trustformers-mobile 0.1.1

//! Communication protocols and network management
//!
//! This module implements communication protocols, compression algorithms,
//! transport security, and bandwidth management for federated learning.

use serde::{Deserialize, Serialize};
use std::collections::{HashMap, VecDeque};
use crate::federated_learning_v2_backup::types::*;
use trustformers_core::{Result, CoreError};

/// Communication protocol configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CommunicationProtocolConfig {
    /// Communication protocol to use
    pub protocol: CommunicationProtocol,
    /// Transport security settings
    pub transport_security: TransportSecurityConfig,
    /// Compression configuration
    pub compression: CompressionConfig,
    /// Bandwidth management settings
    pub bandwidth_management: BandwidthManagementConfig,
    /// Message queue configuration
    pub message_queue: MessageQueueConfig,
    /// Timeout settings
    pub timeout_config: TimeoutConfig,
}

/// Transport security configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TransportSecurityConfig {
    /// Security protocol
    pub protocol: TransportSecurity,
    /// Certificate validation enabled
    pub certificate_validation: bool,
    /// Mutual TLS enabled
    pub mutual_tls: bool,
    /// Cipher suites
    pub cipher_suites: Vec<String>,
    /// Protocol versions
    pub protocol_versions: Vec<String>,
}

/// Compression configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CompressionConfig {
    /// Compression algorithm
    pub algorithm: CompressionAlgorithm,
    /// Compression level (0-9)
    pub compression_level: u8,
    /// Minimum size for compression
    pub min_size_for_compression: usize,
    /// Adaptive compression enabled
    pub adaptive_compression: bool,
}

/// Bandwidth management configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct BandwidthManagementConfig {
    /// Maximum bandwidth in Mbps
    pub max_bandwidth_mbps: f64,
    /// Bandwidth adaptation strategy
    pub adaptation_strategy: BandwidthAdaptationStrategy,
    /// Congestion control enabled
    pub congestion_control: bool,
    /// Quality of service priority
    pub qos_priority: QoSPriority,
    /// Rate limiting enabled
    pub rate_limiting: bool,
}

/// Quality of service priority levels
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum QoSPriority {
    /// Low priority
    Low,
    /// Medium priority
    Medium,
    /// High priority
    High,
    /// Critical priority
    Critical,
}

/// Message queue configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct MessageQueueConfig {
    /// Queue type
    pub queue_type: MessageQueueType,
    /// Maximum queue size
    pub max_queue_size: usize,
    /// Message persistence enabled
    pub persistence: bool,
    /// Dead letter queue enabled
    pub dead_letter_queue: bool,
    /// Message TTL in seconds
    pub message_ttl_seconds: u64,
}

/// Message queue types
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum MessageQueueType {
    /// In-memory queue
    InMemory,
    /// Redis queue
    Redis,
    /// RabbitMQ
    RabbitMQ,
    /// Apache Kafka
    Kafka,
    /// MQTT
    MQTT,
}

/// Timeout configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct TimeoutConfig {
    /// Connection timeout in seconds
    pub connection_timeout_seconds: u64,
    /// Read timeout in seconds
    pub read_timeout_seconds: u64,
    /// Write timeout in seconds
    pub write_timeout_seconds: u64,
    /// Keep-alive timeout in seconds
    pub keepalive_timeout_seconds: u64,
}

/// Communication manager for federated learning
#[derive(Debug)]
pub struct CommunicationManager {
    config: CommunicationProtocolConfig,
    transport_security: TransportSecurityManager,
    compression_config: CompressionConfig,
    active_connections: HashMap<String, ConnectionInfo>,
    message_queue: VecDeque<Message>,
    bandwidth_monitor: BandwidthMonitor,
}

