can't update the pool
                        }
                    }
                    
                    return true;
                }
            }
        }
        
        false
    }
    
    /// Gets the current status of the pool
    /// 
    /// This method returns a DMSCResourcePoolStatus struct containing information about the pool's
    /// capacity, allocation, and utilization.
    /// 
    /// # Returns
    /// 
    /// A `DMSCResourcePoolStatus` struct with the current pool status
    pub fn get_status(&self) -> super::DMSCResourcePoolStatus {
        super::DMSCResourcePoolStatus {
            total_capacity: self.total_capacity,
            available_capacity: self.available_capacity,
            allocated_capacity: self.allocated_capacity,
            pending_requests: self.pending_requests,
            utilization_rate: if self.total_capacity > 0 {
                (self.allocated_capacity as f64 / self.total_capacity as f64) * 100.0
            } else {
                0.0
            },
        }
    }
    
    /// Gets the name of the pool
    /// 
    /// # Returns
    /// 
    /// The pool name as a string slice
    #[inline]
    pub fn name(&self) -> &str {
        &self.name
    }
    
    /// Gets the device type of the pool
    /// 
    /// # Returns
    /// 
    /// The device type as a `DMSCDeviceType` enum
    #[inline]
    pub fn device_type(&self) -> DMSCDeviceType {
        self.device_type
    }
    
    /// Gets all devices in the pool
    /// 
    /// # Returns
    /// 
    /// A vector of `Arc<DMSCDevice>` containing all devices in the pool
    #[inline]
    pub fn get_devices(&self) -> Vec<Arc<DMSCDevice>> {
        self.devices.values().cloned().collect()
    }
    
    /// Gets available devices in the pool
    /// 
    /// # Returns
    /// 
    /// A vector of `Arc<DMSCDevice>` containing only available devices
    pub fn get_available_devices(&self) -> Vec<Arc<DMSCDevice>> {
        self.devices.values()
            .filter(|device| device.is_available())
            .cloned()
            .collect()
    }
    
    /// Gets allocated devices in the pool
    /// 
    /// # Returns
    /// 
    /// A vector of `Arc<DMSCDevice>` containing only allocated devices
    pub fn get_allocated_devices(&self) -> Vec<Arc<DMSCDevice>> {
        self.devices.values()
            .filter(|device| device.is_allocated())
            .cloned()
            .collect()
    }
    
    /// Checks if the pool has available capacity
    /// 
    /// # Returns
    /// 
    /// `true` if the pool has available devices, `false` otherwise
    #[inline]
    pub fn has_available_capacity(&self) -> bool {
        self.available_capacity > 0
    }
    
    /// Gets the utilization rate of the pool (0.0 - 1.0)
    /// 
    /// # Returns
    /// 
    /// The utilization rate as a floating-point number between 0.0 and 1.0
    #[inline]
    pub fn utilization_rate(&self) -> f64 {
        if self.total_capacity > 0 {
            self.allocated_capacity as f64 / self.total_capacity as f64
        } else {
            0.0
        }
    }
    
    /// Checks if the pool is healthy
    /// 
    /// A pool is considered healthy if it has available devices or allocated devices.
    /// 
    /// # Returns
    /// 
    /// `true` if the pool is healthy, `false` otherwise
    pub fn is_healthy(&self) -> bool {
        self.available_capacity > 0 || self.allocated_capacity > 0
    }
    
    /// Gets comprehensive statistics for the pool
    /// 
    /// This method calculates and returns comprehensive statistics for the pool, including
    /// device counts, utilization, total compute units, memory, storage, bandwidth, and average health score.
    /// 
    /// # Returns
    /// 
    /// A `DMSCResourcePoolStatistics` struct with comprehensive pool statistics
    pub fn get_statistics(&self) -> DMSCResourcePoolStatistics {
        let devices = self.get_devices();
        let available_devices = self.get_available_devices();
        let allocated_devices = self.get_allocated_devices();

        // Calculate total compute units across all devices
        let total_compute_units: usize = devices.iter()
            .filter_map(|d| d.capabilities().compute_units)
            .sum();

