Extract BLE and chat architecture policies (#1324)

Co-authored-by: jack <jackjackbits@users.noreply.github.com>
2026-07-26 12:05:20 +00:00 · 2026-06-02 09:01:59 +02:00
parent 193cfdc06a
commit 3eb4f2bd72
46 changed files with 3286 additions and 786 deletions
@@ -0,0 +1,116 @@
+import BitFoundation
+import Foundation
+
+struct BLEAnnouncePreflightAcceptance {
+    let announcement: AnnouncementPacket
+    let derivedPeerID: PeerID
+}
+
+enum BLEAnnouncePreflightRejection: Equatable {
+    case malformed
+    case senderMismatch(derivedPeerID: PeerID)
+    case selfAnnounce
+    case stale(ageSeconds: Double)
+}
+
+enum BLEAnnouncePreflightDecision {
+    case accept(BLEAnnouncePreflightAcceptance)
+    case reject(BLEAnnouncePreflightRejection)
+}
+
+enum BLEAnnouncePreflightPolicy {
+    static func evaluate(
+        packet: BitchatPacket,
+        from peerID: PeerID,
+        localPeerID: PeerID,
+        now: Date
+    ) -> BLEAnnouncePreflightDecision {
+        guard let announcement = AnnouncementPacket.decode(from: packet.payload) else {
+            return .reject(.malformed)
+        }
+
+        let derivedPeerID = PeerID(publicKey: announcement.noisePublicKey)
+        guard derivedPeerID == peerID else {
+            return .reject(.senderMismatch(derivedPeerID: derivedPeerID))
+        }
+
+        guard peerID != localPeerID else {
+            return .reject(.selfAnnounce)
+        }
+
+        guard !BLEPacketFreshnessPolicy.isStale(timestampMilliseconds: packet.timestamp, now: now) else {
+            return .reject(.stale(ageSeconds: BLEPacketFreshnessPolicy.ageSeconds(
+                timestampMilliseconds: packet.timestamp,
+                now: now
+            )))
+        }
+
+        return .accept(BLEAnnouncePreflightAcceptance(
+            announcement: announcement,
+            derivedPeerID: derivedPeerID
+        ))
+    }
+}
+
+enum BLEAnnounceTrustRejection: Equatable {
+    case missingSignature
+    case invalidSignature
+    case keyMismatch
+}
+
+enum BLEAnnounceTrustDecision: Equatable {
+    case verified
+    case reject(BLEAnnounceTrustRejection)
+
+    var isVerified: Bool {
+        self == .verified
+    }
+}
+
+enum BLEAnnounceTrustPolicy {
+    static func evaluate(
+        hasSignature: Bool,
+        signatureValid: Bool,
+        existingNoisePublicKey: Data?,
+        announcedNoisePublicKey: Data
+    ) -> BLEAnnounceTrustDecision {
+        if let existingNoisePublicKey, existingNoisePublicKey != announcedNoisePublicKey {
+            return .reject(.keyMismatch)
+        }
+
+        guard hasSignature else {
+            return .reject(.missingSignature)
+        }
+
+        guard signatureValid else {
+            return .reject(.invalidSignature)
+        }
+
+        return .verified
+    }
+}
+
+struct BLEAnnounceResponsePlan: Equatable {
+    let shouldNotifyPeerConnected: Bool
+    let shouldScheduleInitialSync: Bool
+    let shouldSendAnnounceBack: Bool
+    let shouldScheduleAfterglow: Bool
+}
+
+enum BLEAnnounceResponsePolicy {
+    static func plan(
+        isDirectAnnounce: Bool,
+        isNewPeer: Bool,
+        isReconnectedPeer: Bool,
+        shouldSendAnnounceBack: Bool
+    ) -> BLEAnnounceResponsePlan {
+        let shouldNotifyPeerConnected = isDirectAnnounce && (isNewPeer || isReconnectedPeer)
+
+        return BLEAnnounceResponsePlan(
+            shouldNotifyPeerConnected: shouldNotifyPeerConnected,
+            shouldScheduleInitialSync: shouldNotifyPeerConnected,
+            shouldSendAnnounceBack: shouldSendAnnounceBack,
+            shouldScheduleAfterglow: isNewPeer
+        )
+    }
+}