Improve code organization and documentation (#325)

* Add MARK headers to improve code organization in major files * Reorganize peer management functions in BluetoothMeshService - Removed duplicate getCurrentPeerID(for:) function - Consolidated peer identity functions in Peer Identity Mapping section - Moved getPeerFingerprint(), getFingerprint(for:), isPeerIDOurs() to proper location - Moved getCurrentPeerIDForFingerprint() and getCurrentPeerIDs() from Message Sending section - Moved notifyPeerIDChange() to Peer Management section * Consolidate peer management functions in BluetoothMeshService - Moved getCachedPublicKey() and getCachedSigningKey() from Identity Cache Methods to Peer Connection Management - Moved getPeerNicknames() and getPeerRSSI() to Peer Connection Management section - Moved getAllConnectedPeerIDs(), notifyPeerListUpdate(), and cleanupStalePeers() to Peer Connection Management - Removed duplicate function declarations after consolidation - Improved code organization by grouping all peer-related functions together * Consolidate message handling functions in ChatViewModel - Moved handleHandshakeRequest() from floating location to Message Reception section - Moved trimMessagesIfNeeded() and trimPrivateChatMessagesIfNeeded() to Message Batching section - Improved code organization by grouping related message handling functions together - Removed unnecessary comments from trim functions * Improve ContentView organization with better documentation - Added descriptive comments for complex inline computations - Documented message extraction logic for private vs public chats - Documented peer data computation and sorting logic - Improved code readability by explaining complex operations inline - Note: Attempted to extract complex computations into helper functions, but SwiftUI scope limitations made inline documentation a better approach --------- Co-authored-by: jack <jackjackbits@users.noreply.github.com>
2026-07-25 22:25:20 +00:00 · 2025-07-26 00:11:23 +02:00
parent 4568951736
commit 54c7eba8cb
4 changed files with 310 additions and 137 deletions
@@ -9,6 +9,8 @@
 import Foundation
 import CryptoKit

+// MARK: - Message Padding
+
 // Privacy-preserving padding utilities
 struct MessagePadding {
    // Standard block sizes for padding
@@ -75,6 +77,8 @@ struct MessagePadding {
    }
 }

+// MARK: - Message Types
+
 enum MessageType: UInt8 {
    case announce = 0x01
    case leave = 0x03
@@ -127,6 +131,8 @@ enum MessageType: UInt8 {
    }
 }

+// MARK: - Handshake State
+
 // Lazy handshake state tracking
 enum LazyHandshakeState {
    case none                    // No session, no handshake attempted
@@ -136,11 +142,15 @@ enum LazyHandshakeState {
    case failed(Error)         // Handshake failed
 }

+// MARK: - Special Recipients
+
 // Special recipient ID for broadcast messages
 struct SpecialRecipients {
    static let broadcast = Data(repeating: 0xFF, count: 8)  // All 0xFF = broadcast
 }

+// MARK: - Core Protocol Structures
+
 struct BitchatPacket: Codable {
    let version: UInt8
    let type: UInt8
@@ -197,6 +207,8 @@ struct BitchatPacket: Codable {
    }
 }

+// MARK: - Delivery Acknowledgments
+
 // Delivery acknowledgment structure
 struct DeliveryAck: Codable {
    let originalMessageID: String
@@ -287,6 +299,8 @@ struct DeliveryAck: Codable {
    }
 }

+// MARK: - Read Receipts
+
 // Read receipt structure
 struct ReadReceipt: Codable {
    let originalMessageID: String
@@ -371,6 +385,8 @@ struct ReadReceipt: Codable {
    }
 }

+// MARK: - Handshake Requests
+
 // Handshake request for pending messages
 struct HandshakeRequest: Codable {
    let requestID: String
@@ -1031,6 +1047,8 @@ struct VersionAck: Codable {
    }
 }

+// MARK: - Delivery Status
+
 // Delivery status for messages
 enum DeliveryStatus: Codable, Equatable {
    case sending
@@ -1058,6 +1076,8 @@ enum DeliveryStatus: Codable, Equatable {
    }
 }

+// MARK: - Message Model
+
 class BitchatMessage: Codable {
    let id: String
    let sender: String
@@ -1120,6 +1140,8 @@ extension BitchatMessage: Equatable {
    }
 }

+// MARK: - Delegate Protocol
+
 protocol BitchatDelegate: AnyObject {
    func didReceiveMessage(_ message: BitchatMessage)
    func didConnectToPeer(_ peerID: String)
@@ -65,27 +65,39 @@ enum PeerConnectionState: CustomStringConvertible {
 }

 class BluetoothMeshService: NSObject {
+    // MARK: - Constants
+    
    static let serviceUUID = CBUUID(string: "F47B5E2D-4A9E-4C5A-9B3F-8E1D2C3A4B5C")
    static let characteristicUUID = CBUUID(string: "A1B2C3D4-E5F6-4A5B-8C9D-0E1F2A3B4C5D")
    
+    // MARK: - Core Bluetooth Properties
    
    private var centralManager: CBCentralManager?
    private var peripheralManager: CBPeripheralManager?
    private var discoveredPeripherals: [CBPeripheral] = []
    private var connectedPeripherals: [String: CBPeripheral] = [:]
    private var peripheralCharacteristics: [CBPeripheral: CBCharacteristic] = [:]
+    
+    // MARK: - Connection Tracking
+    
    private var lastConnectionTime: [String: Date] = [:] // Track when peers last connected
    private var lastSuccessfulMessageTime: [String: Date] = [:] // Track last successful message exchange
    private var lastHeardFromPeer: [String: Date] = [:] // Track last time we received ANY packet from peer
    
+    // MARK: - Peer Availability
+    
    // Peer availability tracking
    private var peerAvailabilityState: [String: Bool] = [:]  // true = available, false = unavailable
    private let peerAvailabilityTimeout: TimeInterval = 30.0  // Mark unavailable after 30s of no response
    private var availabilityCheckTimer: Timer?
    
