// backend\rating.go

package main

import (
	"math"
	"sort"
	"strings"
)

type aiRatingMeta struct {
	Score                  float64 `json:"score"`
	Stars                  int     `json:"stars"`
	Segments               int     `json:"segments"`
	SegmentsPerMinute      float64 `json:"segmentsPerMinute"`
	FlaggedSeconds         float64 `json:"flaggedSeconds"`
	WeightedFlaggedSeconds float64 `json:"weightedFlaggedSeconds"`
	CoverageRatio          float64 `json:"coverageRatio"`
	WeightedCoverageRatio  float64 `json:"weightedCoverageRatio"`
	LongestSegmentSeconds  float64 `json:"longestSegmentSeconds"`
	AvgConfidence          float64 `json:"avgConfidence"`
}

const (
	// Normales Zusammenziehen sehr kurzer Pausen.
	ratingMaxSilentGapSec = 4.5

	// Größere Lücken dürfen überbrückt werden,
	// wenn beide Seiten stark genug / thematisch ähnlich sind.
	ratingBridgeStrongGapSec = 12.0

	ratingMinSegmentDurationSec = 2.5
)

func ratingClamp01(v float64) float64 {
	if v < 0 {
		return 0
	}
	if v > 1 {
		return 1
	}
	return v
}

func ratingRound(v float64, places int) float64 {
	p := math.Pow(10, float64(places))
	return math.Round(v*p) / p
}

func ratingSmoothStep(v float64) float64 {
	v = ratingClamp01(v)
	return v * v * (3 - 2*v)
}

func ratingSoftCap(value, knee float64) float64 {
	if value <= 0 || knee <= 0 {
		return 0
	}
	return value / (value + knee)
}

func ratingEffectiveDurationSeconds(seconds float64) float64 {
	if seconds <= 0 {
		return 0
	}

	// Lange Segmente zählen, aber nicht linear unendlich stark.
	const kneeSeconds = 26.0
	return kneeSeconds * math.Log1p(seconds/kneeSeconds)
}

func normalizeSegmentLabel(label string) string {
	label = strings.ToLower(strings.TrimSpace(label))

	label = strings.TrimPrefix(label, "detector:")
	label = strings.TrimPrefix(label, "body:")
	label = strings.TrimPrefix(label, "object:")
	label = strings.TrimPrefix(label, "clothing:")
	label = strings.TrimPrefix(label, "position:")
	label = strings.TrimPrefix(label, "person:")

	return strings.TrimSpace(label)
}

func isPersonSegmentLabel(label string) bool {
	label = strings.ToLower(strings.TrimSpace(label))

	label = strings.TrimPrefix(label, "detector:")
	label = strings.TrimPrefix(label, "body:")
	label = strings.TrimPrefix(label, "object:")
	label = strings.TrimPrefix(label, "clothing:")
	label = strings.TrimPrefix(label, "position:")
	label = strings.TrimPrefix(label, "person:")

	switch label {
	case "person",
		"person_unknown",
		"person_male",
		"person_female",
		"male_person",
		"female_person",
		"people_male",
		"people_female":
		return true
	default:
		return false
	}
}

func isKnownPositionLabel(label string) bool {
	label = strings.ToLower(strings.TrimSpace(label))

	switch label {
	case "unknown",
		"missionary",
		"doggy",
		"doggystyle",
		"cowgirl",
		"reverse_cowgirl",
		"cunnilingus",
		"prone_bone",
		"standing",
		"standing_doggy",
		"spooning",
		"facesitting",
		"handjob",
		"blowjob",
		"toy_play",
		"fingering",
		"69":
		return true
	default:
		return false
	}
}

func positionSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))

	switch label {
	case "doggy", "doggystyle", "standing_doggy":
		return 1.00
	case "cowgirl", "reverse_cowgirl":
		return 0.98
	case "missionary", "prone_bone":
		return 0.95
	case "blowjob", "cunnilingus", "69", "facesitting":
		return 0.94
	case "toy_play":
		return 0.88
	case "handjob", "fingering":
		return 0.84
	case "spooning":
		return 0.78
	case "standing":
		return 0.42
	default:
		return 0.00
	}
}

func bodyPartSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))

	switch label {
	case "pussy", "vulva":
		return 1.00
	case "penis":
		return 0.95
	case "anus":
		return 0.90
	case "breasts":
		return 0.80
	case "ass", "buttocks":
		return 0.66
	case "tongue":
		return 0.46
	default:
		return 0.00
	}
}

func objectSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))

	switch label {
	case "dildo", "vibrator", "strapon", "buttplug":
		return 0.86
	case "handcuffs", "blindfold", "collar":
		return 0.58
	case "shower":
		return 0.42
	case "towel":
		return 0.28
	default:
		return 0.00
	}
}

func clothingSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))

	switch label {
	case "lingerie":
		return 0.64
	case "panties", "bra":
		return 0.58
	case "bikini":
		return 0.42
	case "stockings", "heels":
		return 0.40
	case "skirt", "dress", "hotpants", "croptop":
		return 0.34
	default:
		return 0.00
	}
}

func personContextWeight(label string) float64 {
	if !isPersonSegmentLabel(label) {
		return 0
	}

