// backend\main.go

package main

import (
	"bufio"
	"bytes"
	"context"
	"crypto/sha1"
	"encoding/binary"
	"encoding/hex"
	"encoding/json"
	"errors"
	"fmt"
	"image"
	"image/color"
	"image/draw"
	"image/jpeg"
	"image/png"
	"io"
	"log"
	"math"
	"math/rand"
	"net/http"
	"net/url"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"regexp"
	"runtime"
	"sort"
	"strconv"
	"strings"
	"sync"
	"sync/atomic"
	"time"

	"github.com/grafov/m3u8"
	gocpu "github.com/shirou/gopsutil/v3/cpu"
	godisk "github.com/shirou/gopsutil/v3/disk"
	"golang.org/x/image/font"
	"golang.org/x/image/font/basicfont"
	"golang.org/x/image/math/fixed"
)

var roomDossierRegexp = regexp.MustCompile(`window\.initialRoomDossier = "(.*?)"`)

type JobStatus string

const (
	JobRunning  JobStatus = "running"
	JobPostwork JobStatus = "postwork" // ✅ NEU: Aufnahme vorbei, Nacharbeiten laufen noch
	JobFinished JobStatus = "finished"
	JobStopped  JobStatus = "stopped"
	JobFailed   JobStatus = "failed"
)

type RecordJob struct {
	ID              string     `json:"id"`
	SourceURL       string     `json:"sourceUrl"`
	Output          string     `json:"output"`
	Status          JobStatus  `json:"status"`
	StartedAt       time.Time  `json:"startedAt"`
	EndedAt         *time.Time `json:"endedAt,omitempty"`
	DurationSeconds float64    `json:"durationSeconds,omitempty"`
	SizeBytes       int64      `json:"sizeBytes,omitempty"`
	VideoWidth      int        `json:"videoWidth,omitempty"`
	VideoHeight     int        `json:"videoHeight,omitempty"`
	FPS             float64    `json:"fps,omitempty"`
	Meta            *videoMeta `json:"meta,omitempty"`

	Hidden bool `json:"-"`

	Error string `json:"error,omitempty"`

	PreviewDir       string    `json:"-"`
	PreviewImage     string    `json:"-"`
	previewCmd       *exec.Cmd `json:"-"`
	LiveThumbStarted bool      `json:"-"`

	// ✅ Preview-Status (z.B. private/offline anhand ffmpeg HTTP Fehler)
	PreviewState    string `json:"previewState,omitempty"`    // "", "private", "offline", "error"
	PreviewStateAt  string `json:"previewStateAt,omitempty"`  // RFC3339Nano
	PreviewStateMsg string `json:"previewStateMsg,omitempty"` // kurze Info

	// Thumbnail cache (verhindert, dass pro HTTP-Request ffmpeg läuft)
	previewMu     sync.Mutex `json:"-"`
	previewJpeg   []byte     `json:"-"`
	previewJpegAt time.Time  `json:"-"`
	previewGen    bool       `json:"-"`

	PreviewM3U8   string `json:"-"` // HLS url, die ffmpeg inputt
	PreviewCookie string `json:"-"` // Cookie header (falls nötig)
	PreviewUA     string `json:"-"` // user-agent

	previewCancel  context.CancelFunc `json:"-"`
	previewLastHit time.Time          `json:"-"`
	previewStartMu sync.Mutex         `json:"-"`

	// ✅ Frontend Progress beim Stop/Finalize
	Phase    string `json:"phase,omitempty"`    // stopping | remuxing | moving
	Progress int    `json:"progress,omitempty"` // 0..100

	PostWorkKey string             `json:"postWorkKey,omitempty"`
	PostWork    *PostWorkKeyStatus `json:"postWork,omitempty"`

	cancel context.CancelFunc `json:"-"`
}

type dummyResponseWriter struct {
	h http.Header
}

type ffprobeStreamInfo struct {
	Width        int    `json:"width"`
	Height       int    `json:"height"`
	AvgFrameRate string `json:"avg_frame_rate"`
	RFrameRate   string `json:"r_frame_rate"`
}

type ffprobeInfo struct {
	Streams []ffprobeStreamInfo `json:"streams"`
}

func parseFFRate(s string) float64 {
	s = strings.TrimSpace(s)
	if s == "" || s == "0/0" {
		return 0
	}
	// "30000/1001"
	if a, b, ok := strings.Cut(s, "/"); ok {
		num, err1 := strconv.ParseFloat(strings.TrimSpace(a), 64)
		den, err2 := strconv.ParseFloat(strings.TrimSpace(b), 64)
		if err1 == nil && err2 == nil && den != 0 {
			return num / den
		}
		return 0
	}
	// "25"
	f, err := strconv.ParseFloat(s, 64)
	if err != nil {
		return 0
	}
	return f
}

func probeVideoProps(ctx context.Context, filePath string) (w int, h int, fps float64, err error) {
	filePath = strings.TrimSpace(filePath)
	if filePath == "" {
		return 0, 0, 0, fmt.Errorf("empty path")
	}

	cmd := exec.CommandContext(ctx, ffprobePath,
		"-v", "error",
		"-select_streams", "v:0",
		"-show_entries", "stream=width,height,avg_frame_rate,r_frame_rate",
		"-of", "json",
		filePath,
	)

	out, err := cmd.Output()
	if err != nil {
		return 0, 0, 0, err
	}

	var info ffprobeInfo
	if err := json.Unmarshal(out, &info); err != nil {
		return 0, 0, 0, err
	}
	if len(info.Streams) == 0 {
		return 0, 0, 0, fmt.Errorf("no video stream")
	}

	s := info.Streams[0]
	w, h = s.Width, s.Height

	// bevorzugt avg_frame_rate, fallback r_frame_rate
	fps = parseFFRate(s.AvgFrameRate)
	if fps <= 0 {
		fps = parseFFRate(s.RFrameRate)
	}

	return w, h, fps, nil
}

func metaJSONPathForAssetID(assetID string) (string, error) {
	root, err := generatedMetaRoot()
	if err != nil {
		return "", err
	}
	if strings.TrimSpace(root) == "" {
		return "", fmt.Errorf("generated/meta root leer")
	}
	return filepath.Join(root, assetID, "meta.json"), nil
}

func readVideoMetaIfValid(metaPath string, fi os.FileInfo) (*videoMeta, bool) {
	b, err := os.ReadFile(metaPath)
	if err != nil || len(b) == 0 {
		return nil, false
	}
	var m videoMeta
	if err := json.Unmarshal(b, &m); err != nil {
		return nil, false
	}

	// nur akzeptieren wenn Datei identisch (damit wir nicht stale Werte zeigen)
	if m.FileSize != fi.Size() || m.FileModUnix != fi.ModTime().Unix() {
		return nil, false
	}

	// Mindestvalidierung
	if m.DurationSeconds <= 0 {
		return nil, false
	}

	return &m, true
}

func ensureVideoMetaForFile(ctx context.Context, fullPath string, fi os.FileInfo, sourceURL string) (*videoMeta, bool) {
	// assetID aus Dateiname
	stem := strings.TrimSuffix(filepath.Base(fullPath), filepath.Ext(fullPath))
	assetID := stripHotPrefix(strings.TrimSpace(stem))
	if assetID == "" {
		return nil, false
	}

	// sanitize wie bei deinen generated Ordnern
	var err error
	assetID, err = sanitizeID(assetID)
	if err != nil || assetID == "" {
		return nil, false
	}

	metaPath, err := metaJSONPathForAssetID(assetID)
	if err != nil {
		return nil, false
	}

	// 1) valid meta vorhanden?
	if m, ok := readVideoMetaIfValid(metaPath, fi); ok {
		return m, true
	}

	// 2) sonst neu erzeugen (mit Concurrency-Limit)
	if ctx == nil {
		ctx = context.Background()
	}
	cctx, cancel := context.WithTimeout(ctx, 8*time.Second)
	defer cancel()

	if durSem != nil {
		if err := durSem.Acquire(cctx); err != nil {
			return nil, false
		}
		defer durSem.Release()
	}

	// Dauer
	dur, derr := durationSecondsCached(cctx, fullPath)
	if derr != nil || dur <= 0 {
		return nil, false
	}

	// Video props
	w, h, fps, perr := probeVideoProps(cctx, fullPath)
	if perr != nil {
		// width/height/fps dürfen 0 bleiben, duration ist aber trotzdem nützlich
		w, h, fps = 0, 0, 0
	}

	// meta dir anlegen
	_ = os.MkdirAll(filepath.Dir(metaPath), 0o755)

	m := &videoMeta{
		Version:         2,
		DurationSeconds: dur,
		FileSize:        fi.Size(),
		FileModUnix:     fi.ModTime().Unix(),
		VideoWidth:      w,
		VideoHeight:     h,
		FPS:             fps,
		Resolution:      formatResolution(w, h),
		SourceURL:       strings.TrimSpace(sourceURL),
		UpdatedAtUnix:   time.Now().Unix(),
	}

	b, _ := json.MarshalIndent(m, "", "  ")
	b = append(b, '\n')
	_ = atomicWriteFile(metaPath, b) // best effort

	return m, true
}

// ensureVideoMetaForFileBestEffort:
//   - versucht zuerst echtes Generieren (ffprobe/ffmpeg) via ensureVideoMetaForFile
//   - wenn das fehlschlägt, aber durationSecondsCacheOnly schon was weiß:
//     schreibt eine Duration-only meta.json, damit wir künftig "aus meta.json" lesen können.
func ensureVideoMetaForFileBestEffort(ctx context.Context, fullPath string, sourceURL string) (*videoMeta, bool) {
	fullPath = strings.TrimSpace(fullPath)
	if fullPath == "" {
		return nil, false
	}

	fi, err := os.Stat(fullPath)
	if err != nil || fi == nil || fi.IsDir() || fi.Size() <= 0 {
		return nil, false
	}

	// 1) Normaler Weg: meta erzeugen/lesen (ffprobe/ffmpeg)
	if m, ok := ensureVideoMetaForFile(ctx, fullPath, fi, sourceURL); ok && m != nil {
		return m, true
	}

	// 2) Fallback: wenn wir Duration schon im RAM-Cache haben -> meta.json (Duration-only) persistieren
	dur := durationSecondsCacheOnly(fullPath, fi)
	if dur <= 0 {
		return nil, false
	}

	stem := strings.TrimSuffix(filepath.Base(fullPath), filepath.Ext(fullPath))
	assetID := stripHotPrefix(strings.TrimSpace(stem))
	if assetID == "" {
		return nil, false
	}

	metaPath, err := metaJSONPathForAssetID(assetID)
	if err != nil || strings.TrimSpace(metaPath) == "" {
		return nil, false
	}

	_ = os.MkdirAll(filepath.Dir(metaPath), 0o755)
	_ = writeVideoMetaDuration(metaPath, fi, dur, sourceURL)

	// nochmal lesen/validieren
	if m, ok := readVideoMetaIfValid(metaPath, fi); ok && m != nil {
		return m, true
	}

	return nil, false
}

func (d *dummyResponseWriter) Header() http.Header {
	if d.h == nil {
		d.h = make(http.Header)
	}
	return d.h
}
func (d *dummyResponseWriter) Write(b []byte) (int, error) { return len(b), nil }
func (d *dummyResponseWriter) WriteHeader(statusCode int)  {}

var (
	jobs   = map[string]*RecordJob{}
	jobsMu = sync.Mutex{}
)

var serverStartedAt = time.Now()

var lastCPUUsageBits uint64 // atomic float64 bits

func setLastCPUUsage(v float64) { atomic.StoreUint64(&lastCPUUsageBits, math.Float64bits(v)) }
func getLastCPUUsage() float64  { return math.Float64frombits(atomic.LoadUint64(&lastCPUUsageBits)) }

// -------------------- SSE: /api/record/stream --------------------

type sseHub struct {
	mu      sync.Mutex
	clients map[chan []byte]struct{}
}

func newSSEHub() *sseHub {
	return &sseHub{clients: map[chan []byte]struct{}{}}
}

func (h *sseHub) add(ch chan []byte) {
	h.mu.Lock()
	h.clients[ch] = struct{}{}
	h.mu.Unlock()
}

func (h *sseHub) remove(ch chan []byte) {
	h.mu.Lock()
	delete(h.clients, ch)
	h.mu.Unlock()
	close(ch)
}

func (h *sseHub) broadcast(b []byte) {
	h.mu.Lock()
	defer h.mu.Unlock()
	for ch := range h.clients {
		// Non-blocking: langsame Clients droppen Updates (holen sich beim nächsten Update wieder ein)
		select {
		case ch <- b:
		default:
		}
	}
}

var doneHub = newSSEHub()
var doneNotify = make(chan struct{}, 1)

// optional: monotoner Zähler, damit Clients auch bei "gleichen" payloads triggern können
var doneSeq uint64

func notifyDoneChanged() {
	select {
	case doneNotify <- struct{}{}:
	default:
	}
}

var recordJobsHub = newSSEHub()
var recordJobsNotify = make(chan struct{}, 1)

func startPreviewIdleKiller() {
	t := time.NewTicker(5 * time.Second)
	go func() {
		defer t.Stop()
		for range t.C {
			jobsMu.Lock()
			list := make([]*RecordJob, 0, len(jobs))
			for _, j := range jobs {
				if j != nil {
					list = append(list, j)
				}
			}
			jobsMu.Unlock()

			for _, j := range list {
				jobsMu.Lock()
				cmdRunning := j.previewCmd != nil
				last := j.previewLastHit
				st := j.Status
				jobsMu.Unlock()

				if !cmdRunning {
					continue
				}
				// wenn Job nicht mehr läuft oder Hover weg
				if st != JobRunning || (!last.IsZero() && time.Since(last) > 10*time.Minute) {
					stopPreview(j)
				}
			}
		}
	}()
}

func init() {
	initFFmpegSemaphores()
	startAdaptiveSemController(context.Background())
	startPreviewIdleKiller()

	// Debounced broadcaster (jobs)
	go func() {
		for range recordJobsNotify {
			time.Sleep(40 * time.Millisecond)
			for {
				select {
				case <-recordJobsNotify:
				default:
					goto SEND
				}
			}
		SEND:
			recordJobsHub.broadcast(jobsSnapshotJSON())
		}
	}()

	// Debounced broadcaster (done changed)
	go func() {
		for range doneNotify {
			time.Sleep(40 * time.Millisecond)
			for {
				select {
				case <-doneNotify:
				default:
					goto SEND
				}
			}
		SEND:
			seq := atomic.AddUint64(&doneSeq, 1)

			// Payload bewusst klein halten: Client soll nur "refetch done" machen
			b := []byte(fmt.Sprintf(`{"type":"doneChanged","seq":%d,"ts":%d}`, seq, time.Now().UnixMilli()))
			doneHub.broadcast(b)
		}
	}()
}

func publishJob(jobID string) bool {
	jobsMu.Lock()
	j := jobs[jobID]
	if j == nil || !j.Hidden {
		jobsMu.Unlock()
		return false
	}
	j.Hidden = false
	jobsMu.Unlock()

	notifyJobsChanged()
	return true
}

func notifyJobsChanged() {
	select {
	case recordJobsNotify <- struct{}{}:
	default:
	}
}

func jobsSnapshotJSON() []byte {
	jobsMu.Lock()
	list := make([]*RecordJob, 0, len(jobs))
	for _, j := range jobs {
		// ✅ Hidden-Jobs niemals an die UI senden (verhindert „UI springt“)
		if j == nil || j.Hidden {
			continue
		}

		c := *j
		c.cancel = nil // nicht serialisieren
		list = append(list, &c)
	}
	jobsMu.Unlock()

	// optional: neueste zuerst
	sort.Slice(list, func(i, j int) bool {
		return list[i].StartedAt.After(list[j].StartedAt)
	})

	b, _ := json.Marshal(list)
	return b
}

func recordStream(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.Error(w, "Nur GET erlaubt", http.StatusMethodNotAllowed)
		return
	}

	flusher, ok := w.(http.Flusher)
	if !ok {
		http.Error(w, "Streaming nicht unterstützt", http.StatusInternalServerError)
		return
	}

