feat: add BotDM re-subscribe upsert with DisableNotification field

docs/superpowers/specs/2026-05-19-botdm-resubscribe-upsert-design.md

@@ -0,0 +1,230 @@
+# BotDM Re-subscribe Upsert + `DisableNotification` Field
+
+**Date:** 2026-05-19
+**Branch:** `claude/fix-room-notification-settings-RqyO1`
+**Scope:** `pkg/model`, `room-worker`
+
+## Problem
+
+A user can mute notifications on a botDM room (the user-facing toggle for that
+field will land in a follow-up PR). When the same user later tries to "open the
+app" again — which on the backend re-issues `chat.user.<account>.request.room.create`
+or `chat.user.<account>.request.room.syncCreateDM` for the bot — the
+subscription document already exists, so the current `BulkCreateSubscriptions`
+swallows the duplicate-key error and returns silently. The pre-existing sub
+keeps its old state, including `DisableNotification = true`, so the user
+remains muted and the re-activation is a no-op.
+
+The desired behaviour is: re-creating a botDM for a user who already has a
+subscription **refreshes the mute/active state** on that subscription —
+`DisableNotification` is cleared, `IsSubscribed` is set to `true`, and
+`JoinedAt` is updated to the new acceptance timestamp. Runtime state
+(`LastSeenAt`, `HasMention`, `ThreadUnread`, `Alert`) is preserved.
+
+`IsSubscribed = true` only appears on the human side of a botDM today
+(`inbox-worker/handler.go:241-246` hard-codes `false` everywhere else), so the
+"re-join" semantics described above are conceptually botDM-only. All other
+membership write paths (channel rooms, regular DMs, add-member) keep their
+current safe insert-only behaviour, which is the right semantics for JetStream
+redelivery idempotency in those flows.
+
+## Scope
+
+In scope:
+
+- Add `DisableNotification bool` to `model.Subscription`.
+- Add a new store method `BulkUpsertSubscriptions` that implements the re-join
+  refresh semantics described above.
+- Wire the two botDM call sites in `room-worker` to use the new method.
+- Re-read canonical subs after the async-path upsert so the
+  `subscription.update` / `MemberAddEvent` fan-out carries persisted state.
+
+Explicitly out of scope (deferred to follow-up PRs):
+
+- A user-facing toggle endpoint to set `DisableNotification`.
+- `notification-worker` filtering: this PR does **not** change
+  `notification-worker`. It will still fan notifications to every sub
+  regardless of `DisableNotification`. End-to-end mute behaviour is wired up
+  separately.
+- Any change to channel-room, regular-DM, or add-member persistence semantics.
+
+## Design
+
+### 1. Model — `pkg/model/subscription.go`
+
+Add a single field next to `Alert`:
+
+```go
+Alert               bool `json:"alert" bson:"alert"`
+DisableNotification bool `json:"disableNotification" bson:"disableNotification"`
+```
+
+No `omitempty`. Matches the convention of `Alert` and `HasMention` and ensures
+the bson document always carries an explicit value. Existing Mongo records
+without the field decode to Go zero value (`false`) — the desired default
+("notifications enabled") — so no migration is required.
+
+Extend the `Subscription` round-trip case in `pkg/model/model_test.go` to set
+`DisableNotification: true` so JSON and BSON marshalling are covered.
+
+### 2. Subscription builder — `room-worker/handler.go`
+
+`newSub` (`handler.go:1040`) constructs every subscription used by every
+membership write path. The zero value of `DisableNotification` already gives
+the desired default (`false`) on fresh inserts, so the `newSub` signature does
+not change. Adding a parameter that is always `false` would be noise.
