Covers: initial state, TOGGLE, FORCE_MUTE (incl. override-while-off),
AUTO_MUTE, AUTO_UNMUTE, RESTORE_MUTED, RESTORE_UNMUTED, ROLE_PROMOTED,
ctx.source pinning per event, observer notification on every transition,
mod-mute idempotency, and the documented invariant that the FSM itself
does NOT enforce "mod-mute is sticky" — policy lives at the call site.
102/0 passing.
`muted` was a bare global mutated from 8+ sites (btn-mute click, peer-force-muted,
role promote/demote, self-listener enable/disable, leave handler, sessionStorage
restore). Each call site also had to remember to call applyMuteState() and
sendMicState(). Drift was inevitable — a recent regression where self-listener
toggle muted the wrong direction came straight from this implicit-state pile.
New shape:
- muteSpec: states { on, off }, events { TOGGLE, FORCE_MUTE, AUTO_MUTE,
AUTO_UNMUTE, RESTORE_MUTED, RESTORE_UNMUTED, ROLE_PROMOTED }, ctx.source
tracks who muted us ('self', 'mod', 'self-listener').
- `muted` is now a getter over roomMachines.mute.state — single source of truth.
- One observer drives applyMuteState + sendMicState + sessionStorage persistence
+ log line on every transition.
- Imperative call sites only dispatch events; they no longer touch side effects.
Tests: test/zebra-fsm.test.js harness updated to extract muteSpec (same brace-
matched-regex pattern as selfListenerSpec). 88/0 passing. MuteFSM-specific
transition tests are next.
Pattern is now load-bearing — call/publish/subscribe/remote-tile/self-listener/
mute all live as FSMs with the same shape.
Fox 2026-06-04 directive: "all systems need state machines." Self-
listener is already an FSM (commit f4dbc5c). Next system: the
top-line connection chrome (entry-row visibility, sec-room reveal,
dot color, leave/mute button visibility, status text, btn-enter
disabled). Previously these were scattered classList + setStatus
writes across welcome, peer-booted (self), btn-leave click, and
handleBlocked — easy to drift, every UI bug fox flagged ("dot still
green after kick", "entry row should be hidden when joined", "leave
button gone after kick") was a different leaf of this implicit
state model.
Wire applyCallStateUI(state, prev, ctx) as a roomMachines.call
observer. Single function, six branches (idle/connecting/joined/
reconnecting/leaving/booted), drives every relevant DOM toggle.
callSpec gains a `bootedAction` context field — 'kick' | 'ban' |
'blocked' | null — set by BOOTED's action so the UI observer can
render the right status ('kicked from this space' vs 'banned from
this space' vs 'blocked from this space') AND decide whether to
re-enable btn-enter (kick: yes, can re-enter; ban/blocked: no).
Call sites updated:
- handleBlocked: now passes { action: 'blocked' } in BOOTED payload
- case 'peer-booted' (self): now passes { action: m.action } so
kick vs ban propagates to the FSM
- btn-leave click: imperative chrome removed (was a 9-line
classList chain), replaced by send('LEAVE') + send('DONE') —
the observer handles the rest
- joinSpace: removed imperative btn-enter.disabled / setStatus
- case 'welcome': removed imperative dot/buttons/sec-room/row-entry
toggles — observer covers them
Tests added in test/zebra-fsm.test.js (now 88/88):
- BOOTED with action=kick → bootedAction=kick
- BOOTED with action=ban → bootedAction=ban
- BOOTED with action=blocked → bootedAction=blocked
- BOOTED with no action defaults to kick (back-compat)
- BOOTED → ACK → idle clears bootedAction
Future migrations should follow this pattern: add a state field to
the spec, hoist the imperative side effects into a switch in an
observer, leave a comment at the OLD imperative location explaining
the migration so the next reader doesn't reintroduce drift.
Fox 2026-06-04 directive: every system should be a state machine
with unit + integration + functional test coverage. Implicit-state
defects keep biting (kicked-listener-UI-still-green, two-kick race,
cohost-toggle-kills-phone, audio-wedge-no-recovery). Starting the
formalization with the most-broken-today system: self-listener mode.