	// SSE-Header
	h := w.Header()
	h.Set("Content-Type", "text/event-stream; charset=utf-8")
	h.Set("Cache-Control", "no-cache, no-transform")
	h.Set("Connection", "keep-alive")
	h.Set("X-Accel-Buffering", "no") // hilfreich bei Reverse-Proxies

	// sofort starten
	w.WriteHeader(http.StatusOK)

	writeEvent := func(event string, data []byte) bool {
		// returns false => client weg / write error
		if event != "" {
			if _, err := fmt.Fprintf(w, "event: %s\n", event); err != nil {
				return false
			}
		}
		if len(data) > 0 {
			if _, err := fmt.Fprintf(w, "data: %s\n\n", data); err != nil {
				return false
			}
		} else {
			// empty payload ok (nur terminator)
			if _, err := io.WriteString(w, "\n"); err != nil {
				return false
			}
		}
		flusher.Flush()
		return true
	}

	writeComment := func(msg string) bool {
		if _, err := fmt.Fprintf(w, ": %s\n\n", msg); err != nil {
			return false
		}
		flusher.Flush()
		return true
	}

	// Reconnect-Hinweis
	if _, err := fmt.Fprintf(w, "retry: 3000\n\n"); err != nil {
		return
	}
	flusher.Flush()

	// Channel + Hub
	ch := make(chan []byte, 32)
	recordJobsHub.add(ch)
	defer recordJobsHub.remove(ch)

	// Initialer Snapshot sofort
	if b := jobsSnapshotJSON(); len(b) > 0 {
		if !writeEvent("jobs", b) {
			return
		}
	}

	ctx := r.Context()

	// Ping/Keepalive
	ping := time.NewTicker(15 * time.Second)
	defer ping.Stop()

	for {
		select {
		case <-ctx.Done():
			return

		case b, ok := <-ch:
			if !ok {
				return
			}
			if len(b) == 0 {
				continue
			}

			// ✅ Burst-Coalescing: wenn viele Updates schnell kommen, nur das neueste senden
			last := b
		drain:
			for i := 0; i < 64; i++ {
				select {
				case nb, ok := <-ch:
					if !ok {
						return
					}
					if len(nb) > 0 {
						last = nb
					}
				default:
					break drain
				}
			}

			if !writeEvent("jobs", last) {
				return
			}

		case <-ping.C:
			// Keepalive als Kommentar (stört nicht, hält Verbindungen offen)
			if !writeComment(fmt.Sprintf("ping %d", time.Now().Unix())) {
				return
			}
		}
	}
}

// ffmpeg-Binary suchen (env, neben EXE, oder PATH)
var ffmpegPath = detectFFmpegPath()

var ffprobePath = detectFFprobePath()

func detectFFprobePath() string {
	// 1) Env-Override
	if p := strings.TrimSpace(os.Getenv("FFPROBE_PATH")); p != "" {
		if abs, err := filepath.Abs(p); err == nil {
			return abs
		}
		return p
	}

	// 2) Neben ffmpeg.exe (gleicher Ordner)
	fp := strings.TrimSpace(ffmpegPath)
	if fp != "" && fp != "ffmpeg" {
		dir := filepath.Dir(fp)
		ext := ""
		if strings.HasSuffix(strings.ToLower(fp), ".exe") {
			ext = ".exe"
		}
		c := filepath.Join(dir, "ffprobe"+ext)
		if fi, err := os.Stat(c); err == nil && !fi.IsDir() {
			return c
		}
	}

	// 3) Im EXE-Ordner
	if exe, err := os.Executable(); err == nil {
		exeDir := filepath.Dir(exe)
		candidates := []string{
			filepath.Join(exeDir, "ffprobe"),
			filepath.Join(exeDir, "ffprobe.exe"),
		}
		for _, c := range candidates {
			if fi, err := os.Stat(c); err == nil && !fi.IsDir() {
				return c
			}
		}
	}

	// 4) PATH
	if lp, err := exec.LookPath("ffprobe"); err == nil {
		if abs, err2 := filepath.Abs(lp); err2 == nil {
			return abs
		}
		return lp
	}

	return "ffprobe"
}

// ---------- Dynamic Semaphore (resizeable by load controller) ----------

type DynSem struct {
	mu  sync.Mutex
	in  int
	max int
	cap int
}

func NewDynSem(initial, cap int) *DynSem {
	if cap < 1 {
		cap = 1
	}
	if initial < 1 {
		initial = 1
	}
	if initial > cap {
		initial = cap
	}
	return &DynSem{max: initial, cap: cap}
}

func (s *DynSem) Acquire(ctx context.Context) error {
	for {
		if ctx != nil && ctx.Err() != nil {
			return ctx.Err()
		}
		s.mu.Lock()
		if s.in < s.max {
			s.in++
			s.mu.Unlock()
			return nil
		}
		s.mu.Unlock()
		time.Sleep(25 * time.Millisecond)
	}
}

func (s *DynSem) Release() {
	s.mu.Lock()
	if s.in > 0 {
		s.in--
	}
	s.mu.Unlock()
}

func (s *DynSem) SetMax(n int) {
	if n < 1 {
		n = 1
	}
	if n > s.cap {
		n = s.cap
	}
	s.mu.Lock()
	s.max = n
	s.mu.Unlock()
}

func (s *DynSem) Max() int {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.max
}

func (s *DynSem) Cap() int {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.cap
}

func (s *DynSem) InUse() int {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.in
}

var (
	genSem     *DynSem
	previewSem *DynSem
	thumbSem   *DynSem
	durSem     *DynSem
)

func clamp(n, lo, hi int) int {
	if n < lo {
		return lo
	}
	if n > hi {
		return hi
	}
	return n
}

func envInt(name string) (int, bool) {
	v := strings.TrimSpace(os.Getenv(name))
	if v == "" {
		return 0, false
	}
	n, err := strconv.Atoi(v)
	if err != nil {
		return 0, false
	}
	return n, true
}

func initFFmpegSemaphores() {
	cpu := runtime.NumCPU()
	if cpu <= 0 {
		cpu = 2
	}

	// Defaults (heuristisch)
	previewN := clamp((cpu+1)/2, 1, 6) // x264 live -> konservativ
	thumbN := clamp(cpu, 2, 12)        // Frames -> darf höher
	genN := clamp((cpu+3)/4, 1, 4)     // preview.mp4 clips -> eher klein
	durN := clamp(cpu, 2, 16)          // ffprobe: darf höher, aber nicht unbegrenzt

	// ENV Overrides (optional)
	if n, ok := envInt("PREVIEW_WORKERS"); ok {
		previewN = clamp(n, 1, 32)
	}
	if n, ok := envInt("THUMB_WORKERS"); ok {
		thumbN = clamp(n, 1, 64)
	}
	if n, ok := envInt("GEN_WORKERS"); ok {
		genN = clamp(n, 1, 16)
	}
	if n, ok := envInt("DUR_WORKERS"); ok {
		durN = clamp(n, 1, 64)
	}

	// Caps (Obergrenzen) – können via ENV überschrieben werden
	previewCap := clamp(cpu, 2, 12)
	thumbCap := clamp(cpu*2, 4, 32)
	genCap := clamp((cpu+1)/2, 2, 12)
	durCap := clamp(cpu*2, 4, 32)

	if n, ok := envInt("PREVIEW_CAP"); ok {
		previewCap = clamp(n, 1, 64)
	}
	if n, ok := envInt("THUMB_CAP"); ok {
		thumbCap = clamp(n, 1, 128)
	}
	if n, ok := envInt("GEN_CAP"); ok {
		genCap = clamp(n, 1, 64)
	}
	if n, ok := envInt("DUR_CAP"); ok {
		durCap = clamp(n, 1, 128)
	}

	// Initial max (Startwerte)
	previewSem = NewDynSem(previewN, previewCap)
	thumbSem = NewDynSem(thumbN, thumbCap)
	genSem = NewDynSem(genN, genCap)
	durSem = NewDynSem(durN, durCap)

	fmt.Printf(
		"🔧 semaphores(init): preview=%d/%d thumb=%d/%d gen=%d/%d dur=%d/%d (cpu=%d)\n",
		previewSem.Max(), previewSem.Cap(),
		thumbSem.Max(), thumbSem.Cap(),
		genSem.Max(), genSem.Cap(),
		durSem.Max(), durSem.Cap(),
		cpu,
	)

	fmt.Printf(
		"🔧 semaphores: preview=%d thumb=%d gen=%d dur=%d (cpu=%d)\n",
		previewN, thumbN, genN, durN, cpu,
	)
}

func startAdaptiveSemController(ctx context.Context) {
	targetHi := 85.0
	targetLo := 65.0

	if v := strings.TrimSpace(os.Getenv("CPU_TARGET_HI")); v != "" {
		if f, err := strconv.ParseFloat(v, 64); err == nil {
			targetHi = f
		}
	}
	if v := strings.TrimSpace(os.Getenv("CPU_TARGET_LO")); v != "" {
		if f, err := strconv.ParseFloat(v, 64); err == nil {
			targetLo = f
		}
	}

	// Warmup (erste Messung kann 0 sein)
	_, _ = gocpu.Percent(200*time.Millisecond, false)

	t := time.NewTicker(2 * time.Second)
	go func() {
		defer t.Stop()

		for {
			select {
			case <-ctx.Done():
				return
			case <-t.C:
				p, err := gocpu.Percent(0, false)
				if err != nil || len(p) == 0 {
					continue
				}
				usage := p[0]
				setLastCPUUsage(usage)

				// Preview ist am teuersten → konservativ
				if usage > targetHi {
					previewSem.SetMax(previewSem.Max() - 1)
					genSem.SetMax(genSem.Max() - 1)
					thumbSem.SetMax(thumbSem.Max() - 1)
				} else if usage < targetLo {
					previewSem.SetMax(previewSem.Max() + 1)
					genSem.SetMax(genSem.Max() + 1)
					thumbSem.SetMax(thumbSem.Max() + 1)
				}

				// optional Debug:
				// fmt.Printf("CPU %.1f%% -> preview=%d thumb=%d gen=%d\n", usage, previewSem.Max(), thumbSem.Max(), genSem.Max())
			}
		}
	}()
}

type durEntry struct {
	size int64
	mod  time.Time
	sec  float64
}

var durCache = struct {
	mu sync.Mutex
	m  map[string]durEntry
}{m: map[string]durEntry{}}

var startedAtFromFilenameRe = regexp.MustCompile(
	`^(.+)_([0-9]{1,2})_([0-9]{1,2})_([0-9]{4})__([0-9]{1,2})-([0-9]{2})-([0-9]{2})$`,
)

func buildPerfSnapshot() map[string]any {
	var ms runtime.MemStats
	runtime.ReadMemStats(&ms)

	s := getSettings()
	recordDir, _ := resolvePathRelativeToApp(s.RecordDir)

	var diskFreeBytes uint64
	var diskTotalBytes uint64
	var diskUsedPercent float64
	diskPath := recordDir

	if recordDir != "" {
		if u, err := godisk.Usage(recordDir); err == nil && u != nil {
			diskFreeBytes = u.Free
			diskTotalBytes = u.Total
			diskUsedPercent = u.UsedPercent
		}
	}

	// ✅ Dynamische Disk-Schwellen (2× inFlight, Resume = +3GB)
	pauseGB, resumeGB, inFlight, pauseNeed, resumeNeed := computeDiskThresholds()

	resp := map[string]any{
		"ts":        time.Now().UTC().Format(time.RFC3339Nano),
		"serverMs":  time.Now().UTC().UnixMilli(), // ✅ für "Ping" im Frontend (Approx)
		"uptimeSec": time.Since(serverStartedAt).Seconds(),
		"cpuPercent": func() float64 {
			v := getLastCPUUsage()
			if math.IsNaN(v) || math.IsInf(v, 0) || v < 0 {
				return 0
			}
			return v
		}(),
		"diskPath":        diskPath,
		"diskFreeBytes":   diskFreeBytes,
		"diskTotalBytes":  diskTotalBytes,
		"diskUsedPercent": diskUsedPercent,
		"diskEmergency":   atomic.LoadInt32(&diskEmergency) == 1,

		// ✅ statt LowDiskPauseBelowGB aus Settings
		"diskPauseBelowGB":  pauseGB,
		"diskResumeAboveGB": resumeGB,

		// ✅ optional, aber sehr hilfreich (Debug/UI)
		"diskInFlightBytes":   inFlight,
		"diskInFlightHuman":   formatBytesSI(u64ToI64(inFlight)),
		"diskPauseNeedBytes":  pauseNeed,
		"diskPauseNeedHuman":  formatBytesSI(u64ToI64(pauseNeed)),
		"diskResumeNeedBytes": resumeNeed,
		"diskResumeNeedHuman": formatBytesSI(u64ToI64(resumeNeed)),

		"goroutines": runtime.NumGoroutine(),
		"mem": map[string]any{
			"alloc":     ms.Alloc,
			"heapAlloc": ms.HeapAlloc,
			"heapInuse": ms.HeapInuse,
			"sys":       ms.Sys,
			"numGC":     ms.NumGC,
		},
	}

	sem := map[string]any{}
	if genSem != nil {
		sem["gen"] = map[string]any{"inUse": genSem.InUse(), "cap": genSem.Cap(), "max": genSem.Max()}
	}
	if previewSem != nil {
		sem["preview"] = map[string]any{"inUse": previewSem.InUse(), "cap": previewSem.Cap(), "max": previewSem.Max()}
	}
	if thumbSem != nil {
		sem["thumb"] = map[string]any{"inUse": thumbSem.InUse(), "cap": thumbSem.Cap(), "max": thumbSem.Max()}
	}
	if durSem != nil {
		sem["dur"] = map[string]any{"inUse": durSem.InUse(), "cap": durSem.Cap(), "max": durSem.Max()}
	}
	if len(sem) > 0 {
		resp["sem"] = sem
	}

	return resp
}

func pingHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet && r.Method != http.MethodHead {
		http.Error(w, "Nur GET/HEAD erlaubt", http.StatusMethodNotAllowed)
		return
	}
	w.Header().Set("Cache-Control", "no-store")
	w.WriteHeader(http.StatusNoContent)
}

func perfHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.Error(w, "Nur GET erlaubt", http.StatusMethodNotAllowed)
		return
	}

	resp := buildPerfSnapshot()

	w.Header().Set("Content-Type", "application/json")
	w.Header().Set("Cache-Control", "no-store")
	_ = json.NewEncoder(w).Encode(resp)
}

func perfStreamHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.Error(w, "Nur GET erlaubt", http.StatusMethodNotAllowed)
		return
	}

	fl, ok := w.(http.Flusher)
	if !ok {
		http.Error(w, "Streaming nicht unterstützt", http.StatusInternalServerError)
		return
	}

	// Optional: client kann Intervall mitgeben: /api/perf/stream?ms=5000
	ms := 5000
	if q := r.URL.Query().Get("ms"); q != "" {
		if v, err := strconv.Atoi(q); err == nil {
			// clamp: 1000..30000
			if v < 1000 {
				v = 1000
			}
			if v > 30000 {
				v = 30000
			}
			ms = v
		}
	}

	w.Header().Set("Content-Type", "text/event-stream; charset=utf-8")
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Connection", "keep-alive")
	// hilfreich hinter nginx/proxies:
	w.Header().Set("X-Accel-Buffering", "no")

	ctx := r.Context()

	// sofort erstes Event schicken
	send := func() error {
		payload := buildPerfSnapshot()

		var buf bytes.Buffer
		if err := json.NewEncoder(&buf).Encode(payload); err != nil {
			return err
		}

