Move artwork handling to its own package

core/artwork/sources.go

@@ -0,0 +1,113 @@
+package artwork
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"strings"
+
+	"github.com/dhowden/tag"
+	"github.com/navidrome/navidrome/consts"
+	"github.com/navidrome/navidrome/core/ffmpeg"
+	"github.com/navidrome/navidrome/log"
+	"github.com/navidrome/navidrome/model"
+	"github.com/navidrome/navidrome/resources"
+)
+
+type sourceFunc func() (io.ReadCloser, string, error)
+
+func (f sourceFunc) String() string {
+	name := runtime.FuncForPC(reflect.ValueOf(f).Pointer()).Name()
+	name = strings.TrimPrefix(name, "github.com/navidrome/navidrome/core.")
+	name = strings.TrimPrefix(name, "(*artwork).")
+	name = strings.TrimSuffix(name, ".func1")
+	return name
+}
+
+func (a *artwork) fromAlbum(ctx context.Context, id model.ArtworkID) sourceFunc {
+	return func() (io.ReadCloser, string, error) {
+		r, path, err := a.get(ctx, id, 0)
+		if err != nil {
+			return nil, "", err
+		}
+		return r, path, nil
+	}
+}
+
+func fromExternalFile(ctx context.Context, files string, pattern string) sourceFunc {
+	return func() (io.ReadCloser, string, error) {
+		for _, file := range filepath.SplitList(files) {
+			_, name := filepath.Split(file)
+			match, err := filepath.Match(pattern, strings.ToLower(name))
+			if err != nil {
+				log.Warn(ctx, "Error matching cover art file to pattern", "pattern", pattern, "file", file)
+				continue
+			}
+			if !match {
+				continue
+			}
+			f, err := os.Open(file)
+			if err != nil {
+				log.Warn(ctx, "Could not open cover art file", "file", file, err)
+				continue
+			}
+			return f, file, err
+		}
+		return nil, "", fmt.Errorf("pattern '%s' not matched by files %v", pattern, files)
+	}
+}
+
+func fromTag(path string) sourceFunc {
+	return func() (io.ReadCloser, string, error) {
+		if path == "" {
+			return nil, "", nil
+		}
+		f, err := os.Open(path)
+		if err != nil {
+			return nil, "", err
+		}
+		defer f.Close()
+
+		m, err := tag.ReadFrom(f)
+		if err != nil {
+			return nil, "", err
+		}
+
+		picture := m.Picture()
+		if picture == nil {
+			return nil, "", fmt.Errorf("no embedded image found in %s", path)
+		}
+		return io.NopCloser(bytes.NewReader(picture.Data)), path, nil
+	}
+}
+
+func fromFFmpegTag(ctx context.Context, ffmpeg ffmpeg.FFmpeg, path string) sourceFunc {
+	return func() (io.ReadCloser, string, error) {
+		if path == "" {
+			return nil, "", nil
+		}
+		r, err := ffmpeg.ExtractImage(ctx, path)
+		if err != nil {
+			return nil, "", err
+		}
+		defer r.Close()
+		buf := new(bytes.Buffer)
+		_, err = io.Copy(buf, r)
+		if err != nil {
+			return nil, "", err
+		}
+		return io.NopCloser(buf), path, nil
+	}
+}
+
+func fromPlaceholder() sourceFunc {
+	return func() (io.ReadCloser, string, error) {
+		r, _ := resources.FS().Open(consts.PlaceholderAlbumArt)
+		return r, consts.PlaceholderAlbumArt, nil
+	}
+}