package dithering

import (
	"image"
	"image/color"
	"image/png"
	"math/rand"
	"os"
	"os/exec"
	"testing"
	"time"
	"reflect"

	"git.nkpl.cc/twocookedfaggots/imageutils"
)

func init() {
	rand.Seed(time.Now().UnixNano())
}

const factor = 0.75

func callImage(img image.Image) {
	for y := 0; y < img.Bounds().Dy(); y++ {
		for x := 0; x < img.Bounds().Dx(); x++ {
			_ = img.At(x, y)
		}
	}
}

func TestGrid(t *testing.T) {
	command := exec.Command("imv", "-")
	w, err := command.StdinPipe()
	if err != nil {
		t.Fatal(err)
	}
	err = command.Start()
	if err != nil {
		t.Fatal(err)
	}

	n := uint8(rand.Int() % 256)
	t.Log(n)
	img := imageutils.Scale(grid{color.Gray{n}, factor}, 1<<6)
	err = png.Encode(w, img)
	if err != nil {
		t.Fatal(err)
	}

	callImage(grid{color.Gray{4}, factor})
	callImage(grid{color.Gray{0}, factor})
}

func TestDithering(t *testing.T) {
	r, err := os.Open("/home/potassium/documents/wallpaper/8.png")
	if err != nil {
		t.Fatal(err)
	}
	defer r.Close()

	w, err := os.Create("sample.png")
	if err != nil {
		t.Fatal(err)
	}
	defer w.Close()

	img, err := png.Decode(r)
	if err != nil {
		t.Fatal(err)
	}

	err = png.Encode(w, Dithering{img, factor})
	if err != nil {
		t.Fatal(err)
	}
}

func TestRangeStruct(t *testing.T){
	s := Dithering{image.Rectangle{},0}
	value := reflect.ValueOf(s)
	if value.Kind() == reflect.Ptr {
		value = value.Elem()
	}
	if value.Kind() != reflect.Struct {
		t.Log("Provided value is not a struct")
	}
	tp := value.Type()
	for i := 0; i < value.NumField(); i++ {
		fieldName := tp.Field(i).Name
		fieldValue := value.Field(i)

		if !fieldValue.CanInterface() {
			t.Logf("Field %s is unexported\n", fieldName)
			continue
		}
		if fieldValue.Kind() == reflect.Ptr {
			fieldValue = fieldValue.Elem()
		}
		/*
		if fieldValue.Kind() == reflect.Interface {
			fieldValue = fieldValue.Elem()
		}
		*/


		actualValue := fieldValue.Interface()
		switch v := actualValue.(type) {
		case float64:
			t.Logf("Field '%s' is a float64.\n", fieldName)
		case image.Image:
			t.Logf("Field '%s' is a image.Image. Value: %q\n", fieldName, v) 
		default:
			t.Logf("Field '%s' has an unhandled type: %T\n", fieldName, v)
		}
	}
}