		// event: perf
		_, _ = io.WriteString(w, "event: perf\n")
		_, _ = io.WriteString(w, "data: ")
		_, _ = w.Write(buf.Bytes())
		_, _ = io.WriteString(w, "\n")
		fl.Flush()
		return nil
	}

	// initial
	_ = send()

	t := time.NewTicker(time.Duration(ms) * time.Millisecond)
	hb := time.NewTicker(15 * time.Second) // heartbeat gegen Proxy timeouts
	defer t.Stop()
	defer hb.Stop()

	for {
		select {
		case <-ctx.Done():
			return
		case <-t.C:
			_ = send()
		case <-hb.C:
			// SSE Kommentar als Heartbeat
			_, _ = io.WriteString(w, ": keep-alive\n\n")
			fl.Flush()
		}
	}
}

// -------------------------
// Low disk space guard
//  - pausiert Autostart
//  - stoppt laufende Downloads
// -------------------------

const (
	diskGuardInterval = 5 * time.Second
)

var diskEmergency int32 // 0=false, 1=true

type diskStatusResp struct {
	Emergency      bool   `json:"emergency"`
	PauseGB        int    `json:"pauseGB"`
	ResumeGB       int    `json:"resumeGB"`
	FreeBytes      uint64 `json:"freeBytes"`
	FreeBytesHuman string `json:"freeBytesHuman"`
	RecordPath     string `json:"recordPath"`
}

func diskStatusHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet && r.Method != http.MethodHead {
		http.Error(w, "Nur GET/HEAD erlaubt", http.StatusMethodNotAllowed)
		return
	}

	s := getSettings()

	pauseGB, resumeGB, _, _, _ := computeDiskThresholds()

	recordDirAbs, _ := resolvePathRelativeToApp(s.RecordDir)
	dir := strings.TrimSpace(recordDirAbs)
	if dir == "" {
		dir = strings.TrimSpace(s.RecordDir)
	}

	free := uint64(0)
	if dir != "" {
		if u, err := godisk.Usage(dir); err == nil && u != nil {
			free = u.Free
		}
	}

	resp := diskStatusResp{
		Emergency:      atomic.LoadInt32(&diskEmergency) == 1,
		PauseGB:        pauseGB,
		ResumeGB:       resumeGB,
		FreeBytes:      free,
		FreeBytesHuman: formatBytesSI(int64(free)),
		RecordPath:     dir,
	}

	w.Header().Set("Cache-Control", "no-store")
	writeJSON(w, http.StatusOK, resp)
}

// stopJobsInternal markiert Jobs als "stopping" und cancelt sie (inkl. Preview-FFmpeg Kill).
// Nutzt 2 notify-Pushes, damit die UI Phase/Progress sofort sieht.
func stopJobsInternal(list []*RecordJob) {
	if len(list) == 0 {
		return
	}

	type payload struct {
		cmd    *exec.Cmd
		cancel context.CancelFunc
	}

	pl := make([]payload, 0, len(list))

	jobsMu.Lock()
	for _, job := range list {
		if job == nil {
			continue
		}
		job.Phase = "stopping"
		job.Progress = 10
		pl = append(pl, payload{cmd: job.previewCmd, cancel: job.cancel})
		job.previewCmd = nil
	}
	jobsMu.Unlock()

	notifyJobsChanged() // 1) UI sofort updaten (Phase/Progress)

	for _, p := range pl {
		if p.cmd != nil && p.cmd.Process != nil {
			_ = p.cmd.Process.Kill()
		}
		if p.cancel != nil {
			p.cancel()
		}
	}

	notifyJobsChanged() // 2) optional: nach Cancel/Kill nochmal pushen
}

func stopAllStoppableJobs() int {
	stoppable := make([]*RecordJob, 0, 16)

	jobsMu.Lock()
	for _, j := range jobs {
		if j == nil {
			continue
		}

		if j.Status != JobRunning {
			continue
		}

		phase := strings.ToLower(strings.TrimSpace(j.Phase))

		// ✅ Im Disk-Notfall ALLES stoppen, was noch schreibt.
		// Wir skippen nur Jobs, die sowieso schon im "stopping" sind.
		if phase == "stopping" {
			continue
		}

		stoppable = append(stoppable, j)
	}
	jobsMu.Unlock()

	stopJobsInternal(stoppable)
	return len(stoppable)
}

func shouldAutoDeleteSmallDownload(filePath string) (bool, int64, int64) {
	// returns: (shouldDelete, sizeBytes, thresholdBytes)

	s := getSettings()
	if !s.AutoDeleteSmallDownloads {
		return false, 0, 0
	}

	mb := s.AutoDeleteSmallDownloadsBelowMB
	if mb <= 0 {
		return false, 0, 0
	}

	p := strings.TrimSpace(filePath)
	if p == "" {
		return false, 0, 0
	}

	// relativ -> absolut versuchen (best effort)
	if !filepath.IsAbs(p) {
		if abs, err := resolvePathRelativeToApp(p); err == nil && strings.TrimSpace(abs) != "" {
			p = abs
		}
	}

	fi, err := os.Stat(p)
	if err != nil || fi.IsDir() {
		return false, 0, int64(mb) * 1024 * 1024
	}

	size := fi.Size()
	thr := int64(mb) * 1024 * 1024
	if size > 0 && size < thr {
		return true, size, thr
	}
	return false, size, thr
}

func sizeOfPathBestEffort(p string) uint64 {
	p = strings.TrimSpace(p)
	if p == "" {
		return 0
	}

	// relativ -> absolut versuchen
	if !filepath.IsAbs(p) {
		if abs, err := resolvePathRelativeToApp(p); err == nil && strings.TrimSpace(abs) != "" {
			p = abs
		}
	}

	fi, err := os.Stat(p)
	if err != nil || fi.IsDir() || fi.Size() <= 0 {
		return 0
	}
	return uint64(fi.Size())
}

func inFlightBytesForJob(j *RecordJob) uint64 {
	if j == nil {
		return 0
	}
	// Prefer live-tracked bytes if available (accurate & cheap).
	if j.SizeBytes > 0 {
		return uint64(j.SizeBytes)
	}
	return sizeOfPathBestEffort(j.Output)
}

const giB = uint64(1024 * 1024 * 1024)

// computeDiskThresholds:
// Pause = ceil( (2 * inFlightBytes) / GiB )
// Resume = Pause + 3 GB (Hysterese)
// Wenn inFlight==0 => Pause/Resume = 0
func computeDiskThresholds() (pauseGB int, resumeGB int, inFlight uint64, pauseNeed uint64, resumeNeed uint64) {
	inFlight = sumInFlightBytes()
	if inFlight == 0 {
		return 0, 0, 0, 0, 0
	}

	need := inFlight * 2
	pauseGB = int((need + giB - 1) / giB) // ceil

	// Safety cap (nur zur Sicherheit, falls irgendwas eskaliert)
	if pauseGB > 10_000 {
		pauseGB = 10_000
	}

	resumeGB = pauseGB + 3
	if resumeGB > 10_000 {
		resumeGB = 10_000
	}

	pauseNeed = uint64(pauseGB) * giB
	resumeNeed = uint64(resumeGB) * giB
	return
}

// ✅ Summe der "wachsenden" Daten (running + remuxing etc.)
// Idee: Für TS->MP4 Peak brauchst du grob nochmal die Größe der aktuellen Datei als Reserve.
func sumInFlightBytes() uint64 {
	var sum uint64

	jobsMu.Lock()
	defer jobsMu.Unlock()

	for _, j := range jobs {
		if j == nil {
			continue
		}
		if j.Status != JobRunning {
			continue
		}

		// Nimm die Datei, die gerade wächst.
		// In deinem System ist das typischerweise j.Output (TS oder temporäres Ziel).
		// Falls du ein separates Feld für "TempTS" o.ä. hast: hier ergänzen.
		sum += inFlightBytesForJob(j)
	}

	return sum
}

// startDiskSpaceGuard läuft im Backend und reagiert auch ohne offenen Browser.
// Bei wenig freiem Platz:
//   - Autostart pausieren
//   - laufende Jobs stoppen (nur Status=running und Phase leer)
func startDiskSpaceGuard() {
	t := time.NewTicker(diskGuardInterval)
	defer t.Stop()

	for range t.C {
		s := getSettings()

		// Pfad bestimmen, auf dem wir freien Speicher prüfen
		recordDirAbs, _ := resolvePathRelativeToApp(s.RecordDir)
		dir := strings.TrimSpace(recordDirAbs)
		if dir == "" {
			dir = strings.TrimSpace(s.RecordDir)
		}
		if dir == "" {
			continue
		}

		u, err := godisk.Usage(dir)
		if err != nil || u == nil {
			continue
		}
		free := u.Free

		// ✅ Dynamische Schwellen:
		// Pause = ceil((2 * inFlight) / GiB)
		// Resume = Pause + 3 GB
		// pauseNeed/resumeNeed sind die benötigten freien Bytes
		pauseGB, resumeGB, inFlight, pauseNeed, resumeNeed := computeDiskThresholds()

		// Wenn nichts läuft, gibt es nichts zu reservieren.
		// (Optional: Emergency zurücksetzen, damit Autostart wieder frei wird.)
		if inFlight == 0 {
			if atomic.LoadInt32(&diskEmergency) == 1 {
				atomic.StoreInt32(&diskEmergency, 0)
				fmt.Printf(
					"✅ [disk] No active jobs: emergency cleared (free=%s, path=%s)\n",
					formatBytesSI(u64ToI64(free)),
					dir,
				)
			}
			continue
		}

		// ✅ Hysterese: erst ab resumeNeed wieder "bereit"
		if atomic.LoadInt32(&diskEmergency) == 1 {
			if free >= resumeNeed {
				atomic.StoreInt32(&diskEmergency, 0)
				fmt.Printf(
					"✅ [disk] Recovered: free=%s (%dB) (>= %s, %dB) emergency cleared (pause=%dGB resume=%dGB inFlight=%s, %dB)\n",
					formatBytesSI(u64ToI64(free)), free,
					formatBytesSI(u64ToI64(resumeNeed)), resumeNeed,
					pauseGB, resumeGB,
					formatBytesSI(u64ToI64(inFlight)), inFlight,
				)
			}
			continue
		}

		// ✅ Normalzustand: solange free >= pauseNeed, nichts tun
		if free >= pauseNeed {
			continue
		}

		// ✅ Trigger: Notbremse aktivieren, Jobs stoppen
		atomic.StoreInt32(&diskEmergency, 1)
		fmt.Printf(
			"🛑 [disk] Low space: free=%s (%dB) (< %s, %dB, pause=%dGB resume=%dGB, inFlight=%s, %dB) -> stop jobs + block autostart via diskEmergency (path=%s)\n",
			formatBytesSI(u64ToI64(free)), free,
			formatBytesSI(u64ToI64(pauseNeed)), pauseNeed,
			pauseGB, resumeGB,
			formatBytesSI(u64ToI64(inFlight)), inFlight,
			dir,
		)

		stopped := stopAllStoppableJobs()
		if stopped > 0 {
			fmt.Printf("🛑 [disk] Stop requested for %d job(s)\n", stopped)
		}
	}
}

func setJobPhase(job *RecordJob, phase string, progress int) {
	if progress < 0 {
		progress = 0
	}
	if progress > 100 {
		progress = 100
	}

	jobsMu.Lock()
	job.Phase = phase
	job.Progress = progress
	jobsMu.Unlock()

	notifyJobsChanged()

}

func durationSecondsCached(ctx context.Context, path string) (float64, error) {
	fi, err := os.Stat(path)
	if err != nil {
		return 0, err
	}

	durCache.mu.Lock()
	if e, ok := durCache.m[path]; ok && e.size == fi.Size() && e.mod.Equal(fi.ModTime()) && e.sec > 0 {
		durCache.mu.Unlock()
		return e.sec, nil
	}
	durCache.mu.Unlock()

	// 1) ffprobe (bevorzugt)
	cmd := exec.CommandContext(ctx, ffprobePath,
		"-v", "error",
		"-show_entries", "format=duration",
		"-of", "default=noprint_wrappers=1:nokey=1",
		path,
	)
	out, err := cmd.Output()
	if err == nil {
		s := strings.TrimSpace(string(out))
		sec, err2 := strconv.ParseFloat(s, 64)
		if err2 == nil && sec > 0 {
			durCache.mu.Lock()
			durCache.m[path] = durEntry{size: fi.Size(), mod: fi.ModTime(), sec: sec}
			durCache.mu.Unlock()
			return sec, nil
		}
	}

	// 2) Fallback: ffmpeg -i "Duration: HH:MM:SS.xx" parsen
	cmd2 := exec.CommandContext(ctx, ffmpegPath, "-i", path)
	b, _ := cmd2.CombinedOutput() // ffmpeg liefert hier oft ExitCode!=0, Output ist trotzdem da
	text := string(b)

	re := regexp.MustCompile(`Duration:\s*(\d+):(\d+):(\d+(?:\.\d+)?)`)
	m := re.FindStringSubmatch(text)
	if len(m) != 4 {
		return 0, fmt.Errorf("duration not found")
	}
	hh, _ := strconv.ParseFloat(m[1], 64)
	mm, _ := strconv.ParseFloat(m[2], 64)
	ss, _ := strconv.ParseFloat(m[3], 64)
	sec := hh*3600 + mm*60 + ss
	if sec <= 0 {
		return 0, fmt.Errorf("invalid duration")
	}

	durCache.mu.Lock()
	durCache.m[path] = durEntry{size: fi.Size(), mod: fi.ModTime(), sec: sec}
	durCache.mu.Unlock()
	return sec, nil
}

func detectFFmpegPath() string {
	// 0. Settings-Override (ffmpegPath in recorder_settings.json / UI)
	s := getSettings()
	if p := strings.TrimSpace(s.FFmpegPath); p != "" {
		// Relativ zur EXE auflösen, falls nötig
		if !filepath.IsAbs(p) {
			if abs, err := resolvePathRelativeToApp(p); err == nil {
				p = abs
			}
		}
		return p
	}

	// 1. Umgebungsvariable FFMPEG_PATH erlaubt Override
	if p := strings.TrimSpace(os.Getenv("FFMPEG_PATH")); p != "" {
		if abs, err := filepath.Abs(p); err == nil {
			return abs
		}
		return p
	}

	// 2. ffmpeg / ffmpeg.exe im selben Ordner wie dein Go-Programm
	if exe, err := os.Executable(); err == nil {
		exeDir := filepath.Dir(exe)
		candidates := []string{
			filepath.Join(exeDir, "ffmpeg"),
			filepath.Join(exeDir, "ffmpeg.exe"),
		}
		for _, c := range candidates {
			if fi, err := os.Stat(c); err == nil && !fi.IsDir() {
				return c
			}
		}
	}

	// 3. ffmpeg über PATH suchen und absolut machen
	if lp, err := exec.LookPath("ffmpeg"); err == nil {
		if abs, err2 := filepath.Abs(lp); err2 == nil {
			return abs
		}
		return lp
	}

	// 4. Fallback: plain "ffmpeg" – kann dann immer noch fehlschlagen
	return "ffmpeg"
}

func removeGeneratedForID(id string) {
	// ✅ canonical id: wie beim Erzeugen der generated Ordner
	id = strings.TrimSpace(id)
	if id == "" {
		return
	}

	// falls jemand "file.mp4" übergibt
	id = strings.TrimSuffix(id, filepath.Ext(id))

	// HOT Prefix weg
	id = stripHotPrefix(id)

	// wichtig: exakt gleiche Normalisierung wie überall sonst (Ordnernamen!)
	var err error
	id, err = sanitizeID(id)
	if err != nil || id == "" {
		return
	}

	// 1) NEU: generated/meta/<id>/ ...
	if root, _ := generatedMetaRoot(); strings.TrimSpace(root) != "" {
		_ = os.RemoveAll(filepath.Join(root, id))
	}

