navidrome/core/artwork/artwork.go

package artwork

import (
	"context"
	"errors"
	_ "image/gif"
	"io"
	"time"

	"github.com/navidrome/navidrome/core/ffmpeg"
	"github.com/navidrome/navidrome/log"
	"github.com/navidrome/navidrome/model"
	"github.com/navidrome/navidrome/utils/cache"
	_ "golang.org/x/image/webp"
)

type Artwork interface {
	Get(ctx context.Context, id string, size int) (io.ReadCloser, time.Time, error)
}

func NewArtwork(ds model.DataStore, cache cache.FileCache, ffmpeg ffmpeg.FFmpeg) Artwork {
	return &artwork{ds: ds, cache: cache, ffmpeg: ffmpeg}
}

type artwork struct {
	ds     model.DataStore
	cache  cache.FileCache
	ffmpeg ffmpeg.FFmpeg
}

type artworkReader interface {
	cache.Item
	LastUpdated() time.Time
	Reader(ctx context.Context) (io.ReadCloser, string, error)
}

func (a *artwork) Get(ctx context.Context, id string, size int) (reader io.ReadCloser, lastUpdate time.Time, err error) {
	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
	defer cancel()

	var artID model.ArtworkID
	if id != "" {
		artID, err = model.ParseArtworkID(id)
		if err != nil {
			return nil, time.Time{}, errors.New("invalid ID")
		}
	}

	artReader, err := a.getArtworkReader(ctx, artID, size)
	if err != nil {
		return nil, time.Time{}, err
	}

	r, err := a.cache.Get(ctx, artReader)
	if err != nil && !errors.Is(err, context.Canceled) {
		log.Error(ctx, "Error accessing image cache", "id", id, "size", size, err)
	}
	return r, artReader.LastUpdated(), err
}

func (a *artwork) getArtworkReader(ctx context.Context, artID model.ArtworkID, size int) (artworkReader, error) {
	var artReader artworkReader
	var err error
	if size > 0 {
		artReader, err = resizedFromOriginal(ctx, a, artID, size)
	} else {
		switch artID.Kind {
		case model.KindAlbumArtwork:
			artReader, err = newAlbumArtworkReader(ctx, a, artID)
		case model.KindMediaFileArtwork:
			artReader, err = newMediafileArtworkReader(ctx, a, artID)
		default:
			artReader, err = newPlaceholderReader(ctx, artID)
		}
	}
	return artReader, err
}