Spec (selfListenerSpec):
off ──ENABLE / TOGGLE──▶ on
on ──DISABLE / TOGGLE / UNMUTE / DEMOTED / CLEAR──▶ off
Sits next to publishSpec, subscribeSpec, callSpec, remoteTileSpec
in zebra-spaces.html. Composed by wireZebraMachines() into
roomMachines.selfListener.
UNMUTE edge encodes fox's invariant: "unmuting should seamlessly
switch them back to the now of the conversation webrtc mesh" — if
the user clicks unmute while on, they implicitly drop back to off.
Side effects (mic mute, streamMode enrolment, remoteAudio muting)
move out of enableSelfListenerMode/disableSelfListenerMode (deleted)
into runSelfListenerEnable / runSelfListenerDisable, called by an
observer attached to the FSM. Pure spec stays Node-testable; the
runtime drives the actual audio plumbing from observed transitions.
Boolean selfListenerMode flag deleted. window.selfListenerMode is
now a getter against the FSM state — single source of truth, no
drift possible. All callers (toggle-button click, mute-unmute,
peer-joined, role-demote, leave) now dispatch FSM events instead
of calling helpers directly.
Tests in test/self-listener-fsm.test.js:
- starts in off
- TOGGLE / ENABLE / DISABLE transitions
- UNMUTE drops to off (the fox-invariant)
- UNMUTE / CLEAR while off is no-op
- DEMOTED drops to off
- CLEAR drops to off
- unknown event refuses
- observer fires on real transitions with prev/state
- runtime observer skips prev===state edges
Existing test/zebra-fsm.test.js updated to extract+expose
selfListenerSpec alongside the other specs (the wireZebraMachines
extract is the integration test).
Makefile gets test-self-listener target + slot in test-all.
All test suites green:
- self-listener: 12 / 12
- zebra-fsm: 83 / 83
- mod-actions: 6 / 6
- web-protocol: 3348 / 3348
- multi-peer-mesh: 8 / 8
- video-track-removal: 18 / 18
Step five — composition layer. wireZebraMachines() returns a coherent
room:
- one CallFSM
- one SubscribeFSM
- three PublishFSMs (mic / screen / camera)
- lazy Map of RemoteTileFSMs created on first tileFor(kind, pubHex)
- tileLeft(pubHex) fans LEFT to every tile keyed by that publisher
Observers wire transitions between machines but the orchestrator
itself stays pure — no WebRTC, no DOM, no fetch. The page's runtime
layers its OWN observers on top to drive real side effects, and the
test extracts the orchestrator directly.
Cascades modelled:
- CallFSM joined (from anything except reconnecting) ── starts the sub
- CallFSM reconnecting → joined does NOT re-START (sub stayed alive)
- CallFSM leaving / booted ── stops sub AND every live publish
- RemoteTileFSMs lazy: tileFor returns the same instance per key
- tileLeft sends LEFT to every kind for that pubHex
+ 11 integration tests + 1 full end-to-end scenario walking through
host publishes mic+screen / listener joins late / listener sees the
screen / host unshares / mute+prune cycle removes the tile / listener
leaves and sub stops.
Total: 83 tests passing. The pure-FSM layer + orchestrator are now
ready to be wired into the imperative call sites in the live runtime.
That's the next step — gradually replace the firefighting code paths
(sfuPublishCamera, sfuSubscribe, role transitions) by feeding events
into these machines from the existing handlers, then observing
state changes to invoke the side effects. Tests catch regressions
on the pure layer while the QA loop catches what touches the wire.
Fourth state machine. Orchestrates the per-leg FSMs:
idle ──ENTER──▶ connecting ──WELCOME──▶ joined ──LEAVE──▶ leaving ──DONE──▶ idle
▲ │ FAILED │ ▲
│ ▼ │ WS_DROPPED │
│ idle ▼ │
│ reconnecting ──WELCOME──▶ joined │
│ │ LEAVE / FAILED │
│ ▼ │
│ leaving ────────────────────────────── ┘
│ ▲
│ │ ACK
└─────────────────────────────────── booted ◀── BOOTED ── (any live state)
Role lives in ctx (host / cohost / speaker / listener). ROLE_CHANGE
re-enters joined so observers fire on every promotion / demotion —
that's how the runtime decides whether to start mic+publish or stop
them, without needing a state per role permutation.
reconnecting handles signal-WS drops without tearing down the
SubscribeFSM or PublishFSMs (WebRTC PCs are independent of the WS).
booted is the explicit terminal for being kicked + ACK returns to
idle so the entry screen comes back.
