refactor media service helpers

internal/service/media_cache.go

@@ -0,0 +1,49 @@
+package service
+
+import (
+	"context"
+	"crypto/sha1"
+	"encoding/hex"
+	"fmt"
+	"sort"
+	"strings"
+
+	"github.com/ShukeBta/MediaStationGo/internal/model"
+	"github.com/ShukeBta/MediaStationGo/internal/repository"
+)
+
+type mediaListCacheValue struct {
+	Items []model.Media `json:"items"`
+	Total int64         `json:"total"`
+}
+
+func (s *MediaService) mediaListCacheKey(libraryID string, libraryIDs []string, page, pageSize int, filter repository.MediaQueryFilter) string {
+	allowed := append([]string(nil), filter.AllowedLibraryIDs...)
+	hidden := append([]string(nil), filter.HiddenLibraryIDs...)
+	libs := append([]string(nil), libraryIDs...)
+	sort.Strings(allowed)
+	sort.Strings(hidden)
+	sort.Strings(libs)
+	sum := sha1.Sum([]byte(strings.Join([]string{
+		libraryID,
+		strings.Join(libs, ","),
+		fmt.Sprintf("%d:%d:%t", page, pageSize, filter.IncludeNSFW),
+		strings.Join(allowed, ","),
+		strings.Join(hidden, ","),
+	}, "|")))
+	return "media:list:" + hex.EncodeToString(sum[:])
+}
+
+func (s *MediaService) mediaCacheTTLSeconds() int {
+	if s == nil || s.cfg == nil || s.cfg.Cache.MediaTTLSeconds < 1 {
+		return 15
+	}
+	return s.cfg.Cache.MediaTTLSeconds
+}
+
+func (s *MediaService) invalidateMediaCache(ctx context.Context) {
+	if s != nil && s.cache != nil {
+		s.cache.DeletePrefix(ctx, "media:")
+		s.cache.DeletePrefix(ctx, "stats:")
+	}
+}