+    // MARK: - Peripheral Management
+    
    private var characteristic: CBMutableCharacteristic?
    private var subscribedCentrals: [CBCentral] = []
-    // Thread-safe collections using concurrent queues
+    
+    // MARK: - Thread-Safe Collections
+    
    private let collectionsQueue = DispatchQueue(label: "bitchat.collections", attributes: .concurrent)
    private var peerNicknames: [String: String] = [:]
    private var activePeers: Set<String> = []  // Track all active peers
@@ -93,6 +105,8 @@ class BluetoothMeshService: NSObject {
    private var peripheralRSSI: [String: NSNumber] = [:] // Track RSSI by peripheral ID during discovery
    private var rssiRetryCount: [String: Int] = [:] // Track RSSI retry attempts per peripheral
    
+    // MARK: - Encryption Queues
+    
    // Per-peer encryption queues to prevent nonce desynchronization
    private var peerEncryptionQueues: [String: DispatchQueue] = [:]
    private let encryptionQueuesLock = NSLock()
@@ -115,10 +129,14 @@ class BluetoothMeshService: NSObject {
    private let identityCacheTTL: TimeInterval = 3600.0  // 1 hour TTL
    private var identityCacheTimestamps: [String: Date] = [:]  // Track when entries were cached
    
+    // MARK: - Delegates and Services
+    
    weak var delegate: BitchatDelegate?
    private let noiseService = NoiseEncryptionService()
    private let handshakeCoordinator = NoiseHandshakeCoordinator()
    
+    // MARK: - Protocol Version Negotiation
+    
    // Protocol version negotiation state
    private var versionNegotiationState: [String: VersionNegotiationState] = [:]
    private var negotiatedVersions: [String: UInt8] = [:]  // peerID -> agreed version
@@ -147,29 +165,6 @@ class BluetoothMeshService: NSObject {
        return noiseService
    }
    
-    // MARK: - Identity Cache Methods
-    
-    func getCachedPublicKey(for peerID: String) -> Data? {
-        return collectionsQueue.sync {
-            // Check if cache entry exists and is not expired
-            if let timestamp = identityCacheTimestamps[peerID],
-               Date().timeIntervalSince(timestamp) < identityCacheTTL {
-                return peerPublicKeyCache[peerID]
-            }
-            return nil
-        }
-    }
-    
-    func getCachedSigningKey(for peerID: String) -> Data? {
-        return collectionsQueue.sync {
-            // Check if cache entry exists and is not expired
-            if let timestamp = identityCacheTimestamps[peerID],
-               Date().timeIntervalSince(timestamp) < identityCacheTTL {
-                return peerSigningKeyCache[peerID]
-            }
-            return nil
-        }
-    }
    
    private func cleanExpiredIdentityCache() {
        collectionsQueue.async(flags: .barrier) { [weak self] in
@@ -314,6 +309,8 @@ class BluetoothMeshService: NSObject {
                           category: SecureLogger.session, level: .debug)
        }
    }
+    // MARK: - Message Processing
+    
    private let messageQueue = DispatchQueue(label: "bitchat.messageQueue", attributes: .concurrent) // Concurrent queue with barriers
    
    // Message state tracking for better duplicate detection
@@ -338,6 +335,8 @@ class BluetoothMeshService: NSObject {
    private var recentIdentityAnnounces = [String: Date]()  // peerID -> last seen time
    private let identityAnnounceDuplicateWindow: TimeInterval = 30.0  // 30 second window
    
+    // MARK: - Network State Management
+    
    private let maxTTL: UInt8 = 7  // Maximum hops for long-distance delivery
    private var announcedToPeers = Set<String>()  // Track which peers we've announced to
    private var announcedPeers = Set<String>()  // Track peers who have already been announced
@@ -353,6 +352,8 @@ class BluetoothMeshService: NSObject {
    private var peerLastSeenTimestamps = LRUCache<String, Date>(maxSize: 100)  // Bounded cache for peer timestamps
    private var cleanupTimer: Timer?  // Timer to clean up stale peers
    
+    // MARK: - Store-and-Forward Cache
+    
    // Store-and-forward message cache
    private struct StoredMessage {
        let packet: BitchatPacket
@@ -372,6 +373,8 @@ class BluetoothMeshService: NSObject {
    private let lastMessageFromPeer = LRUCache<String, Date>(maxSize: 100)  // Bounded cache
    private let processedNoiseMessages = BoundedSet<String>(maxSize: 1000)  // Bounded cache
    
+    // MARK: - Battery and Performance Optimization
+    
    // Battery and range optimizations
    private var scanDutyCycleTimer: Timer?
    private var isActivelyScanning = true
@@ -400,18 +403,26 @@ class BluetoothMeshService: NSObject {
    // Pending private messages waiting for handshake
    private var pendingPrivateMessages: [String: [(content: String, recipientNickname: String, messageID: String)]] = [:]
    
