init

server/internal/room/service.go

@@ -0,0 +1,139 @@
+package room
+
+import (
+	"context"
+	"crypto/rand"
+	"errors"
+	"math/big"
+	"strings"
+	"time"
+)
+
+const alphabet = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789"
+
+type Store interface {
+	CreateRoom(ctx context.Context, r Room) error
+	GetRoom(ctx context.Context, code string) (Room, error)
+	SaveRoom(ctx context.Context, r Room) error
+}
+
+type Service struct {
+	store              Store
+	codeLength         int
+	emptyTTL           time.Duration
+	ownerReconnectHold time.Duration
+}
+
+func NewService(st Store, codeLength int, emptyTTL, ownerReconnectHold time.Duration) *Service {
+	return &Service{
+		store:              st,
+		codeLength:         codeLength,
+		emptyTTL:           emptyTTL,
+		ownerReconnectHold: ownerReconnectHold,
+	}
+}
+
+func (s *Service) Create(ctx context.Context) (Room, error) {
+	for i := 0; i < 10; i++ {
+		code, err := randomCode(s.codeLength)
+		if err != nil {
+			return Room{}, err
+		}
+		r := New(code, s.emptyTTL)
+		if err := s.store.CreateRoom(ctx, r); err == nil {
+			return r, nil
+		}
+	}
+	return Room{}, errors.New("failed to allocate room code")
+}
+
+func (s *Service) Join(ctx context.Context, code, deviceID string, onlineCount int) (Room, bool, error) {
+	code = strings.ToUpper(strings.TrimSpace(code))
+	if code == "" || deviceID == "" {
+		return Room{}, false, errors.New("room code and device id are required")
+	}
+
+	r, err := s.store.GetRoom(ctx, code)
+	if err != nil {
+		return Room{}, false, err
+	}
+	now := NowMS()
+	if r.OwnerDeviceID == "" {
+		r.OwnerDeviceID = deviceID
+	}
+	if r.OwnerDeviceID == deviceID {
+		r.OwnerLastSeenAt = now
+	}
+	r.OnlineCount = onlineCount
+	if err := s.store.SaveRoom(ctx, r); err != nil {
+		return Room{}, false, err
+	}
+	return r, r.OwnerDeviceID == deviceID, nil
+}
+
+func (s *Service) Get(ctx context.Context, code string) (Room, error) {
+	return s.store.GetRoom(ctx, strings.ToUpper(strings.TrimSpace(code)))
+}
+
+func (s *Service) SetOnlineCount(ctx context.Context, code string, count int) error {
+	r, err := s.Get(ctx, code)
+	if err != nil {
+		return err
+	}
+	r.OnlineCount = count
+	return s.store.SaveRoom(ctx, r)
+}
+
+func (s *Service) SetSource(ctx context.Context, code, deviceID string, src Source) (Room, error) {
+	r, err := s.Get(ctx, code)
+	if err != nil {
+		return Room{}, err
+	}
+	if r.OwnerDeviceID != deviceID {
+		return Room{}, errors.New("only room owner can configure source")
+	}
+	if src.Mode == "" {
+		src.Mode = SourceModeDirect
+	}
+	if src.Mode != SourceModeDirect && src.Mode != SourceModeProxy {
+		return Room{}, errors.New("source mode must be direct or proxy")
+	}
+	if strings.TrimSpace(src.URL) == "" {
+		return Room{}, errors.New("source url is required")
+	}
+	if src.Mode == SourceModeProxy {
+		src.ProxyPath = "/api/rooms/" + r.Code + "/stream"
+	}
+	r.Source = &src
+	r.Playback = Playback{State: PlaybackIdle, ServerUpdatedAt: NowMS()}
+	if err := s.store.SaveRoom(ctx, r); err != nil {
+		return Room{}, err
+	}
+	return r, nil
+}
+
+func (s *Service) UpdatePlayback(ctx context.Context, code string, p Playback) (Room, error) {
+	r, err := s.Get(ctx, code)
+	if err != nil {
+		return Room{}, err
+	}
+	p.ServerUpdatedAt = NowMS()
+	r.Playback = p
+	if err := s.store.SaveRoom(ctx, r); err != nil {
+		return Room{}, err
+	}
+	return r, nil
+}
+
+func randomCode(n int) (string, error) {
+	var b strings.Builder
+	b.Grow(n)
+	for i := 0; i < n; i++ {
+		x, err := rand.Int(rand.Reader, big.NewInt(int64(len(alphabet))))
+		if err != nil {
+			return "", err
+		}
+		b.WriteByte(alphabet[x.Int64()])
+	}
+	return b.String(), nil
+}