        // Calculate total memory across all devices
        let total_memory_gb: f64 = devices.iter()
            .filter_map(|d| d.capabilities().memory_gb)
            .sum();

        // Calculate total storage across all devices
        let total_storage_gb: f64 = devices.iter()
            .filter_map(|d| d.capabilities().storage_gb)
            .sum();

        // Calculate total bandwidth across all devices
        let total_bandwidth_gbps: f64 = devices.iter()
            .filter_map(|d| d.capabilities().bandwidth_gbps)
            .sum();

        // Calculate average health score across all devices
        let average_health_score: f64 = if !devices.is_empty() {
            devices.iter()
                .map(|d| d.health_score() as f64)
                .sum::<f64>() / devices.len() as f64
        } else {
            0.0
        };

        // Get connection pool statistics
        let connection_pool_stats = match self.connection_pool.read() {
            Ok(pool) => Some(pool.get_statistics()),
            Err(e) => {
                log::error!("Failed to acquire connection pool read lock: {}", e);
                None
            }
        };
        
        // Calculate device status distribution
        let mut status_distribution = HashMap::with_capacity(4);
        for device in &devices {
            *status_distribution.entry(device.status()).or_insert(0) += 1;
        }
        
        // Calculate average health metrics
        let mut total_response_time_ms = 0.0;
        let mut total_network_latency_ms = 0.0;
        let mut total_disk_iops = 0.0;
        let mut total_battery_level_percent = 0.0;
        let mut total_cpu_usage_percent = 0.0;
        let mut total_memory_usage_percent = 0.0;
        let mut total_temperature_celsius = 0.0;
        let mut total_error_count = 0u32;
        let mut total_throughput = 0.0;
        let mut total_uptime_seconds = 0.0;
        
        for device in &devices {
            let health_metrics = device.health_metrics();
            total_response_time_ms += health_metrics.response_time_ms;
            total_network_latency_ms += health_metrics.network_latency_ms;
            total_disk_iops += health_metrics.disk_iops as f64;
            total_battery_level_percent += health_metrics.battery_level_percent;
            total_cpu_usage_percent += health_metrics.cpu_usage_percent;
            total_memory_usage_percent += health_metrics.memory_usage_percent;
            total_temperature_celsius += health_metrics.temperature_celsius;
            total_error_count += health_metrics.error_count;
            total_throughput += health_metrics.throughput as f64;
            total_uptime_seconds += health_metrics.uptime_seconds as f64;
        }
        
        let device_count = devices.len() as f64;
        
        DMSCResourcePoolStatistics {
            total_devices: devices.len(),
            available_devices: available_devices.len(),
            allocated_devices: allocated_devices.len(),
            utilization_rate: self.utilization_rate(),
            total_compute_units,
            total_memory_gb,
            total_storage_gb,
            total_bandwidth_gbps,
            average_health_score,
            device_type: self.device_type,
            connection_pool_stats,
            
            status_distribution,
            average_response_time_ms: if device_count > 0.0 { total_response_time_ms / device_count } else { 0.0 },
            average_network_latency_ms: if device_count > 0.0 { total_network_latency_ms / device_count } else { 0.0 },
            average_disk_iops: if device_count > 0.0 { total_disk_iops / device_count } else { 0.0 },
            average_battery_level_percent: if device_count > 0.0 { total_battery_level_percent / device_count } else { 0.0 },
            average_cpu_usage_percent: if device_count > 0.0 { total_cpu_usage_percent / device_count } else { 0.0 },
            average_memory_usage_percent: if device_count > 0.0 { total_memory_usage_percent / device_count } else { 0.0 },
            average_temperature_celsius: if device_count > 0.0 { total_temperature_celsius / device_count } else { 0.0 },
            total_error_count,
            average_throughput: if device_count > 0.0 { total_throughput / device_count } else { 0.0 },
            average_uptime_seconds: if device_count > 0.0 { total_uptime_seconds / device_count } else { 0.0 },
        }
    }
}