+
+### 3. Store — `room-worker/store.go` + `room-worker/store_mongo.go`
+
+Add a new interface method alongside `BulkCreateSubscriptions`:
+
+```go
+// BulkUpsertSubscriptions inserts the given subscriptions and, on a
+// (roomId, u.account) collision with an existing document, refreshes the
+// re-activation fields (DisableNotification → false, IsSubscribed,
+// JoinedAt) while preserving the existing document's runtime state
+// (LastSeenAt, HasMention, ThreadUnread, Alert) and identity (_id, u).
+// Intended for botDM re-creation paths only; channel/DM/add-member paths
+// must continue to use BulkCreateSubscriptions for safe redelivery
+// idempotency.
+BulkUpsertSubscriptions(ctx context.Context, subs []*model.Subscription) error
+```
+
+Implementation in `store_mongo.go` uses `BulkWrite` with one
+`UpdateOneModel` per sub:
+
+- **Filter:** `{"roomId": sub.RoomID, "u.account": sub.User.Account}`.
+- **`$set`:** `disableNotification: false`, `isSubscribed: sub.IsSubscribed`,
+  `joinedAt: sub.JoinedAt`. These are the re-activation fields.
+- **`$setOnInsert`:** `_id, u, roomId, siteId, roomType, name, roles,
+  hasMention: false, alert: false`. These are immutable identity fields plus
+  zero-value initialisers for the runtime fields, applied only on first
+  insert.
+- **Upsert:** `true`. Unordered so partial collisions don't halt the batch.
+
+On the update branch, runtime fields (`LastSeenAt`, `HasMention`,
+`ThreadUnread`, `Alert`) are not in `$set`, so Mongo preserves whatever it
+currently holds — an unread mention that arrived between mute and
+re-subscribe is not erased. On the insert branch, `$setOnInsert`
+initialises `hasMention` and `alert` to `false`; `lastSeenAt` and
+`threadUnread` remain unset (their bson tags are `omitempty`).
+
+`mock_store_test.go` is regenerated via `make generate`.
+
+### 4. Wire into botDM paths — `room-worker/handler.go`
+
+Two call sites switch from `BulkCreateSubscriptions` to
+`BulkUpsertSubscriptions`:
+
+1. `processCreateRoom` botDM branch — `handler.go:1163`. The regular-DM
+   branch immediately above (`buildDMSubs` at `handler.go:1161`) stays on
+   `BulkCreateSubscriptions`.
+2. `processSyncCreateDM` botDM branch — `handler.go:1568`. The regular-DM
+   path in the same function stays on `BulkCreateSubscriptions`.
+
+Concretely, both sites become a conditional dispatch:
+
+```go
+if roomType == model.RoomTypeBotDM {
+    err = h.store.BulkUpsertSubscriptions(ctx, subs)
+} else {
+    err = h.store.BulkCreateSubscriptions(ctx, subs)
+}
+```
+
+All other call sites (`processCreateRoomChannel` at `handler.go:1229`,
+add-member flow) are unchanged.
+
+### 5. Re-read after upsert (async path)
+
+The sync path (`processSyncCreateDM`) already re-reads via
+`FindDMSubscription` after the bulk call (`handler.go:1574-1582`) so the
+fan-out carries canonical `_id` and `JoinedAt`. No change there.
+
+The async `processCreateRoom` botDM branch currently hands the in-memory
+`subs` directly to `finishCreateRoom` (`handler.go:1166`). On an upsert that
+hit an existing row, the in-memory `sub.ID` and `sub.JoinedAt` may not match
+the persisted document. Mirror the sync path: after a successful
+`BulkUpsertSubscriptions` in the async botDM branch, call
+`FindDMSubscription` for `(requester.Account, counterpart.Account)` and
+`(counterpart.Account, requester.Account)`, replace the in-memory subs with
+the canonical pair, and pass that into `finishCreateRoom`. This keeps
+`subscription.update` events, `MemberAddEvent`s, and reconcile counts
+operating on persisted state.
+
+## Testing
+
