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
}