+ 19 unit tests. test-fsm now 72 passed.
Next step: the integration layer — observers on each FSM that drive
the actual side effects, plus integration tests that compose multiple
FSMs (a CallFSM with SubscribeFSM + RemoteTileFSMs) to assert the
multi-machine interactions match what the live code does.
Third state machine. One instance per incoming screen/camera track,
keyed by kind+pubHex. Codifies the lifecycle:
inactive ──TRACK_ARRIVED──▶ receiving ──MUTED──▶ muted
▲ │
│ UNMUTED │ PRUNE / ENDED
└────────────────────┤
▼
removed
{receiving, muted} + ENDED → removed
* + LEFT → removed
MUTED is a debounce gate, not a deletion: UNMUTED within the runtime's
~1.5s window cancels the prune and stays receiving (transient network
blip). PRUNE fires from the runtime's setTimeout if still muted.
ENDED skips the debounce. LEFT (peer-left) wipes the tile from any
live state. TRACK_ARRIVED in receiving/muted swaps to the new stream
(publisher re-shared before our prune fired).
Removed is terminal — a re-share spins up a fresh FSM. entry into
removed nulls ctx.stream so the runtime can drop refs.
+ 15 unit tests covering happy path, debounce semantics, ENDED
short-circuit, LEFT from every state, re-share refresh, removed
terminality. test-fsm now reports 53 passed.
Second state machine. Models the SFU subscribe leg explicitly:
off ──START──▶ connecting ──CONNECTED──▶ subscribed
│ FAILED │ RENEG
▼ ▼
off renegotiating
│ RENEG_DONE / RENEG_FAILED
▼
subscribed
│ LOST
▼
reconnecting ──CONNECTED──▶ subscribed
│ STOP │ FAILED
▼ ▼
stopping off
│ DONE
▼
off
Renegotiation is its own state so concurrent SSE offers can't race
setRemoteDescription (the bug ae9721e patched imperatively with a
promise queue). A RENEG event during renegotiating parks the SDP on
ctx.pendingOffers; the runtime will drain that queue from an observer
when RENEG_DONE fires. RENEG_FAILED returns to subscribed without
killing the PC — the negotiation attempt is what failed, the channel
itself is still up.
LOST during renegotiating jumps straight to reconnecting (drops the
in-flight reneg cleanly; when the connection comes back the runtime
will re-deliver any still-relevant SDP via fresh RENEGs).
+ 15 new unit tests covering connect, queue, drops, teardown, illegal
transitions. test-fsm now reports 38 passed.
First step of the state-machine refactor. Same self-contained pattern
as the rest of the page — FSMs live inline in web/zebra-spaces.html so
the page-integrity stamp keeps working, and the tests extract them with
the same regex/brace-match technique web-protocol.test.js already uses
(page = source of truth, tests track the page).
Added:
- createFSM(spec): minimal state machine. spec.states[name] has optional
entry/exit hooks and an .on table mapping events → target (string) or
{ target, action }. Observers fire after each transition with
{ state, prev, ev, ctx }. No async in transitions; effects belong in
observers (which can call send() to advance the machine).
- publishSpec: pure transition table for the publish flow.
off ──START──▶ acquiring ──ACQUIRED──▶ negotiating ──NEGOTIATED──▶ live
│ FAILED │ FAILED │ STOP/LOST
▼ ▼ ▼
off stopping ◀──── stopping ──┘
│ DONE
▼
off
One instance per kind (mic / screen / camera). FAILED in negotiating
goes to stopping (not off) so any acquired stream/pc gets torn down.
- test/zebra-fsm.test.js: 23 unit tests covering framework semantics +
publishSpec happy path + error/cancel paths + illegal-transition
no-ops. Function-constructor scope handles const-leak; bare eval()
doesn't expose const declarations to the harness.
- Makefile: test-fsm target + included in test-all.
Next: SubscribeFSM, CallFSM, RemoteTileFSM. Then wire each into the
imperative call sites progressively, replacing the firefighting code.