	// (optional aber sinnvoll) 1b) Legacy: generated/<id>/ (falls noch alte Assets existieren)
	if root, _ := generatedRoot(); strings.TrimSpace(root) != "" {
		_ = os.RemoveAll(filepath.Join(root, id))
	}

	// 2) Temp Preview Segmente (HLS) wegräumen
	// (%TEMP%/rec_preview/<assetID>)
	_ = os.RemoveAll(filepath.Join(os.TempDir(), "rec_preview", id))

	// 3) Legacy Cleanup (best effort)
	thumbsLegacy, _ := generatedThumbsRoot()
	teaserLegacy, _ := generatedTeaserRoot()

	if strings.TrimSpace(thumbsLegacy) != "" {
		_ = os.RemoveAll(filepath.Join(thumbsLegacy, id))
		_ = os.Remove(filepath.Join(thumbsLegacy, id+".jpg"))
	}
	if strings.TrimSpace(teaserLegacy) != "" {
		_ = os.Remove(filepath.Join(teaserLegacy, id+".mp4"))
		_ = os.Remove(filepath.Join(teaserLegacy, id+"_teaser.mp4"))
	}
}

func purgeDurationCacheForPath(p string) {
	p = strings.TrimSpace(p)
	if p == "" {
		return
	}
	durCache.mu.Lock()
	delete(durCache.m, p)
	durCache.mu.Unlock()
}

func renameGenerated(oldID, newID string) {
	thumbsRoot, _ := generatedThumbsRoot()
	teaserRoot, _ := generatedTeaserRoot()

	oldThumb := filepath.Join(thumbsRoot, oldID)
	newThumb := filepath.Join(thumbsRoot, newID)
	if _, err := os.Stat(oldThumb); err == nil {
		if _, err2 := os.Stat(newThumb); os.IsNotExist(err2) {
			_ = os.Rename(oldThumb, newThumb)
		} else {
			_ = os.RemoveAll(oldThumb)
		}
	}

	oldTeaser := filepath.Join(teaserRoot, oldID+".mp4")
	newTeaser := filepath.Join(teaserRoot, newID+".mp4")
	if _, err := os.Stat(oldTeaser); err == nil {
		if _, err2 := os.Stat(newTeaser); os.IsNotExist(err2) {
			_ = os.Rename(oldTeaser, newTeaser)
		} else {
			_ = os.Remove(oldTeaser)
		}
	}
}

// --- Gemeinsame Status-Werte für MFC ---
type Status int

const (
	StatusUnknown Status = iota
	StatusPublic
	StatusPrivate
	StatusOffline
	StatusNotExist
)

func (s Status) String() string {
	switch s {
	case StatusPublic:
		return "PUBLIC"
	case StatusPrivate:
		return "PRIVATE"
	case StatusOffline:
		return "OFFLINE"
	case StatusNotExist:
		return "NOTEXIST"
	default:
		return "UNKNOWN"
	}
}

// HTTPClient kapselt http.Client + Header/Cookies (wie internal.Req im DVR)
type HTTPClient struct {
	client    *http.Client
	userAgent string
}

// gemeinsamen HTTP-Client erzeugen
func NewHTTPClient(userAgent string) *HTTPClient {
	if userAgent == "" {
		// Default, falls kein UA übergeben wird
		userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64)"
	}

	return &HTTPClient{
		client: &http.Client{
			Timeout: 10 * time.Second,
		},
		userAgent: userAgent,
	}
}

// Request-Erstellung mit User-Agent + Cookies
func (h *HTTPClient) NewRequest(ctx context.Context, method, url, cookieStr string) (*http.Request, error) {
	req, err := http.NewRequestWithContext(ctx, method, url, nil)
	if err != nil {
		return nil, err
	}

	// Basis-Header, die immer gesetzt werden
	if h.userAgent != "" {
		req.Header.Set("User-Agent", h.userAgent)
	} else {
		req.Header.Set("User-Agent", "Mozilla/5.0")
	}
	req.Header.Set("Accept", "*/*")

	// Cookie-String wie "name=value; foo=bar"
	addCookiesFromString(req, cookieStr)

	return req, nil
}

// Seite laden + einfache Erkennung von Schutzseiten (Cloudflare / Age-Gate)
func (h *HTTPClient) FetchPage(ctx context.Context, url, cookieStr string) (string, error) {
	req, err := h.NewRequest(ctx, http.MethodGet, url, cookieStr)
	if err != nil {
		return "", err
	}

	resp, err := h.client.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	data, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	body := string(data)

	// Etwas aussagekräftigere Fehler als nur "room dossier nicht gefunden"
	if strings.Contains(body, "<title>Just a moment...</title>") {
		return "", errors.New("Schutzseite von Cloudflare erhalten (\"Just a moment...\") – kein Room-HTML")
	}
	if strings.Contains(body, "Verify your age") {
		return "", errors.New("Altersverifikationsseite erhalten – kein Room-HTML")
	}

	if resp.StatusCode != http.StatusOK {
		return "", fmt.Errorf("HTTP %d beim Laden von %s", resp.StatusCode, url)
	}

	return body, nil
}

func remuxTSToMP4(tsPath, mp4Path string) error {
	// ffmpeg -y -i in.ts -c copy -movflags +faststart out.mp4
	cmd := exec.Command(ffmpegPath,
		"-y",
		"-i", tsPath,
		"-c", "copy",
		"-movflags", "+faststart",
		mp4Path,
	)
	var stderr bytes.Buffer
	cmd.Stderr = &stderr
	if err := cmd.Run(); err != nil {
		return fmt.Errorf("ffmpeg remux failed: %v (%s)", err, stderr.String())
	}
	return nil
}

func parseFFmpegOutTime(v string) float64 {
	v = strings.TrimSpace(v)
	if v == "" {
		return 0
	}
	parts := strings.Split(v, ":")
	if len(parts) != 3 {
		return 0
	}
	h, err1 := strconv.Atoi(parts[0])
	m, err2 := strconv.Atoi(parts[1])
	s, err3 := strconv.ParseFloat(parts[2], 64) // Sekunden können Dezimalstellen haben
	if err1 != nil || err2 != nil || err3 != nil {
		return 0
	}
	return float64(h*3600+m*60) + s
}

func remuxTSToMP4WithProgress(
	ctx context.Context,
	tsPath, mp4Path string,
	durationSec float64,
	inSize int64,
	onRatio func(r float64),
) error {
	// ffmpeg progress kommt auf stdout als key=value
	cmd := exec.CommandContext(ctx, ffmpegPath,
		"-y",
		"-nostats",
		"-progress", "pipe:1",
		"-i", tsPath,
		"-c", "copy",
		"-movflags", "+faststart",
		mp4Path,
	)

	stdout, err := cmd.StdoutPipe()
	if err != nil {
		return err
	}

	var stderr bytes.Buffer
	cmd.Stderr = &stderr

	if err := cmd.Start(); err != nil {
		return err
	}

	sc := bufio.NewScanner(stdout)
	sc.Buffer(make([]byte, 0, 64*1024), 1024*1024)

	var (
		lastOutSec  float64
		lastTotalSz int64
	)

	send := func(outSec float64, totalSize int64, force bool) {
		// bevorzugt: Zeit/Dauer
		if durationSec > 0 && outSec > 0 {
			r := outSec / durationSec
			if r < 0 {
				r = 0
			}
			if r > 1 {
				r = 1
			}
			if onRatio != nil {
				onRatio(r)
			}
			return
		}

		// fallback: Bytes (bei remux meist okay-ish)
		if inSize > 0 && totalSize > 0 {
			r := float64(totalSize) / float64(inSize)
			if r < 0 {
				r = 0
			}
			if r > 1 {
				r = 1
			}
			if onRatio != nil {
				onRatio(r)
			}
			return
		}

		// force (z.B. end)
		if force && onRatio != nil {
			onRatio(1)
		}
	}

	for sc.Scan() {
		line := strings.TrimSpace(sc.Text())
		if line == "" {
			continue
		}
		k, v, ok := strings.Cut(line, "=")
		if !ok {
			continue
		}

		switch k {
		case "out_time_us":
			if n, err := strconv.ParseInt(strings.TrimSpace(v), 10, 64); err == nil && n > 0 {
				lastOutSec = float64(n) / 1_000_000.0
				send(lastOutSec, lastTotalSz, false)
			}
		case "out_time_ms":
			if n, err := strconv.ParseInt(strings.TrimSpace(v), 10, 64); err == nil && n > 0 {
				// out_time_ms ist i.d.R. Millisekunden
				lastOutSec = float64(n) / 1_000.0
				send(lastOutSec, lastTotalSz, false)
			}
		case "out_time":
			if s := parseFFmpegOutTime(v); s > 0 {
				lastOutSec = s
				send(lastOutSec, lastTotalSz, false)
			}
		case "total_size":
			if n, err := strconv.ParseInt(strings.TrimSpace(v), 10, 64); err == nil && n > 0 {
				lastTotalSz = n
				send(lastOutSec, lastTotalSz, false)
			}
		case "progress":
			if strings.TrimSpace(v) == "end" {
				send(lastOutSec, lastTotalSz, true)
			}
		}
	}

	if err := cmd.Wait(); err != nil {
		return fmt.Errorf("ffmpeg remux failed: %v (%s)", err, strings.TrimSpace(stderr.String()))
	}
	return nil
}

// --- MP4 Streaming Optimierung (Fast Start) ---
// "Fast Start" bedeutet: moov vor mdat (Browser kann sofort Metadaten lesen)
func isFastStartMP4(path string) (bool, error) {
	f, err := os.Open(path)
	if err != nil {
		return false, err
	}
	defer f.Close()

	for i := 0; i < 256; i++ {
		var hdr [8]byte
		if _, err := io.ReadFull(f, hdr[:]); err != nil {
			// unklar/kurz -> nicht anfassen
			return true, nil
		}

		sz32 := binary.BigEndian.Uint32(hdr[0:4])
		typ := string(hdr[4:8])

		var boxSize int64
		headerSize := int64(8)

		if sz32 == 0 {
			return true, nil
		}
		if sz32 == 1 {
			var ext [8]byte
			if _, err := io.ReadFull(f, ext[:]); err != nil {
				return true, nil
			}
			boxSize = int64(binary.BigEndian.Uint64(ext[:]))
			headerSize = 16
		} else {
			boxSize = int64(sz32)
		}

		if boxSize < headerSize {
			return true, nil
		}

		switch typ {
		case "moov":
			return true, nil
		case "mdat":
			return false, nil
		}

		if _, err := f.Seek(boxSize-headerSize, io.SeekCurrent); err != nil {
			return true, nil
		}
	}

	return true, nil
}

func ensureFastStartMP4(path string) error {
	path = strings.TrimSpace(path)
	if path == "" || !strings.EqualFold(filepath.Ext(path), ".mp4") {
		return nil
	}
	if strings.TrimSpace(ffmpegPath) == "" {
		return nil
	}

	ok, err := isFastStartMP4(path)
	if err == nil && ok {
		return nil
	}

	dir := filepath.Dir(path)
	base := filepath.Base(path)
	tmp := filepath.Join(dir, ".__faststart__"+base+".tmp")
	bak := filepath.Join(dir, ".__faststart__"+base+".bak")

	_ = os.Remove(tmp)
	_ = os.Remove(bak)

	cmd := exec.Command(ffmpegPath,
		"-y",
		"-i", path,
		"-c", "copy",
		"-movflags", "+faststart",
		tmp,
	)

	var stderr bytes.Buffer
	cmd.Stderr = &stderr
	if err := cmd.Run(); err != nil {
		_ = os.Remove(tmp)
		return fmt.Errorf("ffmpeg faststart failed: %v (%s)", err, strings.TrimSpace(stderr.String()))
	}

	// atomar austauschen
	if err := os.Rename(path, bak); err != nil {
		_ = os.Remove(tmp)
		return fmt.Errorf("rename original to bak failed: %w", err)
	}
	if err := os.Rename(tmp, path); err != nil {
		_ = os.Rename(bak, path)
		_ = os.Remove(tmp)
		return fmt.Errorf("rename tmp to original failed: %w", err)
	}
	_ = os.Remove(bak)
	return nil
}

func extractLastFrameJPEG(path string) ([]byte, error) {
	cmd := exec.Command(
		ffmpegPath,
		"-hide_banner",
		"-loglevel", "error",
		"-sseof", "-0.1",
		"-i", path,
		"-frames:v", "1",
		"-vf", "scale=720:-2",
		"-q:v", "10",
		"-f", "image2pipe",
		"-vcodec", "mjpeg",
		"pipe:1",
	)

	var out bytes.Buffer
	var stderr bytes.Buffer
	cmd.Stdout = &out
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return nil, fmt.Errorf("ffmpeg last-frame: %w (%s)", err, strings.TrimSpace(stderr.String()))
	}
	return out.Bytes(), nil
}

func extractFrameAtTimeJPEG(path string, seconds float64) ([]byte, error) {
	if seconds < 0 {
		seconds = 0
	}
	seek := fmt.Sprintf("%.3f", seconds)

	cmd := exec.Command(
		ffmpegPath,
		"-hide_banner",
		"-loglevel", "error",
		"-ss", seek,
		"-i", path,
		"-frames:v", "1",
		"-vf", "scale=720:-2",
		"-q:v", "10",
		"-f", "image2pipe",
		"-vcodec", "mjpeg",
		"pipe:1",
	)

	var out bytes.Buffer
	var stderr bytes.Buffer
	cmd.Stdout = &out
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return nil, fmt.Errorf("ffmpeg frame-at-time: %w (%s)", err, strings.TrimSpace(stderr.String()))
	}
	return out.Bytes(), nil
}

func extractLastFrameJPEGScaled(path string, width int, q int) ([]byte, error) {
	if width <= 0 {
		width = 320
	}
	if q <= 0 {
		q = 14
	}

	// ffmpeg: letztes Frame, low-res
	cmd := exec.Command(
		ffmpegPath,
		"-hide_banner", "-loglevel", "error",
		"-sseof", "-0.25",
		"-i", path,
		"-frames:v", "1",
		"-vf", fmt.Sprintf("scale=%d:-2", width),
		"-q:v", strconv.Itoa(q),
		"-f", "image2pipe",
		"pipe:1",
	)

	var out bytes.Buffer
	var stderr bytes.Buffer
	cmd.Stdout = &out
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return nil, fmt.Errorf("ffmpeg last-frame scaled: %w (%s)", err, strings.TrimSpace(stderr.String()))
	}

	b := out.Bytes()
	if len(b) == 0 {
		return nil, fmt.Errorf("ffmpeg last-frame scaled: empty output")
	}
	return b, nil
}

func extractFirstFrameJPEGScaled(path string, width int, q int) ([]byte, error) {
	if width <= 0 {
		width = 320
	}
	if q <= 0 {
		q = 14
	}

	cmd := exec.Command(
		ffmpegPath,
		"-hide_banner", "-loglevel", "error",
		"-ss", "0",
		"-i", path,
		"-frames:v", "1",
		"-vf", fmt.Sprintf("scale=%d:-2", width),
		"-q:v", strconv.Itoa(q),
		"-f", "image2pipe",
		"pipe:1",
	)

	var out bytes.Buffer
	var stderr bytes.Buffer
	cmd.Stdout = &out
	cmd.Stderr = &stderr

	if err := cmd.Run(); err != nil {
		return nil, fmt.Errorf("ffmpeg first-frame scaled: %w (%s)", err, strings.TrimSpace(stderr.String()))
	}

	b := out.Bytes()
	if len(b) == 0 {
		return nil, fmt.Errorf("ffmpeg first-frame scaled: empty output")
	}
	return b, nil
}

func extractLastFrameFromPreviewDirThumb(previewDir string) ([]byte, error) {
	seg, err := latestPreviewSegment(previewDir)
	if err != nil {
		return nil, err
	}

	// low-res, notfalls fallback auf erstes Frame
	img, err := extractLastFrameJPEGScaled(seg, 320, 14)
	if err == nil && len(img) > 0 {
		return img, nil
	}
	return extractFirstFrameJPEGScaled(seg, 320, 14)
}

