add independent video worker

2026-08-27 10:23:57 +03:00
parent 8cb2d0b88f
commit 862f76c1b8
2 changed files with 503 additions and 0 deletions
@@ -0,0 +1,184 @@
+package playback
+
+import (
+	"context"
+	"errors"
+	"fmt"
+)
+
+var (
+	ErrVideoFactoryRequired      = errors.New("video reader factory is required")
+	ErrVideoSinkRequired         = errors.New("video sink is required")
+	ErrVideoRetryDeciderRequired = errors.New("video decider is required")
+	ErrVideoFeedInactive         = errors.New("video feed is not active")
+)
+
+type VideoWorker struct {
+	factory     VideoReaderFactory
+	sink        VideoSink
+	retry       RetryPolicy
+	shouldRetry retryDecider
+	observer    StatusObserver
+	wait        waitFunc
+}
+
+func NewVideoWorker(
+	factory VideoReaderFactory,
+	sink VideoSink,
+	retry RetryPolicy,
+	shouldRetry func(error) bool,
+	observer StatusObserver,
+) (*VideoWorker, error) {
+	if factory == nil {
+		return nil, ErrVideoFactoryRequired
+	}
+	if sink == nil {
+		return nil, ErrVideoSinkRequired
+	}
+	if shouldRetry == nil {
+		return nil, ErrVideoRetryDeciderRequired
+	}
+	if err := retry.Validate(); err != nil {
+		return nil, fmt.Errorf("validate video retry policy: %w", err)
+	}
+
+	return &VideoWorker{
+		factory:     factory,
+		sink:        sink,
+		retry:       retry,
+		shouldRetry: shouldRetry,
+		observer:    observer,
+		wait:        waitForRetry,
+	}, nil
+}
+
+type stabilityVideoSink struct {
+	sink     VideoSink
+	onStable func()
+	stable   bool
+}
+
+func (s *stabilityVideoSink) ConsumeVideo(
+	ctx context.Context,
+	frame VideoFrame,
+) error {
+	err := s.sink.ConsumeVideo(ctx, frame)
+	if err == nil && !s.stable {
+		s.stable = true
+		if s.onStable != nil {
+			s.onStable()
+		}
+	}
+	return err
+}
+
+func (w *VideoWorker) emit(status Status) {
+	if w.observer != nil {
+		w.observer(status)
+	}
+}
+
+func (w *VideoWorker) Run(
+	ctx context.Context,
+	config FeedConfig,
+) error {
+	if err := config.Validate(); err != nil {
+		return fmt.Errorf("validate video config: %w", err)
+	}
+	if !config.Active {
+		return ErrVideoFeedInactive
+	}
+
+	attemptNumber := 0
+	var latestRetry retryEvent
+
+	attempt := func(ctx context.Context) (bool, error) {
+		attemptNumber++
+
+		state := StateConnecting
+		if attemptNumber > 1 {
+			state = StateReconnecting
+		}
+		w.emit(Status{
+			Unit:    UnitVideo,
+			State:   state,
+			Attempt: attemptNumber,
+		})
+
+		attemptSink := &stabilityVideoSink{
+			sink: w.sink,
+			onStable: func() {
+				w.emit(Status{
+					Unit:    UnitVideo,
+					State:   StatePlaying,
+					Attempt: attemptNumber,
+				})
+			},
+		}
+
+		err := runVideoAttempt(ctx, w.factory, attemptSink, config)
+		return attemptSink.stable, err
+	}
+
+	decide := func(err error) bool {
+		var sinkErr *videoSinkError
+		if errors.As(err, &sinkErr) {
+			return false
+		}
+		return w.shouldRetry(err)
+	}
+
+	observeRetry := func(event retryEvent) {
+		latestRetry = event
+		if !event.WillRetry {
+			return
+		}
+
+		w.emit(Status{
+			Unit:           UnitVideo,
+			State:          StateReconnecting,
+			Attempt:        attemptNumber + 1,
+			FailedAttempts: event.FailedAttempts,
+			RetryIn:        event.RetryIn,
+			Err:            event.Err,
+		})
+	}
+
+	err := runWithRetry(
+		ctx,
+		w.retry,
+		attempt,
+		decide,
+		w.wait,
+		observeRetry,
+	)
+
+	if ctx.Err() != nil {
+		w.emit(Status{
+			Unit:  UnitVideo,
+			State: StateStopping,
+		})
+		w.emit(Status{
+			Unit:  UnitVideo,
+			State: StateIdle,
+		})
+		return ctx.Err()
+	}
+
+	if err != nil {
+		w.emit(Status{
+			Unit:           UnitVideo,
+			State:          StateFailed,
+			Attempt:        attemptNumber,
+			FailedAttempts: latestRetry.FailedAttempts,
+			Err:            err,
+		})
+		return err
+	}
+
+	w.emit(Status{
+		Unit:  UnitVideo,
+		State: StateIdle,
+	})
+	return nil
+}