MeshTerm already stores every channel packet it hears, including those
on channels the device doesn't have. A packet names its channel only by
a one-byte hash, but a public channel's key is derived from its name, so
a candidate name can be tested: derive the key and check the packet's
MAC with it, exactly as the firmware does before decoding. The guide
tries the device's channels, Public, every #name mentioned in a stored
message, and every known region. On one desktop history that names 25
public channels.
A guessed name has to match at least two messages before the guide
shows it. The check compares three bytes, and with thousands of names
against thousands of packets roughly one false match is expected. The
candidates are grouped by their hash byte, so each packet only checks
the ~1/256 that could match; the naive loop took 40 s, this takes 1 s
on 31,000 messages, in a worker thread under a busy card, and the result
is kept for the session while its inputs are unchanged.
"Channel guide…" is the first row of "Add a channel" on the Channels
page, and it stays there when every slot is full. Channels not on the
device come first, and Enter adds one to the next free slot. Channels
the device already has follow with a ✓ the highlight doesn't walk, and a
closing line counts the messages no name matched. Each row shows the
message count, the age of the last message and seven days of activity.
`channels guide` lists the same channels on the command line.
Refs: #25
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Jean-Pierre MartineauandClaude Opus 5.5
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