// sucht das "neueste" Preview-Segment (seg_low_XXXXX.ts / seg_hq_XXXXX.ts)
func latestPreviewSegment(previewDir string) (string, error) {
	entries, err := os.ReadDir(previewDir)
	if err != nil {
		return "", err
	}

	var best string
	for _, e := range entries {
		if e.IsDir() {
			continue
		}
		name := e.Name()
		if !strings.HasPrefix(name, "seg_low_") && !strings.HasPrefix(name, "seg_hq_") {
			continue
		}
		if best == "" || name > best {
			best = name
		}
	}

	if best == "" {
		return "", fmt.Errorf("kein Preview-Segment in %s", previewDir)
	}
	return filepath.Join(previewDir, best), nil
}

// erzeugt ein JPEG aus dem letzten Preview-Segment
func extractLastFrameFromPreviewDir(previewDir string) ([]byte, error) {
	seg, err := latestPreviewSegment(previewDir)
	if err != nil {
		return nil, err
	}

	// Segment ist klein und "fertig" – hier reicht ein Last-Frame-Versuch,
	// mit Fallback auf First-Frame.
	img, err := extractLastFrameJPEG(seg)
	if err != nil {
		return extractFirstFrameJPEG(seg)
	}
	return img, nil
}

func stripHotPrefix(s string) string {
	s = strings.TrimSpace(s)
	// akzeptiere "HOT " auch case-insensitive
	if len(s) >= 4 && strings.EqualFold(s[:4], "HOT ") {
		return strings.TrimSpace(s[4:])
	}
	return s
}

// --------------------------
// Covers: generated/covers/<category>.<ext>
// --------------------------

type coverInfo struct {
	Category    string `json:"category"`
	Model       string `json:"model,omitempty"`
	Src         string `json:"src,omitempty"`
	GeneratedAt string `json:"generatedAt"`
}

func normalizeCoverSrc(s string) string {
	s = strings.TrimSpace(s)
	if s == "" {
		return ""
	}
	// Windows -> URL-artig
	s2 := strings.ReplaceAll(s, "\\", "/")

	// Wenn es schon wie ein Web-Pfad aussieht, so lassen
	if strings.HasPrefix(s2, "/generated/") || strings.HasPrefix(s2, "http://") || strings.HasPrefix(s2, "https://") {
		return s2
	}

	// Wenn es ein lokaler Pfad ist, versuche den /generated/ Teil zu extrahieren
	// z.B. ".../generated/meta/<id>/thumbs.jpg" -> "/generated/meta/<id>/thumbs.jpg"
	if i := strings.Index(s2, "/generated/"); i >= 0 {
		return s2[i:]
	}
	return s2
}

func coverInfoPathForKey(key string) (string, error) {
	root, err := coversRoot()
	if err != nil {
		return "", err
	}
	return filepath.Join(root, key+".info.json"), nil
}

func writeCoverInfoBestEffort(key string, info coverInfo) {
	p, err := coverInfoPathForKey(key)
	if err != nil {
		return
	}

	b, err := json.MarshalIndent(info, "", "  ")
	if err != nil {
		return
	}
	_ = os.MkdirAll(filepath.Dir(p), 0o755)
	_ = os.WriteFile(p, b, 0o644)
}

func readCoverInfoBestEffort(key string) (coverInfo, bool) {
	p, err := coverInfoPathForKey(key)
	if err != nil {
		return coverInfo{}, false
	}
	b, err := os.ReadFile(p)
	if err != nil || len(b) == 0 {
		return coverInfo{}, false
	}
	var ci coverInfo
	if json.Unmarshal(b, &ci) != nil {
		return coverInfo{}, false
	}
	return ci, true
}

func drawLabel(img draw.Image, text string) {
	text = strings.TrimSpace(text)
	if text == "" {
		return
	}

	face := basicfont.Face7x13

	// Layout
	const margin = 10
	const padX = 10
	const padY = 8

	b := img.Bounds()

	// Max. verfügbare Breite für Text (ohne Padding/Margins)
	maxTextW := (b.Dx() - 2*margin) - 2*padX
	if maxTextW <= 0 {
		return
	}

	// Text ggf. kürzen, damit er ins Badge passt
	measure := func(s string) int {
		d := &font.Drawer{Face: face}
		return d.MeasureString(s).Ceil()
	}

	label := text
	if w := measure(label); w > maxTextW {
		ellipsis := "…"
		rs := []rune(text)

		// harte Schranke gegen Extremfälle
		if len(rs) == 0 {
			return
		}

		lo, hi := 0, len(rs)
		best := ""
		for lo <= hi {
			mid := (lo + hi) / 2
			cand := string(rs[:mid]) + ellipsis
			if measure(cand) <= maxTextW {
				best = cand
				lo = mid + 1
			} else {
				hi = mid - 1
			}
		}

		if best == "" {
			// notfalls nur Ellipsis
			label = ellipsis
		} else {
			label = best
		}
	}

	// Textmetriken
	d := &font.Drawer{Face: face}
	textW := d.MeasureString(label).Ceil()
	textH := face.Metrics().Height.Ceil()
	ascent := face.Metrics().Ascent.Ceil()

	// Badge-Box (unten links)
	x0 := b.Min.X + margin
	y1 := b.Max.Y - margin
	y0 := y1 - (textH + 2*padY)
	x1 := x0 + (textW + 2*padX)

	// Clamp nach rechts (falls Bild sehr schmal)
	maxX1 := b.Max.X - margin
	if x1 > maxX1 {
		shift := x1 - maxX1
		x0 -= shift
		x1 -= shift
		if x0 < b.Min.X+margin {
			x0 = b.Min.X + margin
			x1 = maxX1
		}
	}

	// Clamp nach oben (falls Bild sehr niedrig)
	minY0 := b.Min.Y + margin
	if y0 < minY0 {
		y0 = minY0
		y1 = y0 + (textH + 2*padY)
		if y1 > b.Max.Y-margin {
			// zu wenig Platz insgesamt
			return
		}
	}

	rect := image.Rect(x0, y0, x1, y1)

	// Background
	bg := image.NewUniform(color.RGBA{0, 0, 0, 170})
	draw.Draw(img, rect, bg, image.Point{}, draw.Over)

	// Optional: dünner Rand für mehr Kontrast
	border := image.NewUniform(color.RGBA{255, 255, 255, 35})
	// top
	draw.Draw(img, image.Rect(rect.Min.X, rect.Min.Y, rect.Max.X, rect.Min.Y+1), border, image.Point{}, draw.Over)
	// bottom
	draw.Draw(img, image.Rect(rect.Min.X, rect.Max.Y-1, rect.Max.X, rect.Max.Y), border, image.Point{}, draw.Over)
	// left
	draw.Draw(img, image.Rect(rect.Min.X, rect.Min.Y, rect.Min.X+1, rect.Max.Y), border, image.Point{}, draw.Over)
	// right
	draw.Draw(img, image.Rect(rect.Max.X-1, rect.Min.Y, rect.Max.X, rect.Max.Y), border, image.Point{}, draw.Over)

	// Text baseline
	tx := x0 + padX
	ty := y0 + padY + ascent

	// Mini-Schatten (Lesbarkeit)
	shadow := &font.Drawer{
		Dst:  img,
		Src:  image.NewUniform(color.RGBA{0, 0, 0, 200}),
		Face: face,
		Dot:  fixed.P(tx+1, ty+1),
	}
	shadow.DrawString(label)

	// Text
	fg := &font.Drawer{
		Dst:  img,
		Src:  image.NewUniform(color.RGBA{255, 255, 255, 235}),
		Face: face,
		Dot:  fixed.P(tx, ty),
	}
	fg.DrawString(label)
}

func splitTagsLoose(raw string) []string {
	raw = strings.TrimSpace(raw)
	if raw == "" {
		return nil
	}
	parts := strings.FieldsFunc(raw, func(r rune) bool {
		switch r {
		case '\n', ',', ';', '|':
			return true
		}
		return false
	})
	out := make([]string, 0, len(parts))
	seen := map[string]struct{}{}
	for _, p := range parts {
		t := strings.TrimSpace(p)
		if t == "" {
			continue
		}
		low := strings.ToLower(t)
		if _, ok := seen[low]; ok {
			continue
		}
		seen[low] = struct{}{}
		out = append(out, t)
	}
	return out
}

func hasTag(tagsRaw string, want string) bool {
	want = strings.ToLower(strings.TrimSpace(want))
	if want == "" {
		return false
	}
	for _, t := range splitTagsLoose(tagsRaw) {
		if strings.ToLower(strings.TrimSpace(t)) == want {
			return true
		}
	}
	return false
}

// ✅ Passe diese Struct/Methoden an dein echtes ModelStore-API an.
type coverModel struct {
	Key  string // z.B. model key/name
	Tags string // raw tags (csv/newline/…)
}

func listModelsForCovers() ([]coverModel, error) {
	if coverModelStore == nil {
		return nil, fmt.Errorf("model store not set")
	}

	ms := coverModelStore.List() // ✅ existiert bei dir

	out := make([]coverModel, 0, len(ms))
	for _, m := range ms {
		key := strings.TrimSpace(m.ModelKey)
		if key == "" {
			continue
		}
		out = append(out, coverModel{
			Key:  key,
			Tags: m.Tags,
		})
	}
	return out, nil
}

func pickRandomThumbForCategory(ctx context.Context, category string) (thumbPath string, err error) {
	category = strings.TrimSpace(category)
	if category == "" {
		return "", fmt.Errorf("category empty")
	}

	// Optional: früh abbrechen, wenn Request schon tot ist
	select {
	case <-ctx.Done():
		return "", ctx.Err()
	default:
	}

	models, err := listModelsForCovers()
	if err != nil {
		return "", err
	}

	// 1) Kandidaten-Models nach Tag filtern
	cands := make([]coverModel, 0, 64)
	for _, m := range models {
		key := strings.TrimSpace(m.Key)
		if key == "" {
			continue
		}
		if hasTag(m.Tags, category) {
			cands = append(cands, coverModel{Key: key, Tags: m.Tags})
		}
	}
	if len(cands) == 0 {
		return "", fmt.Errorf("no model with tag")
	}

	// 2) Kandidaten mischen und nacheinander probieren (robuster als 1 random pick)
	rand.Shuffle(len(cands), func(i, j int) { cands[i], cands[j] = cands[j], cands[i] })

	// 3) done dirs (einmalig auflösen)
	s := getSettings()
	doneAbs, derr := resolvePathRelativeToApp(s.DoneDir)
	if derr != nil || strings.TrimSpace(doneAbs) == "" {
		return "", fmt.Errorf("doneDir resolve failed: %v", derr)
	}

	type candFile struct {
		videoPath string
		id        string
	}

	isVideo := func(name string) bool {
		low := strings.ToLower(name)
		if strings.Contains(low, ".part") || strings.Contains(low, ".tmp") {
			return false
		}
		ext := strings.ToLower(filepath.Ext(name))
		return ext == ".mp4" || ext == ".ts"
	}

	// 4) Für jedes passende Model: Dateien sammeln, random wählen, Thumb prüfen
	for _, m := range cands {
		// Context check pro Iteration
		select {
		case <-ctx.Done():
			return "", ctx.Err()
		default:
		}

		modelKey := strings.TrimSpace(m.Key)
		if modelKey == "" {
			continue
		}

		// Kandidaten: done/<model>/ und done/keep/<model>/
		dirs := []string{
			filepath.Join(doneAbs, modelKey),
			filepath.Join(doneAbs, "keep", modelKey),
		}

		files := make([]candFile, 0, 128)

		for _, d := range dirs {
			ents, err := os.ReadDir(d)
			if err != nil {
				continue
			}
			for _, e := range ents {
				if e.IsDir() {
					continue
				}
				name := e.Name()
				if !isVideo(name) {
					continue
				}
				full := filepath.Join(d, name)
				stem := strings.TrimSuffix(name, filepath.Ext(name))
				id := stripHotPrefix(strings.TrimSpace(stem))
				if id == "" {
					continue
				}
				files = append(files, candFile{videoPath: full, id: id})
			}
		}

		if len(files) == 0 {
			// ✅ dieses Model hat (noch) keine Downloads -> nächstes Model probieren
			continue
		}

		// random file innerhalb des Models
		cf := files[rand.Intn(len(files))]

		// thumbs sicherstellen (best effort)
		_ = ensureAssetsForVideo(cf.videoPath)

		tp, terr := generatedThumbFile(cf.id)
		if terr != nil {
			// nächstes Model probieren
			continue
		}
		if fi, serr := os.Stat(tp); serr == nil && !fi.IsDir() && fi.Size() > 0 {
			return tp, nil
		}

		// ✅ Thumb fehlt -> nächstes Model probieren
	}

	return "", fmt.Errorf("no downloads/thumbs for category")
}

func coversRoot() (string, error) {
	return resolvePathRelativeToApp(filepath.Join("generated", "covers"))
}

func ensureCoversDir() (string, error) {
	root, err := coversRoot()
	if err != nil {
		return "", err
	}
	if strings.TrimSpace(root) == "" {
		return "", fmt.Errorf("covers root ist leer")
	}
	if err := os.MkdirAll(root, 0o755); err != nil {
		return "", err
	}
	return root, nil
}

var coverKeyRe = regexp.MustCompile(`[^a-z0-9._-]+`)

func sanitizeCoverKey(category string) (string, error) {
	c := strings.ToLower(strings.TrimSpace(category))

	if c == "" {
		sum := sha1.Sum([]byte(category))
		c = "tag_" + hex.EncodeToString(sum[:8]) // 16 hex chars reichen
	}

	if c == "" {
		return "", fmt.Errorf("category fehlt")
	}
	// Windows & FS safe
	c = strings.ReplaceAll(c, " ", "_")
	c = coverKeyRe.ReplaceAllString(c, "_")
	c = strings.Trim(c, "._-")
	if c == "" {
		return "", fmt.Errorf("category ungültig")
	}
	if len(c) > 120 {
		c = c[:120]
	}
	return c, nil
}

func detectImageExt(contentType string, b []byte) (ext string, ct string) {
	ct = strings.ToLower(strings.TrimSpace(contentType))

	// wenn server CT liefert
	switch {
	case strings.Contains(ct, "image/jpeg") || strings.Contains(ct, "image/jpg"):
		return ".jpg", "image/jpeg"
	case strings.Contains(ct, "image/png"):
		return ".png", "image/png"
	case strings.Contains(ct, "image/webp"):
		return ".webp", "image/webp"
	case strings.Contains(ct, "image/gif"):
		return ".gif", "image/gif"
	}

	// Magic bytes fallback
	if len(b) >= 3 && b[0] == 0xFF && b[1] == 0xD8 && b[2] == 0xFF {
		return ".jpg", "image/jpeg"
	}
	if len(b) >= 8 && bytes.Equal(b[:8], []byte{0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A}) {
		return ".png", "image/png"
	}
	if len(b) >= 12 && string(b[:4]) == "RIFF" && string(b[8:12]) == "WEBP" {
		return ".webp", "image/webp"
	}
	if len(b) >= 6 && (string(b[:6]) == "GIF87a" || string(b[:6]) == "GIF89a") {
		return ".gif", "image/gif"
	}

	// default: jpg
	return ".jpg", "image/jpeg"
}

func coverPathForCategory(key string, ext string) (string, error) {
	root, err := coversRoot()
	if err != nil {
		return "", err
	}
	if strings.TrimSpace(root) == "" {
		return "", fmt.Errorf("covers root ist leer")
	}
	if ext == "" {
		ext = ".jpg"
	}
	return filepath.Join(root, key+ext), nil
}

func findExistingCoverFile(key string) (string, os.FileInfo, bool) {
	root, err := coversRoot()
	if err != nil || strings.TrimSpace(root) == "" {
		return "", nil, false
	}
	// probiere gängige Endungen
	exts := []string{".jpg", ".png", ".webp", ".gif"}
	for _, ext := range exts {
		p := filepath.Join(root, key+ext)
		if fi, err := os.Stat(p); err == nil && !fi.IsDir() && fi.Size() > 0 {
			return p, fi, true
		}
	}
	return "", nil, false
}

func downloadBytes(ctx context.Context, rawURL string, ua string) ([]byte, string, error) {
	rawURL = strings.TrimSpace(rawURL)
	if rawURL == "" {
		return nil, "", fmt.Errorf("src fehlt")
	}