+    // MARK: - Noise Protocol State
+    
    // Noise session state tracking for lazy handshakes
    private var noiseSessionStates: [String: LazyHandshakeState] = [:]
    
+    // MARK: - Cover Traffic
+    
    // Cover traffic for privacy
    private var coverTrafficTimer: Timer?
    private let coverTrafficPrefix = "☂DUMMY☂"  // Prefix to identify dummy messages after decryption
    private var lastCoverTrafficTime = Date()
    
+    // MARK: - Connection State
+    
    // Connection state tracking
    private var peerConnectionStates: [String: PeerConnectionState] = [:]
    private let connectionStateQueue = DispatchQueue(label: "chat.bitchat.connectionState", attributes: .concurrent)
    
+    // MARK: - Protocol ACK Tracking
+    
    // Protocol-level ACK tracking
    private var pendingAcks: [String: (packet: BitchatPacket, timestamp: Date, retries: Int)] = [:]
    private let ackTimeout: TimeInterval = 5.0  // 5 seconds to receive ACK
@@ -421,10 +432,14 @@ class BluetoothMeshService: NSObject {
    private var connectionKeepAliveTimer: Timer?  // Timer to send keepalive pings
    private let keepAliveInterval: TimeInterval = 20.0  // Send keepalive every 20 seconds
    
+    // MARK: - Timing and Delays
+    
    // Timing randomization for privacy (now with exponential distribution)
    private let minMessageDelay: TimeInterval = 0.01  // 10ms minimum for faster sync
    private let maxMessageDelay: TimeInterval = 0.1   // 100ms maximum for faster sync
    
+    // MARK: - RSSI Management
+    
    // Dynamic RSSI threshold based on network size (smart compromise)
    private var dynamicRSSIThreshold: Int {
        let peerCount = activePeers.count
@@ -437,6 +452,8 @@ class BluetoothMeshService: NSObject {
        }
    }
    
+    // MARK: - Fragment Handling
+    
    // Fragment handling with security limits
    private var incomingFragments: [String: [Int: Data]] = [:]  // fragmentID -> [index: data]
    private var fragmentMetadata: [String: (originalType: UInt8, totalFragments: Int, timestamp: Date)] = [:]
@@ -444,9 +461,11 @@ class BluetoothMeshService: NSObject {
    private let maxConcurrentFragmentSessions = 20  // Limit concurrent fragment sessions to prevent DoS
    private let fragmentTimeout: TimeInterval = 30  // 30 seconds timeout for incomplete fragments
    
+    // MARK: - Peer Identity
+    
    var myPeerID: String
    
-    // ===== SCALING OPTIMIZATIONS =====
+    // MARK: - Scaling Optimizations
    
    // Connection pooling
    private var connectionPool: [String: CBPeripheral] = [:]
@@ -457,6 +476,8 @@ class BluetoothMeshService: NSObject {
    private let maxConnectionAttempts = 3
    private let baseBackoffInterval: TimeInterval = 1.0
    
+    // MARK: - Peripheral Mapping
+    
    // Simplified peripheral mapping system
    private struct PeripheralMapping {
        let peripheral: CBPeripheral
@@ -523,20 +544,28 @@ class BluetoothMeshService: NSObject {
        return nil
    }
    
+    // MARK: - Probabilistic Flooding
+    
    // Probabilistic flooding
    private var relayProbability: Double = 1.0  // Start at 100%, decrease with peer count
    private let minRelayProbability: Double = 0.4  // Minimum 40% relay chance - ensures coverage
    
+    // MARK: - Message Aggregation
+    
    // Message aggregation
    private var pendingMessages: [(message: BitchatPacket, destination: String?)] = []
    private var aggregationTimer: Timer?
    private var aggregationWindow: TimeInterval = 0.1  // 100ms window
    private let maxAggregatedMessages = 5
    
+    // MARK: - Bloom Filter
+    
    // Optimized Bloom filter for efficient duplicate detection
    private var messageBloomFilter = OptimizedBloomFilter(expectedItems: 2000, falsePositiveRate: 0.01)
    private var bloomFilterResetTimer: Timer?
    
+    // MARK: - Network Size Estimation
+    
    // Network size estimation
    private var estimatedNetworkSize: Int {
        return max(activePeers.count, connectedPeripherals.count)
@@ -578,11 +607,15 @@ class BluetoothMeshService: NSObject {
        }
    }
    
+    // MARK: - Relay Cancellation
+    
    // Relay cancellation mechanism to prevent duplicate relays
    private var pendingRelays: [String: DispatchWorkItem] = [:]  // messageID -> relay task
    private let pendingRelaysLock = NSLock()
    private let relayCancellationWindow: TimeInterval = 0.05  // 50ms window to detect other relays
    
+    // MARK: - Memory Management
+    
    // Global memory limits to prevent unbounded growth
    private let maxPendingPrivateMessages = 100
    private let maxCachedMessagesSentToPeer = 1000
@@ -593,6 +626,8 @@ class BluetoothMeshService: NSObject {
    private var acknowledgedPackets = Set<String>()
    private let acknowledgedPacketsLock = NSLock()
    
+    // MARK: - Rate Limiting
+    
    // Rate limiting for flood control with separate limits for different message types
    private var messageRateLimiter: [String: [Date]] = [:]  // peerID -> recent message timestamps
    private var protocolMessageRateLimiter: [String: [Date]] = [:]  // peerID -> protocol msg timestamps
@@ -603,11 +638,13 @@ class BluetoothMeshService: NSObject {
    private let maxTotalMessagesPerMinute = 2000  // Increased for legitimate use
    private var totalMessageTimestamps: [Date] = []
    
