package main

import (
	"image/color"
	"image/png"
	"log"
	"math"
	"math/rand"
	"os"
	"strconv"
	"time"

	"github.com/hajimehoshi/ebiten/v2"
)

type Game struct {
	points          []*Position
	preScreens      []*ColorArray
	screen          *ebiten.Image
	pressCountEnter int
	pressCountSpace int
}

func (g *Game) NewImage() {
	image := NewColorArray()
	for i := 0; i < 3; i++ {
		x, y := rand.Intn(screenHeight), rand.Intn(screenWidth)
		g.points[i] = &Position{x, y}
	}
	for x := 0; x < screenWidth; x++ {
		for y := 0; y < screenHeight; y++ {
			c := make([]uint16, 3)
			for i := 0; i < 3; i++ {
				p := g.points[i]
				if p.X != x || p.Y != y {
					v := math.Abs(p.Dist(&Position{x, y}))
					c[i] = function.Func(v)
				} else {
					c[0] = 65535
					c[1] = 65535
					c[2] = 65535
					break
				}
			}
			image.Set(x, y, color.RGBA64{c[0], c[1], c[2], 255})
		}
	}
	g.preScreens = append(g.preScreens, image)
}

func (gm *Game) Init() {
	for i := 0; i < layerCount; i++ {
		gm.NewImage()
	}

	for x := 0; x < screenWidth; x++ {
		for y := 0; y < screenHeight; y++ {
			var r, g, b int64 = 0, 0, 0
			for i := 0; i < layerCount; i++ {
				R, G, B, _ := gm.preScreens[i].At(x, y).RGBA()
				r += int64(R)
				g += int64(G)
				b += int64(B)
			}
			r /= int64(layerCount)
			g /= int64(layerCount)
			b /= int64(layerCount)
			gm.screen.Set(x, y, color.RGBA64{uint16(r), uint16(g), uint16(b), 65535})
		}
	}
}

func (g *Game) ReInit() {
	g.points = make([]*Position, 3)
	g.preScreens = make([]*ColorArray, 0)
	g.screen = ebiten.NewImage(screenWidth, screenHeight)
	g.Init()
}

func NewGame() *Game {
	gm := &Game{
		make([]*Position, 3),
		make([]*ColorArray, 0),
		ebiten.NewImage(screenWidth, screenHeight),
		0,
		0,
	}
	gm.Init()
	return gm
}

func (g *Game) Update() error {
	if ebiten.IsKeyPressed(ebiten.KeyEnter) && g.pressCountEnter == 0 {
		file, err := os.Create(strconv.FormatInt(time.Now().Unix(), 10) + ".png")
		if err != nil {
			return err
		}
		defer file.Close()
		err = png.Encode(file, g.screen)
		if err != nil {
			return err
		}

		g.pressCountEnter++
	} else if !ebiten.IsKeyPressed(ebiten.KeyEnter) && g.pressCountEnter > 0 {
		g.pressCountEnter = 0
	}

	if ebiten.IsKeyPressed(ebiten.KeySpace) && g.pressCountSpace == 0 {
		g.ReInit()
		g.pressCountSpace++
	} else if !ebiten.IsKeyPressed(ebiten.KeySpace) && g.pressCountSpace > 0 {
		g.pressCountSpace = 0
	}
	return nil
}

func (g *Game) Draw(screen *ebiten.Image) {
	screen.DrawImage(g.screen, nil)
}

func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
	return screenWidth, screenHeight
}

func main() {
	g := NewGame()
	ebiten.SetWindowSize(windowWidth, windowHeight)
	ebiten.SetWindowTitle("XVisuals")
	if err := ebiten.RunGame(g); err != nil {
		log.Fatal(err)
	}
}