🎉 live server seems to be working now

internal/live/roster.go

@@ -0,0 +1,58 @@
+package live
+
+import (
+	"sort"
+	"sync"
+	"time"
+)
+
+// RosterEntry is one observed Sendspin client. Populated from
+// client/hello messages — independent of whether the connection was
+// then accepted or rejected. This is what gives the UI the ability to
+// show the *actual* `client_id` of every speaker on the network, even
+// when ClientFilter rejected its current attempt.
+type RosterEntry struct {
+	ClientID string    `json:"client_id"`
+	Name     string    `json:"name"`
+	LastSeen time.Time `json:"last_seen"`
+}
+
+// Roster caches every (client_id, name) pair the sendspin server has
+// observed via client/hello. Records are kept indefinitely — speakers
+// usually keep the same client_id across reboots, so a stale entry
+// remains useful when the user is configuring presets offline.
+type Roster struct {
+	mu      sync.RWMutex
+	entries map[string]RosterEntry
+}
+
+func NewRoster() *Roster {
+	return &Roster{entries: make(map[string]RosterEntry)}
+}
+
+// Record is intended to be plugged into ServerConfig.OnClientHello.
+// Updates the entry's LastSeen on every call so the UI can show
+// "active now" vs. "last seen 5 minutes ago".
+func (r *Roster) Record(clientID, name string) {
+	if clientID == "" {
+		return
+	}
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.entries[clientID] = RosterEntry{
+		ClientID: clientID,
+		Name:     name,
+		LastSeen: time.Now(),
+	}
+}
+
+func (r *Roster) List() []RosterEntry {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	out := make([]RosterEntry, 0, len(r.entries))
+	for _, e := range r.entries {
+		out = append(out, e)
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].ClientID < out[j].ClientID })
+	return out
+}