package platform

import (
	"path/filepath"
	"testing"
	"time"
)

func TestParseFanSpeeds(t *testing.T) {
	raw := "FAN1 | 2400.000 | RPM | ok\nFAN2 | 1800 RPM | ok | ok\nFAN3 | na | RPM | ns\n"
	got := parseFanSpeeds(raw)
	if len(got) != 2 {
		t.Fatalf("fans=%d want 2 (%v)", len(got), got)
	}
	if got[0].Name != "FAN1" || got[0].RPM != 2400 {
		t.Fatalf("fan0=%+v", got[0])
	}
	if got[1].Name != "FAN2" || got[1].RPM != 1800 {
		t.Fatalf("fan1=%+v", got[1])
	}
}

func TestFirstFanInputValue(t *testing.T) {
	feature := map[string]any{
		"fan1_input": 9200.0,
	}
	got, ok := firstFanInputValue(feature)
	if !ok || got != 9200 {
		t.Fatalf("got=%v ok=%v", got, ok)
	}
}

func TestParseFanDutyCyclePctSensorsJSON(t *testing.T) {
	raw := []byte(`{
		"chip0": {
			"fan1": {"input": 9000},
			"pwm1": {"input": 128},
			"pwm1_enable": {"input": 1}
		},
		"chip1": {
			"pwm2": {"input": 64}
		}
	}`)

	got, ok := parseFanDutyCyclePctSensorsJSON(raw)
	if !ok {
		t.Fatalf("expected duty cycle telemetry to be parsed")
	}
	if got < 57 || got > 58 {
		t.Fatalf("got=%v want ~57.1", got)
	}
}

func TestEstimateFanDutyCyclePctFromObservation(t *testing.T) {
	t.Parallel()

	oldPath := fanObservationStatePath
	oldState := fanObservation
	oldInit := fanObservationInit
	oldCandidates := fanPeakCandidates
	fanObservationStatePath = filepath.Join(t.TempDir(), "fan-observation.json")
	fanObservation = fanObservationState{}
	fanObservationInit = false
	fanPeakCandidates = make(map[string]fanPeakCandidate)
	t.Cleanup(func() {
		fanObservationStatePath = oldPath
		fanObservation = oldState
		fanObservationInit = oldInit
		fanPeakCandidates = oldCandidates
	})

	start := time.Unix(100, 0)
	updateFanObservation([]FanReading{{Name: "FAN1", RPM: 5000}}, start)
	if _, ok := estimateFanDutyCyclePctFromObservation([]FanReading{{Name: "FAN1", RPM: 2500}}); ok {
		t.Fatalf("single-sample spike should not establish observed max")
	}

	updateFanObservation([]FanReading{{Name: "FAN1", RPM: 5200}}, start.Add(500*time.Millisecond))
	updateFanObservation([]FanReading{{Name: "FAN1", RPM: 5100}}, start.Add(1500*time.Millisecond))

	got, ok := estimateFanDutyCyclePctFromObservation([]FanReading{{Name: "FAN1", RPM: 2600}})
	if !ok {
		t.Fatalf("expected estimated duty cycle from persisted observed max")
	}
	if got < 43 || got > 44 {
		t.Fatalf("got=%v want ~43.3", got)
	}

	fanObservation = fanObservationState{}
	fanObservationInit = false
	fanPeakCandidates = make(map[string]fanPeakCandidate)
	got, ok = estimateFanDutyCyclePctFromObservation([]FanReading{{Name: "FAN1", RPM: 2600}})
	if !ok {
		t.Fatalf("expected persisted observed max to be reloaded from disk")
	}
	if got < 43 || got > 44 {
		t.Fatalf("reloaded got=%v want ~43.3", got)
	}
}

func TestParseDCMIPowerReading(t *testing.T) {
	raw := `
Instantaneous power reading:                   512 Watts
Minimum during sampling period:               498 Watts
`
	if got := parseDCMIPowerReading(raw); got != 512 {
		t.Fatalf("parseDCMIPowerReading()=%v want 512", got)
	}
}

func TestEffectiveSystemPowerReading(t *testing.T) {
	now := time.Now()
	cache := cachedPowerReading{Value: 480, UpdatedAt: now.Add(-5 * time.Second)}

	got, updated := effectiveSystemPowerReading(cache, 0, "", "", "", now)
	if got != 480 {
		t.Fatalf("got=%v want cached 480", got)
	}
	if updated.Value != 480 {
		t.Fatalf("updated=%+v", updated)
	}

	got, updated = effectiveSystemPowerReading(cache, 530, "dcmi", "fallback", "test", now)
	if got != 530 {
		t.Fatalf("got=%v want 530", got)
	}
	if updated.Value != 530 {
		t.Fatalf("updated=%+v", updated)
	}

	expired := cachedPowerReading{Value: 480, UpdatedAt: now.Add(-systemPowerHoldTTL - time.Second)}
	got, _ = effectiveSystemPowerReading(expired, 0, "", "", "", now)
	if got != 0 {
		t.Fatalf("expired cache returned %v want 0", got)
	}
}