+    // MARK: - BLE Advertisement
+    
    // BLE advertisement for lightweight presence
    private var advertisementData: [String: Any] = [:]
    private var isAdvertising = false
    
-    // ===== MESSAGE AGGREGATION =====
+    // MARK: - Message Aggregation Implementation
    
    private func startAggregationTimer() {
        aggregationTimer?.invalidate()
@@ -673,12 +710,36 @@ class BluetoothMeshService: NSObject {
    
    // Removed getPublicKeyFingerprint - no longer needed with Noise
    
+    // MARK: - Peer Identity Mapping
+    
    // Get peer's fingerprint (replaces getPeerPublicKey)
    func getPeerFingerprint(_ peerID: String) -> String? {
        return noiseService.getPeerFingerprint(peerID)
    }
    
-    // MARK: - Peer Identity Mapping
+    // Get fingerprint for a peer ID
+    func getFingerprint(for peerID: String) -> String? {
+        return collectionsQueue.sync {
+            peerIDToFingerprint[peerID]
+        }
+    }
+    
+    // Check if a peer ID belongs to us (current or previous)
+    func isPeerIDOurs(_ peerID: String) -> Bool {
+        if peerID == myPeerID {
+            return true
+        }
+        
+        // Check if it's our previous ID within grace period
+        if let previousID = previousPeerID,
+           peerID == previousID,
+           let rotationTime = rotationTimestamp,
+           Date().timeIntervalSince(rotationTime) < rotationGracePeriod {
+            return true
+        }
+        
+        return false
+    }
    
    // Update peer identity binding when receiving announcements
    func updatePeerBinding(_ newPeerID: String, fingerprint: String, binding: PeerIdentityBinding) {
@@ -773,38 +834,69 @@ class BluetoothMeshService: NSObject {
        }
    }
    
-    // Get current peer ID for a fingerprint
-    func getCurrentPeerID(for fingerprint: String) -> String? {
+    // Public method to get current peer ID for a fingerprint
+    func getCurrentPeerIDForFingerprint(_ fingerprint: String) -> String? {
        return collectionsQueue.sync {
-            fingerprintToPeerID[fingerprint]
+            return fingerprintToPeerID[fingerprint]
        }
    }
    
-    // Get fingerprint for a peer ID
-    func getFingerprint(for peerID: String) -> String? {
+    // Public method to get all current peer IDs for known fingerprints
+    func getCurrentPeerIDs() -> [String: String] {
        return collectionsQueue.sync {
-            peerIDToFingerprint[peerID]
+            return fingerprintToPeerID
        }
    }
    
-    // Check if a peer ID belongs to us (current or previous)
-    func isPeerIDOurs(_ peerID: String) -> Bool {
-        if peerID == myPeerID {
-            return true
+    // Notify delegate when peer ID changes
+    private func notifyPeerIDChange(oldPeerID: String, newPeerID: String, fingerprint: String) {
+        DispatchQueue.main.async { [weak self] in
+            // Remove old peer ID from active peers and announcedPeers
+            self?.collectionsQueue.sync(flags: .barrier) {
+                _ = self?.activePeers.remove(oldPeerID)
+                // Don't pre-insert the new peer ID - let the announce packet handle it
+                // This ensures the connect message logic works properly
+            }
+            
+            // Also remove from announcedPeers so the new ID can trigger a connect message
+            self?.announcedPeers.remove(oldPeerID)
+            
+            // Update peer list
+            self?.notifyPeerListUpdate(immediate: true)
+            
+            // Don't send disconnect/connect messages for peer ID rotation
+            // The peer didn't actually disconnect, they just rotated their ID
+            // This prevents confusing messages like "3a7e1c2c0d8943b9 disconnected"
+            
+            // Instead, notify the delegate about the peer ID change if needed
+            // (Could add a new delegate method for this in the future)
+        }
+    }
+    
+    // MARK: - Peer Connection Management
+    
+    func getCachedPublicKey(for peerID: String) -> Data? {
+        return collectionsQueue.sync {
+            // Check if cache entry exists and is not expired
+            if let timestamp = identityCacheTimestamps[peerID],
+               Date().timeIntervalSince(timestamp) < identityCacheTTL {
+                return peerPublicKeyCache[peerID]
+            }
+            return nil
+        }
+    }
+    
+    func getCachedSigningKey(for peerID: String) -> Data? {
+        return collectionsQueue.sync {
+            // Check if cache entry exists and is not expired
+            if let timestamp = identityCacheTimestamps[peerID],
+               Date().timeIntervalSince(timestamp) < identityCacheTTL {
+                return peerSigningKeyCache[peerID]
+            }
+            return nil
        }
-        
-        // Check if it's our previous ID within grace period
-        if let previousID = previousPeerID,
-           peerID == previousID,
-           let rotationTime = rotationTimestamp,
-           Date().timeIntervalSince(rotationTime) < rotationGracePeriod {
-            return true
-        }
-        
-        return false
    }
    
-    // Update peer connection state
    private func updatePeerConnectionState(_ peerID: String, state: PeerConnectionState) {
        connectionStateQueue.async(flags: .barrier) { [weak self] in
            guard let self = self else { return }
@@ -956,6 +1048,8 @@ class BluetoothMeshService: NSObject {
        rotationLocked = false
    }
    