/// Connection pool for managing device connections with lifecycle and health monitoring
#[derive(Debug, Clone)]
#[allow(dead_code)]
pub struct DMSCConnectionPool {
    /// Active connections with their metadata
    connections: HashMap<String, DMSCConnectionInfo>,
    /// Maximum number of connections allowed
    max_connections: usize,
    /// Connection timeout duration
    connection_timeout: Duration,
    /// Health check interval
    health_check_interval: Duration,
    /// Last health check timestamp (seconds since Unix epoch)
    last_health_check_secs: u64,
    /// Number of active connections
    pub active_connections: usize,
    /// Number of failed connections
    pub failed_connections: usize,
    /// Total number of errors
    pub total_errors: usize,
}

/// Connection information for tracking individual connections
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DMSCConnectionInfo {
    /// Connection ID
    pub connection_id: String,
    /// Device ID this connection is associated with
    pub device_id: String,
    /// Remote address or endpoint
    pub address: String,
    /// Connection establishment timestamp (seconds since Unix epoch)
    pub established_at_secs: u64,
    /// Last activity timestamp (seconds since Unix epoch)
    pub last_activity_secs: u64,
    /// Connection state
    pub state: DMSCConnectionState,
    /// Connection health metrics
    pub health_metrics: DMSCConnectionHealthMetrics,
}

/// Connection state enumeration
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub enum DMSCConnectionState {
    /// Connection is establishing
    Connecting,
    /// Connection is active and healthy
    Active,
    /// Connection is idle (no recent activity)
    Idle,
    /// Connection is unhealthy
    Unhealthy,
    /// Connection is being closed
    Closing,
    /// Connection is closed
    Closed,
}

/// Connection health metrics
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct DMSCConnectionHealthMetrics {
    /// Number of successful operations
    pub successful_operations: u64,
    /// Number of failed operations
    pub failed_operations: u64,
    /// Average response time in milliseconds
    pub average_response_time_ms: f64,
    /// Last error timestamp (seconds since Unix epoch)
    pub last_error_secs: Option<u64>,
    /// Connection uptime percentage
    pub uptime_percentage: f64,
}

#[allow(dead_code)]
impl DMSCConnectionPool {
    /// Creates a new connection pool
    pub fn new(max_connections: usize, connection_timeout: Duration, health_check_interval: Duration) -> Self {
        Self {
            connections: HashMap::with_capacity(max_connections),
            max_connections,
            connection_timeout,
            health_check_interval,
            last_health_check_secs: std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or(Duration::from_secs(0))
                .as_secs(),
            active_connections: 0,
            failed_connections: 0,
            total_errors: 0,
        }
    }
    
    /// Adds a new connection to the pool
    pub fn add_connection(&mut self, device_id: String, address: String) {
        let connection_info = DMSCConnectionInfo {
            connection_id: device_id.clone(),
            device_id: device_id.clone(),
            address,
            established_at_secs: std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or_default()
                .as_secs(),
            last_activity_secs: std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or_default()
                .as_secs(),
            state: DMSCConnectionState::Active,
            health_metrics: DMSCConnectionHealthMetrics::default(),
        };
        
        self.connections.insert(device_id, connection_info);
        self.active_connections += 1;
    }
    
    /// Removes a connection from the pool
    pub fn remove_connection(&mut self, connection_id: &str) -> bool {
        self.connections.remove(connection_id).is_some()
    }
    
    /// Gets connection information
    pub fn get_connection(&self, connection_id: &str) -> Option<&DMSCConnectionInfo> {
        self.connections.get(connection_id)
    }
    
    /// Updates connection activity
    pub fn update_activity(&mut self, connection_id: &str) -> bool {
        if let Some(connection) = self.connections.get_mut(connection_id) {
            connection.last_activity_secs = std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or(Duration::from_secs(0))
                .as_secs();
            if connection.state == DMSCConnectionState::Idle {
                connection.state = DMSCConnectionState::Active;
            }
            true
        } else {
            false
        }
    }
    
