package lgraya

import (
	"math"
	"testing"

	"smariot.com/color/internal/helper"
)

func eq(c0, c1 Color) bool {
	return helper.EqFloat64SliceFuzzy(
		[]float64{c0.Y, c0.A},
		[]float64{c1.Y, c1.A},
	)
}

func midpoint(c0, c1 Color) Color {
	return Color{(c0.Y + c1.Y) / 2, (c0.A + c1.A) / 2}
}

func TestModel(t *testing.T) {
	helper.TestModel(t, false, true, Model, eq, []helper.ConvertTest[Color]{
		// These is a very illegal colour. If it makes it through
		// unchanged, we can be reasonably confident no colour space conversions were
		// attempted.
		{
			Name: "passthrough +inf",
			In:   Color{math.Inf(1), 0},
			Out:  Color{math.Inf(1), 0},
		}, {
			Name: "passthrough +inf",
			In:   Color{math.Inf(-1), math.NaN()},
			Out:  Color{math.Inf(-1), math.NaN()},
		}, {
			Name: "passthrough nan",
			In:   Color{math.NaN(), math.Inf(1)},
			Out:  Color{math.NaN(), math.Inf(1)},
		},
	})
}

func distance(a, b Color) float64 {
	d := Distance(a, b)
	dSqr := DistanceSqr(a, b)
	if !helper.EqFloat64Fuzzy(d*d, dSqr) {
		panic("Distance and DistanceSqr are not equivalent")
	}
	return d
}

func TestDistance(t *testing.T) {
	helper.TestDistance(t, false, true, midpoint, distance, Model)
}