/// Connection information
#[derive(Debug, Clone)]
pub struct ConnectionInfo {
    /// Connection ID
    pub id: String,
    /// Remote address
    pub address: String,
    /// Connection state
    pub state: ConnectionState,
    /// Last activity timestamp
    pub last_activity: u64,
    /// Total bytes sent
    pub bytes_sent: u64,
    /// Total bytes received
    pub bytes_received: u64,
}

/// Connection states
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum ConnectionState {
    /// Connecting
    Connecting,
    /// Connected
    Connected,
    /// Disconnecting
    Disconnecting,
    /// Disconnected
    Disconnected,
    /// Error state
    Error,
}

/// Message structure for communication
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Message {
    /// Message ID
    pub id: String,
    /// Sender ID
    pub sender_id: String,
    /// Recipient ID
    pub recipient_id: String,
    /// Message type
    pub message_type: MessageType,
    /// Message payload
    pub payload: Vec<u8>,
    /// Timestamp
    pub timestamp: u64,
    /// Priority level
    pub priority: QoSPriority,
}

/// Message types
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
pub enum MessageType {
    /// Model update
    ModelUpdate,
    /// Aggregated model
    AggregatedModel,
    /// Training configuration
    TrainingConfig,
    /// Participant registration
    ParticipantRegistration,
    /// Round synchronization
    RoundSync,
    /// Heartbeat
    Heartbeat,
    /// Error message
    Error,
}

/// Transport security manager
#[derive(Debug)]
pub struct TransportSecurityManager {
    config: TransportSecurityConfig,
    certificates: HashMap<String, Vec<u8>>,
    private_keys: HashMap<String, Vec<u8>>,
}

impl TransportSecurityManager {
    /// Create a new transport security manager
    pub fn new(config: TransportSecurityConfig) -> Self {
        Self {
            config,
            certificates: HashMap::new(),
            private_keys: HashMap::new(),
        }
    }

    /// Load certificate for secure communication
    pub fn load_certificate(&mut self, name: String, certificate: Vec<u8>) -> Result<()> {
        self.certificates.insert(name, certificate);
        Ok(())
    }

    /// Load private key for secure communication
    pub fn load_private_key(&mut self, name: String, private_key: Vec<u8>) -> Result<()> {
        self.private_keys.insert(name, private_key);
        Ok(())
    }

    /// Establish secure connection
    pub fn establish_secure_connection(&self, address: &str) -> Result<String> {
        // Simplified secure connection establishment
        match self.config.protocol {
            TransportSecurity::TLS13 => self.establish_tls13_connection(address),
            TransportSecurity::DTLS => self.establish_dtls_connection(address),
            TransportSecurity::CustomEncryption => self.establish_custom_connection(address),
        }
    }

    /// Establish TLS 1.3 connection
    fn establish_tls13_connection(&self, address: &str) -> Result<String> {
        // Simplified TLS 1.3 connection (use proper TLS library in practice)
        let connection_id = format!("tls13_{}", address.replace([':', '.'], "_"));
        Ok(connection_id)
    }

    /// Establish DTLS connection
    fn establish_dtls_connection(&self, address: &str) -> Result<String> {
        // Simplified DTLS connection (use proper DTLS library in practice)
        let connection_id = format!("dtls_{}", address.replace([':', '.'], "_"));
        Ok(connection_id)
    }

    /// Establish custom encrypted connection
    fn establish_custom_connection(&self, address: &str) -> Result<String> {
        // Simplified custom encryption (implement proper encryption in practice)
        let connection_id = format!("custom_{}", address.replace([':', '.'], "_"));
        Ok(connection_id)
    }
}

impl CommunicationManager {
    /// Create a new communication manager
    pub fn new(config: CommunicationProtocolConfig) -> Result<Self> {
        Ok(Self {
            transport_security: TransportSecurityManager::new(config.transport_security.clone()),
            compression_config: config.compression.clone(),
            bandwidth_monitor: BandwidthMonitor {
                current_bandwidth_mbps: 100.0,
                bandwidth_history: VecDeque::new(),
                adaptation_strategy: config.bandwidth_management.adaptation_strategy,
                congestion_state: CongestionState::NoCongestion,
            },
            config,
            active_connections: HashMap::new(),
            message_queue: VecDeque::new(),
        })
    }