	// Personen sind Kontext, aber nie alleiniger Rating-Treiber.
	return 0.18
}

func detectorSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))

	if isPersonSegmentLabel(label) {
		return personContextWeight(label)
	}

	if w := bodyPartSeverityWeight(label); w > 0 {
		return w
	}
	if w := objectSeverityWeight(label); w > 0 {
		return w
	}
	if w := clothingSeverityWeight(label); w > 0 {
		return w
	}
	if isKnownPositionLabel(label) {
		return positionSeverityWeight(label)
	}

	return 0.00
}

type ratingSignalSet struct {
	Position float64
	Body     float64
	Object   float64
	Clothing float64
	Person   float64

	HasPosition bool
	HasBody     bool
	HasObject   bool
	HasClothing bool
	HasPerson   bool
}

func normalizeRatingSignalLabel(label string) string {
	label = strings.ToLower(strings.TrimSpace(label))
	if label == "" || label == "unknown" {
		return ""
	}

	if strings.HasPrefix(label, "combo:") {
		return label
	}

	if strings.HasPrefix(label, "detector:") {
		return normalizeRatingSignalLabel(strings.TrimPrefix(label, "detector:"))
	}

	if strings.HasPrefix(label, "position:") {
		raw := strings.TrimPrefix(label, "position:")
		if isKnownPositionLabel(raw) && positionSeverityWeight(raw) > 0 {
			return "position:" + raw
		}
		return ""
	}

	if strings.HasPrefix(label, "body:") {
		raw := strings.TrimPrefix(label, "body:")
		if bodyPartSeverityWeight(raw) > 0 {
			return "body:" + raw
		}
		return ""
	}

	if strings.HasPrefix(label, "object:") {
		raw := strings.TrimPrefix(label, "object:")
		if objectSeverityWeight(raw) > 0 {
			return "object:" + raw
		}
		return ""
	}

	if strings.HasPrefix(label, "clothing:") {
		raw := strings.TrimPrefix(label, "clothing:")
		if clothingSeverityWeight(raw) > 0 {
			return "clothing:" + raw
		}
		return ""
	}

	if strings.HasPrefix(label, "person:") {
		raw := strings.TrimPrefix(label, "person:")
		if isPersonSegmentLabel(raw) {
			return "person:" + normalizeSegmentLabel(raw)
		}
		return ""
	}

	raw := normalizeSegmentLabel(label)
	if raw == "" || raw == "unknown" {
		return ""
	}

	if isPersonSegmentLabel(raw) {
		return "person:" + raw
	}
	if isKnownPositionLabel(raw) && positionSeverityWeight(raw) > 0 {
		return "position:" + raw
	}
	if bodyPartSeverityWeight(raw) > 0 {
		return "body:" + raw
	}
	if objectSeverityWeight(raw) > 0 {
		return "object:" + raw
	}
	if clothingSeverityWeight(raw) > 0 {
		return "clothing:" + raw
	}

	return ""
}

func ratingSignalSetAddLabel(set *ratingSignalSet, label string) {
	label = normalizeRatingSignalLabel(label)
	if label == "" {
		return
	}

	switch {
	case strings.HasPrefix(label, "position:"):
		raw := strings.TrimPrefix(label, "position:")
		w := positionSeverityWeight(raw)
		if w > set.Position {
			set.Position = w
		}
		if w > 0 {
			set.HasPosition = true
		}

	case strings.HasPrefix(label, "body:"):
		raw := strings.TrimPrefix(label, "body:")
		w := bodyPartSeverityWeight(raw)
		if w > set.Body {
			set.Body = w
		}
		if w > 0 {
			set.HasBody = true
		}

	case strings.HasPrefix(label, "object:"):
		raw := strings.TrimPrefix(label, "object:")
		w := objectSeverityWeight(raw)
		if w > set.Object {
			set.Object = w
		}
		if w > 0 {
			set.HasObject = true
		}

	case strings.HasPrefix(label, "clothing:"):
		raw := strings.TrimPrefix(label, "clothing:")
		w := clothingSeverityWeight(raw)
		if w > set.Clothing {
			set.Clothing = w
		}
		if w > 0 {
			set.HasClothing = true
		}

	case strings.HasPrefix(label, "person:"):
		raw := strings.TrimPrefix(label, "person:")
		w := personContextWeight(raw)
		if w > set.Person {
			set.Person = w
		}
		if w > 0 {
			set.HasPerson = true
		}
	}
}