+    // MARK: - Initialization
+    
    override init() {
        // Generate ephemeral peer ID for each session to prevent tracking
        self.myPeerID = ""
@@ -1080,6 +1174,8 @@ class BluetoothMeshService: NSObject {
        #endif
    }
    
+    // MARK: - Deinitialization and Cleanup
+    
    deinit {
        cleanup()
        scanDutyCycleTimer?.invalidate()
@@ -1148,6 +1244,8 @@ class BluetoothMeshService: NSObject {
        lastHeardFromPeer.removeAll()
    }
    
+    // MARK: - Service Management
+    
    func startServices() {
        // Starting services
        // Start both central and peripheral services
@@ -1176,6 +1274,8 @@ class BluetoothMeshService: NSObject {
        }
    }
    
+    // MARK: - Message Sending
+    
    func sendBroadcastAnnounce() {
        guard let vm = delegate as? ChatViewModel else { return }
        
@@ -1370,46 +1470,6 @@ class BluetoothMeshService: NSObject {
        }
    }
    
-    // Public method to get current peer ID for a fingerprint
-    func getCurrentPeerIDForFingerprint(_ fingerprint: String) -> String? {
-        return collectionsQueue.sync {
-            return fingerprintToPeerID[fingerprint]
-        }
-    }
-    
-    // Public method to get all current peer IDs for known fingerprints
-    func getCurrentPeerIDs() -> [String: String] {
-        return collectionsQueue.sync {
-            return fingerprintToPeerID
-        }
-    }
-    
-    // Notify delegate when peer ID changes
-    private func notifyPeerIDChange(oldPeerID: String, newPeerID: String, fingerprint: String) {
-        DispatchQueue.main.async { [weak self] in
-            // Remove old peer ID from active peers and announcedPeers
-            self?.collectionsQueue.sync(flags: .barrier) {
-                _ = self?.activePeers.remove(oldPeerID)
-                // Don't pre-insert the new peer ID - let the announce packet handle it
-                // This ensures the connect message logic works properly
-            }
-            
-            // Also remove from announcedPeers so the new ID can trigger a connect message
-            self?.announcedPeers.remove(oldPeerID)
-            
-            // Update peer list
-            self?.notifyPeerListUpdate(immediate: true)
-            
-            // Don't send disconnect/connect messages for peer ID rotation
-            // The peer didn't actually disconnect, they just rotated their ID
-            // This prevents confusing messages like "3a7e1c2c0d8943b9 disconnected"
-            
-            // Instead, notify the delegate about the peer ID change if needed
-            // (Could add a new delegate method for this in the future)
-        }
-    }
-    
-    
    func sendDeliveryAck(_ ack: DeliveryAck, to recipientID: String) {
        // Use per-peer encryption queue to prevent nonce desynchronization
        let encryptionQueue = getEncryptionQueue(for: recipientID)
@@ -1589,13 +1649,6 @@ class BluetoothMeshService: NSObject {
        broadcastPacket(packet)
    }
    
-    
-    func getPeerNicknames() -> [String: String] {
-        return collectionsQueue.sync {
-            return peerNicknames
-        }
-    }
-    
    // Get Noise session state for UI display
    func getNoiseSessionState(for peerID: String) -> LazyHandshakeState {
        return collectionsQueue.sync {
@@ -1634,6 +1687,12 @@ class BluetoothMeshService: NSObject {
        initiateNoiseHandshake(with: peerID)
    }
    
+    func getPeerNicknames() -> [String: String] {
+        return collectionsQueue.sync {
+            return peerNicknames
+        }
+    }
+    
    func getPeerRSSI() -> [String: NSNumber] {
        var rssiValues = peerRSSI
        
@@ -3602,6 +3661,8 @@ class BluetoothMeshService: NSObject {
 }  // End of BluetoothMeshService class

 extension BluetoothMeshService: CBCentralManagerDelegate {
+    // MARK: - CBCentralManagerDelegate
+    
    func centralManagerDidUpdateState(_ central: CBCentralManager) {
        // Central manager state updated
        switch central.state {
@@ -3968,6 +4029,8 @@ extension BluetoothMeshService: CBCentralManagerDelegate {
 }

 extension BluetoothMeshService: CBPeripheralDelegate {
+    // MARK: - CBPeripheralDelegate
+    
    func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
        if let error = error {
            SecureLogger.log("Error discovering services: \(error)", 
@@ -4146,6 +4209,8 @@ extension BluetoothMeshService: CBPeripheralDelegate {
 }

 extension BluetoothMeshService: CBPeripheralManagerDelegate {
+    // MARK: - CBPeripheralManagerDelegate
+    
    func peripheralManagerDidUpdateState(_ peripheral: CBPeripheralManager) {
        // Peripheral manager state updated
        switch peripheral.state {
@@ -16,10 +16,14 @@ import UIKit
 #endif

 class ChatViewModel: ObservableObject {
+    // MARK: - Published Properties
+    
    @Published var messages: [BitchatMessage] = []
    private let maxMessages = 1337 // Maximum messages before oldest are removed
    @Published var connectedPeers: [String] = []
    
+    // MARK: - Message Batching Properties
+    
    // Message batching for performance
    private var pendingMessages: [BitchatMessage] = []
    private var pendingPrivateMessages: [String: [BitchatMessage]] = [:] // peerID -> messages
@@ -44,6 +48,8 @@ class ChatViewModel: ObservableObject {
    @Published var autocompleteRange: NSRange? = nil
    @Published var selectedAutocompleteIndex: Int = 0
    
