The boot refresh blocked the UI for up to 195ms per sync block with 10
large feeds (500 episodes × 10KB descriptions), causing noticeable freezes
when navigating to Feed during startup.
Root causes and fixes:
- getRSSItems matched items on the full XML (16ms/feed) AND fetchEpisodes
ran a separate getRSSChannel regex (20ms/feed) — a redundant 5MB scan.
Eliminated getRSSChannel; parseChannelCoverUrl now works on the full XML
directly (itunes:image appears before items, so the first match is the
channel cover).
- parseEpisodesIncremental ran getRSSItems (full-XML regex) + the first
25-item parse chunk before yielding. Added yieldToUI() after getRSSItems
so the renderer paints before parsing begins.
- Reduced PARSE_CHUNK_SIZE from 25 to 5 so each sync block between yields
is at most 5 × parseRSSItem (~5ms), not 25 × (~25ms).
- Added yieldToUI() before sortEpisodesReverseChronological in
fetchEpisodes and loadMoreEpisodesForFeed so the sort doesn't pile on
the last parse chunk.
- Added yieldToUI() after response.text() in fetchEpisodes so the renderer
gets a turn before any sync regex work begins.
Measured with 10 feeds × 500 episodes × 10KB descriptions (worst case):
max event-loop block 195ms → 53ms, total blocking 593ms → 292ms.
MouseEvent coordinates are terminal-absolute, so the bar's seek handler
must subtract its own absolute left edge (renderable ref) instead of
treating the mouse x as bar-local. Clicking was off by the width of the
parent/Up pane (~20%) plus chrome. Also drop the empty played-text node
at position 0, which rendered a phantom space column and shifted the
drawn bar one char when playback started.
- ProgressBar: full-width played/remaining bar in the player pane, click-to-seek;
waveform no longer handles seeking or the played/future color split (pure visual)
- bars: 2 terminal rows per bar (16 levels) via barChars, partial block in the
top row so the column renders continuously
- fix bars maxing at audio start: disable cava autosens (silence gain-ramp),
pre-warm the malloc'd FFT window with zeros, skip partial FFT windows
- createBarScaler peak follower + power curve replaces cava autosens for
level-to-height mapping (src/utils/bar-mapping.ts, unit-tested)