func ratingSignalSetFromLabel(label string) ratingSignalSet {
	label = strings.ToLower(strings.TrimSpace(label))

	var set ratingSignalSet

	if strings.HasPrefix(label, "combo:") {
		raw := strings.TrimPrefix(label, "combo:")
		for _, part := range strings.Split(raw, "+") {
			ratingSignalSetAddLabel(&set, part)
		}
		return set
	}

	ratingSignalSetAddLabel(&set, label)
	return set
}

func ratingSignalSetHasInterestingContent(set ratingSignalSet) bool {
	return set.HasPosition || set.HasBody || set.HasObject || set.HasClothing
}

func contextualSegmentSeverityWeight(label string) float64 {
	set := ratingSignalSetFromLabel(label)

	if !ratingSignalSetHasInterestingContent(set) {
		return 0
	}

	var score float64

	if set.HasPosition {
		score =
			0.66*set.Position +
				0.17*set.Body +
				0.10*set.Object +
				0.05*set.Clothing +
				0.02*set.Person

		if set.HasBody {
			score += 0.055
		}
		if set.HasObject {
			score += 0.040
		}
		if set.HasClothing {
			score += 0.020
		}
		if set.HasPerson {
			score += 0.015
		}

		// Standing/Sitting ohne Kontext bleibt schwach.
		if set.Position < 0.60 && !set.HasBody && !set.HasObject && !set.HasClothing {
			score = math.Min(score, 0.42)
		}

		return ratingClamp01(score)
	}

	score =
		0.54*set.Body +
			0.30*set.Object +
			0.14*set.Clothing +
			0.02*set.Person

	if set.HasBody && set.HasObject {
		score += 0.09
	}
	if set.HasBody && set.HasClothing {
		score += 0.04
	}
	if set.HasObject && set.HasClothing {
		score += 0.03
	}
	if set.HasPerson && (set.HasBody || set.HasObject || set.HasClothing) {
		score += 0.015
	}

	// Kleidung alleine soll interessant sein können, aber nicht stark.
	if set.HasClothing && !set.HasBody && !set.HasObject {
		score = math.Min(score, 0.38)
	}

	// Ohne Position nicht zu aggressiv.
	score = math.Min(score, 0.72)

	return ratingClamp01(score)
}

func comboSegmentSeverityWeight(label string) float64 {
	set := ratingSignalSetFromLabel(label)
	return contextualSegmentSeverityWeightFromSet(set)
}

func contextualSegmentSeverityWeightFromSet(set ratingSignalSet) float64 {
	if !ratingSignalSetHasInterestingContent(set) {
		return 0
	}

	var labelParts []string

	if set.HasPosition {
		labelParts = append(labelParts, "position:x")
	}
	if set.HasBody {
		labelParts = append(labelParts, "body:x")
	}
	if set.HasObject {
		labelParts = append(labelParts, "object:x")
	}
	if set.HasClothing {
		labelParts = append(labelParts, "clothing:x")
	}
	if set.HasPerson {
		labelParts = append(labelParts, "person:x")
	}

	_ = labelParts

	var score float64

	if set.HasPosition {
		score =
			0.66*set.Position +
				0.17*set.Body +
				0.10*set.Object +
				0.05*set.Clothing +
				0.02*set.Person

		if set.HasBody {
			score += 0.055
		}
		if set.HasObject {
			score += 0.040
		}
		if set.HasClothing {
			score += 0.020
		}
		if set.HasPerson {
			score += 0.015
		}

		if set.Position < 0.60 && !set.HasBody && !set.HasObject && !set.HasClothing {
			score = math.Min(score, 0.42)
		}

		return ratingClamp01(score)
	}

	score =
		0.54*set.Body +
			0.30*set.Object +
			0.14*set.Clothing +
			0.02*set.Person

	if set.HasBody && set.HasObject {
		score += 0.09
	}
	if set.HasBody && set.HasClothing {
		score += 0.04
	}
	if set.HasObject && set.HasClothing {
		score += 0.03
	}
	if set.HasPerson && (set.HasBody || set.HasObject || set.HasClothing) {
		score += 0.015
	}

	if set.HasClothing && !set.HasBody && !set.HasObject {
		score = math.Min(score, 0.38)
	}

	score = math.Min(score, 0.72)

	return ratingClamp01(score)
}

func segmentSeverityWeight(label string) float64 {
	label = strings.ToLower(strings.TrimSpace(label))
	if label == "" {
		return 0
	}

	if strings.HasPrefix(label, "combo:") {
		return comboSegmentSeverityWeight(label)
	}

	normalized := normalizeRatingSignalLabel(label)
	if normalized == "" {
		return 0
	}