+Per CLAUDE.md, all new code goes through the Red-Green-Refactor TDD cycle.
+
+### Unit tests — `room-worker/handler_test.go`
+
+- `processCreateRoom` botDM happy path: expect `BulkUpsertSubscriptions`
+  (not `BulkCreateSubscriptions`) and the two new `FindDMSubscription`
+  re-reads. Verify the events published downstream carry the re-read sub
+  values (different `_id` than the in-memory pre-upsert sub).
+- `processCreateRoom` regular-DM, `processCreateRoomChannel`, and
+  add-member paths: regression-guard that they still expect
+  `BulkCreateSubscriptions` and **not** `BulkUpsertSubscriptions`.
+- `processSyncCreateDM` botDM happy path: expect
+  `BulkUpsertSubscriptions`. Regular-DM branch still expects
+  `BulkCreateSubscriptions`.
+
+### Integration tests — `room-worker/integration_test.go`
+
+- **Re-join refresh:** Pre-seed a botDM subscription with
+  `DisableNotification = true`, `IsSubscribed = false`, and an old
+  `JoinedAt`. Also set `HasMention = true`, `Alert = true`, and a
+  `LastSeenAt`. Run `processCreateRoom` for the same (roomID, account)
+  pair with a new `acceptedAt`. Assert:
+  - `_id` unchanged from the pre-seeded row.
+  - `DisableNotification == false`, `IsSubscribed == true`,
+    `JoinedAt == new acceptedAt`.
+  - `HasMention == true`, `Alert == true`, `LastSeenAt` unchanged
+    (runtime state preserved).
+- **Fresh insert:** No pre-seeded row. Run `processCreateRoom` botDM.
+  Assert sub is created with `DisableNotification == false`,
+  `IsSubscribed == true` (human side) / `false` (bot side),
+  `HasMention == false`, `Alert == false`.
+- **Regular-DM regression:** Pre-seed a regular-DM sub with
+  `DisableNotification = true`. Run `processCreateRoom` for the same
+  pair (regular DM, not botDM). Assert `DisableNotification` is still
+  `true` — regular-DM path does **not** upsert, so the pre-existing
+  state is preserved (current behaviour, regression guard).
+
+### Model tests
+
+`pkg/model/model_test.go` Subscription round-trip case extended to set
+`DisableNotification = true`, verifying both JSON and BSON tag correctness.
+
+### Coverage
+
+Target ≥90% on the touched files (`room-worker/handler.go`,
+`room-worker/store_mongo.go`) per the project's coverage rules. Cover both
+the upsert-as-insert and upsert-as-update branches, the re-read failure
+path, and the regular-DM no-upsert regression.
+
+## Risks & Open Questions
+
+- **Concurrent mute + re-subscribe race.** If the user mutes
+  (`DisableNotification = true`) at the same instant they re-open the app
+  (triggering this upsert), the upsert can overwrite the just-muted value.
+  Mitigation: the user-facing mute endpoint (out of scope here) lands later
+  and will be the dominant source of mutes; an accidental clear from a
+  racing re-creation is recoverable by re-muting. Calling this out so the
+  follow-up PR's design can address it if needed.
+
+- **`JoinedAt` semantics drift.** Refreshing `JoinedAt` on every botDM
+  re-creation means it is now "last re-join time", not "first join time".
+  No current consumer treats `JoinedAt` as "first join" for botDMs, but
+  worth flagging in case downstream analytics rely on it.
+
+## Out of Scope (Follow-Up PRs)
+
+- User-facing endpoint to toggle `DisableNotification` (probably an HTTP
+  PATCH on the subscription, or a NATS RPC; routed through `room-worker`
+  or `auth-service`).
+- `notification-worker` filter: skip subs where
+  `DisableNotification == true` before fan-out.
+- Frontend mute toggle UI.
+- `docs/client-api.md` update — only required once the client-facing
+  toggle endpoint lands (this PR exposes no new request/response schema).

