Extract GeohashParticipantTracker from ChatViewModel

Refactor participant tracking logic into a dedicated, testable class: - Create GeohashParticipantTracker with GeohashParticipantContext protocol - Move GeoPerson struct to new file - Extract participant recording, refresh, and count logic - Add 18 comprehensive tests for the tracker - Update ChatViewModel to use tracker via dependency injection - Subscribe to tracker's objectWillChange for SwiftUI observation This reduces coupling in ChatViewModel and makes participant tracking testable in isolation.
2026-07-25 13:45:20 +00:00 · 2025-11-24 11:34:47 -10:00
parent ce33132a0f
commit f893f0605a
3 changed files with 498 additions and 95 deletions
@@ -92,7 +92,7 @@ import UniformTypeIdentifiers
 /// Manages the application state and business logic for BitChat.
 /// Acts as the primary coordinator between UI components and backend services,
 /// implementing the BitchatDelegate protocol to handle network events.
-final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProvider {
+final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProvider, GeohashParticipantContext {
    // Precompiled regexes and detectors reused across formatting
    private enum Regexes {
        static let hashtag: NSRegularExpression = {
@@ -419,10 +419,8 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
    private var lastPublicActivityAt: [String: Date] = [:]   // channelKey -> last activity time
    private var lastPublicActivityNotifyAt: [String: Date] = [:]
    private let channelInactivityThreshold: TimeInterval = TransportConfig.uiChannelInactivityThresholdSeconds
-    // Geohash participants (per geohash: pubkey -> lastSeen)
-    private var geoParticipants: [String: [String: Date]] = [:]
-    @Published private(set) var geohashPeople: [GeoPerson] = []
-    private var geoParticipantsTimer: Timer? = nil
+    // Geohash participant tracker
+    let participantTracker = GeohashParticipantTracker(activityCutoff: -TransportConfig.uiRecentCutoffFiveMinutesSeconds)
    // Participants who indicated they teleported (by tag in their events)
    @Published private(set) var teleportedGeo: Set<String> = []  // lowercased pubkey hex
    // Sampling subscriptions for multiple geohashes (when channel sheet is open)
@@ -526,6 +524,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        
        // Wire up dependencies
        self.commandProcessor.chatViewModel = self
+        self.participantTracker.configure(context: self)
        
        // Subscribe to privateChatManager changes to trigger UI updates
        privateChatManager.objectWillChange
@@ -533,6 +532,13 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
                self?.objectWillChange.send()
            }
            .store(in: &cancellables)
+
+        // Subscribe to participantTracker changes to trigger UI updates
+        participantTracker.objectWillChange
+            .sink { [weak self] _ in
+                self?.objectWillChange.send()
+            }
+            .store(in: &cancellables)
        self.commandProcessor.meshService = meshService
        
        loadNickname()
@@ -873,7 +879,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
            return
        }
        // Ensure participant decay timer is running
-        startGeoParticipantsTimer()
+        participantTracker.startRefreshTimer()
        // Unsubscribe + resubscribe
        NostrRelayManager.shared.unsubscribe(id: subID)
        let filter = NostrFilter.geohashEphemeral(
@@ -932,7 +938,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        nostrKeyMapping[PeerID(nostr: event.pubkey)] = event.pubkey

        // Update participants last-seen for this pubkey
-        recordGeoParticipant(pubkeyHex: event.pubkey)
+        participantTracker.recordParticipant(pubkeyHex: event.pubkey)
        
        // Track teleported tag (only our format ["t","teleport"]) for icon state
        let hasTeleportTag = event.tags.contains(where: { tag in
@@ -1479,7 +1485,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        }

        // Track ourselves as active participant
-        recordGeoParticipant(pubkeyHex: identity.publicKeyHex)
+        participantTracker.recordParticipant(pubkeyHex: identity.publicKeyHex)
        nostrKeyMapping[PeerID(nostr: identity.publicKeyHex)] = identity.publicKeyHex
        SecureLogger.debug("GeoTeleport: sent geo message pub=\(identity.publicKeyHex.prefix(8))… teleported=\(context.teleported)", category: .session)

