ok trnscode swp

internal/api/api.go

@@ -1,8 +1,11 @@
 package api
 
 import (
+	"bytes"
 	"encoding/json"
+	"fmt"
 	"net/http"
+	"os/exec"
 	"strconv"
 	"strings"
 
@@ -27,6 +30,7 @@ func NewRouter(lib *library.Library) http.Handler {
 	r.Get("/api/search", searchHandler(lib))
 	r.Get("/api/rescan", rescanHandler(lib))
 	r.Get("/api/stream/{id}", streamHandler(lib))
+	r.Get("/api/subtitles/{id}/{index}", subtitleHandler(lib))
 
 	return r
 }
@@ -101,12 +105,15 @@ func detailHandler(lib *library.Library) http.HandlerFunc {
 		probeResult, err := probe.Run(fullPath)
 		if err != nil {
 			writeJSON(w, http.StatusOK, map[string]any{
-				"item":       item,
-				"probe":      nil,
+				"item":        item,
+				"probe":       nil,
 				"probe_error": err.Error(),
 			})
 			return
 		}
+		for i := range probeResult.Subtitles {
+			probeResult.Subtitles[i].URL = fmt.Sprintf("/api/subtitles/%s/%d", id, probeResult.Subtitles[i].Index)
+		}
 
 		writeJSON(w, http.StatusOK, map[string]any{
 			"item":  item,
@@ -142,6 +149,75 @@ func streamHandler(lib *library.Library) http.HandlerFunc {
 	}
 }
 
+func subtitleHandler(lib *library.Library) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id := chi.URLParam(r, "id")
+		index, err := strconv.Atoi(chi.URLParam(r, "index"))
+		if err != nil || index < 0 {
+			http.Error(w, "invalid subtitle index", http.StatusBadRequest)
+			return
+		}
+
+		_, fullPath, ok := lib.Get(id)
+		if !ok {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+
+		metadata, err := probe.Run(fullPath)
+		if err != nil {
+			http.Error(w, "unable to inspect media", http.StatusInternalServerError)
+			return
+		}
+
+		var subtitle *probe.SubTrack
+		for i := range metadata.Subtitles {
+			if metadata.Subtitles[i].Index == index {
+				subtitle = &metadata.Subtitles[i]
+				break
+			}
+		}
+		if subtitle == nil {
+			http.Error(w, "subtitle track not found", http.StatusNotFound)
+			return
+		}
+
+		if !isTextSubtitleCodec(subtitle.Codec) {
+			http.Error(w, fmt.Sprintf("subtitle codec %q requires OCR or burn-in", subtitle.Codec), http.StatusUnsupportedMediaType)
+			return
+		}
+
+		cmd := exec.CommandContext(r.Context(), "ffmpeg",
+			"-v", "error",
+			"-i", fullPath,
+			"-map", fmt.Sprintf("0:%d", index),
+			"-c:s", "webvtt",
+			"-f", "webvtt",
+			"pipe:1",
+		)
+		var stdout, stderr bytes.Buffer
+		cmd.Stdout = &stdout
+		cmd.Stderr = &stderr
+		if err := cmd.Run(); err != nil {
+			http.Error(w, fmt.Sprintf("subtitle conversion failed: %s", strings.TrimSpace(stderr.String())), http.StatusInternalServerError)
+			return
+		}
+
+		w.Header().Set("Content-Type", "text/vtt; charset=utf-8")
+		w.Header().Set("Cache-Control", "public, max-age=86400")
+		_, _ = w.Write(stdout.Bytes())
+	}
+}
+
+func isTextSubtitleCodec(codec string) bool {
+	switch strings.ToLower(codec) {
+	case "ass", "ssa", "subrip", "srt", "text", "webvtt", "mov_text":
+		return true
+	default:
+		return false
+	}
+}
+
 func rescanHandler(lib *library.Library) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		go lib.Scan()