refactor(nostr): add NostrInboxService and route geohash/DM subscriptions through it; move de-dup away from ChatViewModel

- Introduce Services/NostrInboxService to centralize subscribe/unsubscribe + event de-dup.\n- Wire ChatViewModel resubscribeCurrentGeohash, switchLocationChannel, sampling, and global DM subscribe to use the service.\n- Remove ChatViewModel's local processedNostrEvents tracking.

bitchat.xcodeproj/project.pbxproj

@@ -58,6 +58,8 @@
 		049BD3B52E51F319001A566B /* MessageRouter.swift in Sources */ = {isa = PBXBuildFile; fileRef = 049BD3B02E51F319001A566B /* MessageRouter.swift */; };
 		ABCD00022E5CCCC300162C4A /* ReadReceiptTracker.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABCD00012E5CCCC300162C4A /* ReadReceiptTracker.swift */; };
 		ABCD00032E5CCCC300162C4A /* ReadReceiptTracker.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABCD00012E5CCCC300162C4A /* ReadReceiptTracker.swift */; };
+		ABCD00052E5CCCC300162C4C /* NostrInboxService.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABCD00042E5CCCC300162C4C /* NostrInboxService.swift */; };
+		ABCD00062E5CCCC300162C4D /* NostrInboxService.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABCD00042E5CCCC300162C4C /* NostrInboxService.swift */; };
 		0AE840940F21AFC07C226636 /* PrivateChatE2ETests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8A262EDDC04B7D7B5E31F321 /* PrivateChatE2ETests.swift */; };
 		0B6F25559A21F8C69C8357C6 /* BinaryProtocolTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0B3CC6FA298729906109F61B /* BinaryProtocolTests.swift */; };
 		10E68BB889356219189E38EC /* BitchatApp.swift in Sources */ = {isa = PBXBuildFile; fileRef = EF625BB3AD919322C01A46B2 /* BitchatApp.swift */; };
@@ -216,6 +218,7 @@
 		049BD39F2E51DBF4001A566B /* PeerID.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PeerID.swift; sourceTree = "<group>"; };
 		049BD3A42E51DC0E001A566B /* MessageDeduplicator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageDeduplicator.swift; sourceTree = "<group>"; };
 		ABCD00012E5CCCC300162C4A /* ReadReceiptTracker.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ReadReceiptTracker.swift; sourceTree = "<group>"; };
+		ABCD00042E5CCCC300162C4C /* NostrInboxService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NostrInboxService.swift; sourceTree = "<group>"; };
 		049BD3AA2E51E38E001A566B /* PeerIDResolver.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PeerIDResolver.swift; sourceTree = "<group>"; };
 		049BD3AD2E51ED60001A566B /* Transport.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Transport.swift; sourceTree = "<group>"; };
 		049BD3B02E51F319001A566B /* MessageRouter.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageRouter.swift; sourceTree = "<group>"; };
@@ -524,6 +527,7 @@
 			children = (
 				048A4BE62E5CCCC300162C4A /* TransportConfig.swift */,
 				ABCD00012E5CCCC300162C4A /* ReadReceiptTracker.swift */,
+				ABCD00042E5CCCC300162C4C /* NostrInboxService.swift */,
 				AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */,
 				047502B82E560F690083520F /* RelayController.swift */,
 				0475028B2E54171C0083520F /* LocationChannelManager.swift */,
@@ -748,6 +752,7 @@
 			files = (
                 048A4BE72E5CCCC300162C4A /* TransportConfig.swift in Sources */,
                 ABCD00022E5CCCC300162C4A /* ReadReceiptTracker.swift in Sources */,
+                ABCD00052E5CCCC300162C4C /* NostrInboxService.swift in Sources */,
                 1234567890ABCDEFFEDCBA13 /* PeerDisplayNameResolver.swift in Sources */,
 				AA77BB12CC22DD33EE44FF56 /* VerificationService.swift in Sources */,
 				AA77BB15CC22DD33EE44FF59 /* VerificationViews.swift in Sources */,
@@ -808,6 +813,7 @@
 			files = (
                 048A4BE82E5CCCC300162C4A /* TransportConfig.swift in Sources */,
                 ABCD00032E5CCCC300162C4A /* ReadReceiptTracker.swift in Sources */,
+                ABCD00062E5CCCC300162C4D /* NostrInboxService.swift in Sources */,
                 1234567890ABCDEFFEDCBA14 /* PeerDisplayNameResolver.swift in Sources */,
 				AA77BB11CC22DD33EE44FF55 /* VerificationService.swift in Sources */,
 				AA77BB14CC22DD33EE44FF58 /* VerificationViews.swift in Sources */,