+    // MARK: - Autocomplete Properties
+    
    // Autocomplete optimization
    private let mentionRegex = try? NSRegularExpression(pattern: "@([a-zA-Z0-9_]*)$", options: [])
    private var cachedNicknames: [String] = []
@@ -52,18 +58,26 @@ class ChatViewModel: ObservableObject {
    // Temporary property to fix compilation
    @Published var showPasswordPrompt = false
    
+    // MARK: - Services and Storage
+    
    var meshService = BluetoothMeshService()
    private let userDefaults = UserDefaults.standard
    private let nicknameKey = "bitchat.nickname"
    
+    // MARK: - Caches
+    
    // Caches for expensive computations
    private var rssiColorCache: [String: Color] = [:] // key: "\(rssi)_\(isDark)"
    private var encryptionStatusCache: [String: EncryptionStatus] = [:] // key: peerID
    
+    // MARK: - Social Features
+    
    @Published var favoritePeers: Set<String> = []  // Now stores public key fingerprints instead of peer IDs
    private var peerIDToPublicKeyFingerprint: [String: String] = [:]  // Maps ephemeral peer IDs to persistent fingerprints
    private var blockedUsers: Set<String> = []  // Stores public key fingerprints of blocked users
    
+    // MARK: - Encryption and Security
+    
    // Noise Protocol encryption status
    @Published var peerEncryptionStatus: [String: EncryptionStatus] = [:]  // peerID -> encryption status
    @Published var verifiedFingerprints: Set<String> = []  // Set of verified fingerprints
@@ -71,12 +85,16 @@ class ChatViewModel: ObservableObject {
    
    // Messages are naturally ephemeral - no persistent storage
    
+    // MARK: - Message Delivery Tracking
+    
    // Delivery tracking
    private var deliveryTrackerCancellable: AnyCancellable?
    
    // Track sent read receipts to avoid duplicates
    private var sentReadReceipts: Set<String> = []  // messageID set
    
+    // MARK: - Initialization
+    
    init() {
        loadNickname()
        loadFavorites()
@@ -174,6 +192,8 @@ class ChatViewModel: ObservableObject {
        #endif
    }
    
+    // MARK: - Deinitialization
+    
    deinit {
        // Clean up timer
        messageBatchTimer?.invalidate()
@@ -182,6 +202,8 @@ class ChatViewModel: ObservableObject {
        userDefaults.synchronize()
    }
    
+    // MARK: - Nickname Management
+    
    private func loadNickname() {
        if let savedNickname = userDefaults.string(forKey: nicknameKey) {
            // Trim whitespace when loading
@@ -213,6 +235,8 @@ class ChatViewModel: ObservableObject {
        saveNickname()
    }
    
+    // MARK: - Favorites Management
+    
    private func loadFavorites() {
        // Load favorites from secure storage
        favoritePeers = SecureIdentityStateManager.shared.getFavorites()
@@ -223,6 +247,8 @@ class ChatViewModel: ObservableObject {
        // This method is kept for compatibility
    }
    
+    // MARK: - Blocked Users Management
+    
    private func loadBlockedUsers() {
        // Load blocked users from secure storage
        let allIdentities = SecureIdentityStateManager.shared.getAllSocialIdentities()
@@ -275,6 +301,8 @@ class ChatViewModel: ObservableObject {
        return SecureIdentityStateManager.shared.isFavorite(fingerprint: fp)
    }
    
+    // MARK: - Public Key and Identity Management
+    
    // Called when we receive a peer's public key
    func registerPeerPublicKey(peerID: String, publicKeyData: Data) {
        // Create a fingerprint from the public key (full SHA256, not truncated)
@@ -379,6 +407,8 @@ class ChatViewModel: ObservableObject {
        }
    }
    
+    // MARK: - Message Sending
+    
    func sendMessage(_ content: String) {
        guard !content.isEmpty else { return }
        
@@ -479,6 +509,8 @@ class ChatViewModel: ObservableObject {
        meshService.sendPrivateMessage(content, to: peerID, recipientNickname: recipientNickname, messageID: message.id)
    }
    
+    // MARK: - Private Chat Management
+    
    func startPrivateChat(with peerID: String) {
        let peerNickname = meshService.getPeerNicknames()[peerID] ?? "unknown"
        
@@ -581,6 +613,8 @@ class ChatViewModel: ObservableObject {
        selectedPrivateChatFingerprint = nil
    }
    
+    // MARK: - Message Retry Handling
+    
    @objc private func handleRetryMessage(_ notification: Notification) {
        guard let messageID = notification.userInfo?["messageID"] as? String else { return }
        
@@ -605,6 +639,8 @@ class ChatViewModel: ObservableObject {
        }
    }
    
+    // MARK: - App Lifecycle
+    
    @objc private func appDidBecomeActive() {
        // When app becomes active, send read receipts for visible private chat
        if let peerID = selectedPrivateChatPeer {
@@ -798,6 +834,8 @@ class ChatViewModel: ObservableObject {
    }
    
    
+    // MARK: - Emergency Functions
+    
    // PANIC: Emergency data clearing for activist safety
    func panicClearAllData() {
        // Flush any pending messages immediately before clearing
@@ -868,6 +906,8 @@ class ChatViewModel: ObservableObject {
    