pkg/model/model_test.go

@@ -455,18 +455,19 @@ func TestSubscriptionJSON(t *testing.T) {
 		hss := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
 		lsa := time.Date(2026, 1, 2, 0, 0, 0, 0, time.UTC)
 		s := model.Subscription{
-			ID:                 "s1",
-			User:               model.SubscriptionUser{ID: "u1", Account: "alice"},
-			RoomID:             "r1",
-			RoomType:           model.RoomTypeChannel,
-			SiteID:             "site-a",
-			Roles:              []model.Role{model.RoleOwner},
-			HistorySharedSince: &hss,
-			JoinedAt:           time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC),
-			LastSeenAt:         &lsa,
-			HasMention:         true,
-			ThreadUnread:       []string{"parent-1", "parent-2"},
-			Alert:              true,
+			ID:                  "s1",
+			User:                model.SubscriptionUser{ID: "u1", Account: "alice"},
+			RoomID:              "r1",
+			RoomType:            model.RoomTypeChannel,
+			SiteID:              "site-a",
+			Roles:               []model.Role{model.RoleOwner},
+			HistorySharedSince:  &hss,
+			JoinedAt:            time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC),
+			LastSeenAt:          &lsa,
+			HasMention:          true,
+			ThreadUnread:        []string{"parent-1", "parent-2"},
+			Alert:               true,
+			DisableNotification: true,
 		}
 		roundTrip(t, &s, &model.Subscription{})
 	})
@@ -518,6 +519,10 @@ func TestSubscriptionJSON_ThreadUnreadOmittedAlertAlwaysPresent(t *testing.T) {
 	assert.True(t, hasAlert, "alert must be present in JSON even when false")
 	assert.Equal(t, false, alertVal)
 
+	disableVal, hasDisable := raw["disableNotification"]
+	assert.True(t, hasDisable, "disableNotification must be present in JSON even when false")
+	assert.Equal(t, false, disableVal)
+
 	var dst model.Subscription
 	require.NoError(t, json.Unmarshal(data, &dst))
 	assert.Nil(t, dst.ThreadUnread, "absent threadUnread must unmarshal to nil")

pkg/model/subscription.go

@@ -25,20 +25,21 @@ type SubscriptionUser struct {
 }
 
 type Subscription struct {
-	ID                 string           `json:"id" bson:"_id"`
-	User               SubscriptionUser `json:"u" bson:"u"`
-	RoomID             string           `json:"roomId" bson:"roomId"`
-	SiteID             string           `json:"siteId" bson:"siteId"`
-	Roles              []Role           `json:"roles" bson:"roles"`
-	Name               string           `json:"name"                    bson:"name"`
-	RoomType           RoomType         `json:"roomType"                bson:"roomType"`
-	IsSubscribed       bool             `json:"isSubscribed,omitempty"  bson:"isSubscribed,omitempty"`
-	HistorySharedSince *time.Time       `json:"historySharedSince,omitempty" bson:"historySharedSince,omitempty"`
-	JoinedAt           time.Time        `json:"joinedAt" bson:"joinedAt"`
-	LastSeenAt         *time.Time       `json:"lastSeenAt,omitempty" bson:"lastSeenAt,omitempty"`
-	HasMention         bool             `json:"hasMention" bson:"hasMention"`
-	ThreadUnread       []string         `json:"threadUnread,omitempty" bson:"threadUnread,omitempty"`
-	Alert              bool             `json:"alert" bson:"alert"`
+	ID                  string           `json:"id" bson:"_id"`
+	User                SubscriptionUser `json:"u" bson:"u"`
+	RoomID              string           `json:"roomId" bson:"roomId"`
+	SiteID              string           `json:"siteId" bson:"siteId"`
+	Roles               []Role           `json:"roles" bson:"roles"`
+	Name                string           `json:"name"                    bson:"name"`
+	RoomType            RoomType         `json:"roomType"                bson:"roomType"`
+	IsSubscribed        bool             `json:"isSubscribed,omitempty"  bson:"isSubscribed,omitempty"`
+	HistorySharedSince  *time.Time       `json:"historySharedSince,omitempty" bson:"historySharedSince,omitempty"`
+	JoinedAt            time.Time        `json:"joinedAt" bson:"joinedAt"`
+	LastSeenAt          *time.Time       `json:"lastSeenAt,omitempty" bson:"lastSeenAt,omitempty"`
+	HasMention          bool             `json:"hasMention" bson:"hasMention"`
+	ThreadUnread        []string         `json:"threadUnread,omitempty" bson:"threadUnread,omitempty"`
+	Alert               bool             `json:"alert" bson:"alert"`
+	DisableNotification bool             `json:"disableNotification" bson:"disableNotification"`
 }
 
 // SubscriptionHRInfo carries the counterpart's HR-directory record on a