package resize

import (
	"image"
	"image/color"
	"runtime"
	"testing"
)

var img = image.NewGray16(image.Rect(0, 0, 3, 3))

func init() {
	runtime.GOMAXPROCS(runtime.NumCPU())
	img.Set(1, 1, color.White)
}

func Test_Nearest(t *testing.T) {
	m := Resize(6, 0, img, NearestNeighbor)
	if m.At(2, 2) == m.At(3, 3) {
		t.Fail()
	}
}

func Test_Param1(t *testing.T) {
	m := Resize(0, 0, img, NearestNeighbor)
	if m.Bounds() != img.Bounds() {
		t.Fail()
	}
}

func Test_Param2(t *testing.T) {
	m := Resize(100, 0, img, NearestNeighbor)
	if m.Bounds() != image.Rect(0, 0, 100, 100) {
		t.Fail()
	}
}

func Test_ZeroImg(t *testing.T) {
	zeroImg := image.NewGray16(image.Rect(0, 0, 0, 0))

	m := Resize(0, 0, zeroImg, NearestNeighbor)
	if m.Bounds() != zeroImg.Bounds() {
		t.Fail()
	}
}

func Benchmark_BigResize(b *testing.B) {
	var m image.Image
	for i := 0; i < b.N; i++ {
		m = Resize(1000, 1000, img, Lanczos3)
	}
	m.At(0, 0)
}

func Benchmark_Reduction(b *testing.B) {
	largeImg := image.NewRGBA(image.Rect(0, 0, 1000, 1000))

	var m image.Image
	for i := 0; i < b.N; i++ {
		m = Resize(300, 300, largeImg, Lanczos3)
	}
	m.At(0, 0)
}