feat(notify): make the queue and history caps settable

A lowered cap applies at the next add rather than at once, so reloading
the config never drops a notification the user has not seen.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

2 files changed, 40 insertions, 8 deletions

diff --git a/internal/notify/store.go b/internal/notify/store.go
index 7a1a745..3648983 100644
--- a/internal/notify/store.go
+++ b/internal/notify/store.go
@@ -36,11 +36,6 @@ type live struct {
 	Closed bool
 }
 
-const (
-	liveCap    = 20
-	historyCap = 20
-)
-
 // Store holds the live queue and the history ring. Time, signals and file
 // writes are injected, so the whole thing is tested without a bus or a clock.
 type Store struct {
@@ -49,6 +44,8 @@ type Store struct {
 	order       []uint32
 	entries     map[uint32]*live
 	history     []*live
+	liveCap     int
+	historyCap  int
 	emit        func(id, reason uint32)
 	publish     func(live, history []Popup)
 	removeImage func(string)
@@ -58,6 +55,8 @@ func NewStore(emit func(id, reason uint32), publish func(live, history []Popup),
 	return &Store{
 		nextID:      1,
 		entries:     map[uint32]*live{},
+		liveCap:     DefaultConfig().LiveCap,
+		historyCap:  DefaultConfig().HistoryCap,
 		emit:        emit,
 		publish:     publish,
 		removeImage: removeImage,
@@ -168,6 +167,16 @@ func (s *Store) ClearHistory() {
 	s.publishLocked()
 }
 
+// SetCaps changes the queue and history bounds. Nothing is trimmed here: a
+// reload must not silently drop live notifications, so a lowered cap applies
+// at the next add.
+func (s *Store) SetCaps(live, history int) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.liveCap = live
+	s.historyCap = history
+}
+
 // Actionable reports whether a client is still listening on the id.
 func (s *Store) Actionable(id uint32) bool {
 	s.mu.Lock()
@@ -223,13 +232,13 @@ func (s *Store) fileLocked(n *live, reason uint32) {
 		s.emit(n.ID, reason)
 	}
 	s.history = append([]*live{n}, s.history...)
-	if len(s.history) > historyCap {
-		s.history = s.history[:historyCap]
+	if len(s.history) > s.historyCap {
+		s.history = s.history[:s.historyCap]
 	}
 }
 
 func (s *Store) evictLocked() {
-	for len(s.order) > liveCap {
+	for len(s.order) > s.liveCap {
 		id := s.order[len(s.order)-1]
 		n := s.entries[id]
 		s.removeLocked(id)
diff --git a/internal/notify/store_test.go b/internal/notify/store_test.go
index 13f78dc..cc351be 100644
--- a/internal/notify/store_test.go
+++ b/internal/notify/store_test.go
@@ -164,3 +164,26 @@ func TestStoreRemovesImageOnReplace(t *testing.T) {
 		t.Fatalf("replace removed %v", removed)
 	}
 }
+
+func TestSetCapsAppliesAtNextAdd(t *testing.T) {
+	s, _ := newTestStore()
+	for i := 0; i < 5; i++ {
+		id, _ := s.Add(popup("a"), "", 0)
+		s.Dismiss(id, 2)
+	}
+	for i := 0; i < 4; i++ {
+		s.Add(popup("a"), "", 0)
+	}
+	s.SetCaps(2, 3)
+	// Lowering a cap drops nothing by itself.
+	if got := len(s.historySnapshot()); got != 5 {
+		t.Fatalf("history after SetCaps = %d, want 5", got)
+	}
+	s.Add(popup("a"), "", 0)
+	if got := len(s.order); got != 2 {
+		t.Errorf("live = %d, want 2", got)
+	}
+	if got := len(s.historySnapshot()); got != 3 {
+		t.Errorf("history = %d, want 3", got)
+	}
+}