split subtitle service helpers

2026-10-12 00:06:37 +08:00 · 2026-06-27 02:24:52 +08:00
parent 44ebe47f64
commit 0c4d871464
3 changed files with 240 additions and 221 deletions
@@ -0,0 +1,172 @@
+package service
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"path/filepath"
+	"strings"
+
+	"go.uber.org/zap"
+
+	"github.com/ShukeBta/MediaStationGo/internal/model"
+	"github.com/ShukeBta/MediaStationGo/internal/service/cloud"
+)
+
+func discoverCloudSubtitles(ctx context.Context, s *SubtitleService, m model.Media) []SubtitleTrack {
+	if s == nil || s.storage == nil {
+		return []SubtitleTrack{}
+	}
+	typ, mediaRef, ok := cloudSubtitleMediaRef(m)
+	if !ok {
+		return []SubtitleTrack{}
+	}
+	dirRef, mediaName := splitCloudRef(mediaRef)
+	if mediaName == "" {
+		return []SubtitleTrack{}
+	}
+	base := strings.TrimSuffix(mediaName, filepath.Ext(mediaName))
+	entries, err := s.storage.CloudList(ctx, typ, dirRef)
+	if err != nil {
+		if s.log != nil {
+			s.log.Debug("list cloud subtitles failed", zap.String("provider", typ), zap.String("dir", dirRef), zap.Error(err))
+		}
+		return []SubtitleTrack{}
+	}
+	tracks := cloudSubtitleTracks(typ, entries, base, false)
+	for _, entry := range entries {
+		if !entry.IsDir || !isSubtitleDirectory(entry.Name) || strings.TrimSpace(entry.ID) == "" {
+			continue
+		}
+		subEntries, err := s.storage.CloudList(ctx, typ, entry.ID)
+		if err != nil {
+			continue
+		}
+		tracks = append(tracks, cloudSubtitleTracks(typ, subEntries, base, true)...)
+	}
+	return tracks
+}
+
+func cloudSubtitleTracks(typ string, entries []cloud.FileEntry, base string, subdir bool) []SubtitleTrack {
+	tracks := make([]SubtitleTrack, 0)
+	baseLower := strings.ToLower(base)
+	for _, entry := range entries {
+		if entry.IsDir {
+			continue
+		}
+		ext := strings.ToLower(filepath.Ext(entry.Name))
+		codec, ok := extToCodec[ext]
+		if !ok {
+			continue
+		}
+		fullName := strings.TrimSuffix(entry.Name, ext)
+		if !subdir && !strings.HasPrefix(strings.ToLower(fullName), baseLower) {
+			continue
+		}
+		ref := cloudEntryRef(typ, entry.ID, entry.PickCode)
+		if ref == "" {
+			continue
+		}
+		lang := detectLang(fullName, base)
+		tracks = append(tracks, SubtitleTrack{
+			Lang:  lang,
+			Label: lang,
+			Path:  buildCloudSubtitlePath(typ, ref, entry.Name),
+			Codec: codec,
+		})
+	}
+	return tracks
+}
+
+func cloudSubtitleMediaRef(m model.Media) (typ, ref string, ok bool) {
+	if info, parsed := ParseCloudLibraryMount(m.Path); parsed && strings.TrimSpace(info.DisplayDir) != "" {
+		return info.Provider, info.DisplayDir, true
+	}
+	if typ, ref, parsed := parseCloudMediaPlaybackURL(m.STRMURL); parsed {
+		return typ, ref, true
+	}
+	return "", "", false
+}
+
+func splitCloudRef(ref string) (dir, name string) {
+	ref = strings.Trim(strings.ReplaceAll(strings.TrimSpace(ref), "\\", "/"), "/")
+	if ref == "" {
+		return "", ""
+	}
+	idx := strings.LastIndex(ref, "/")
+	if idx < 0 {
+		return "", ref
+	}
+	return ref[:idx], ref[idx+1:]
+}
+
+func isSubtitleDirectory(name string) bool {
+	switch strings.ToLower(strings.TrimSpace(name)) {
+	case "subs", "sub", ".sub", "subtitles", "subtitle":
+		return true
+	default:
+		return false
+	}
+}
+
+func buildCloudSubtitlePath(typ, ref, name string) string {
+	u := url.URL{
+		Scheme: "cloud",
+		Host:   strings.TrimSpace(typ),
+		Path:   "/" + strings.TrimLeft(strings.TrimSpace(ref), "/"),
+	}
+	q := u.Query()
+	q.Set("name", strings.TrimSpace(name))
+	u.RawQuery = q.Encode()
+	return u.String()
+}
+
+func parseCloudSubtitlePath(raw string) (typ, ref, name string, ok bool) {
+	u, err := url.Parse(strings.TrimSpace(raw))
+	if err != nil || strings.ToLower(u.Scheme) != "cloud" || strings.TrimSpace(u.Host) == "" {
+		return "", "", "", false
+	}
+	ref = strings.TrimLeft(u.EscapedPath(), "/")
+	if decoded, err := url.PathUnescape(ref); err == nil {
+		ref = decoded
+	}
+	return strings.TrimSpace(u.Host), strings.TrimSpace(ref), strings.TrimSpace(u.Query().Get("name")), ref != ""
+}
+
+func serveCloudSubtitle(ctx context.Context, s *SubtitleService, m model.Media, typ, ref, name string, w io.Writer) error {
+	if s == nil || s.storage == nil {
+		return errors.New("cloud storage service unavailable")
+	}
+	mediaTyp, _, ok := cloudSubtitleMediaRef(m)
+	if !ok || mediaTyp != typ {
+		return ErrCloudPlaybackUnavailable
+	}
+	allowed := false
+	for _, track := range discoverCloudSubtitles(ctx, s, m) {
+		if track.Path == buildCloudSubtitlePath(typ, ref, name) {
+			allowed = true
+			break
+		}
+	}
+	if !allowed {
+		return fmt.Errorf("path escape")
+	}
+	body, err := s.storage.CloudReadText(ctx, typ, ref, 8<<20)
+	if err != nil {
+		return err
+	}
+	ext := strings.ToLower(filepath.Ext(firstNonEmpty(name, ref)))
+	switch ext {
+	case ".vtt":
+		_, err = io.WriteString(w, body)
+	case ".srt":
+		_, err = io.WriteString(w, srtToVTT(body))
+	case ".ass", ".ssa":
+		_, err = io.WriteString(w, assToVTT(body))
+	default:
+		return errors.New("unsupported subtitle format")
+	}
+	return err
+}