refactor: simplify detector config and confidence scoring

cmd/sdrd/main.go

@@ -314,19 +314,7 @@ func main() {
 	defer eventFile.Close()
 	eventMu := &sync.RWMutex{}
 
-	det := detector.New(cfg.Detector.ThresholdDb, cfg.SampleRate, cfg.FFTSize,
-		time.Duration(cfg.Detector.MinDurationMs)*time.Millisecond,
-		time.Duration(cfg.Detector.HoldMs)*time.Millisecond,
-		cfg.Detector.EmaAlpha,
-		cfg.Detector.HysteresisDb,
-		cfg.Detector.MinStableFrames,
-		time.Duration(cfg.Detector.GapToleranceMs)*time.Millisecond,
-		cfg.Detector.CFARMode,
-		cfg.Detector.CFARGuardCells,
-		cfg.Detector.CFARTrainCells,
-		cfg.Detector.CFARRank,
-		cfg.Detector.CFARScaleDb,
-		cfg.Detector.CFARWrapAround)
+	det := detector.New(cfg.Detector, cfg.SampleRate, cfg.FFTSize)
 
 	window := fftutil.Hann(cfg.FFTSize)
 	h := newHub()
@@ -458,19 +446,7 @@ func main() {
 			var newDet *detector.Detector
 			var newWindow []float64
 			if detChanged {
-				newDet = detector.New(next.Detector.ThresholdDb, next.SampleRate, next.FFTSize,
-					time.Duration(next.Detector.MinDurationMs)*time.Millisecond,
-					time.Duration(next.Detector.HoldMs)*time.Millisecond,
-					next.Detector.EmaAlpha,
-					next.Detector.HysteresisDb,
-					next.Detector.MinStableFrames,
-					time.Duration(next.Detector.GapToleranceMs)*time.Millisecond,
-					next.Detector.CFARMode,
-					next.Detector.CFARGuardCells,
-					next.Detector.CFARTrainCells,
-					next.Detector.CFARRank,
-					next.Detector.CFARScaleDb,
-					next.Detector.CFARWrapAround)
+				newDet = detector.New(next.Detector, next.SampleRate, next.FFTSize)
 			}
 			if windowChanged {
 				newWindow = fftutil.Hann(next.FFTSize)

internal/classifier/rules.go

@@ -114,15 +114,27 @@ func top2(scores map[SignalClass]float64) (SignalClass, float64, SignalClass, fl
 	var best, second SignalClass
 	bestScore := 0.0
 	secondScore := 0.0
+	better := func(k SignalClass, v float64, cur SignalClass, curV float64) bool {
+		if v > curV {
+			return true
+		}
+		if v < curV {
+			return false
+		}
+		if cur == "" {
+			return true
+		}
+		return string(k) < string(cur)
+	}
 	for k, v := range scores {
-		if v > bestScore {
+		if better(k, v, best, bestScore) {
 			second = best
 			secondScore = bestScore
 			best = k
 			bestScore = v
 			continue
 		}
-		if v > secondScore {
+		if k != best && better(k, v, second, secondScore) {
 			second = k
 			secondScore = v
 		}

internal/detector/detector.go

@@ -7,6 +7,7 @@ import (
 
 	"sdr-visual-suite/internal/cfar"
 	"sdr-visual-suite/internal/classifier"
+	"sdr-visual-suite/internal/config"
 )
 
 type Event struct {
@@ -68,7 +69,21 @@ type Signal struct {
 	Class    *classifier.Classification `json:"class,omitempty"`
 }
 
-func New(thresholdDb float64, sampleRate int, fftSize int, minDur, hold time.Duration, emaAlpha, hysteresis float64, minStable int, gapTolerance time.Duration, cfarMode string, cfarGuard, cfarTrain, cfarRank int, cfarScaleDb float64, cfarWrap bool) *Detector {
+func New(detCfg config.DetectorConfig, sampleRate int, fftSize int) *Detector {
+	minDur := time.Duration(detCfg.MinDurationMs) * time.Millisecond
+	hold := time.Duration(detCfg.HoldMs) * time.Millisecond
+	gapTolerance := time.Duration(detCfg.GapToleranceMs) * time.Millisecond
+	emaAlpha := detCfg.EmaAlpha
+	hysteresis := detCfg.HysteresisDb
+	minStable := detCfg.MinStableFrames
+	cfarMode := detCfg.CFARMode
+	cfarGuard := detCfg.CFARGuardCells
+	cfarTrain := detCfg.CFARTrainCells
+	cfarRank := detCfg.CFARRank
+	cfarScaleDb := detCfg.CFARScaleDb
+	cfarWrap := detCfg.CFARWrapAround
+	thresholdDb := detCfg.ThresholdDb
+
 	if minDur <= 0 {
 		minDur = 250 * time.Millisecond
 	}

internal/detector/detector_test.go

@@ -3,10 +3,26 @@ package detector
 import (
 	"testing"
 	"time"
+
+	"sdr-visual-suite/internal/config"
 )
 
 func TestDetectorCreatesEvent(t *testing.T) {
-	d := New(-10, 1000, 10, 1*time.Millisecond, 10*time.Millisecond, 0.2, 3, 1, 10*time.Millisecond, "OFF", 2, 16, 24, 6, true)
+	d := New(config.DetectorConfig{
+		ThresholdDb:     -10,
+		MinDurationMs:   1,
+		HoldMs:          10,
+		EmaAlpha:        0.2,
+		HysteresisDb:    3,
+		MinStableFrames: 1,
+		GapToleranceMs:  10,
+		CFARMode:        "OFF",
+		CFARGuardCells:  2,
+		CFARTrainCells:  16,
+		CFARRank:        24,
+		CFARScaleDb:     6,
+		CFARWrapAround:  true,
+	}, 1000, 10)
 	center := 0.0
 	spectrum := []float64{-30, -30, -30, -5, -5, -30, -30, -30, -30, -30}
 	now := time.Now()

web/app.js

@@ -507,7 +507,10 @@ function updateHeroMetrics() {
   metricSource.textContent = stats.last_sample_ago_ms >= 0 ? `${stats.last_sample_ago_ms} ms` : 'n/a';
 
   const gpuText = gpuInfo.active ? 'GPU active' : (gpuInfo.available ? 'GPU ready' : 'GPU n/a');
-  metaLine.textContent = `${fmtMHz(latest.center_hz, 3)} · ${fmtHz(span)} span · ${gpuText}`;
+  const thresholdInfo = Array.isArray(latest.thresholds) && latest.thresholds.length
+    ? `CFAR on · noise ${(Number.isFinite(latest.noise_floor) ? latest.noise_floor.toFixed(1) : 'n/a')} dB`
+    : `CFAR off · noise ${(Number.isFinite(latest.noise_floor) ? latest.noise_floor.toFixed(1) : 'n/a')} dB`;
+  metaLine.textContent = `${fmtMHz(latest.center_hz, 3)} · ${fmtHz(span)} span · ${thresholdInfo} · ${gpuText}`;
   heroSubtitle.textContent = `${latest.signals?.length || 0} live signals · ${events.length} recent events tracked`;
 
   healthBuffer.textContent = String(stats.buffer_samples ?? '-');