	set := ratingSignalSetFromLabel(normalized)
	sev := contextualSegmentSeverityWeightFromSet(set)
	if sev > 0 {
		return sev
	}

	raw := normalizeSegmentLabel(normalized)
	if raw == "" {
		return 0
	}

	return detectorSeverityWeight(raw)
}

func ratingSegmentSeverity(label string) float64 {
	return segmentSeverityWeight(label)
}

func ratingSignalPriority(label string) int {
	label = normalizeRatingSignalLabel(label)

	switch {
	case strings.HasPrefix(label, "position:"):
		return 100
	case strings.HasPrefix(label, "body:"):
		return 80
	case strings.HasPrefix(label, "object:"):
		return 60
	case strings.HasPrefix(label, "clothing:"):
		return 40
	case strings.HasPrefix(label, "person:"):
		return 20
	default:
		return 0
	}
}

func buildRatingComboLabel(labels map[string]bool) string {
	if len(labels) == 0 {
		return ""
	}

	parts := make([]string, 0, len(labels))
	set := ratingSignalSet{}

	for label := range labels {
		normalized := normalizeRatingSignalLabel(label)
		if normalized == "" {
			continue
		}

		ratingSignalSetAddLabel(&set, normalized)
		parts = append(parts, normalized)
	}

	if !ratingSignalSetHasInterestingContent(set) {
		return ""
	}

	sort.SliceStable(parts, func(i, j int) bool {
		pi := ratingSignalPriority(parts[i])
		pj := ratingSignalPriority(parts[j])

		if pi != pj {
			return pi > pj
		}

		wi := ratingSegmentSeverity(parts[i])
		wj := ratingSegmentSeverity(parts[j])

		if wi != wj {
			return wi > wj
		}

		return parts[i] < parts[j]
	})

	deduped := make([]string, 0, len(parts))
	seen := map[string]bool{}

	for _, part := range parts {
		if part == "" || seen[part] {
			continue
		}
		seen[part] = true
		deduped = append(deduped, part)
	}

	if len(deduped) == 0 {
		return ""
	}

	if len(deduped) == 1 {
		// Person alleine wird oben schon verhindert.
		return deduped[0]
	}

	return "combo:" + strings.Join(deduped, "+")
}

func addRatingLabelsFromSegment(labels map[string]bool, label string) {
	label = strings.ToLower(strings.TrimSpace(label))
	if label == "" {
		return
	}

	if strings.HasPrefix(label, "combo:") {
		raw := strings.TrimPrefix(label, "combo:")
		for _, part := range strings.Split(raw, "+") {
			addRatingLabelsFromSegment(labels, part)
		}
		return
	}

	normalized := normalizeRatingSignalLabel(label)
	if normalized == "" {
		return
	}

	labels[normalized] = true
}

func ratingSignalSetFromLabels(labels map[string]bool) ratingSignalSet {
	var set ratingSignalSet

	for label := range labels {
		ratingSignalSetAddLabel(&set, label)
	}

	return set
}

func ratingBridgeStrengthFromSet(set ratingSignalSet) float64 {
	strength := 0.0

	if set.HasPosition && set.Position > strength {
		strength = set.Position
	}
	if set.HasBody && set.Body > strength {
		strength = set.Body
	}
	if set.HasObject && set.Object > strength {
		strength = set.Object
	}
	if set.HasClothing && set.Clothing > strength {
		strength = set.Clothing
	}

	return strength
}

func ratingPositionSetFromLabels(labels map[string]bool) map[string]bool {
	out := map[string]bool{}

	for label := range labels {
		normalized := normalizeRatingSignalLabel(label)
		if strings.HasPrefix(normalized, "position:") {
			out[normalized] = true
		}
	}

	return out
}

func ratingPositionSetsConflict(a map[string]bool, b map[string]bool) bool {
	ap := ratingPositionSetFromLabels(a)
	bp := ratingPositionSetFromLabels(b)

	if len(ap) == 0 || len(bp) == 0 {
		return false
	}

	for label := range ap {
		if bp[label] {
			return false
		}
	}

	return true
}

func ratingLabelsBridgeCompatible(a map[string]bool, b map[string]bool) bool {
	if ratingPositionSetsConflict(a, b) {
		return false
	}

	for la := range a {
		na := normalizeRatingSignalLabel(la)
		if na == "" {
			continue
		}

		for lb := range b {
			nb := normalizeRatingSignalLabel(lb)
			if nb == "" {
				continue
			}

			if na == nb {
				return true
			}
		}
	}

	as := ratingSignalSetFromLabels(a)
	bs := ratingSignalSetFromLabels(b)

	// Wichtig:
	// Unterschiedliche Positionen NICHT pauschal verbinden.
	// Vorher hat "Doggy" + "Reverse Cowgirl" als kompatibel gegolten,
	// nur weil beide irgendeine Position waren.

