Deep-review round 1 on bug/download-mediakind-probe found a real HIGH the prior
review missed:
- resolve_media_facts used a per-field `probe or info` fallback, so a probe that
RAN and deliberately found no video track (cover-art-only audio: attached_pic
skipped; a still image: format-guarded) had its None video overridden by
yt-dlp's stale vcodec. An audio-mode download from a progressive source (info
carries the source's video codec, embed-thumbnail on) was then classified VIDEO
-> a Play button + a broken in-app <video> with no video track. Only the
download path regressed (upload calls probe_media directly).
Fix: gate precedence on whether ffprobe RAN, not per-field. If the probe read
the file, its codec verdict wins outright (a None means 'no such track'); only a
full ffprobe failure falls back to info. Dimensions still gap-fill from info.
Refactored the parsing into _facts_from_probe so resolve_media_facts can see the
raw probe-ran signal; probe_media keeps its 5-tuple (upload + TestProbeClassifier
unchanged).
- tests: the cover-art-audio and still-image resurrection cases, a differing
populated-info precedence case (the prior-flagged gap), and the ffprobe-failed
info fallback — now stubbing run_ffprobe_json so the real parsing + precedence
run together.
Backend gate green (ruff + full pytest).
A downloaded video was silently demoted to a download-only "file" (no
in-app play/edit) whenever yt-dlp's info dict omitted vcodec/acodec — which
it does for Facebook and other sources. Finalize derived media_kind from
those nulls (`derive(None, None)` -> file), so a genuine H.264/AAC MP4
became non-playable in the library.
Fix: probe the finished file on disk (the ground truth) at finalize and
derive from that, falling back to the info dict only for a field the probe
couldn't read. This is the same ffprobe the upload ingest already used, now
extracted to a shared downloads/probe.py so the download worker and the
upload path share one classifier (and can't drift). Also backfills the
stored vcodec/acodec/width/height from the real file.
Tests: TestResolveMediaFacts pins probe-wins-over-info (incl. the Facebook
no-codec case and yt-dlp's literal "none"); upload's probe tests repoint to
the shared module.
peter