    /// Updates connection health metrics
    pub fn update_health_metrics(&mut self, connection_id: &str, success: bool, response_time_ms: f64) -> bool {
        if let Some(connection) = self.connections.get_mut(connection_id) {
            if success {
                connection.health_metrics.successful_operations += 1;
            } else {
                connection.health_metrics.failed_operations += 1;
                connection.health_metrics.last_error_secs = Some(
                    std::time::SystemTime::now()
                        .duration_since(std::time::UNIX_EPOCH)
                        .unwrap_or(Duration::from_secs(0))
                        .as_secs()
                );
            }
            
            // Update average response time
            let total_ops = connection.health_metrics.successful_operations + connection.health_metrics.failed_operations;
            connection.health_metrics.average_response_time_ms = 
                (connection.health_metrics.average_response_time_ms * (total_ops - 1) as f64 + response_time_ms) / total_ops as f64;
            
            // Update uptime percentage
            let total_ops = connection.health_metrics.successful_operations + connection.health_metrics.failed_operations;
            connection.health_metrics.uptime_percentage = 
                (connection.health_metrics.successful_operations as f64 / total_ops as f64) * 100.0;
            
            true
        } else {
            false
        }
    }
    
    /// Performs health check on all connections
    pub fn perform_health_check(&mut self) {
        self.last_health_check_secs = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap_or(Duration::from_secs(0))
            .as_secs();
        
        for connection in self.connections.values_mut() {
            // Check for idle connections
            let current_time = std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .unwrap_or_default()
                .as_secs();
            let elapsed_secs = current_time.saturating_sub(connection.last_activity_secs);
            
            if connection.state == DMSCConnectionState::Active && elapsed_secs > self.connection_timeout.as_secs() {
                connection.state = DMSCConnectionState::Idle;
            }
            
            // Check for unhealthy connections
            if connection.health_metrics.uptime_percentage < 90.0 {
                connection.state = DMSCConnectionState::Unhealthy;
            } else if let Some(last_error_secs) = connection.health_metrics.last_error_secs {
                let current_secs = std::time::SystemTime::now()
                    .duration_since(std::time::UNIX_EPOCH)
                    .unwrap_or(Duration::from_secs(0))
                    .as_secs();
                if current_secs.saturating_sub(last_error_secs) < 60 {
                    connection.state = DMSCConnectionState::Unhealthy;
                }
            }
            
            // Close connections that have been unhealthy for too long
            if connection.state == DMSCConnectionState::Unhealthy &&
               connection.health_metrics.failed_operations > 10 {
                connection.state = DMSCConnectionState::Closing;
            }
        }
        
        // Remove closed connections
        self.connections.retain(|_, conn| conn.state != DMSCConnectionState::Closed);
    }
    
    /// Gets the number of active connections
    pub fn active_connections(&self) -> usize {
        self.connections.values()
            .filter(|conn| conn.state == DMSCConnectionState::Active)
            .count()
    }
    
    /// Gets the number of idle connections
    pub fn idle_connections(&self) -> usize {
        self.connections.values()
            .filter(|conn| conn.state == DMSCConnectionState::Idle)
            .count()
    }
    
    /// Gets the number of unhealthy connections
    pub fn unhealthy_connections(&self) -> usize {
        self.connections.values()
            .filter(|conn| conn.state == DMSCConnectionState::Unhealthy)
            .count()
    }
    
    /// Gets overall connection pool statistics
    pub fn get_statistics(&self) -> DMSCConnectionPoolStatistics {
        let total_connections = self.connections.len();
        let active_connections = self.active_connections();
        let idle_connections = self.idle_connections();
        let unhealthy_connections = self.unhealthy_connections();
        
        let total_successful_ops: u64 = self.connections.values()
            .map(|conn| conn.health_metrics.successful_operations)
            .sum();
        let total_failed_ops: u64 = self.connections.values()
            .map(|conn| conn.health_metrics.failed_operations)
            .sum();
        
        let avg_response_time = if !self.connections.is_empty() {
            let total_response_time: f64 = self.connections.values()
                .map(|conn| conn.health_metrics.average_response_time_ms)
                .sum();
            total_response_time / self.connections.len() as f64
        } else {
            0.0
        };
        
        let last_health_check_secs = self.last_health_check_secs;
        