	if as.HasBody && bs.HasBody {
		return true
	}
	if as.HasObject && bs.HasObject {
		return true
	}
	if as.HasClothing && bs.HasClothing {
		return true
	}

	return false
}

func mergeRatingActivitySegments(
	segments []aiSegmentMeta,
	maxSilentGapSec float64,
	minDurationSec float64,
) []aiSegmentMeta {
	if len(segments) == 0 {
		return nil
	}

	valid := make([]aiSegmentMeta, 0, len(segments))

	for _, s := range segments {
		if strings.TrimSpace(s.Label) == "" {
			continue
		}

		start := s.StartSeconds
		end := s.EndSeconds

		if end <= start && s.DurationSeconds > 0 {
			end = start + s.DurationSeconds
		}
		if end <= start {
			continue
		}

		labels := map[string]bool{}
		addRatingLabelsFromSegment(labels, s.Label)

		if buildRatingComboLabel(labels) == "" {
			continue
		}

		s.StartSeconds = start
		s.EndSeconds = end
		s.DurationSeconds = end - start

		if ratingSegmentSeverity(s.Label) <= 0 {
			continue
		}

		valid = append(valid, s)
	}

	if len(valid) == 0 {
		return nil
	}

	sort.SliceStable(valid, func(i, j int) bool {
		if valid[i].StartSeconds != valid[j].StartSeconds {
			return valid[i].StartSeconds < valid[j].StartSeconds
		}
		if valid[i].EndSeconds != valid[j].EndSeconds {
			return valid[i].EndSeconds < valid[j].EndSeconds
		}
		return valid[i].Label < valid[j].Label
	})

	type segmentBounds struct {
		start float64
		end   float64
		ok    bool
	}

	type activityBlock struct {
		start           float64
		end             float64
		scoreSum        float64
		scoreWeight     float64
		labels          map[string]bool
		positionWeights map[string]float64
		positionBounds  map[string]segmentBounds
		marker          float64
		markerWeight    float64
	}

	var addRatingPositionSignal func(
		weights map[string]float64,
		bounds map[string]segmentBounds,
		label string,
		weight float64,
		start float64,
		end float64,
	)

	addRatingPositionSignal = func(
		weights map[string]float64,
		bounds map[string]segmentBounds,
		label string,
		weight float64,
		start float64,
		end float64,
	) {
		label = strings.ToLower(strings.TrimSpace(label))
		if label == "" {
			return
		}

		if strings.HasPrefix(label, "combo:") {
			raw := strings.TrimPrefix(label, "combo:")
			for _, part := range strings.Split(raw, "+") {
				addRatingPositionSignal(weights, bounds, part, weight, start, end)
			}
			return
		}

		normalized := normalizeRatingSignalLabel(label)
		if !strings.HasPrefix(normalized, "position:") {
			return
		}

		if end < start {
			end = start
		}

		weights[normalized] += weight

		b := bounds[normalized]
		if !b.ok {
			b = segmentBounds{
				start: start,
				end:   end,
				ok:    true,
			}
		} else {
			if start < b.start {
				b.start = start
			}
			if end > b.end {
				b.end = end
			}
		}

		bounds[normalized] = b
	}

	effectiveRatingLabelsForBlock := func(
		labels map[string]bool,
		positionWeights map[string]float64,
	) (map[string]bool, string) {
		out := map[string]bool{}

		bestPosition := ""
		bestWeight := -1.0

		for label := range labels {
			normalized := normalizeRatingSignalLabel(label)
			if normalized == "" {
				continue
			}

			if strings.HasPrefix(normalized, "position:") {
				w := positionWeights[normalized]
				if w <= 0 {
					w = ratingSegmentSeverity(normalized)
				}

				if w > bestWeight {
					bestWeight = w
					bestPosition = normalized
				}

				continue
			}

			out[normalized] = true
		}

		if bestPosition != "" {
			out[bestPosition] = true
		}

		return out, bestPosition
	}

	segmentMarker := func(s aiSegmentMeta) float64 {
		if s.PreviewSeconds > 0 {
			return s.PreviewSeconds
		}
		if s.MarkerSeconds > 0 {
			return s.MarkerSeconds
		}
		if s.EndSeconds > s.StartSeconds {
			return (s.StartSeconds + s.EndSeconds) / 2
		}
		return s.StartSeconds
	}

	segmentMarkerWeight := func(s aiSegmentMeta) float64 {
		conf := ratingClamp01(s.Score)
		if conf <= 0 {
			conf = 0.50
		}

		sev := ratingSegmentSeverity(s.Label)
		if sev <= 0 {
			sev = 0.50
		}

		return conf * sev
	}

	newBlock := func(s aiSegmentMeta) activityBlock {
		labels := map[string]bool{}
		addRatingLabelsFromSegment(labels, s.Label)