bitchat/Services/NostrInboxService.swift

@@ -0,0 +1,90 @@
+//
+// NostrInboxService.swift
+// bitchat
+//
+// Centralizes Nostr subscribe/unsubscribe and event de-duplication for inbox flows.
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+
+final class NostrInboxService {
+    private var processedIDs: Set<String> = []
+    private var order: [String] = []
+    private let cap: Int
+
+    init(capacity: Int = TransportConfig.uiProcessedNostrEventsCap) {
+        self.cap = capacity
+    }
+
+    private func track(_ id: String) -> Bool {
+        if processedIDs.contains(id) { return false }
+        processedIDs.insert(id)
+        order.append(id)
+        if order.count > cap {
+            let overflow = order.count - cap
+            for _ in 0..<overflow {
+                if let oldest = order.first {
+                    order.removeFirst()
+                    processedIDs.remove(oldest)
+                }
+            }
+        }
+        return true
+    }
+
+    func reset() {
+        processedIDs.removeAll()
+        order.removeAll()
+    }
+
+    // Subscribe to public geohash ephemeral events (kind 20000)
+    @discardableResult
+    func subscribeGeohashEphemeral(
+        geohash: String,
+        lookbackSeconds: TimeInterval,
+        limit: Int,
+        relayCount: Int,
+        subID: String? = nil,
+        handler: @escaping (NostrProtocol.Event) -> Void
+    ) -> String {
+        let id = subID ?? "geo-\(geohash)"
+        let filter = NostrFilter.geohashEphemeral(
+            geohash,
+            since: Date().addingTimeInterval(-lookbackSeconds),
+            limit: limit
+        )
+        let relays = GeoRelayDirectory.shared.closestRelays(toGeohash: geohash, count: relayCount)
+        NostrRelayManager.shared.subscribe(filter: filter, id: id, relayUrls: relays) { [weak self] event in
+            guard let self = self else { return }
+            guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
+            guard self.track(event.id) else { return }
+            handler(event)
+        }
+        return id
+    }
+
+    // Subscribe to gift wraps (DMs) for a given pubkey
+    @discardableResult
+    func subscribeGiftWrapsFor(
+        pubkeyHex: String,
+        lookbackSeconds: TimeInterval,
+        subID: String? = nil,
+        handler: @escaping (NostrProtocol.Event) -> Void
+    ) -> String {
+        let id = subID ?? "dm-\(pubkeyHex.prefix(8))"
+        let filter = NostrFilter.giftWrapsFor(pubkey: pubkeyHex, since: Date().addingTimeInterval(-lookbackSeconds))
+        NostrRelayManager.shared.subscribe(filter: filter, id: id) { [weak self] event in
+            guard let self = self else { return }
+            guard self.track(event.id) else { return }
+            handler(event)
+        }
+        return id
+    }
+
+    func unsubscribe(id: String) {
+        NostrRelayManager.shared.unsubscribe(id: id)
+    }
+}
+

bitchat/ViewModels/ChatViewModel.swift

@@ -348,9 +348,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     var meshService: Transport = BLEService()
     private var nostrRelayManager: NostrRelayManager?
     // PeerManager replaced by UnifiedPeerService
-    private var processedNostrEvents = Set<String>()  // Simple deduplication
+    // NostrInboxService handles event de-duplication
-    private var processedNostrEventOrder: [String] = []
-    private let maxProcessedNostrEvents = TransportConfig.uiProcessedNostrEventsCap
     private let userDefaults = UserDefaults.standard
     private let nicknameKey = "bitchat.nickname"
     // Location channel state (macOS supports manual geohash selection)
@@ -359,6 +357,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     private var geoDmSubscriptionID: String? = nil
     private var currentGeohash: String? = nil
     private var geoNicknames: [String: String] = [:] // pubkeyHex(lowercased) -> nickname
+    private let nostrInbox = NostrInboxService()
     
