Three bugs were stacking up to make session resume drop the saved offset
for streamed Qobuz tracks:
1. Position save was debounced, not throttled. Each playback tick reset
the 5s timer, so the save never fired while a track played
continuously — the persisted position froze at whatever value got
written during the first quiet window after track start (typically
~2s). Switch to throttle: fire the first call immediately, then once
per 5s window, with a tail call to flush the latest value when the
window ends.
2. togglePlay tried to apply the restore offset via a separate cmdSeek
right after cmdPlayTrack. For Qobuz streaming the audio thread's
Seek handler bails when current_audio_data is unset — streaming
uses current_streaming_source instead — so the seek was silently
dropped and the track started at 0:00. Pass start_position_secs
directly to v2_play_track. The streaming backend (legacy + V2
player) waits for enough buffer to cover the offset plus 8s
headroom, then eagerly decode-and-discards decoder output up to
the offset before engaging the audio engine — no race, no
first-pull underrun. Plex and local tracks keep the old play+seek
path; they load full audio_data so Seek works as-is.
3. The seekbar showed 0:00 from app launch until the user hit play,
even when a saved position was queued. setPendingSessionRestore
now pre-positions currentTime when positionSecs > 0 so the UI
reflects "paused at X" the moment the app opens.
Other plumbing:
- AudioCommand::PlayStreaming carries start_position_secs and
content_length (used to estimate bytes-per-second for the resume
buffer target).
- Player::play_streaming{,_dynamic} grow a start_position_secs
parameter; QConnect and api_server callers pass 0 (remote-driven
playback always starts fresh).
- cmdPlayTrack forwards startPositionSecs as a 5th optional arg.
cc
vicrodh
921f8e1a49