    
    
+    // MARK: - Formatting Helpers
+    
    func formatTimestamp(_ date: Date) -> String {
        let formatter = DateFormatter()
        formatter.dateFormat = "HH:mm:ss"
@@ -909,6 +949,8 @@ class ChatViewModel: ObservableObject {
        return color
    }
    
+    // MARK: - Autocomplete
+    
    func updateAutocomplete(for text: String, cursorPosition: Int) {
        // Quick early exit for empty text
        guard cursorPosition > 0 else {
@@ -1001,6 +1043,8 @@ class ChatViewModel: ObservableObject {
        return range.location + nickname.count + 2
    }
    
+    // MARK: - Message Formatting
+    
    func getSenderColor(for message: BitchatMessage, colorScheme: ColorScheme) -> Color {
        let isDark = colorScheme == .dark
        let primaryColor = isDark ? Color.green : Color(red: 0, green: 0.5, blue: 0)
@@ -1390,7 +1434,8 @@ class ChatViewModel: ObservableObject {
        rssiColorCache.removeAll()
    }
    
-    // Trim messages to keep only the most recent maxMessages
+    // MARK: - Message Batching
+    
    private func trimMessagesIfNeeded() {
        if messages.count > maxMessages {
            let removeCount = messages.count - maxMessages
@@ -1398,7 +1443,6 @@ class ChatViewModel: ObservableObject {
        }
    }
    
-    // Trim private chat messages to keep only the most recent maxMessages
    private func trimPrivateChatMessagesIfNeeded(for peerID: String) {
        if let count = privateChats[peerID]?.count, count > maxMessages {
            let removeCount = count - maxMessages
@@ -1406,8 +1450,6 @@ class ChatViewModel: ObservableObject {
        }
    }
    
-    // MARK: - Message Batching
-    
    private func addMessageToBatch(_ message: BitchatMessage) {
        pendingMessages.append(message)
        scheduleBatchFlush()
@@ -1512,6 +1554,8 @@ class ChatViewModel: ObservableObject {
        }
    }
    
+    // MARK: - Fingerprint Management
+    
    func showFingerprint(for peerID: String) {
        showingFingerprintFor = peerID
    }
@@ -1646,48 +1690,14 @@ class ChatViewModel: ObservableObject {
            }
        }
    }
-    
-    func handleHandshakeRequest(from peerID: String, nickname: String, pendingCount: UInt8) {
-        // Create a notification message
-        let notificationMessage = BitchatMessage(
-            sender: "system",
-            content: "📨 \(nickname) wants to send you \(pendingCount) message\(pendingCount == 1 ? "" : "s"). Open the conversation to receive.",
-            timestamp: Date(),
-            isRelay: false,
-            originalSender: nil,
-            isPrivate: false,
-            recipientNickname: nil,
-            senderPeerID: "system",
-            mentions: nil
-        )
-        
-        // Add to messages
-        messages.append(notificationMessage)
-        trimMessagesIfNeeded()
-        
-        // Show system notification
-        if let fingerprint = getFingerprint(for: peerID) {
-            let isFavorite = favoritePeers.contains(fingerprint)
-            if isFavorite {
-                // Send favorite notification
-                NotificationService.shared.sendPrivateMessageNotification(
-                    from: nickname,
-                    message: "\(pendingCount) message\(pendingCount == 1 ? "" : "s") pending",
-                    peerID: peerID
-                )
-            } else {
-                // Send regular notification
-                NotificationService.shared.sendMentionNotification(
-                    from: nickname,
-                    message: "\(pendingCount) message\(pendingCount == 1 ? "" : "s") pending. Open conversation to receive."
-                )
-            }
-        }
-    }
 }

+// MARK: - BitchatDelegate
+
 extension ChatViewModel: BitchatDelegate {
    
+    // MARK: - Command Handling
+    
    private func handleCommand(_ command: String) {
        let parts = command.split(separator: " ")
        guard let cmd = parts.first else { return }
@@ -2042,6 +2052,46 @@ extension ChatViewModel: BitchatDelegate {
        }
    }
    
+    // MARK: - Message Reception
+    
+    func handleHandshakeRequest(from peerID: String, nickname: String, pendingCount: UInt8) {
+        // Create a notification message
+        let notificationMessage = BitchatMessage(
+            sender: "system",
+            content: "📨 \(nickname) wants to send you \(pendingCount) message\(pendingCount == 1 ? "" : "s"). Open the conversation to receive.",
+            timestamp: Date(),
+            isRelay: false,
+            originalSender: nil,
+            isPrivate: false,
+            recipientNickname: nil,
+            senderPeerID: "system",
+            mentions: nil
+        )
+        
+        // Add to messages
+        messages.append(notificationMessage)
+        trimMessagesIfNeeded()
+        
+        // Show system notification
+        if let fingerprint = getFingerprint(for: peerID) {
+            let isFavorite = favoritePeers.contains(fingerprint)
+            if isFavorite {
+                // Send favorite notification
+                NotificationService.shared.sendPrivateMessageNotification(
+                    from: nickname,
+                    message: "\(pendingCount) message\(pendingCount == 1 ? "" : "s") pending",
+                    peerID: peerID
+                )
+            } else {
+                // Send regular notification
+                NotificationService.shared.sendMentionNotification(
+                    from: nickname,
+                    message: "\(pendingCount) message\(pendingCount == 1 ? "" : "s") pending. Open conversation to receive."
+                )
+            }
+        }
+    }
+    
    func didReceiveMessage(_ message: BitchatMessage) {
        