	// ✅ 1) Lokaler Pfad: nur /generated/... erlauben
	if strings.HasPrefix(rawURL, "/") {
		// URL-Pfad normalisieren und Traversal verhindern
		clean := path.Clean(rawURL) // URL-style cleaning
		if !strings.HasPrefix(clean, "/generated/") {
			return nil, "", fmt.Errorf("src ungültig")
		}
		if strings.Contains(clean, "..") {
			return nil, "", fmt.Errorf("src ungültig")
		}

		// "/generated/..." -> "generated/..." (relativ zur App)
		rel := strings.TrimPrefix(clean, "/")
		abs, err := resolvePathRelativeToApp(rel)
		if err != nil || strings.TrimSpace(abs) == "" {
			return nil, "", fmt.Errorf("src ungültig")
		}

		f, err := os.Open(abs)
		if err != nil {
			return nil, "", fmt.Errorf("download failed: %v", err)
		}
		defer f.Close()

		// max 10MB lesen
		b, err := io.ReadAll(io.LimitReader(f, 10*1024*1024))
		if err != nil {
			return nil, "", fmt.Errorf("download failed: %v", err)
		}
		if len(b) == 0 {
			return nil, "", fmt.Errorf("download empty")
		}

		// Content-Type grob nach Extension (Magic-bytes macht detectImageExt später sowieso)
		ext := strings.ToLower(filepath.Ext(abs))
		ct := "application/octet-stream"
		switch ext {
		case ".jpg", ".jpeg":
			ct = "image/jpeg"
		case ".png":
			ct = "image/png"
		case ".webp":
			ct = "image/webp"
		case ".gif":
			ct = "image/gif"
		}

		return b, ct, nil
	}

	// ✅ 2) Remote URL: wie bisher nur http/https
	u, err := url.Parse(rawURL)
	if err != nil || u.Scheme == "" || u.Host == "" {
		return nil, "", fmt.Errorf("src ungültig")
	}
	if u.Scheme != "http" && u.Scheme != "https" {
		return nil, "", fmt.Errorf("src schema nicht erlaubt")
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodGet, rawURL, nil)
	if err != nil {
		return nil, "", err
	}
	if strings.TrimSpace(ua) == "" {
		ua = "Mozilla/5.0"
	}
	req.Header.Set("User-Agent", ua)
	req.Header.Set("Accept", "image/*,*/*;q=0.8")

	client := &http.Client{Timeout: 12 * time.Second}
	resp, err := client.Do(req)
	if err != nil {
		return nil, "", err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, "", fmt.Errorf("download failed: HTTP %d", resp.StatusCode)
	}

	b, err := io.ReadAll(io.LimitReader(resp.Body, 10*1024*1024)) // max 10MB
	if err != nil {
		return nil, "", err
	}
	if len(b) == 0 {
		return nil, "", fmt.Errorf("download empty")
	}

	return b, resp.Header.Get("Content-Type"), nil
}

func generatedRoot() (string, error) {
	return resolvePathRelativeToApp("generated")
}

func generatedMetaRoot() (string, error) {
	return resolvePathRelativeToApp(filepath.Join("generated", "meta"))
}

// Legacy (falls noch alte Assets liegen):
func generatedThumbsRoot() (string, error) {
	return resolvePathRelativeToApp(filepath.Join("generated", "thumbs"))
}
func generatedTeaserRoot() (string, error) {
	return resolvePathRelativeToApp(filepath.Join("generated", "teaser"))
}

// irgendwo auf Package-Level (z.B. in derselben Datei über generatedCover)

var coverBatchMu sync.Mutex

var (
	coverBatchInflight int
	coverBatchStarted  time.Time

	coverBatchTotal     int
	coverBatchForced    int
	coverBatchMiss      int
	coverBatchErrors    int
	coverBatchNoThumb   int
	coverBatchDecodeErr int
)

func coverBatchEnter(force bool) {
	coverBatchMu.Lock()
	defer coverBatchMu.Unlock()

	if coverBatchInflight == 0 {
		coverBatchStarted = time.Now()
		coverBatchTotal = 0
		coverBatchForced = 0
		coverBatchMiss = 0
		coverBatchErrors = 0
		coverBatchNoThumb = 0
		coverBatchDecodeErr = 0

		log.Printf("[cover] BATCH START")
	}

	coverBatchInflight++
	coverBatchTotal++
	if force {
		coverBatchForced++
	} else {
		coverBatchMiss++
	}
}

func coverBatchLeave(outcome string, status int) {
	coverBatchMu.Lock()
	defer coverBatchMu.Unlock()

	// Outcome-Stats (grob, aber hilfreich)
	if status >= 400 {
		coverBatchErrors++
	}
	switch outcome {
	case "no-thumb":
		coverBatchNoThumb++
	case "decode-failed-no-overlay":
		coverBatchDecodeErr++
	}

	coverBatchInflight--
	if coverBatchInflight <= 0 {
		dur := time.Since(coverBatchStarted).Round(time.Millisecond)
		log.Printf(
			"[cover] BATCH END total=%d miss=%d forced=%d errors=%d noThumb=%d decodeFail=%d took=%s",
			coverBatchTotal,
			coverBatchMiss,
			coverBatchForced,
			coverBatchErrors,
			coverBatchNoThumb,
			coverBatchDecodeErr,
			dur,
		)

		coverBatchInflight = 0
	}
}

// ----------------------------------------------------------------------
// deine Handler-Funktion (vollständig)

var (
	reModelFromStem = regexp.MustCompile(`^(.*?)_\d{1,2}_\d{1,2}_\d{4}__\d{1,2}-\d{2}-\d{2}`)
)

// stem ist z.B. "sigmasian_01_21_2026__07-28-13" oder ein Parent-Dir-Name
func inferModelFromStem(stem string) string {
	stem = stripHotPrefix(strings.TrimSpace(stem))
	if stem == "" {
		return ""
	}
	m := reModelFromStem.FindStringSubmatch(stem)
	if len(m) >= 2 {
		return strings.TrimSpace(m[1])
	}
	return ""
}

// akzeptiert:
// - "/generated/meta/<id>/thumbs.jpg"
// - "C:\...\generated\meta\<id>\thumbs.jpg"
// - "http(s)://host/generated/meta/<id>/thumbs.jpg"
// - (fallback) irgendeinen Dateinamen-Stem, der wie "<model>_MM_DD_YYYY__HH-MM-ss" aussieht
func inferModelFromThumbLike(srcOrPath string) string {
	s := strings.TrimSpace(srcOrPath)
	if s == "" {
		return ""
	}

	// Windows -> slash
	s = strings.ReplaceAll(s, `\`, `/`)

	// Wenn URL: nimm nur den Path
	if u, err := url.Parse(s); err == nil && u != nil && u.Scheme != "" && u.Host != "" {
		s = u.Path
	}

	// Wenn es wie ".../<id>/thumbs.jpg" aussieht: parent dir ist <id>
	base := path.Base(s)
	lb := strings.ToLower(base)
	if strings.HasPrefix(lb, "thumbs.") {
		id := path.Base(path.Dir(s))
		return inferModelFromStem(id)
	}

	// Fallback: versuch Stem aus basename
	stem := strings.TrimSuffix(base, path.Ext(base))
	return inferModelFromStem(stem)
}

// ----------------------------------------------------------------------
// deine Handler-Funktion (vollständig)

type coverInfoListItem struct {
	Category    string `json:"category"`
	Model       string `json:"model,omitempty"`
	GeneratedAt string `json:"generatedAt,omitempty"`
	HasCover    bool   `json:"hasCover"`
}

func generatedCoverInfoList(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet && r.Method != http.MethodHead {
		http.Error(w, "Nur GET/HEAD erlaubt", http.StatusMethodNotAllowed)
		return
	}

	root, err := coversRoot()
	if err != nil {
		http.Error(w, "covers root: "+err.Error(), http.StatusInternalServerError)
		return
	}

	entries, err := os.ReadDir(root)
	if err != nil {
		http.Error(w, "covers dir: "+err.Error(), http.StatusInternalServerError)
		return
	}

	byKey := map[string]*coverInfoListItem{}

	ensure := func(key string) *coverInfoListItem {
		if v, ok := byKey[key]; ok {
			return v
		}
		v := &coverInfoListItem{Category: key}
		byKey[key] = v
		return v
	}

	isCoverExt := func(ext string) bool {
		switch strings.ToLower(ext) {
		case ".jpg", ".jpeg", ".png", ".webp", ".gif":
			return true
		default:
			return false
		}
	}

	for _, e := range entries {
		name := e.Name()
		lower := strings.ToLower(name)

		// info.json
		if strings.HasSuffix(lower, ".info.json") {
			key := strings.TrimSuffix(name, ".info.json")
			if ci, ok := readCoverInfoBestEffort(key); ok {
				v := ensure(key)
				if strings.TrimSpace(ci.Category) != "" {
					v.Category = strings.TrimSpace(ci.Category)
				}
				if strings.TrimSpace(ci.Model) != "" {
					v.Model = strings.TrimSpace(ci.Model)
				}
				if strings.TrimSpace(ci.GeneratedAt) != "" {
					v.GeneratedAt = strings.TrimSpace(ci.GeneratedAt)
				}
			}
			continue
		}

		// cover image
		ext := filepath.Ext(name)
		if isCoverExt(ext) {
			key := strings.TrimSuffix(name, ext)
			v := ensure(key)
			v.HasCover = true
		}
	}

	// ✅ WICHTIG: Model nur ausgeben, wenn wirklich ein Cover-Bild existiert
	for _, v := range byKey {
		if !v.HasCover {
			v.Model = ""
			v.GeneratedAt = ""
		}
		if strings.TrimSpace(v.Category) == "" {
			v.Category = ""
		}
	}

	// sortiert ausgeben (stabil)
	keys := make([]string, 0, len(byKey))
	for k := range byKey {
		keys = append(keys, k)
	}
	sort.Strings(keys)

	out := make([]coverInfoListItem, 0, len(keys))
	for _, k := range keys {
		out = append(out, *byKey[k])
	}

	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.Header().Set("Cache-Control", "no-store")

	if r.Method == http.MethodHead {
		w.WriteHeader(http.StatusOK)
		return
	}

	_ = json.NewEncoder(w).Encode(out)
}

func generatedCover(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet && r.Method != http.MethodHead {
		http.Error(w, "Nur GET/HEAD erlaubt", http.StatusMethodNotAllowed)
		return
	}

	category := r.URL.Query().Get("category")
	key, err := sanitizeCoverKey(category)
	if err != nil {
		http.Error(w, "category ungültig: "+err.Error(), http.StatusBadRequest)
		return
	}

	refresh := strings.ToLower(strings.TrimSpace(r.URL.Query().Get("refresh")))
	force := refresh == "1" || refresh == "true" || refresh == "yes"

	// Optional: model overlay
	modelQ := strings.TrimSpace(r.URL.Query().Get("model"))
	modelExplicit := modelQ != ""
	model := modelQ

	// Optional: src (Frontend kann ein konkretes Thumb vorgeben)
	src := strings.TrimSpace(r.URL.Query().Get("src"))

	fallbackModel := ""

	if ci, ok := readCoverInfoBestEffort(key); ok {
		if m := strings.TrimSpace(ci.Model); m != "" {
			fallbackModel = m
		}
	}

	// Wenn kein explizites model im Request: erstmal fallback übernehmen
	if model == "" {
		model = fallbackModel
	}

	// Wenn src gesetzt ist und model NICHT explizit: schon hier aus src ableiten (ok)
	if !modelExplicit && src != "" {
		if m := inferModelFromThumbLike(src); m != "" {
			model = m
		}
	}

	// kleine Request-ID (nur als Header/Debug; kein per-request log)
	reqID := strconv.FormatInt(time.Now().UnixNano(), 36)

	setDebugHeaders := func(cache string) {
		w.Header().Set("X-Cover-Key", key)
		w.Header().Set("X-Cover-Category", category)
		if model != "" {
			w.Header().Set("X-Cover-Model", model)
		}
		w.Header().Set("X-Cover-Cache", cache) // HIT | MISS | FORCED
		w.Header().Set("X-Request-Id", reqID)
	}

	// 1) Cache hit: direkt von Disk (nur wenn nicht force)
	if !force {
		// Wenn model im Request/abgeleitet da ist: info.json muss existieren & gleich sein, sonst neu erzeugen
		if model != "" {
			if ci, ok := readCoverInfoBestEffort(key); ok {
				if strings.TrimSpace(ci.Model) != model { // auch wenn ci.Model leer ist
					force = true
				}
			} else {
				// kein info.json -> force, damit wir model persistent bekommen
				force = true
			}
		}

		if !force {
			if p, fi, ok := findExistingCoverFile(key); ok {
				setDebugHeaders("HIT")

				// ✅ Cache-Hit: Cover existiert wirklich -> info.json best-effort updaten,
				// aber NUR wenn wir ein Model kennen (damit "kein Cover" auch kein Model zeigt)
				if model != "" {
					ci, ok := readCoverInfoBestEffort(key)
					if !ok {
						ci = coverInfo{Category: category}
					}

					ci.Category = category
					ci.Model = strings.TrimSpace(model)
					// Src NICHT überschreiben, wenn wir es bei HIT nicht kennen
					// ci.Src bleibt wie gehabt
					ci.GeneratedAt = time.Now().UTC().Format(time.RFC3339Nano)

					writeCoverInfoBestEffort(key, ci)
				}

				w.Header().Set("Cache-Control", "public, max-age=31536000")
				w.Header().Set("X-Content-Type-Options", "nosniff")

				ext := strings.ToLower(filepath.Ext(p))
				switch ext {
				case ".png":
					w.Header().Set("Content-Type", "image/png")
				case ".webp":
					w.Header().Set("Content-Type", "image/webp")
				case ".gif":
					w.Header().Set("Content-Type", "image/gif")
				default:
					w.Header().Set("Content-Type", "image/jpeg")
				}

				if r.Method == http.MethodHead {
					w.WriteHeader(http.StatusOK)
					return
				}

				f, err := os.Open(p)
				if err != nil {
					http.NotFound(w, r)
					return
				}
				defer f.Close()

				http.ServeContent(w, r, filepath.Base(p), fi.ModTime(), f)
				return
			}
		}
	}

	// Ab hier: entweder MISS oder FORCED => wir erzeugen (oder versuchen es)
	cacheStatus := "MISS"
	if force {
		cacheStatus = "FORCED"
	}
	setDebugHeaders(cacheStatus)

	// ✅ Globales Batch-Logging: nur beim echten Generate-Path
	coverBatchEnter(force)

	start := time.Now()
	status := http.StatusOK
	outcome := "ok"

	defer func() {
		w.Header().Set("X-Cover-Gen-Ms", strconv.FormatInt(time.Since(start).Milliseconds(), 10))
		coverBatchLeave(outcome, status)
	}()