		dur := s.EndSeconds - s.StartSeconds
		conf := ratingClamp01(s.Score)
		if conf <= 0 {
			conf = 0.50
		}

		positionWeights := map[string]float64{}
		positionBounds := map[string]segmentBounds{}

		addRatingPositionSignal(
			positionWeights,
			positionBounds,
			s.Label,
			conf*math.Max(1, dur),
			s.StartSeconds,
			s.EndSeconds,
		)

		marker := segmentMarker(s)
		markerWeight := segmentMarkerWeight(s)

		return activityBlock{
			start:           s.StartSeconds,
			end:             s.EndSeconds,
			scoreSum:        conf * dur,
			scoreWeight:     dur,
			labels:          labels,
			positionWeights: positionWeights,
			positionBounds:  positionBounds,
			marker:          marker,
			markerWeight:    markerWeight,
		}
	}

	finishBlock := func(b activityBlock) (aiSegmentMeta, bool) {
		dur := b.end - b.start
		if dur <= 0 {
			return aiSegmentMeta{}, false
		}

		effectiveLabels, bestPosition := effectiveRatingLabelsForBlock(b.labels, b.positionWeights)
		label := buildRatingComboLabel(effectiveLabels)
		if label == "" {
			return aiSegmentMeta{}, false
		}

		sev := ratingSegmentSeverity(label)

		start := b.start

		// Wenn der finale Block eine Position trägt, soll die Anzeige/der Klick
		// beim ersten echten Auftreten dieser Position starten — nicht schon bei
		// früheren Body-/Object-Signalen aus demselben Aktivitätsblock.
		if bestPosition != "" {
			if bounds, ok := b.positionBounds[bestPosition]; ok && bounds.ok {
				if bounds.start > start {
					start = bounds.start
				}
			}
		}

		dur = b.end - start
		if dur <= 0 {
			return aiSegmentMeta{}, false
		}

		// Kurze Segmente dürfen bleiben, wenn sie stark genug sind.
		if dur < minDurationSec && sev < 0.72 {
			return aiSegmentMeta{}, false
		}

		score := 0.0
		if b.scoreWeight > 0 {
			score = b.scoreSum / b.scoreWeight
		}
		if score <= 0 {
			score = 0.50
		}

		return aiSegmentMeta{
			Label:           label,
			Score:           ratingClamp01(score),
			StartSeconds:    start,
			EndSeconds:      b.end,
			DurationSeconds: dur,
			AutoSelected:    true,
			Position:        segmentPositionFromAnalyzeLabel(label),
			Tags:            segmentTagsFromAnalyzeLabel(label),
			MarkerSeconds:   b.marker,
			PreviewSeconds:  b.marker,
		}, true
	}

	out := make([]aiSegmentMeta, 0, len(valid))
	cur := newBlock(valid[0])

	for i := 1; i < len(valid); i++ {
		n := valid[i]

		gap := n.StartSeconds - cur.end

		shouldBridge := gap <= maxSilentGapSec

		if !shouldBridge && gap <= ratingBridgeStrongGapSec {
			nextLabels := map[string]bool{}
			addRatingLabelsFromSegment(nextLabels, n.Label)

			curSet := ratingSignalSetFromLabels(cur.labels)
			nextSet := ratingSignalSetFromLabels(nextLabels)

			curBridgeStrength := ratingBridgeStrengthFromSet(curSet)
			nextBridgeStrength := ratingBridgeStrengthFromSet(nextSet)

			curDur := cur.end - cur.start
			nextDur := n.EndSeconds - n.StartSeconds

			shouldBridge =
				ratingLabelsBridgeCompatible(cur.labels, nextLabels) &&
					curBridgeStrength >= 0.65 &&
					nextBridgeStrength >= 0.65 &&
					(curDur >= 8 || nextDur >= 8)
		}

		if !shouldBridge {
			if finished, ok := finishBlock(cur); ok {
				out = append(out, finished)
			}

			cur = newBlock(n)
			continue
		}

		if n.StartSeconds < cur.start {
			cur.start = n.StartSeconds
		}
		if n.EndSeconds > cur.end {
			cur.end = n.EndSeconds
		}

		dur := n.EndSeconds - n.StartSeconds
		if dur > 0 {
			conf := ratingClamp01(n.Score)
			if conf <= 0 {
				conf = 0.50
			}

			cur.scoreSum += conf * dur
			cur.scoreWeight += dur

			addRatingPositionSignal(
				cur.positionWeights,
				cur.positionBounds,
				n.Label,
				conf*math.Max(1, dur),
				n.StartSeconds,
				n.EndSeconds,
			)
		}

		nextMarkerWeight := segmentMarkerWeight(n)
		if nextMarkerWeight > cur.markerWeight {
			cur.markerWeight = nextMarkerWeight
			cur.marker = segmentMarker(n)
		}

		addRatingLabelsFromSegment(cur.labels, n.Label)
	}

	if finished, ok := finishBlock(cur); ok {
		out = append(out, finished)
	}

	return out
}

func prepareAIRatingSegments(segments []aiSegmentMeta) []aiSegmentMeta {
	return mergeRatingActivitySegments(
		segments,
		ratingMaxSilentGapSec,
		ratingMinSegmentDurationSec,
	)
}

func ratingConfidenceWeight(conf float64) float64 {
	conf = ratingClamp01(conf)