    /// Connect to a remote participant
    pub fn connect(&mut self, participant_id: &str, address: &str) -> Result<()> {
        let connection_id = self.transport_security.establish_secure_connection(address)?;

        let connection_info = ConnectionInfo {
            id: connection_id,
            address: address.to_string(),
            state: ConnectionState::Connected,
            last_activity: self.get_current_timestamp(),
            bytes_sent: 0,
            bytes_received: 0,
        };

        self.active_connections.insert(participant_id.to_string(), connection_info);
        Ok(())
    }

    /// Disconnect from a participant
    pub fn disconnect(&mut self, participant_id: &str) -> Result<()> {
        if let Some(mut connection) = self.active_connections.get_mut(participant_id) {
            connection.state = ConnectionState::Disconnected;
        }
        self.active_connections.remove(participant_id);
        Ok(())
    }

    /// Send message to a participant
    pub fn send_message(&mut self, message: Message) -> Result<()> {
        // Compress message if needed
        let compressed_message = self.compress_message(&message)?;

        // Add to message queue
        self.message_queue.push_back(compressed_message);

        // Update bandwidth monitoring
        let message_size = message.payload.len() as f64 / 1024.0 / 1024.0; // Convert to MB
        self.bandwidth_monitor.current_bandwidth_mbps += message_size;

        // Update connection statistics
        if let Some(connection) = self.active_connections.get_mut(&message.recipient_id) {
            connection.bytes_sent += message.payload.len() as u64;
            connection.last_activity = self.get_current_timestamp();
        }

        Ok(())
    }

    /// Receive message from the queue
    pub fn receive_message(&mut self) -> Option<Message> {
        if let Some(message) = self.message_queue.pop_front() {
            // Decompress message if needed
            match self.decompress_message(&message) {
                Ok(decompressed) => {
                    // Update connection statistics
                    if let Some(connection) = self.active_connections.get_mut(&message.sender_id) {
                        connection.bytes_received += message.payload.len() as u64;
                        connection.last_activity = self.get_current_timestamp();
                    }
                    Some(decompressed)
                }
                Err(_) => None,
            }
        } else {
            None
        }
    }

    /// Compress message payload
    fn compress_message(&self, message: &Message) -> Result<Message> {
        if message.payload.len() < self.compression_config.min_size_for_compression {
            return Ok(message.clone());
        }

        let compressed_payload = match self.compression_config.algorithm {
            CompressionAlgorithm::None => message.payload.clone(),
            CompressionAlgorithm::GZIP => self.gzip_compress(&message.payload)?,
            CompressionAlgorithm::LZ4 => self.lz4_compress(&message.payload)?,
            CompressionAlgorithm::Brotli => self.brotli_compress(&message.payload)?,
            CompressionAlgorithm::Custom => self.custom_compress(&message.payload)?,
        };

        let mut compressed_message = message.clone();
        compressed_message.payload = compressed_payload;
        Ok(compressed_message)
    }

    /// Decompress message payload
    fn decompress_message(&self, message: &Message) -> Result<Message> {
        let decompressed_payload = match self.compression_config.algorithm {
            CompressionAlgorithm::None => message.payload.clone(),
            CompressionAlgorithm::GZIP => self.gzip_decompress(&message.payload)?,
            CompressionAlgorithm::LZ4 => self.lz4_decompress(&message.payload)?,
            CompressionAlgorithm::Brotli => self.brotli_decompress(&message.payload)?,
            CompressionAlgorithm::Custom => self.custom_decompress(&message.payload)?,
        };

        let mut decompressed_message = message.clone();
        decompressed_message.payload = decompressed_payload;
        Ok(decompressed_message)
    }