        DMSCConnectionPoolStatistics {
            total_connections,
            active_connections,
            idle_connections,
            unhealthy_connections,
            available_slots: self.max_connections.saturating_sub(total_connections),
            total_successful_operations: total_successful_ops,
            total_failed_operations: total_failed_ops,
            average_response_time_ms: avg_response_time,
            health_check_interval_secs: self.health_check_interval.as_secs(),
            last_health_check_secs,
        }
    }
}

/// Connection pool statistics
#[derive(Debug, Clone, Serialize, Deserialize)]
#[cfg_attr(feature = "pyo3", pyo3::prelude::pyclass(get_all, set_all))]
pub struct DMSCConnectionPoolStatistics {
    /// Total number of connections
    pub total_connections: usize,
    /// Number of active connections
    pub active_connections: usize,
    /// Number of idle connections
    pub idle_connections: usize,
    /// Number of unhealthy connections
    pub unhealthy_connections: usize,
    /// Number of available connection slots
    pub available_slots: usize,
    /// Total successful operations across all connections
    pub total_successful_operations: u64,
    /// Total failed operations across all connections
    pub total_failed_operations: u64,
    /// Average response time across all connections
    pub average_response_time_ms: f64,
    /// Health check interval in seconds
    pub health_check_interval_secs: u64,
    /// Last health check timestamp (seconds since Unix epoch)
    pub last_health_check_secs: u64,
}

impl Default for DMSCConnectionPoolStatistics {
    fn default() -> Self {
        Self {
            total_connections: 0,
            active_connections: 0,
            idle_connections: 0,
            unhealthy_connections: 0,
            available_slots: 0,
            total_successful_operations: 0,
            total_failed_operations: 0,
            average_response_time_ms: 0.0,
            health_check_interval_secs: 0,
            last_health_check_secs: 0,
        }
    }
}

/// Resource pool statistics structure
/// 
/// This struct contains comprehensive statistics for a resource pool, including device counts,
/// utilization, total resources, and detailed health metrics.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[cfg_attr(feature = "pyo3", pyo3::prelude::pyclass(get_all, set_all))]
pub struct DMSCResourcePoolStatistics {
    /// Total number of devices in the pool
    pub total_devices: usize,
    /// Number of available devices in the pool
    pub available_devices: usize,
    /// Number of allocated devices in the pool
    pub allocated_devices: usize,
    /// Utilization rate of the pool (0.0 - 1.0)
    pub utilization_rate: f64,
    /// Total compute units across all devices
    pub total_compute_units: usize,
    /// Total memory in gigabytes across all devices
    pub total_memory_gb: f64,
    /// Total storage in gigabytes across all devices
    pub total_storage_gb: f64,
    /// Total bandwidth in gigabits per second across all devices
    pub total_bandwidth_gbps: f64,
    /// Average health score across all devices
    pub average_health_score: f64,
    /// Type of devices in the pool
    pub device_type: DMSCDeviceType,
    /// Connection pool statistics
    pub connection_pool_stats: Option<DMSCConnectionPoolStatistics>,
    
    /// Device status distribution
    pub status_distribution: HashMap<DMSCDeviceStatus, usize>,
    /// Average response time in milliseconds
    pub average_response_time_ms: f64,
    /// Average network latency in milliseconds (for network devices)
    pub average_network_latency_ms: f64,
    /// Average disk IOPS (for storage devices)
    pub average_disk_iops: f64,
    /// Average battery level percentage (for battery-powered devices)
    pub average_battery_level_percent: f64,
    /// Average CPU usage percentage
    pub average_cpu_usage_percent: f64,
    /// Average memory usage percentage
    pub average_memory_usage_percent: f64,
    /// Average temperature in Celsius
    pub average_temperature_celsius: f64,
    /// Total error count across all devices
    pub total_error_count: u32,
    /// Average throughput across all devices
    pub average_throughput: f64,
    /// Average uptime in seconds
    pub average_uptime_seconds: f64,
}

