Mesh robustness optimizations (#463)

* Mesh robustness: link-aware fragmentation, relay jitter, connection budget, adaptive scanning; fix BLE queue deadlock - Link-aware fragmentation using per-link write/notify limits - Directed fragments for one-to-one; exclude from relays - Add relay jitter with cancel-on-duplicate to reduce floods - Cap central links and rate-limit connect attempts with queue - Foreground duty-cycled scanning when connected; continuous when isolated - Fix deadlock by avoiding sync on BLE queue when already on it - Silence Keychain var->let warnings * Mesh: add relay jitter; dynamic RSSI threshold; candidate scoring/backoff; fix misplaced lines in BLEService extension * macOS UI: restore mesh peer list when geohash feature is iOS-only by moving mesh list outside iOS switch (ContentView) * ContentView: add macOS mesh peer list under #else to fix missing People section on macOS * Refactor People section: extract MeshPeerList and GeohashPeopleList into separate views to reduce SwiftUI type-checking complexity; integrate in ContentView * BLE: prevent re-fragmentation loops; UI: darker mesh blue + first-row spacing in peer list * Mesh flood/battery: probabilistic relays, adaptive TTL caps, fragment pacing + scan pause, assembly cap; enable relayed DMs with direct-first then flood fallback. * Refactor BLEService broadcast: split pad policy, encrypted/direct-first handler, and link-aware sender; simplify broadcastPacket to delegate by type. * Extract relay decision into RelayController with RelayDecision; simplify handleReceivedPacket to use it. * Move RelayController and RelayDecision into their own file under Services; keep BLEService leaner. * UI: adjust mesh blue to a darker, less purple tone; apply consistently for count and #mesh badge. * Project: include RelayController.swift in target and sync project file changes. --------- Co-authored-by: jack <jackjackbits@users.noreply.github.com>
2026-07-25 18:25:19 +00:00 · 2025-08-20 16:27:49 +02:00
parent 3074fa0fcb
commit 496972dcc9
8 changed files with 755 additions and 398 deletions
@@ -0,0 +1,47 @@
+import Foundation
+
+// RelayDecision encapsulates a single relay scheduling choice.
+struct RelayDecision {
+    let shouldRelay: Bool
+    let newTTL: UInt8
+    let delayMs: Int
+}
+
+// RelayController centralizes flood control policy for relays.
+struct RelayController {
+    static func decide(ttl: UInt8,
+                       senderIsSelf: Bool,
+                       isEncrypted: Bool,
+                       isDirectedFragment: Bool,
+                       isHandshake: Bool,
+                       degree: Int,
+                       highDegreeThreshold: Int) -> RelayDecision {
+        // Suppress obvious non-relays
+        if ttl <= 1 || senderIsSelf { return RelayDecision(shouldRelay: false, newTTL: ttl, delayMs: 0) }
+
+        // Degree-aware probability to reduce floods in dense graphs
+        let baseProb: Double
+        switch degree {
+        case 0...2: baseProb = 1.0
+        case 3...4: baseProb = 0.9
+        case 5...6: baseProb = 0.7
+        case 7...9: baseProb = 0.55
+        default:    baseProb = 0.45
+        }
+        var prob = baseProb
+        if isHandshake { prob = max(0.3, baseProb - 0.2) }
+
+        // Sample a forwarding decision
+        let shouldRelay = Double.random(in: 0...1) <= prob
+
+        // TTL clamping in dense graphs
+        let ttlCap: UInt8 = degree >= highDegreeThreshold ? 3 : 5
+        let clamped = max(1, min(ttl, ttlCap))
+        let newTTL = clamped &- 1
+
+        // Short jitter to desynchronize rebroadcasts
+        let delayMs = Int.random(in: 20...80)
+        return RelayDecision(shouldRelay: shouldRelay, newTTL: newTTL, delayMs: delayMs)
+    }
+}
+