package ride

import (
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestBacktestEligibilityExcludesShortDistances(t *testing.T) {
	short := StoredRide{FitPath: "fit", DistanceM: 10_000 - 1, ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTraining}
	minimum := StoredRide{FitPath: "fit", DistanceM: 10_000, ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTraining}

	assert.True(t, isBacktestEligible(short))
	assert.True(t, isBacktestEligible(minimum))
}

func TestBacktestEligibilityExcludesLowMovingRatio(t *testing.T) {
	low := StoredRide{FitPath: "fit", DistanceM: 10_000, ExternalMovingTimeS: 7_999, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTraining}
	boundary := StoredRide{FitPath: "fit", DistanceM: 10_000, ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTraining}
	noElapsed := StoredRide{FitPath: "fit", DistanceM: 10_000, ExternalMovingTimeS: 1, BikeType: BikeTypeRoad, RideType: RideTypeTraining}

	assert.True(t, isBacktestEligible(low))
	assert.True(t, isBacktestEligible(boundary))
	assert.False(t, isBacktestEligible(noElapsed))
}

func TestBacktestEligibilityExcludesUncategorisedAndIndoorTransport(t *testing.T) {
	base := StoredRide{FitPath: "fit", ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTraining}
	uncategorised := StoredRide{FitPath: "fit", ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000}
	indoor := StoredRide{FitPath: "fit", ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeIndoor}
	transport := StoredRide{FitPath: "fit", ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeRoad, RideType: RideTypeTransport}
	race := StoredRide{FitPath: "fit", ExternalMovingTimeS: 8_000, ElapsedTimeS: 10_000, BikeType: BikeTypeMTB, RideType: RideTypeRace}

	assert.True(t, isBacktestEligible(base))
	assert.False(t, isBacktestEligible(uncategorised))
	assert.False(t, isBacktestEligible(indoor))
	assert.False(t, isBacktestEligible(transport))
	assert.True(t, isBacktestEligible(race))
}

func TestBacktestStatsUseUnroundedSamples(t *testing.T) {
	absErrors := []float64{0, 0.1, 0.1}

	assert.InDelta(t, 1.0/15, meanAbsErr(absErrors), 1e-12)
	assert.InDelta(t, 1.0/30, stdErrAbsErr(absErrors), 1e-12)
}

func TestErrorDistributionUsesNearestRank(t *testing.T) {
	distribution := errorDistribution([]float64{1, 2, 3, 4}, []float64{50, 75, 99})

	assert.Equal(t, 2.0, distribution[50])
	assert.Equal(t, 3.0, distribution[75])
	assert.Equal(t, 4.0, distribution[99])
}