@@ -1514,8 +1520,8 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
            if emptyMesh > 0 {
                SecureLogger.debug("RenderGuard: mesh timeline contains \(emptyMesh) empty messages", category: .session)
            }
-            stopGeoParticipantsTimer()
-            geohashPeople = []
+            participantTracker.stopRefreshTimer()
+            participantTracker.setActiveGeohash(nil)
            teleportedGeo.removeAll()
        case .location:
            refreshVisibleMessages(from: channel)
@@ -1536,16 +1542,17 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
            geoDmSubscriptionID = nil
        }
        currentGeohash = nil
+        participantTracker.setActiveGeohash(nil)
        // Reset nickname cache for geochat participants
        geoNicknames.removeAll()
-        geohashPeople = []
-        
+
        guard case .location(let ch) = channel else { return }
        currentGeohash = ch.geohash
+        participantTracker.setActiveGeohash(ch.geohash)
        
        // Ensure self appears immediately in the people list; mark teleported state only when truly teleported
        if let id = try? idBridge.deriveIdentity(forGeohash: ch.geohash) {
-            recordGeoParticipant(pubkeyHex: id.publicKeyHex)
+            participantTracker.recordParticipant(pubkeyHex: id.publicKeyHex)
            let hasRegional = !LocationChannelManager.shared.availableChannels.isEmpty
            let inRegional = LocationChannelManager.shared.availableChannels.contains { $0.geohash == ch.geohash }
            let key = id.publicKeyHex.lowercased()
@@ -1559,7 +1566,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        
        let subID = "geo-\(ch.geohash)"
        geoSubscriptionID = subID
-        startGeoParticipantsTimer()
+        participantTracker.startRefreshTimer()
        let ts = Date().addingTimeInterval(-TransportConfig.nostrGeohashInitialLookbackSeconds)
        let filter = NostrFilter.geohashEphemeral(ch.geohash, since: ts, limit: TransportConfig.nostrGeohashInitialLimit)
        let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
@@ -1629,7 +1636,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        nostrKeyMapping[PeerID(nostr: event.pubkey)] = event.pubkey
        
        // Update participants last-seen for this pubkey
-        recordGeoParticipant(pubkeyHex: event.pubkey)
+        participantTracker.recordParticipant(pubkeyHex: event.pubkey)
        
        let senderName = displayNameForNostrPubkey(event.pubkey)
        let content = event.content
@@ -1811,49 +1818,6 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
    }

    // MARK: - Geohash Participants
-    struct GeoPerson: Identifiable, Equatable {
-        let id: String        // pubkey hex (lowercased)
-        let displayName: String
-        let lastSeen: Date
-    }
-
-    private func recordGeoParticipant(pubkeyHex: String) {
-        guard let gh = currentGeohash else { return }
-        let key = pubkeyHex.lowercased()
-        var map = geoParticipants[gh] ?? [:]
-        map[key] = Date()
-        geoParticipants[gh] = map
-        refreshGeohashPeople()
-    }
-
-    private func recordGeoParticipant(pubkeyHex: String, geohash: String) {
-        let key = pubkeyHex.lowercased()
-        var map = geoParticipants[geohash] ?? [:]
-        map[key] = Date()
-        geoParticipants[geohash] = map
-        // Only refresh list if this geohash is currently selected
-        if currentGeohash == geohash {
-            refreshGeohashPeople()
-        }
-    }
-
-    private func refreshGeohashPeople() {
-        guard let gh = currentGeohash else { geohashPeople = []; return }
-        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
-        var map = geoParticipants[gh] ?? [:]
-        // Prune expired entries
-        map = map.filter { $0.value >= cutoff }
-        // Remove blocked Nostr pubkeys
-        map = map.filter { !identityManager.isNostrBlocked(pubkeyHexLowercased: $0.key) }
-        geoParticipants[gh] = map
-        // Build display list
-        let people = map
-            .map { (pub, seen) in
-                GeoPerson(id: pub, displayName: displayNameForNostrPubkey(pub), lastSeen: seen)
-            }
-            .sorted { $0.lastSeen > $1.lastSeen }
-        geohashPeople = people
-    }

    @MainActor
    func isSelfSender(peerID: PeerID?, displayName: String?) -> Bool {
@@ -1878,33 +1842,17 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
        return false
    }