     // MARK: - Caches
     
@@ -901,20 +900,15 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         startGeoParticipantsTimer()
         // Unsubscribe + resubscribe
         NostrRelayManager.shared.unsubscribe(id: subID)
-        let filter = NostrFilter.geohashEphemeral(
+        nostrInbox.subscribeGeohashEphemeral(
-            ch.geohash,
+            geohash: ch.geohash,
-            since: Date().addingTimeInterval(-TransportConfig.nostrGeohashInitialLookbackSeconds),
+            lookbackSeconds: TransportConfig.nostrGeohashInitialLookbackSeconds,
-            limit: TransportConfig.nostrGeohashInitialLimit
+            limit: TransportConfig.nostrGeohashInitialLimit,
-        )
+            relayCount: TransportConfig.nostrGeoRelayCount,
-        let subRelays = GeoRelayDirectory.shared.closestRelays(
+            subID: subID
-            toGeohash: ch.geohash,
+        ) { [weak self] event in
-            count: TransportConfig.nostrGeoRelayCount
-        )
-        NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
             guard let self = self else { return }
             guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
-            if self.processedNostrEvents.contains(event.id) { return }
-            self.processedNostrEvents.insert(event.id)
             if let gh = self.currentGeohash,
                let myGeoIdentity = try? NostrIdentityBridge.deriveIdentity(forGeohash: gh),
                myGeoIdentity.publicKeyHex.lowercased() == event.pubkey.lowercased() {
@@ -971,11 +965,12 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             let id = try NostrIdentityBridge.deriveIdentity(forGeohash: ch.geohash)
             let dmSub = "geo-dm-\(ch.geohash)"
             geoDmSubscriptionID = dmSub
-            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds))
+            nostrInbox.subscribeGiftWrapsFor(
-            NostrRelayManager.shared.subscribe(filter: dmFilter, id: dmSub) { [weak self] giftWrap in
+                pubkeyHex: id.publicKeyHex,
+                lookbackSeconds: TransportConfig.nostrDMSubscribeLookbackSeconds,
+                subID: dmSub
+            ) { [weak self] giftWrap in
                 guard let self = self else { return }
-                if self.processedNostrEvents.contains(giftWrap.id) { return }
-                self.recordProcessedEvent(giftWrap.id)
                 guard let (content, senderPubkey, rumorTs) = try? NostrProtocol.decryptPrivateMessage(giftWrap: giftWrap, recipientIdentity: id) else { return }
                 guard content.hasPrefix("bitchat1:") else { return }
                 guard let packetData = Self.base64URLDecode(String(content.dropFirst("bitchat1:".count))),
@@ -1512,8 +1507,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         publicBuffer.removeAll(keepingCapacity: false)
         activeChannel = channel
         // Reset deduplication set and optionally hydrate timeline for mesh
-        processedNostrEvents.removeAll()
+        nostrInbox.reset()
-        processedNostrEventOrder.removeAll()
         switch channel {
         case .mesh:
             messages = meshTimeline
@@ -1557,19 +1551,16 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         let subID = "geo-\(ch.geohash)"
         geoSubscriptionID = subID
         startGeoParticipantsTimer()
-        let filter = NostrFilter.geohashEphemeral(
+        nostrInbox.subscribeGeohashEphemeral(
-            ch.geohash,
+            geohash: ch.geohash,
-            since: Date().addingTimeInterval(-TransportConfig.nostrGeohashInitialLookbackSeconds),
+            lookbackSeconds: TransportConfig.nostrGeohashInitialLookbackSeconds,
-            limit: TransportConfig.nostrGeohashInitialLimit
+            limit: TransportConfig.nostrGeohashInitialLimit,
-        )
+            relayCount: TransportConfig.nostrGeoRelayCount,
-        let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
+            subID: subID
-        NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
+        ) { [weak self] event in
             guard let self = self else { return }
             // Only handle ephemeral kind 20000 with matching tag
             guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
-            // Deduplicate
-            if self.processedNostrEvents.contains(event.id) { return }
-            self.recordProcessedEvent(event.id)
             // Log incoming tags for diagnostics
             let tagSummary = event.tags.map { "[" + $0.joined(separator: ",") + "]" }.joined(separator: ",")
             SecureLogger.log("GeoTeleport: recv pub=\(event.pubkey.prefix(8))… tags=\(tagSummary)",
@@ -1646,12 +1637,8 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             // pared back logging: subscribe debug only
             SecureLogger.log("GeoDM: subscribing DMs pub=\(id.publicKeyHex.prefix(8))… sub=\(dmSub)",
                             category: SecureLogger.session, level: .debug)
-            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds))
+            nostrInbox.subscribeGiftWrapsFor(pubkeyHex: id.publicKeyHex, lookbackSeconds: TransportConfig.nostrDMSubscribeLookbackSeconds, subID: dmSub) { [weak self] giftWrap in
-            NostrRelayManager.shared.subscribe(filter: dmFilter, id: dmSub) { [weak self] giftWrap in
                 guard let self = self else { return }
-                // Dedup basic
-                if self.processedNostrEvents.contains(giftWrap.id) { return }
-                self.recordProcessedEvent(giftWrap.id)
                 // Decrypt with per-geohash identity
                 guard let (content, senderPubkey, rumorTs) = try? NostrProtocol.decryptPrivateMessage(giftWrap: giftWrap, recipientIdentity: id) else {
                     SecureLogger.log("GeoDM: failed decrypt giftWrap id=\(giftWrap.id.prefix(8))…",
@@ -1918,7 +1905,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
 