    /// GZIP compression (simplified)
    fn gzip_compress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified GZIP compression (use proper compression library in practice)
        let mut compressed = vec![0x1f, 0x8b]; // GZIP magic number
        compressed.extend_from_slice(data);
        Ok(compressed)
    }

    /// GZIP decompression (simplified)
    fn gzip_decompress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified GZIP decompression (use proper compression library in practice)
        if data.len() < 2 || data[0] != 0x1f || data[1] != 0x8b {
            return Err(TrustformersError::InvalidConfiguration("Invalid GZIP data".to_string()).into());
        }
        Ok(data[2..].to_vec())
    }

    /// LZ4 compression (simplified)
    fn lz4_compress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified LZ4 compression (use proper compression library in practice)
        let mut compressed = vec![0x04, 0x22, 0x4d, 0x18]; // LZ4 magic number
        compressed.extend_from_slice(data);
        Ok(compressed)
    }

    /// LZ4 decompression (simplified)
    fn lz4_decompress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified LZ4 decompression (use proper compression library in practice)
        if data.len() < 4 {
            return Err(TrustformersError::InvalidConfiguration("Invalid LZ4 data".to_string()).into());
        }
        Ok(data[4..].to_vec())
    }

    /// Brotli compression (simplified)
    fn brotli_compress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified Brotli compression (use proper compression library in practice)
        let mut compressed = vec![0xce, 0xb2, 0xcf, 0x81]; // Simplified Brotli header
        compressed.extend_from_slice(data);
        Ok(compressed)
    }

    /// Brotli decompression (simplified)
    fn brotli_decompress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified Brotli decompression (use proper compression library in practice)
        if data.len() < 4 {
            return Err(TrustformersError::InvalidConfiguration("Invalid Brotli data".to_string()).into());
        }
        Ok(data[4..].to_vec())
    }

    /// Custom compression (simplified)
    fn custom_compress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified custom compression (implement proper algorithm in practice)
        Ok(data.to_vec())
    }

    /// Custom decompression (simplified)
    fn custom_decompress(&self, data: &[u8]) -> Result<Vec<u8>> {
        // Simplified custom decompression (implement proper algorithm in practice)
        Ok(data.to_vec())
    }

    /// Update bandwidth monitoring
    pub fn update_bandwidth_monitoring(&mut self) {
        // Update bandwidth history
        self.bandwidth_monitor.bandwidth_history.push_back(self.bandwidth_monitor.current_bandwidth_mbps);

        // Keep only recent history
        if self.bandwidth_monitor.bandwidth_history.len() > 100 {
            self.bandwidth_monitor.bandwidth_history.pop_front();
        }

        // Detect congestion
        let avg_bandwidth: f64 = self.bandwidth_monitor.bandwidth_history.iter().sum::<f64>()
            / self.bandwidth_monitor.bandwidth_history.len() as f64;

        self.bandwidth_monitor.congestion_state = if avg_bandwidth > 80.0 {
            CongestionState::HeavyCongestion
        } else if avg_bandwidth > 60.0 {
            CongestionState::ModerateCongestion
        } else if avg_bandwidth > 40.0 {
            CongestionState::LightCongestion
        } else {
            CongestionState::NoCongestion
        };

        // Apply adaptation strategy
        match self.bandwidth_monitor.adaptation_strategy {
            BandwidthAdaptationStrategy::Conservative => {
                if self.bandwidth_monitor.congestion_state != CongestionState::NoCongestion {
                    self.bandwidth_monitor.current_bandwidth_mbps *= 0.9;
                }
            }
            BandwidthAdaptationStrategy::Aggressive => {
                match self.bandwidth_monitor.congestion_state {
                    CongestionState::NoCongestion => {
                        self.bandwidth_monitor.current_bandwidth_mbps *= 1.1;
                    }
                    _ => {
                        self.bandwidth_monitor.current_bandwidth_mbps *= 0.8;
                    }
                }
            }
            BandwidthAdaptationStrategy::Hybrid => {
                match self.bandwidth_monitor.congestion_state {
                    CongestionState::NoCongestion => {
                        self.bandwidth_monitor.current_bandwidth_mbps *= 1.05;
                    }
                    CongestionState::LightCongestion => {
                        self.bandwidth_monitor.current_bandwidth_mbps *= 0.95;
                    }
                    _ => {
                        self.bandwidth_monitor.current_bandwidth_mbps *= 0.85;
                    }
                }
            }
        }