	// Confidence soll relevant sein, aber schlechte Scores nicht komplett töten.
	n := ratingSmoothStep((conf - 0.25) / 0.70)

	return 0.58 + 0.42*n
}

func ratingLinearGate(value float64, start float64, full float64) float64 {
	if full <= start {
		if value >= full {
			return 1
		}
		return 0
	}

	return ratingClamp01((value - start) / (full - start))
}

func ratingExcellenceBonus(
	peakQuality float64,
	positionEffectiveWeighted float64,
	positionDensity float64,
	weightedCoverageRatio float64,
	totalFlagged float64,
	longest float64,
	avgConfidence float64,
	segmentsPerMinute float64,
	n int,
) float64 {
	// Kein pauschaler Score-Shift:
	// Der Bonus darf nur greifen, wenn wirklich mehrere starke Signale vorhanden sind.
	if n < 2 {
		return 0
	}
	if positionEffectiveWeighted <= 0 {
		return 0
	}
	if totalFlagged < 12.0 {
		return 0
	}
	if peakQuality < 0.68 {
		return 0
	}
	if avgConfidence < 0.42 {
		return 0
	}

	peakGate := ratingLinearGate(peakQuality, 0.68, 0.90)
	positionGate := ratingLinearGate(positionDensity, 2.20, 7.00)
	coverageGate := ratingLinearGate(weightedCoverageRatio, 0.045, 0.160)
	durationGate := ratingLinearGate(totalFlagged, 12.0, 90.0)
	longestGate := ratingLinearGate(longest, 8.0, 45.0)
	confGate := ratingLinearGate(avgConfidence, 0.42, 0.78)
	frequencyGate := ratingLinearGate(segmentsPerMinute, 0.25, 1.00)

	bonus :=
		0.030*peakGate +
			0.022*positionGate +
			0.016*coverageGate +
			0.012*durationGate +
			0.012*longestGate +
			0.010*confGate +
			0.006*frequencyGate

	// Maximal +8.5 Scorepunkte.
	// Dadurch werden starke 72-79 Scores 5-Sterne-fähig,
	// aber mittelmäßige Scores springen nicht einfach pauschal hoch.
	if bonus > 0.085 {
		bonus = 0.085
	}

	return bonus
}

func starsFromHighlightScore(score float64) int {
	switch {
	case score < 18:
		return 1
	case score < 38:
		return 2
	case score < 60:
		return 3
	case score < 80:
		return 4
	default:
		return 5
	}
}

func ratingUsernameFromVideoPath(videoPath string) string {
	id := strings.TrimSpace(assetIDFromVideoPath(videoPath))
	if id == "" {
		return ""
	}

	user := strings.ToLower(strings.TrimSpace(modelNameFromFilename(id)))
	if user != "" && user != "unknown" {
		return user
	}

	// Fallback nur, wenn die ID nicht wie ein kompletter Dateiname mit Timestamp aussieht.
	if !strings.Contains(id, "__") {
		return strings.ToLower(strings.TrimSpace(id))
	}

	return ""
}

func ratingLogSubject(username string) string {
	username = strings.ToLower(strings.TrimSpace(username))
	if username == "" || username == "unknown" {
		return "[rating]"
	}

	return "[" + username + "]"
}

func computeHighlightRating(segments []aiSegmentMeta, durationSec float64) *aiRatingMeta {
	return computeHighlightRatingWithUsername(segments, durationSec, "")
}

func computeHighlightRatingForVideo(segments []aiSegmentMeta, durationSec float64, videoPath string) *aiRatingMeta {
	return computeHighlightRatingWithUsername(segments, durationSec, ratingUsernameFromVideoPath(videoPath))
}

func computeHighlightRatingWithUsername(segments []aiSegmentMeta, durationSec float64, username string) *aiRatingMeta {
	r := &aiRatingMeta{
		Score: 0,
		Stars: 1,
	}

	if durationSec <= 0 || len(segments) == 0 {
		return r
	}

	videoMinutes := math.Max(durationSec/60.0, 0.25)