impl Default for DMSCResourcePoolStatistics {
    fn default() -> Self {
        Self {
            total_devices: 0,
            available_devices: 0,
            allocated_devices: 0,
            utilization_rate: 0.0,
            total_compute_units: 0,
            total_memory_gb: 0.0,
            total_storage_gb: 0.0,
            total_bandwidth_gbps: 0.0,
            average_health_score: 0.0,
            device_type: DMSCDeviceType::CPU,
            connection_pool_stats: None,
            status_distribution: HashMap::with_capacity(4),
            average_response_time_ms: 0.0,
            average_network_latency_ms: 0.0,
            average_disk_iops: 0.0,
            average_battery_level_percent: 0.0,
            average_cpu_usage_percent: 0.0,
            average_memory_usage_percent: 0.0,
            average_temperature_celsius: 0.0,
            total_error_count: 0,
            average_throughput: 0.0,
            average_uptime_seconds: 0.0,
        }
    }
}

/// Resource pool manager for managing multiple resource pools
/// 
/// This struct manages multiple resource pools, providing methods for creating, retrieving,
/// and removing pools, as well as getting overall statistics.
#[cfg_attr(feature = "pyo3", pyo3::prelude::pyclass)]
pub struct DMSCResourcePoolManager {
    /// Map of pool names to resource pools
    pools: HashMap<String, Arc<DMSCResourcePool>>,
}

impl Default for DMSCResourcePoolManager {
    fn default() -> Self {
        Self::new()
    }
}

impl DMSCResourcePoolManager {
    /// Creates a new resource pool manager
    /// 
    /// # Returns
    /// 
    /// A new `DMSCResourcePoolManager` instance
    pub fn new() -> Self {
        Self {
            pools: HashMap::with_capacity(8),
        }
    }
    
    /// Creates a new resource pool
    /// 
    /// This method creates a new resource pool with the given configuration and adds it to the manager.
    /// 
    /// # Parameters
    /// 
    /// - `config`: The configuration for the new resource pool
    /// 
    /// # Returns
    /// 
    /// An `Arc<DMSCResourcePool>` to the newly created pool
    pub fn create_pool(&mut self, config: DMSCResourcePoolConfig) -> Arc<DMSCResourcePool> {
        let pool = Arc::new(DMSCResourcePool::new(config));
        self.pools.insert(pool.name().to_string(), pool.clone());
        pool
    }
    
    /// Gets a resource pool by name
    /// 
    /// # Parameters
    /// 
    /// - `name`: The name of the resource pool to get
    /// 
    /// # Returns
    /// 
    /// An `Option<Arc<DMSCResourcePool>>` containing the pool if found, `None` otherwise
    pub fn get_pool(&self, name: &str) -> Option<Arc<DMSCResourcePool>> {
        self.pools.get(name).cloned()
    }
    
    /// Removes a resource pool by name
    /// 
    /// # Parameters
    /// 
    /// - `name`: The name of the resource pool to remove
    /// 
    /// # Returns
    /// 
    /// An `Option<Arc<DMSCResourcePool>>` containing the removed pool if found, `None` otherwise
    pub fn remove_pool(&mut self, name: &str) -> Option<Arc<DMSCResourcePool>> {
        self.pools.remove(name)
    }
    
    /// Gets all resource pools
    /// 
    /// # Returns
    /// 
    /// A vector of `Arc<DMSCResourcePool>` containing all resource pools
    pub fn get_all_pools(&self) -> Vec<Arc<DMSCResourcePool>> {
        self.pools.values().cloned().collect()
    }
    
    /// Gets all resource pools of a specific device type
    /// 
    /// # Parameters
    /// 
    /// - `device_type`: The device type to filter pools by
    /// 
    /// # Returns
    /// 
    /// A vector of `Arc<DMSCResourcePool>` containing all pools of the specified device type
    pub fn get_pools_by_type(&self, device_type: DMSCDeviceType) -> Vec<Arc<DMSCResourcePool>> {
        self.pools.values()
            .filter(|pool| pool.device_type() == device_type)
            .cloned()
            .collect()
    }
    