	// 2) Kein Cache (oder force): Cover erzeugen und persistieren
	if _, err := ensureCoversDir(); err != nil {
		status = http.StatusInternalServerError
		outcome = "covers-dir"
		http.Error(w, "covers-dir nicht verfügbar: "+err.Error(), status)
		return
	}

	ctx, cancel := context.WithTimeout(r.Context(), 20*time.Second)
	defer cancel()

	var (
		raw      []byte
		mimeType string
		ext      string
	)

	thumbPath := "" // nur fürs Ableiten von model, wenn src leer ist

	usedSrc := "" // ✅ das speichern wir später in coverInfo

	// 2a) Wenn src gegeben: daraus bauen (lokal /generated/... oder http(s))
	if src != "" {
		var derr error
		raw, mimeType, derr = downloadBytes(ctx, src, r.Header.Get("User-Agent"))
		usedSrc = normalizeCoverSrc(src)
		if derr != nil {
			status = http.StatusBadRequest
			outcome = "src-download"
			http.Error(w, "src download failed: "+derr.Error(), status)
			return
		}
		ext, mimeType = detectImageExt(mimeType, raw)
		if len(raw) == 0 {
			status = http.StatusBadRequest
			outcome = "src-empty"
			http.Error(w, "src leer", status)
			return
		}

		// ✅ falls model immer noch leer ist, versuch JETZT aus src abzuleiten
		if model == "" {
			if m := inferModelFromThumbLike(src); m != "" {
				model = m
				// Header aktualisieren (weil model jetzt da ist)
				w.Header().Set("X-Cover-Model", model)
			}
		}

	} else {
		// 2b) Sonst: Backend wählt random Thumb passend zur Category
		var perr error
		thumbPath, perr = pickRandomThumbForCategory(ctx, category)
		if perr != nil {
			// Wenn es schon ein Cover gibt, lieber das liefern (auch wenn force)
			if p, fi, ok := findExistingCoverFile(key); ok {
				outcome = "fallback-existing-cover"
				status = http.StatusOK

				w.Header().Set("Cache-Control", "public, max-age=600")
				w.Header().Set("X-Content-Type-Options", "nosniff")

				ext2 := strings.ToLower(filepath.Ext(p))
				switch ext2 {
				case ".png":
					w.Header().Set("Content-Type", "image/png")
				case ".webp":
					w.Header().Set("Content-Type", "image/webp")
				case ".gif":
					w.Header().Set("Content-Type", "image/gif")
				default:
					w.Header().Set("Content-Type", "image/jpeg")
				}

				if r.Method == http.MethodHead {
					w.WriteHeader(http.StatusOK)
					return
				}

				f, err := os.Open(p)
				if err != nil {
					servePreviewStatusSVG(w, "No Cover", status)
					return
				}
				defer f.Close()

				http.ServeContent(w, r, filepath.Base(p), fi.ModTime(), f)
				return
			}

			outcome = "no-thumb"
			status = http.StatusNotFound
			if r.Method == http.MethodHead {
				w.WriteHeader(status)
				return
			}
			servePreviewStatusSVG(w, "No Cover", status)
			return

		}
		usedSrc = normalizeCoverSrc(thumbPath)

		raw, err = os.ReadFile(thumbPath)
		if err != nil || len(raw) == 0 {
			status = http.StatusInternalServerError
			outcome = "thumb-read"
			http.Error(w, "cover read fehlgeschlagen", status)
			return
		}

		// thumbs bei dir sind JPEG
		ext = ".jpg"
		mimeType = "image/jpeg"

		// ✅ falls model leer ist: aus thumbPath ableiten
		// thumbPath ist i.d.R. ".../generated/meta/<id>/thumbs.jpg"
		if model == "" {
			if m := inferModelFromThumbLike(thumbPath); m != "" {
				model = m
				w.Header().Set("X-Cover-Model", model)
			}
		}
	}

	// ✅ Final: wenn model nicht explizit gesetzt wurde, binde es an usedSrc
	if !modelExplicit {
		if m := inferModelFromThumbLike(usedSrc); m != "" {
			model = m
			w.Header().Set("X-Cover-Model", model)
		}
	}

	// ✅ 3) Overlay + Re-Encode
	img, _, derr := image.Decode(bytes.NewReader(raw))
	if derr == nil && img != nil {
		rgba := image.NewRGBA(img.Bounds())
		draw.Draw(rgba, rgba.Bounds(), img, img.Bounds().Min, draw.Src)

		var buf bytes.Buffer
		switch strings.ToLower(ext) {
		case ".png":
			_ = png.Encode(&buf, rgba)
			raw = buf.Bytes()
			ext = ".png"
			mimeType = "image/png"
		default:
			_ = jpeg.Encode(&buf, rgba, &jpeg.Options{Quality: 85})
			raw = buf.Bytes()
			ext = ".jpg"
			mimeType = "image/jpeg"
		}
	} else {
		outcome = "decode-failed-no-overlay"
	}

	// 4) Vorherige Cover-Dateien entfernen
	root, _ := coversRoot()
	for _, e := range []string{".jpg", ".png", ".webp", ".gif"} {
		_ = os.Remove(filepath.Join(root, key+e))
	}
	_ = os.Remove(filepath.Join(root, key+".info.json"))

	// 5) Persistieren
	dst, err := coverPathForCategory(key, ext)
	if err != nil {
		status = http.StatusInternalServerError
		outcome = "cover-path"
		http.Error(w, "cover path: "+err.Error(), status)
		return
	}
	if err := atomicWriteFile(dst, raw); err != nil {
		status = http.StatusInternalServerError
		outcome = "cover-write"
		http.Error(w, "cover write: "+err.Error(), status)
		return
	}

	// ✅ 6) info.json schreiben (best-effort)
	// model ist jetzt: Query-Param ODER aus info.json ODER aus src/thumbPath abgeleitet
	writeCoverInfoBestEffort(key, coverInfo{
		Category:    category,
		Model:       strings.TrimSpace(model),
		Src:         strings.TrimSpace(usedSrc),
		GeneratedAt: time.Now().UTC().Format(time.RFC3339Nano),
	})

	// 7) Ausliefern
	w.Header().Set("Cache-Control", "public, max-age=600")
	w.Header().Set("Content-Type", mimeType)
	w.Header().Set("X-Content-Type-Options", "nosniff")
	w.Header().Set("X-Cover-Bytes", strconv.Itoa(len(raw)))

	if r.Method == http.MethodHead {
		w.WriteHeader(http.StatusOK)
		return
	}

	w.WriteHeader(http.StatusOK)
	_, _ = w.Write(raw)
}

func sanitizeModelKey(k string) string {
	k = stripHotPrefix(strings.TrimSpace(k))
	if k == "" || k == "—" || strings.ContainsAny(k, `/\`) {
		return ""
	}
	return k
}

func modelKeyFromFilenameOrPath(file string, srcPath string, doneAbs string) string {
	// 1) bevorzugt aus Dateiname (OHNE Extension!)
	stem := strings.TrimSuffix(filepath.Base(strings.TrimSpace(file)), filepath.Ext(file))
	k := sanitizeModelKey(strings.TrimSpace(modelNameFromFilename(stem)))
	if k != "" {
		return k
	}

	// 2) Fallback: aus Quellpfad ableiten, wenn Datei in done/<model>/... lag
	if strings.TrimSpace(srcPath) != "" && strings.TrimSpace(doneAbs) != "" {
		srcDir := filepath.Clean(filepath.Dir(srcPath))
		doneAbs = filepath.Clean(doneAbs)

		// srcDir != doneAbs => wir sind in einem Unterordner, dessen Name i.d.R. das Model ist
		if !strings.EqualFold(srcDir, doneAbs) {
			k2 := sanitizeModelKey(filepath.Base(srcDir))
			if k2 != "" && !strings.EqualFold(k2, "keep") {
				return k2
			}
		}
	}

	return ""
}

func uniqueDestPath(dstDir, file string) (string, error) {
	dst := filepath.Join(dstDir, file)
	if _, err := os.Stat(dst); err == nil {
		ext := filepath.Ext(file)
		base := strings.TrimSuffix(file, ext)
		for i := 2; i <= 200; i++ {
			alt := fmt.Sprintf("%s__dup%d%s", base, i, ext)
			cand := filepath.Join(dstDir, alt)
			if _, err := os.Stat(cand); os.IsNotExist(err) {
				return cand, nil
			}
		}
		return "", fmt.Errorf("too many duplicates for %s", file)
	} else if err != nil && !os.IsNotExist(err) {
		return "", err
	}
	return dst, nil
}

func idFromVideoPath(videoPath string) string {
	name := filepath.Base(strings.TrimSpace(videoPath))
	return strings.TrimSuffix(name, filepath.Ext(name))
}

func assetIDForJob(job *RecordJob) string {
	if job == nil {
		return ""
	}

	// Prefer: Dateiname ohne Endung (und ohne HOT Prefix)
	out := strings.TrimSpace(job.Output)
	if out != "" {
		id := stripHotPrefix(idFromVideoPath(out))
		if strings.TrimSpace(id) != "" {
			return id
		}
	}

	// Fallback: JobID (sollte praktisch nie nötig sein)
	return strings.TrimSpace(job.ID)
}

func atomicWriteFile(dst string, data []byte) error {
	dir := filepath.Dir(dst)
	if err := os.MkdirAll(dir, 0o755); err != nil {
		return err
	}
	tmp, err := os.CreateTemp(dir, ".tmp-*")
	if err != nil {
		return err
	}
	tmpName := tmp.Name()
	_ = tmp.Chmod(0o644)

	_, werr := tmp.Write(data)
	cerr := tmp.Close()

	if werr != nil {
		_ = os.Remove(tmpName)
		return werr
	}
	if cerr != nil {
		_ = os.Remove(tmpName)
		return cerr
	}
	return os.Rename(tmpName, dst)
}

// Beim Start: loose Dateien in /done/keep (Root) in /done/keep/<model>/ einsortieren.
// Best-effort: wenn Model nicht ableitbar oder Ziel kollidiert, wird geskippt bzw. umbenannt.
func fixKeepRootFilesIntoModelSubdirs() {
	s := getSettings()

	doneAbs, err := resolvePathRelativeToApp(s.DoneDir)
	if err != nil || strings.TrimSpace(doneAbs) == "" {
		return
	}

	keepRoot := filepath.Join(doneAbs, "keep")

	ents, err := os.ReadDir(keepRoot)
	if err != nil {
		// keep existiert evtl. noch nicht -> nichts zu tun
		if os.IsNotExist(err) {
			return
		}
		fmt.Println("⚠️ keep scan failed:", err)
		return
	}

	moved := 0
	skipped := 0

	isVideo := func(name string) bool {
		low := strings.ToLower(name)
		if strings.Contains(low, ".part") || strings.Contains(low, ".tmp") {
			return false
		}
		ext := strings.ToLower(filepath.Ext(name))
		return ext == ".mp4" || ext == ".ts"
	}

	for _, e := range ents {
		if e.IsDir() {
			continue
		}

		name := e.Name()
		if !isVideo(name) {
			continue
		}

		// Quelle: /done/keep/<file>
		src := filepath.Join(keepRoot, name)

		// Model aus Dateiname ableiten (wie im keep-handler)
		stem := strings.TrimSuffix(name, filepath.Ext(name)) // ✅ ohne .mp4/.ts
		modelKey := sanitizeModelKey(strings.TrimSpace(modelNameFromFilename(stem)))

		// wenn nicht ableitbar -> skip
		if modelKey == "" || modelKey == "—" || strings.ContainsAny(modelKey, `/\`) {
			skipped++
			continue
		}

		dstDir := filepath.Join(keepRoot, modelKey)
		if err := os.MkdirAll(dstDir, 0o755); err != nil {
			fmt.Println("⚠️ keep mkdir failed:", err)
			skipped++
			continue
		}

		dst := filepath.Join(dstDir, name)

		// Wenn Ziel schon existiert -> unique Name finden
		if _, err := os.Stat(dst); err == nil {
			ext := filepath.Ext(name)
			base := strings.TrimSuffix(name, ext)

			found := false
			for i := 2; i <= 200; i++ {
				alt := fmt.Sprintf("%s__dup%d%s", base, i, ext)
				cand := filepath.Join(dstDir, alt)
				if _, err := os.Stat(cand); os.IsNotExist(err) {
					dst = cand
					found = true
					break
				}
			}
			if !found {
				fmt.Println("⚠️ keep fix: too many duplicates, skip:", name)
				skipped++
				continue
			}
		} else if err != nil && !os.IsNotExist(err) {
			fmt.Println("⚠️ keep stat dst failed:", err)
			skipped++
			continue
		}

		// Verschieben (Windows-lock robust)
		if err := renameWithRetry(src, dst); err != nil {
			fmt.Println("⚠️ keep fix rename failed:", err)
			skipped++
			continue
		}

		moved++
	}

	if moved > 0 || skipped > 0 {
		fmt.Printf("🧹 keep fix: moved=%d skipped=%d (root=%s)\n", moved, skipped, keepRoot)
	}
}

func findFinishedFileByID(id string) (string, error) {
	s := getSettings()
	recordAbs, _ := resolvePathRelativeToApp(s.RecordDir)
	doneAbs, _ := resolvePathRelativeToApp(s.DoneDir)

	base := stripHotPrefix(strings.TrimSpace(id))
	if base == "" {
		return "", fmt.Errorf("not found")
	}

	names := []string{
		base + ".mp4",
		"HOT " + base + ".mp4",
		base + ".ts",
		"HOT " + base + ".ts",
	}

	// done (root + /done/<subdir>/) + keep (root + /done/keep/<subdir>/)
	for _, name := range names {
		if p, _, ok := findFileInDirOrOneLevelSubdirs(doneAbs, name, "keep"); ok {
			return p, nil
		}
		if p, _, ok := findFileInDirOrOneLevelSubdirs(filepath.Join(doneAbs, "keep"), name, ""); ok {
			return p, nil
		}
		if p, _, ok := findFileInDirOrOneLevelSubdirs(recordAbs, name, ""); ok {
			return p, nil
		}
	}

	return "", fmt.Errorf("not found")
}

func servePreviewThumbAlias(w http.ResponseWriter, r *http.Request, id, file string) {
	// 1) Wenn Job bekannt (id = job.ID): assetID aus Output ableiten
	jobsMu.Lock()
	job := jobs[id]
	jobsMu.Unlock()

	if job != nil {
		assetID := assetIDForJob(job)
		if assetID != "" {
			if thumbPath, err := generatedThumbFile(assetID); err == nil {
				if st, err := os.Stat(thumbPath); err == nil && !st.IsDir() && st.Size() > 0 {
					// running => no-store, finished => cache ok (du willst live eher no-store)
					if job.Status == JobRunning {
						serveLivePreviewJPEGFile(w, r, thumbPath)
					} else {
						servePreviewJPEGFile(w, r, thumbPath)
					}
					return
				}
			}
		}

		// Optional: wenn du bei running noch in-memory fallback willst:
		if job.Status == JobRunning {
			job.previewMu.Lock()
			cached := job.previewJpeg
			job.previewMu.Unlock()
			if len(cached) > 0 {
				serveLivePreviewJPEGBytes(w, cached)
				return
			}
		}

		// Placeholder statt hartem 404
		servePreviewStatusSVG(w, "Preview", http.StatusOK)
		return
	}

	// 2) Kein Job im RAM: id als assetID behandeln (finished files nach Neustart)
	// "preview.jpg" als Alias auf thumbs.jpg
	assetID := stripHotPrefix(strings.TrimSpace(id))
	if assetID == "" {
		http.NotFound(w, r)
		return
	}

	if thumbPath, err := generatedThumbFile(assetID); err == nil {
		if st, err := os.Stat(thumbPath); err == nil && !st.IsDir() && st.Size() > 0 {
			servePreviewJPEGFile(w, r, thumbPath)
			return
		}
	}

	http.NotFound(w, r)
}

func isHover(r *http.Request) bool {
	v := strings.ToLower(strings.TrimSpace(r.URL.Query().Get("hover")))
	return v == "1" || v == "true" || v == "yes"
}

func touchPreview(job *RecordJob) {
	if job == nil {
		return
	}
	jobsMu.Lock()
	job.previewLastHit = time.Now()
	jobsMu.Unlock()
}

func ensurePreviewStarted(r *http.Request, job *RecordJob) {
	if job == nil {
		return
	}
	job.previewStartMu.Lock()
	defer job.previewStartMu.Unlock()

	jobsMu.Lock()
	// läuft schon?
	if job.previewCmd != nil && job.PreviewDir != "" {
		job.previewLastHit = time.Now()
		jobsMu.Unlock()
		return
	}