	var totalFlagged float64
	var totalWeighted float64

	var positionEffectiveWeighted float64
	var contextEffectiveWeighted float64
	var peakQuality float64

	var longest float64
	var confSum float64
	var n int

	for _, s := range segments {
		segDur := s.DurationSeconds
		if segDur <= 0 {
			segDur = s.EndSeconds - s.StartSeconds
		}
		if segDur <= 0 {
			continue
		}

		sev := ratingSegmentSeverity(s.Label)
		if sev <= 0 {
			appLogf("🧪 [rating] skip zero severity label=%q normalized=%q", s.Label, normalizeRatingSignalLabel(s.Label))
			continue
		}

		conf := ratingClamp01(s.Score)
		if conf <= 0 {
			conf = 0.50
		}

		confWeight := ratingConfidenceWeight(conf)
		quality := sev * confWeight

		if quality <= 0 {
			continue
		}

		effectiveDur := ratingEffectiveDurationSeconds(segDur)
		weightedDur := segDur * quality
		effectiveWeightedDur := effectiveDur * quality

		totalFlagged += segDur
		totalWeighted += weightedDur

		set := ratingSignalSetFromLabel(s.Label)
		if set.HasPosition {
			positionEffectiveWeighted += effectiveWeightedDur
		} else {
			contextEffectiveWeighted += effectiveWeightedDur
		}

		if quality > peakQuality {
			peakQuality = quality
		}

		confSum += conf
		n++

		if segDur > longest {
			longest = segDur
		}
	}

	if n == 0 {
		appLogf("⚠️ %s rating result is zero because all segments were skipped", ratingLogSubject(username))
		return r
	}

	coverageRatio := ratingClamp01(totalFlagged / durationSec)
	weightedCoverageRatio := ratingClamp01(totalWeighted / durationSec)
	segmentsPerMinute := float64(n) / videoMinutes
	avgConfidence := confSum / float64(n)

	positionDensity := positionEffectiveWeighted / videoMinutes
	contextDensity := contextEffectiveWeighted / videoMinutes

	peakNorm := ratingSmoothStep(peakQuality)
	positionDensityNorm := ratingSoftCap(positionDensity, 5.5)
	contextDensityNorm := ratingSoftCap(contextDensity, 8.5)
	coverageNorm := ratingSoftCap(weightedCoverageRatio, 0.20)
	frequencyNorm := ratingSoftCap(segmentsPerMinute, 1.25)
	longestNorm := ratingSoftCap(longest, 24.0)
	confNorm := ratingSmoothStep((avgConfidence - 0.30) / 0.65)

	raw :=
		0.32*peakNorm +
			0.25*positionDensityNorm +
			0.17*contextDensityNorm +
			0.12*coverageNorm +
			0.06*longestNorm +
			0.04*frequencyNorm +
			0.04*confNorm

	// Ohne Position darf es trotzdem gut werden, aber nicht automatisch 5 Sterne.
	if positionEffectiveWeighted <= 0 {
		raw = math.Min(raw, 0.76)
	}

	// Sehr wenig Material nicht überbewerten.
	if totalFlagged < 5.0 && n <= 1 {
		raw = math.Min(raw, 0.44)
	}

	excellenceBonus := ratingExcellenceBonus(
		peakQuality,
		positionEffectiveWeighted,
		positionDensity,
		weightedCoverageRatio,
		totalFlagged,
		longest,
		avgConfidence,
		segmentsPerMinute,
		n,
	)

	raw = ratingClamp01(raw + excellenceBonus)

	score := ratingRound(raw*100, 1)

	r.Score = score
	r.Stars = starsFromHighlightScore(score)
	r.Segments = n
	r.SegmentsPerMinute = ratingRound(segmentsPerMinute, 2)
	r.FlaggedSeconds = ratingRound(totalFlagged, 2)
	r.WeightedFlaggedSeconds = ratingRound(totalWeighted, 2)
	r.CoverageRatio = ratingRound(coverageRatio, 4)
	r.WeightedCoverageRatio = ratingRound(weightedCoverageRatio, 4)
	r.LongestSegmentSeconds = ratingRound(longest, 2)
	r.AvgConfidence = ratingRound(avgConfidence, 3)

	appLogf(
		"✅ %s rating result score=%.1f stars=%d bonus=%.1f segments=%d flagged=%.2f weighted=%.2f coverage=%.4f weightedCoverage=%.4f longest=%.2f avgConf=%.3f",
		ratingLogSubject(username),
		r.Score,
		r.Stars,
		ratingRound(excellenceBonus*100, 1),
		r.Segments,
		r.FlaggedSeconds,
		r.WeightedFlaggedSeconds,
		r.CoverageRatio,
		r.WeightedCoverageRatio,
		r.LongestSegmentSeconds,
		r.AvgConfidence,
	)

	return r
}