    /// Gets overall statistics for all resource pools
    /// 
    /// This method calculates and returns overall statistics for all resource pools, including
    /// total devices, utilization, and total resources across all pools.
    /// 
    /// # Returns
    /// 
    /// A `DMSCResourcePoolStatistics` struct with overall statistics for all pools
    pub fn get_overall_statistics(&self) -> DMSCResourcePoolStatistics {
        let pools = self.get_all_pools();
        
        // Calculate total devices and allocated devices across all pools
        let total_devices: usize = pools.iter().map(|p| p.get_statistics().total_devices).sum();
        let allocated_devices: usize = pools.iter().map(|p| p.get_statistics().allocated_devices).sum();
        
        // Calculate total compute units across all devices in all pools
        let total_compute_units: usize = pools.iter()
            .flat_map(|p| p.get_devices())
            .filter_map(|d| d.capabilities().compute_units)
            .sum();
        
        // Calculate total memory across all devices in all pools
        let total_memory_gb: f64 = pools.iter()
            .flat_map(|p| p.get_devices())
            .filter_map(|d| d.capabilities().memory_gb)
            .sum();
        
        // Calculate total storage across all devices in all pools
        let total_storage_gb: f64 = pools.iter()
            .flat_map(|p| p.get_devices())
            .filter_map(|d| d.capabilities().storage_gb)
            .sum();
        
        // Calculate total bandwidth across all devices in all pools
        let total_bandwidth_gbps: f64 = pools.iter()
            .flat_map(|p| p.get_devices())
            .filter_map(|d| d.capabilities().bandwidth_gbps)
            .sum();
        
        // Calculate overall utilization rate
        let overall_utilization = if total_devices > 0 {
            allocated_devices as f64 / total_devices as f64
        } else {
            0.0
        };
        
        // Calculate average health score across all pools
        let total_health_score: f64 = pools.iter()
            .map(|p| p.get_statistics().average_health_score)
            .sum();
        let average_health_score = if !pools.is_empty() {
            total_health_score / pools.len() as f64
        } else {
            0.0
        };
        
        DMSCResourcePoolStatistics {
            total_devices,
            available_devices: total_devices - allocated_devices,
            allocated_devices,
            utilization_rate: overall_utilization,
            total_compute_units,
            total_memory_gb,
            total_storage_gb,
            total_bandwidth_gbps,
            average_health_score,
            device_type: DMSCDeviceType::Custom, // Multiple device types across pools
            connection_pool_stats: None, // No aggregated connection stats at manager level
            
            status_distribution: HashMap::with_capacity(4),
            average_response_time_ms: 0.0,
            average_network_latency_ms: 0.0,
            average_disk_iops: 0.0,
            average_battery_level_percent: 0.0,
            average_cpu_usage_percent: 0.0,
            average_memory_usage_percent: 0.0,
            average_temperature_celsius: 0.0,
            total_error_count: 0,
            average_throughput: 0.0,
            average_uptime_seconds: 0.0,
        }
    }
}

#[cfg(feature = "pyo3")]
#[pyo3::prelude::pymethods]
impl DMSCResourcePoolConfig {
    #[new]
    fn py_new() -> Self {
        Self::default()
    }
    
    #[staticmethod]
    fn py_new_with_name(name: String, device_type: DMSCDeviceType) -> Self {
        Self {
            name,
            device_type,
            max_concurrent_allocations: 10,
            allocation_timeout_secs: 60,
            health_check_interval_secs: 30,
        }
    }
}

#[cfg(feature = "pyo3")]
#[pyo3::prelude::pymethods]
impl DMSCResourcePoolStatistics {
    #[new]
    fn py_new() -> Self {
        Self::default()
    }
}

#[cfg(feature = "pyo3")]
#[pyo3::prelude::pymethods]
impl DMSCResourcePoolManager {
    #[new]
    fn py_new() -> Self {
        Self::new()
    }
}