	// brauchen M3U8 URL
	m3u8 := strings.TrimSpace(job.PreviewM3U8)
	cookie := strings.TrimSpace(job.PreviewCookie)
	ua := strings.TrimSpace(job.PreviewUA)
	jobsMu.Unlock()

	if m3u8 == "" {
		return
	}

	// eigener Context für Preview (WICHTIG: nicht der Recording ctx)
	pctx, cancel := context.WithCancel(context.Background())

	// PreviewDir temp
	assetID := assetIDForJob(job)
	pdir := filepath.Join(os.TempDir(), "rec_preview", assetID)

	jobsMu.Lock()
	job.PreviewDir = pdir
	job.previewCancel = cancel
	job.previewLastHit = time.Now()
	jobsMu.Unlock()

	_ = startPreviewHLS(pctx, job, m3u8, pdir, cookie, ua)
}

func recordPreview(w http.ResponseWriter, r *http.Request) {
	// optional aber sinnvoll: nur GET/HEAD erlauben
	if r.Method != http.MethodGet && r.Method != http.MethodHead {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}

	id := strings.TrimSpace(r.URL.Query().Get("id"))
	if id == "" {
		// ✅ Alias: Frontend schickt "name"
		id = strings.TrimSpace(r.URL.Query().Get("name"))
	}
	if id == "" {
		http.Error(w, "id fehlt", http.StatusBadRequest)
		return
	}

	// ✅ NEW: JPEG requests abfangen
	if file := strings.TrimSpace(r.URL.Query().Get("file")); file != "" {
		if file == "thumbs.jpg" || file == "preview.jpg" {
			servePreviewThumbAlias(w, r, id, file)
			return
		}
		// HLS wie gehabt
		servePreviewHLSFile(w, r, id, file)
		return
	}

	// Schauen, ob wir einen Job mit dieser ID kennen (laufend oder gerade fertig)
	jobsMu.Lock()
	job, ok := jobs[id]
	jobsMu.Unlock()

	if ok {
		// ✅ 0) Running: wenn generated/<jobId>/thumbs.jpg existiert -> sofort ausliefern
		// (kein ffmpeg pro HTTP-Request)
		if job.Status == "running" {
			assetID := assetIDForJob(job)
			if assetID != "" {
				if thumbPath, err := generatedThumbFile(assetID); err == nil {
					if st, err := os.Stat(thumbPath); err == nil && !st.IsDir() && st.Size() > 0 {
						serveLivePreviewJPEGFile(w, r, thumbPath)
						return
					}
				}
			}
		}

		// ✅ Fallback: alter In-Memory-Cache (falls thumbs.jpg noch nicht da ist)
		job.previewMu.Lock()
		cached := job.previewJpeg
		cachedAt := job.previewJpegAt
		freshWindow := 8 * time.Second
		fresh := len(cached) > 0 && !cachedAt.IsZero() && time.Since(cachedAt) < freshWindow

		// Wenn nicht frisch, ggf. im Hintergrund aktualisieren (einmal gleichzeitig)
		if !fresh && !job.previewGen {
			job.previewGen = true
			go func(j *RecordJob, jobID string) {
				defer func() {
					j.previewMu.Lock()
					j.previewGen = false
					j.previewMu.Unlock()
				}()

				var img []byte
				var genErr error

				// 1) aus Preview-Segmenten
				previewDir := strings.TrimSpace(j.PreviewDir)
				if previewDir != "" {
					img, genErr = extractLastFrameFromPreviewDir(previewDir)
				}

				// 2) Fallback: aus der Ausgabedatei
				if genErr != nil || len(img) == 0 {
					outPath := strings.TrimSpace(j.Output)
					if outPath != "" {
						outPath = filepath.Clean(outPath)
						if !filepath.IsAbs(outPath) {
							if abs, err := resolvePathRelativeToApp(outPath); err == nil {
								outPath = abs
							}
						}
						if fi, err := os.Stat(outPath); err == nil && !fi.IsDir() && fi.Size() > 0 {
							img, genErr = extractLastFrameJPEG(outPath)
							if genErr != nil {
								img, _ = extractFirstFrameJPEG(outPath)
							}
						}
					}
				}

				if len(img) > 0 {
					j.previewMu.Lock()
					j.previewJpeg = img
					j.previewJpegAt = time.Now()
					j.previewMu.Unlock()
				}
			}(job, id)
		}

		// Wir liefern entweder ein frisches Bild, oder das zuletzt gecachte.
		out := cached
		job.previewMu.Unlock()
		if len(out) > 0 {
			serveLivePreviewJPEGBytes(w, out) // ✅ no-store für laufende Jobs
			return
		}

		// ✅ Wenn Preview definitiv nicht geht -> Placeholder statt 204
		jobsMu.Lock()
		state := strings.TrimSpace(job.PreviewState)
		jobsMu.Unlock()

		if state == "private" {
			servePreviewStatusSVG(w, "Private", http.StatusOK)
			return
		}
		if state == "offline" {
			servePreviewStatusSVG(w, "Offline", http.StatusOK)
			return
		}

		// noch kein Bild verfügbar -> 204 (Frontend zeigt Placeholder und retry)
		w.Header().Set("Cache-Control", "no-store")
		w.WriteHeader(http.StatusNoContent)
		return
	}

	// 3️⃣ Kein Job im RAM → id als Dateistamm für fertige Downloads behandeln
	servePreviewForFinishedFile(w, r, id)
}

func serveLivePreviewJPEGFile(w http.ResponseWriter, r *http.Request, path string) {
	f, err := os.Open(path)
	if err != nil {
		http.NotFound(w, r)
		return
	}
	defer f.Close()

	st, err := f.Stat()
	if err != nil || st.IsDir() || st.Size() == 0 {
		http.NotFound(w, r)
		return
	}

	w.Header().Set("Content-Type", "image/jpeg")
	w.Header().Set("Cache-Control", "no-store")
	http.ServeContent(w, r, "thumbs.jpg", st.ModTime(), f)
}

func updateLiveThumbOnce(ctx context.Context, job *RecordJob) {
	// Snapshot unter Lock holen
	jobsMu.Lock()
	status := job.Status
	previewDir := job.PreviewDir
	out := job.Output
	jobsMu.Unlock()

	if status != "running" {
		return
	}

	// Zielpfad: generated/<jobId>/thumbs.jpg
	assetID := assetIDForJob(job)
	thumbPath, err := generatedThumbFile(assetID)

	if err != nil {
		return
	}

	// Wenn frisch genug: skip
	if st, err := os.Stat(thumbPath); err == nil && st.Size() > 0 {
		if time.Since(st.ModTime()) < 10*time.Second {
			return
		}
	}

	// Concurrency limit über thumbSem
	if thumbSem != nil {
		thumbCtx, cancel := context.WithTimeout(ctx, 3*time.Second)
		defer cancel()

		if err := thumbSem.Acquire(thumbCtx); err != nil {
			return
		}
		defer thumbSem.Release()
	}

	var img []byte

	// 1) bevorzugt aus Preview-Segmenten
	if previewDir != "" {
		if b, err := extractLastFrameFromPreviewDirThumb(previewDir); err == nil && len(b) > 0 {
			img = b
		}
	}

	// 2) fallback aus Output-Datei (kann bei partial files manchmal langsamer sein)
	if len(img) == 0 && out != "" {
		if b, err := extractLastFrameJPEGScaled(out, 320, 14); err == nil && len(b) > 0 {
			img = b
		}
	}

	if len(img) == 0 {
		return
	}

	_ = atomicWriteFile(thumbPath, img)
}

func startLiveThumbLoop(ctx context.Context, job *RecordJob) {
	// einmalig starten
	jobsMu.Lock()
	if job.LiveThumbStarted {
		jobsMu.Unlock()
		return
	}
	job.LiveThumbStarted = true
	jobsMu.Unlock()

	go func() {
		// sofort einmal versuchen
		updateLiveThumbOnce(ctx, job)

		for {
			// dynamische Frequenz: je mehr aktive Jobs, desto langsamer (weniger Last)
			jobsMu.Lock()
			nRunning := 0
			for _, j := range jobs {
				if j != nil && j.Status == "running" {
					nRunning++
				}
			}
			jobsMu.Unlock()

			delay := 12 * time.Second
			if nRunning >= 6 {
				delay = 18 * time.Second
			}
			if nRunning >= 12 {
				delay = 25 * time.Second
			}

			select {
			case <-ctx.Done():
				return
			case <-time.After(delay):
				// ✅ Stoppen, sobald Job nicht mehr läuft
				jobsMu.Lock()
				st := job.Status
				jobsMu.Unlock()
				if st != "running" {
					return
				}

				updateLiveThumbOnce(ctx, job)
			}
		}
	}()
}

// Fallback: Preview für fertige Dateien nur anhand des Dateistamms (id)
func servePreviewForFinishedFile(w http.ResponseWriter, r *http.Request, id string) {
	var err error
	id, err = sanitizeID(id)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	outPath, err := findFinishedFileByID(id)
	if err != nil {
		http.Error(w, "preview nicht verfügbar", http.StatusNotFound)
		return
	}

	if err := ensureGeneratedDirs(); err != nil {
		http.Error(w, "generated-dir nicht verfügbar: "+err.Error(), http.StatusInternalServerError)
		return
	}

	// ✅ Assets immer auf "basename ohne HOT" ablegen
	assetID := stripHotPrefix(id)
	if assetID == "" {
		assetID = id
	}

	assetDir, err := ensureGeneratedDir(assetID)
	if err != nil {
		http.Error(w, "generated-dir nicht verfügbar: "+err.Error(), http.StatusInternalServerError)
		return
	}

	// ✅ Frame-Caching für t=... (optional)
	if tStr := strings.TrimSpace(r.URL.Query().Get("t")); tStr != "" {
		if sec, err := strconv.ParseFloat(tStr, 64); err == nil && sec >= 0 {
			secI := int64(sec + 0.5)
			if secI < 0 {
				secI = 0
			}
			framePath := filepath.Join(assetDir, fmt.Sprintf("t_%d.jpg", secI))
			if fi, err := os.Stat(framePath); err == nil && !fi.IsDir() && fi.Size() > 0 {
				servePreviewJPEGFile(w, r, framePath)
				return
			}

			img, err := extractFrameAtTimeJPEG(outPath, float64(secI))
			if err == nil && len(img) > 0 {
				_ = atomicWriteFile(framePath, img)
				servePreviewJPEGBytes(w, img)
				return
			}
		}
	}

	thumbPath := filepath.Join(assetDir, "thumbs.jpg")

	// 1) Cache hit (neu)
	if fi, err := os.Stat(thumbPath); err == nil && !fi.IsDir() && fi.Size() > 0 {
		servePreviewJPEGFile(w, r, thumbPath)
		return
	}

	// 2) Legacy-Migration (best effort)
	if thumbsLegacy, _ := generatedThumbsRoot(); strings.TrimSpace(thumbsLegacy) != "" {
		candidates := []string{
			filepath.Join(thumbsLegacy, assetID, "preview.jpg"),
			filepath.Join(thumbsLegacy, id, "preview.jpg"),
			filepath.Join(thumbsLegacy, assetID+".jpg"),
			filepath.Join(thumbsLegacy, id+".jpg"),
		}
		for _, c := range candidates {
			if fi, err := os.Stat(c); err == nil && !fi.IsDir() && fi.Size() > 0 {
				if b, rerr := os.ReadFile(c); rerr == nil && len(b) > 0 {
					_ = atomicWriteFile(thumbPath, b)
					servePreviewJPEGBytes(w, b)
					return
				}
			}
		}
	}

	// 3) Neu erzeugen
	genCtx, cancel := context.WithTimeout(r.Context(), 30*time.Second)
	defer cancel()

	var t float64 = 0
	if dur, derr := durationSecondsCached(genCtx, outPath); derr == nil && dur > 0 {
		t = dur * 0.5
	}

	img, err := extractFrameAtTimeJPEG(outPath, t)
	if err != nil || len(img) == 0 {
		img, err = extractLastFrameJPEG(outPath)
		if err != nil || len(img) == 0 {
			img, err = extractFirstFrameJPEG(outPath)
			if err != nil || len(img) == 0 {
				http.Error(w, "konnte preview nicht erzeugen", http.StatusInternalServerError)
				return
			}
		}
	}

	_ = atomicWriteFile(thumbPath, img)
	servePreviewJPEGBytes(w, img)
}

const maxInt64 = int64(^uint64(0) >> 1)

func removeJobsByOutputBasename(file string) {
	file = strings.TrimSpace(file)
	if file == "" {
		return
	}

	removed := false
	jobsMu.Lock()
	for id, j := range jobs {
		if j == nil {
			continue
		}
		out := strings.TrimSpace(j.Output)
		if out == "" {
			continue
		}
		if filepath.Base(out) == file {
			delete(jobs, id)
			removed = true
		}
	}
	jobsMu.Unlock()

	if removed {
		notifyJobsChanged()
	}
}

func renameJobsOutputBasename(oldFile, newFile string) {
	oldFile = strings.TrimSpace(oldFile)
	newFile = strings.TrimSpace(newFile)
	if oldFile == "" || newFile == "" {
		return
	}

	changed := false
	jobsMu.Lock()
	for _, j := range jobs {
		if j == nil {
			continue
		}
		out := strings.TrimSpace(j.Output)
		if out == "" {
			continue
		}
		if filepath.Base(out) == oldFile {
			j.Output = filepath.Join(filepath.Dir(out), newFile)
			changed = true
		}
	}
	jobsMu.Unlock()

	if changed {
		notifyJobsChanged()
	}
}

// nimmt jetzt *HTTPClient entgegen
func FetchPlaylist(ctx context.Context, hc *HTTPClient, hlsSource, httpCookie string) (*Playlist, error) {
	if hlsSource == "" {
		return nil, errors.New("HLS-URL leer")
	}

	req, err := hc.NewRequest(ctx, http.MethodGet, hlsSource, httpCookie)
	if err != nil {
		return nil, fmt.Errorf("Fehler beim Erstellen der Playlist-Request: %w", err)
	}

	resp, err := hc.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("Fehler beim Laden der Playlist: %w", err)
	}
	defer resp.Body.Close()

	playlist, listType, err := m3u8.DecodeFrom(resp.Body, true)
	if err != nil || listType != m3u8.MASTER {
		return nil, errors.New("keine gültige Master-Playlist")
	}

	master := playlist.(*m3u8.MasterPlaylist)
	var bestURI string
	var bestWidth int
	var bestFramerate int

	for _, variant := range master.Variants {
		if variant == nil || variant.Resolution == "" {
			continue
		}

		parts := strings.Split(variant.Resolution, "x")
		if len(parts) != 2 {
			continue
		}

		width, err := strconv.Atoi(parts[0])
		if err != nil {
			continue
		}

		fr := 30
		if strings.Contains(variant.Name, "FPS:60.0") {
			fr = 60
		}

		if width > bestWidth || (width == bestWidth && fr > bestFramerate) {
			bestWidth = width
			bestFramerate = fr
			bestURI = variant.URI
		}
	}

	if bestURI == "" {
		return nil, errors.New("keine gültige Auflösung gefunden")
	}

	root := hlsSource[:strings.LastIndex(hlsSource, "/")+1]
	return &Playlist{
		PlaylistURL: root + bestURI,
		RootURL:     root,
		Resolution:  bestWidth,
		Framerate:   bestFramerate,
	}, nil
}

func readLine() string {
	r := bufio.NewReader(os.Stdin)
	s, _ := r.ReadString('\n')
	return strings.TrimRight(s, "\r\n")
}

func fileExists(path string) bool {
	_, err := os.Stat(path)
	return err == nil
}