-    private func startGeoParticipantsTimer() {
-        stopGeoParticipantsTimer()
-        geoParticipantsTimer = Timer.scheduledTimer(withTimeInterval: 30.0, repeats: true) { [weak self] _ in
-            Task { @MainActor in
-                self?.refreshGeohashPeople()
-            }
-        }
+    // MARK: - Public helpers
+
+    /// Published geohash people list for SwiftUI observation
+    var geohashPeople: [GeoPerson] {
+        participantTracker.visiblePeople
    }

-    private func stopGeoParticipantsTimer() {
-        geoParticipantsTimer?.invalidate()
-        geoParticipantsTimer = nil
-    }
-    
-    // MARK: - Public helpers
    /// Return the current, pruned, sorted people list for the active geohash without mutating state.
    @MainActor
    func visibleGeohashPeople() -> [GeoPerson] {
-        guard let gh = currentGeohash else { return [] }
-        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
-        let map = (geoParticipants[gh] ?? [:])
-            .filter { $0.value >= cutoff }
-            .filter { !identityManager.isNostrBlocked(pubkeyHexLowercased: $0.key) }
-        let people = map
-            .map { (pub, seen) in GeoPerson(id: pub, displayName: displayNameForNostrPubkey(pub), lastSeen: seen) }
-            .sorted { $0.lastSeen > $1.lastSeen }
-        return people
+        participantTracker.getVisiblePeople()
    }

    /// CommandContextProvider conformance - returns visible geo participants
@@ -1914,9 +1862,17 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
    /// Returns the current participant count for a specific geohash, using the 5-minute activity window.
    @MainActor
    func geohashParticipantCount(for geohash: String) -> Int {
-        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
-        let map = geoParticipants[geohash] ?? [:]
-        return map.values.filter { $0 >= cutoff }.count
+        participantTracker.participantCount(for: geohash)
+    }
+
+    // MARK: - GeohashParticipantContext Protocol
+
+    func displayNameForPubkey(_ pubkeyHex: String) -> String {
+        displayNameForNostrPubkey(pubkeyHex)
+    }
+
+    func isBlocked(_ pubkeyHexLowercased: String) -> Bool {
+        identityManager.isNostrBlocked(pubkeyHexLowercased: pubkeyHexLowercased)
    }

    // Geohash block helpers
@@ -1928,13 +1884,9 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
    func blockGeohashUser(pubkeyHexLowercased: String, displayName: String) {
        let hex = pubkeyHexLowercased.lowercased()
        identityManager.setNostrBlocked(hex, isBlocked: true)
-        
+
        // Remove from participants for all geohashes
-        for (gh, var map) in geoParticipants {
-            map.removeValue(forKey: hex)
-            geoParticipants[gh] = map
-        }
-        refreshGeohashPeople()
+        participantTracker.removeParticipant(pubkeyHex: hex)
        
        // Remove their public messages from current geohash timeline and visible list
        if let gh = currentGeohash {
@@ -2022,13 +1974,12 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
    
    private func subscribeNostrEvent(_ event: NostrEvent, gh: String) {
        guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
-        
+
        // Compute current participant count (5-minute window) BEFORE updating with this event
-        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
-        let existingCount = geoParticipants[gh]?.values.filter { $0 >= cutoff }.count ?? 0
-        
+        let existingCount = participantTracker.participantCount(for: gh)
+
        // Update participants for this specific geohash
-        recordGeoParticipant(pubkeyHex: event.pubkey, geohash: gh)
+        participantTracker.recordParticipant(pubkeyHex: event.pubkey, geohash: gh)
        
        // Notify only on rising-edge: previously zero people, now someone sends a chat
        let content = event.content.trimmingCharacters(in: .whitespacesAndNewlines)
@@ -3229,7 +3180,7 @@ final class ChatViewModel: ObservableObject, BitchatDelegate, CommandContextProv
                            NostrRelayManager.shared.sendEvent(event, to: targetRelays)
                        }
                        // Track ourselves as active participant
-                        self.recordGeoParticipant(pubkeyHex: identity.publicKeyHex)
+                        self.participantTracker.recordParticipant(pubkeyHex: identity.publicKeyHex)
                    } catch {
                        SecureLogger.error("❌ Failed to send geohash screenshot message: \(error)", category: .session)
                        self.addSystemMessage(