From 8f89279fa47bc07e9350466ba812942af6f24e62 Mon Sep 17 00:00:00 2001
From: Bryan Van Deusen <bryan.vandeusen@fabledsword.com>
Date: Wed, 3 Jun 2026 23:36:43 -0400
Subject: [PATCH] fix(android): UPnP survives screen-off + cursor catches up to
 Sonos

---
 .../player/MinstrelForwardingPlayer.kt        | 40 ++++++++++++++-----
 .../minstrel/player/RemotePlayerState.kt      |  7 +++-
 2 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/android/app/src/main/java/com/fabledsword/minstrel/player/MinstrelForwardingPlayer.kt b/android/app/src/main/java/com/fabledsword/minstrel/player/MinstrelForwardingPlayer.kt
index db857765..cc2e74ae 100644
--- a/android/app/src/main/java/com/fabledsword/minstrel/player/MinstrelForwardingPlayer.kt
+++ b/android/app/src/main/java/com/fabledsword/minstrel/player/MinstrelForwardingPlayer.kt
@@ -264,16 +264,19 @@ class MinstrelForwardingPlayer(
     }
 
     /**
-     * One poll tick: read position + transport state from Sonos and apply to
-     * [remoteState]. The local cursor is NOT synced to Sonos's Track index --
-     * during the 17-second queue load Sonos reports Track=1 (the first added
-     * track) which would silently walk the local cursor to 0, then SetAV+Seek
-     * lands and Sonos jumps to the user's actual track, racing with the
-     * sync. Local + Sonos cursors stay in sync because every override
-     * (seekToNext/Prev/seekTo) advances both sides by the same delta.
-     * Hardware-button or Sonos-app driven advances ARE missed until the
-     * user takes a transport action -- accepted tradeoff pending GENA
-     * event subscriptions.
+     * One poll tick: read position + transport state from Sonos, apply to
+     * [remoteState], and forward-sync the local cursor to Sonos's Track
+     * index when not in queue load.
+     *
+     * Cursor sync is gated on `holder.target == null` (= not loading)
+     * because during load Sonos reports Track=1 while we're still
+     * appending, and syncing would race the SetAV+Seek that lands
+     * after. Outside load, forward sync catches Sonos auto-advances
+     * (queue end-of-track), Sonos-app driven Next presses, and any
+     * drift after a brief poll-failure burst that didn't trip the
+     * drop threshold. Forward-only because a Next override we just
+     * issued can race with a poll still reporting the prior Track --
+     * the next poll catches up safely.
      */
     private suspend fun pollOnce(active: ActiveUpnp) {
         val info = active.avTransport.getPositionInfo()
@@ -283,6 +286,7 @@ class MinstrelForwardingPlayer(
             trackUri = info.trackUri,
             trackNumber = info.track,
         )
+        maybeSyncLocalCursor(info.track)
         val transport = active.avTransport.getTransportInfo()
         when (transport.state) {
             TransportState.PLAYING -> {
@@ -305,6 +309,22 @@ class MinstrelForwardingPlayer(
         }
     }
 
+    private fun maybeSyncLocalCursor(sonosTrack: Int) {
+        if (holder.target.value != null) return
+        if (sonosTrack <= 0) return
+        val sonosIdx = sonosTrack - 1
+        handler.post {
+            val localIdx = delegate.currentMediaItemIndex
+            if (sonosIdx > localIdx && sonosIdx < delegate.mediaItemCount) {
+                Timber.w(
+                    "UPnP cursor catch-up: local=%d -> sonos=%d",
+                    localIdx, sonosIdx,
+                )
+                delegate.seekTo(sonosIdx, 0L)
+            }
+        }
+    }
+
     private companion object {
         const val POLL_INTERVAL_MS = 1_000L
         const val NON_PLAYING_CONFIRM = 2
diff --git a/android/app/src/main/java/com/fabledsword/minstrel/player/RemotePlayerState.kt b/android/app/src/main/java/com/fabledsword/minstrel/player/RemotePlayerState.kt
index 40afc914..fdbd5fcc 100644
--- a/android/app/src/main/java/com/fabledsword/minstrel/player/RemotePlayerState.kt
+++ b/android/app/src/main/java/com/fabledsword/minstrel/player/RemotePlayerState.kt
@@ -67,6 +67,11 @@ class RemotePlayerState @Inject constructor() {
     }
 
     private companion object {
-        const val DROP_THRESHOLD = 3
+        // ~30 seconds of consecutive poll failures before declaring the route
+        // dropped. Bumped from 3 because screen-off WiFi sleep / brief Doze
+        // can stall socket I/O for several seconds without the renderer
+        // actually being unreachable -- a 3-failure drop kicked us back to
+        // local audio every time the phone went into a pocket.
+        const val DROP_THRESHOLD = 30
     }
 }