        
@@ -2342,6 +2392,8 @@ extension ChatViewModel: BitchatDelegate {
        #endif
    }
    
+    // MARK: - Peer Connection Events
+    
    func didConnectToPeer(_ peerID: String) {
        isConnected = true
        
@@ -2435,6 +2487,8 @@ extension ChatViewModel: BitchatDelegate {
        }
    }
    
+    // MARK: - Helper Methods
+    
    private func parseMentions(from content: String) -> [String] {
        let pattern = "@([a-zA-Z0-9_]+)"
        let regex = try? NSRegularExpression(pattern: pattern, options: [])
@@ -2461,6 +2515,8 @@ extension ChatViewModel: BitchatDelegate {
        return SecureIdentityStateManager.shared.isFavorite(fingerprint: fingerprint)
    }
    
+    // MARK: - Delivery Tracking
+    
    func didReceiveDeliveryAck(_ ack: DeliveryAck) {
        // Find the message and update its delivery status
        updateMessageDeliveryStatus(ack.originalMessageID, status: .delivered(to: ack.recipientNickname, at: ack.timestamp))
@@ -8,6 +8,8 @@

 import SwiftUI

+// MARK: - Supporting Types
+
 // Pre-computed peer data for performance
 struct PeerDisplayData: Identifiable {
    let id: String
@@ -19,6 +21,8 @@ struct PeerDisplayData: Identifiable {
    let encryptionStatus: EncryptionStatus
 }

+// MARK: - Lazy Link Preview
+
 // Lazy loading wrapper for link previews
 struct LazyLinkPreviewView: View {
    let url: URL
@@ -44,7 +48,11 @@ struct LazyLinkPreviewView: View {
    }
 }

+// MARK: - Main Content View
+
 struct ContentView: View {
+    // MARK: - Properties
+    
    @EnvironmentObject var viewModel: ChatViewModel
    @State private var messageText = ""
    @State private var textFieldSelection: NSRange? = nil
@@ -66,6 +74,8 @@ struct ContentView: View {
    @State private var scrollThrottleTimer: Timer?
    @State private var autocompleteDebounceTimer: Timer?
    
+    // MARK: - Computed Properties
+    
    private var backgroundColor: Color {
        colorScheme == .dark ? Color.black : Color.white
    }
@@ -78,6 +88,8 @@ struct ContentView: View {
        colorScheme == .dark ? Color.green.opacity(0.8) : Color(red: 0, green: 0.5, blue: 0).opacity(0.8)
    }
    
+    // MARK: - Body
+    
    var body: some View {
        GeometryReader { geometry in
            ZStack {
@@ -221,10 +233,13 @@ struct ContentView: View {
        }
    }
    
+    // MARK: - Message List View
+    
    private func messagesView(privatePeer: String?) -> some View {
        ScrollViewReader { proxy in
            ScrollView {
                VStack(alignment: .leading, spacing: 0) {
+                    // Extract messages based on context (private or public chat)
                    let messages: [BitchatMessage] = {
                        if let privatePeer = privatePeer {
                            let msgs = viewModel.getPrivateChatMessages(for: privatePeer)
@@ -355,6 +370,8 @@ struct ContentView: View {
        }
    }
    
+    // MARK: - Input View
+    
    private var inputView: some View {
        VStack(spacing: 0) {
            // @mentions autocomplete
@@ -544,11 +561,15 @@ struct ContentView: View {
        }
    }
    
+    // MARK: - Actions
+    
    private func sendMessage() {
        viewModel.sendMessage(messageText)
        messageText = ""
    }
    
+    // MARK: - Sidebar View
+    
    private var sidebarView: some View {
        HStack(spacing: 0) {
            // Grey vertical bar for visual continuity
@@ -594,6 +615,7 @@ struct ContentView: View {
                                .foregroundColor(secondaryTextColor)
                                .padding(.horizontal)
                        } else {
+                            // Extract peer data for display
                            let peerNicknames = viewModel.meshService.getPeerNicknames()
                            let peerRSSI = viewModel.meshService.getPeerRSSI()
                            let myPeerID = viewModel.meshService.myPeerID
@@ -939,6 +961,8 @@ struct ContentView: View {
    
 }

+// MARK: - Helper Views
+
 // Helper view for rendering message content with clickable hashtags
 struct MessageContentView: View {
    let message: BitchatMessage
@@ -993,6 +1017,8 @@ struct MessageContentView: View {
            .textSelection(.enabled)
    }
    
+    // MARK: - Helper Methods
+    
    private func buildTextSegments() -> [(text: String, type: String)] {
        var segments: [(text: String, type: String)] = []
        let content = message.content
@@ -1052,6 +1078,8 @@ struct DeliveryStatusView: View {
    let status: DeliveryStatus
    let colorScheme: ColorScheme
    
+    // MARK: - Computed Properties
+    
    private var textColor: Color {
        colorScheme == .dark ? Color.green : Color(red: 0, green: 0.5, blue: 0)
    }
@@ -1060,6 +1088,8 @@ struct DeliveryStatusView: View {
        colorScheme == .dark ? Color.green.opacity(0.8) : Color(red: 0, green: 0.5, blue: 0).opacity(0.8)
    }
    
+    // MARK: - Body
+    
    var body: some View {
        switch status {
        case .sending: