add local MXL video adapter

internal/adapter/mxl/video.go

@@ -0,0 +1,91 @@
+package mxladapter
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"mxl-player/internal/playback"
+	"mxl-player/internal/source"
+)
+
+const DefaultVideoReadTimeout = 200 * time.Millisecond
+
+type VideoFactory struct {
+	ReadTimeout time.Duration
+}
+
+type videoReader struct {
+	source  *source.Source
+	timeout time.Duration
+}
+
+var _ playback.VideoReaderFactory = VideoFactory{}
+var _ playback.VideoReader = (*videoReader)(nil)
+
+func (f VideoFactory) OpenVideo(
+	ctx context.Context,
+	config playback.FeedConfig,
+) (playback.VideoReader, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	if err := config.Validate(); err != nil {
+		return nil, &source.SourceError{
+			Op:   "validate video feed",
+			Kind: source.ErrorKindInvalidConfig,
+			Err:  err,
+		}
+	}
+	if !config.IsConfigured() {
+		return nil, &source.SourceError{
+			Op:   "validate video feed",
+			Kind: source.ErrorKindInvalidConfig,
+			Err:  errors.New("video feed is not configured"),
+		}
+	}
+
+	src, err := source.Open(config.Domain, config.UUID)
+	if err != nil {
+		return nil, fmt.Errorf("open local MXL video: %w", err)
+	}
+
+	if err := ctx.Err(); err != nil {
+		_ = src.Close()
+		return nil, err
+	}
+
+	timeout := f.ReadTimeout
+	if timeout <= 0 {
+		timeout = DefaultVideoReadTimeout
+	}
+
+	return &videoReader{
+		source:  src,
+		timeout: timeout,
+	}, nil
+}
+
+func (r *videoReader) ReadVideo(
+	ctx context.Context,
+) (playback.VideoFrame, error) {
+	frame, err := r.source.NextCtx(ctx, r.timeout)
+	if err != nil {
+		return playback.VideoFrame{}, err
+	}
+
+	return playback.VideoFrame{
+		Index:   frame.Index,
+		Width:   frame.Width,
+		Height:  frame.Height,
+		Stride:  frame.Stride,
+		Size:    frame.Size,
+		Invalid: frame.Invalid,
+		Payload: frame.Payload,
+	}, nil
+}
+
+func (r *videoReader) Close() error {
+	return r.source.Close()
+}