        // Reset current bandwidth for next measurement
        self.bandwidth_monitor.current_bandwidth_mbps = 0.0;
    }

    /// Get connection statistics
    pub fn get_connection_statistics(&self) -> HashMap<String, ConnectionInfo> {
        self.active_connections.clone()
    }

    /// Get bandwidth monitor
    pub fn get_bandwidth_monitor(&self) -> &BandwidthMonitor {
        &self.bandwidth_monitor
    }

    /// Get current timestamp (simplified)
    fn get_current_timestamp(&self) -> u64 {
        // Simplified timestamp (use proper time library in practice)
        std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap_or_default()
            .as_secs()
    }

    /// Check connection health
    pub fn check_connection_health(&mut self) -> Result<()> {
        let current_time = self.get_current_timestamp();
        let timeout = self.config.timeout_config.keepalive_timeout_seconds;

        // Check for stale connections
        let mut stale_connections = Vec::new();
        for (participant_id, connection) in &self.active_connections {
            if current_time - connection.last_activity > timeout {
                stale_connections.push(participant_id.clone().into());
            }
        }

        // Mark stale connections as disconnected
        for participant_id in stale_connections {
            if let Some(connection) = self.active_connections.get_mut(&participant_id) {
                connection.state = ConnectionState::Error;
            }
        }

        Ok(())
    }
}

impl Default for CommunicationProtocolConfig {
    fn default() -> Self {
        Self {
            protocol: CommunicationProtocol::default(),
            transport_security: TransportSecurityConfig::default(),
            compression: CompressionConfig::default(),
            bandwidth_management: BandwidthManagementConfig::default(),
            message_queue: MessageQueueConfig::default(),
            timeout_config: TimeoutConfig::default(),
        }
    }
}

impl Default for TransportSecurityConfig {
    fn default() -> Self {
        Self {
            protocol: TransportSecurity::default(),
            certificate_validation: true,
            mutual_tls: false,
            cipher_suites: vec!["TLS_AES_256_GCM_SHA384".to_string()],
            protocol_versions: vec!["TLSv1.3".to_string()],
        }
    }
}

impl Default for CompressionConfig {
    fn default() -> Self {
        Self {
            algorithm: CompressionAlgorithm::default(),
            compression_level: 6,
            min_size_for_compression: 1024,
            adaptive_compression: true,
        }
    }
}

impl Default for BandwidthManagementConfig {
    fn default() -> Self {
        Self {
            max_bandwidth_mbps: 100.0,
            adaptation_strategy: BandwidthAdaptationStrategy::default(),
            congestion_control: true,
            qos_priority: QoSPriority::Medium,
            rate_limiting: true,
        }
    }
}

impl Default for MessageQueueConfig {
    fn default() -> Self {
        Self {
            queue_type: MessageQueueType::InMemory,
            max_queue_size: 10000,
            persistence: false,
            dead_letter_queue: false,
            message_ttl_seconds: 3600,
        }
    }
}

impl Default for TimeoutConfig {
    fn default() -> Self {
        Self {
            connection_timeout_seconds: 30,
            read_timeout_seconds: 60,
            write_timeout_seconds: 60,
            keepalive_timeout_seconds: 300,
        }
    }
}

impl Default for QoSPriority {
    fn default() -> Self {
        Self::Medium
    }
}

impl Default for MessageQueueType {
    fn default() -> Self {
        Self::InMemory
    }
}