         //
         for (subID, gh) in geoSamplingSubs where toRemove.contains(gh) {
-            NostrRelayManager.shared.unsubscribe(id: subID)
+            nostrInbox.unsubscribe(id: subID)
             geoSamplingSubs.removeValue(forKey: subID)
         }
 
@@ -1926,13 +1913,13 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         for gh in toAdd {
             let subID = "geo-sample-\(gh)"
             geoSamplingSubs[subID] = gh
-            let filter = NostrFilter.geohashEphemeral(
+            nostrInbox.subscribeGeohashEphemeral(
-                gh,
+                geohash: gh,
-                since: Date().addingTimeInterval(-TransportConfig.nostrGeohashSampleLookbackSeconds),
+                lookbackSeconds: TransportConfig.nostrGeohashSampleLookbackSeconds,
-                limit: TransportConfig.nostrGeohashSampleLimit
+                limit: TransportConfig.nostrGeohashSampleLimit,
-            )
+                relayCount: TransportConfig.nostrGeoRelayCount,
-            let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: gh, count: 5)
+                subID: subID
-            NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
+            ) { [weak self] event in
                 guard let self = self else { return }
                 guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
                 // Update participants for this specific geohash
@@ -2008,19 +1995,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     }
 
     // Dedup helper with small memory cap
-    private func recordProcessedEvent(_ id: String) {
+    private func recordProcessedEvent(_ id: String) {}
-        processedNostrEvents.insert(id)
-        processedNostrEventOrder.append(id)
-        if processedNostrEventOrder.count > maxProcessedNostrEvents {
-            let overflow = processedNostrEventOrder.count - maxProcessedNostrEvents
-            for _ in 0..<overflow {
-                if let old = processedNostrEventOrder.first {
-                    processedNostrEventOrder.removeFirst()
-                    processedNostrEvents.remove(old)
-                }
-            }
-        }
-    }
     
     /// Sends an encrypted private message to a specific peer.
     /// - Parameters:
@@ -4939,12 +4914,11 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                         category: SecureLogger.session, level: .debug)
         
         // Subscribe to Nostr messages
-        let filter = NostrFilter.giftWrapsFor(
+        let _ = nostrInbox.subscribeGiftWrapsFor(
-            pubkey: currentIdentity.publicKeyHex,
+            pubkeyHex: currentIdentity.publicKeyHex,
-            since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds)  // Last 24 hours
+            lookbackSeconds: TransportConfig.nostrDMSubscribeLookbackSeconds,
-        )
+            subID: "chat-messages"
-        
+        ) { [weak self] event in
-        nostrRelayManager?.subscribe(filter: filter, id: "chat-messages") { [weak self] event in
             Task { @MainActor in
                 self?.handleNostrMessage(event)
             }
@@ -4953,9 +4927,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     
     @MainActor
     private func handleNostrMessage(_ giftWrap: NostrEvent) {
-        // Simple deduplication
+        // De-duplication handled by NostrInboxService
-        if processedNostrEvents.contains(giftWrap.id) { return }
-        processedNostrEvents.insert(giftWrap.id)
         
         // Client-side filtering: ignore messages older than 24 hours
         // Add 15 minutes buffer since gift wrap timestamps are randomized ±15 minutes