func main() {
	// 設(shè)置窗口大小是
	ebiten.SetWindowSize(880, 520)
	// 設(shè)置窗口頭部，顯示 飛翔的小鳥
	ebiten.SetWindowTitle("飛翔的小鳥")

	// 運行游戲
	err := ebiten.RunGame(&game);
	if err != nil {
		log.Fatal(err)
	}
}

/*
	Layout()函數(shù)的返回值表示顯示窗口里面邏輯上屏幕的大小
	官網(wǎng)上說參數(shù)outsideWidth和outsideHeight是顯示在桌面的窗口大小
	這里是固定大小
*/
func (g *Game) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
	return 880, 520
}

func (g *Game) Update(screen *ebiten.Image) error {
	g.DrawBegin(screen)
	return nil
}

func (g *Game) DrawBegin(screen *ebiten.Image) {
	DrawBackGround(screen)
}
}

func DrawBackGround(screen *ebiten.Image){
	//  背景顏色
	screen.Fill(color.RGBA{78, 192, 202,255})
	//  繪制地板
	f1, err := os.Open("imgs/ground.png")
	if err != nil {
		log.Fatal(err)
	}
	img1, err := png.Decode(f1)
	if err != nil {
		log.Fatal(err)
	}
	filter1 := ebiten.FilterNearest
	// 把Image文件轉(zhuǎn)成ebiten.Image文件，用于展示
	eImg1, _ := ebiten.NewImageFromImage(img1,filter1)

	var groundX int = 0;
	var groundY int = 437;
	for i :=1;i<5;i++ {
		op1 := &ebiten.DrawImageOptions{}
		op1.GeoM.Translate(float64(groundX), float64(groundY))   // 圖像坐標
		groundX+=250
		// 在屏幕上展示出圖片
		screen.DrawImage(eImg1, op1)

	}

func (g *Game) DrawReady(screen *ebiten.Image)  {
	g.DrawBegin(screen)

	imageObject1, _, _ := ebitenutil.NewImageFromFile("imgs/title.png",ebiten.FilterDefault)
	imageObject2, _, _ := ebitenutil.NewImageFromFile("imgs/start.png",ebiten.FilterDefault)

	gameReady := &GameReady{
		imgReady1: imageObject1,
		img1X: 370,
		img1Y: 140,
		imgReady2: imageObject2,
		img2X: 333,
		img2Y: 200,
	}

	op := &ebiten.DrawImageOptions{}
	op.GeoM.Translate(float64(gameReady.img1X),float64(gameReady.img1Y))
	screen.DrawImage(gameReady.imgReady1,op)

	op.GeoM.Reset()
	op.GeoM.Translate(float64(gameReady.img2X),float64(gameReady.img2Y))
	screen.DrawImage(gameReady.imgReady2,op)

	if ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) {
		x,y := ebiten.CursorPosition()
		rect := image.Rect(gameReady.img2X,gameReady.img2Y,gameReady.img2X+200,gameReady.img2Y+30)
		if (x >=rect.Min.X && x<=rect.Max.X && y>=rect.Min.Y && y<= rect.Max.Y ){
			gameState = 1
		}
	}

}

f, err := os.Open(g.Bird)
	if err != nil {
		log.Fatal(err)
	}
	img, err := png.Decode(f)
	if err != nil {
		log.Fatal(err)
	}
	filter := ebiten.FilterNearest

	// 把Image文件轉(zhuǎn)成ebiten.Image文件，用于展示
	eImg, _ := ebiten.NewImageFromImage(img,filter)

	op := &ebiten.DrawImageOptions{}
	op.GeoM.Translate(g.LocationX,g.LocationY)

	// 在屏幕上展示出圖片
	screen.DrawImage(eImg, op)

//  按空格 跳躍
	if ebiten.IsKeyPressed(ebiten.KeySpace) && g.BirdState != 0 && !isSpace && gameState == 1 &&!isstop {
		isSpace = true
		locationTemp = -5
		g.Bird = "imgs/up.png"
	}

	//  松開空格
	if !ebiten.IsKeyPressed(ebiten.KeySpace) && gameState == 1{
		locationTemp = 2
		g.Bird = "imgs/down.png"
		isSpace = false
	}

	//  判斷是否暫停，然后判斷 小鳥此時 能否移動
	if !isstop { // 暫停
		g.LocationY = g.LocationY + float64(locationTemp)
	}

	// 碰到下邊界  和  上邊界
	if (g.LocationY >= 409 || g.LocationY <= -4 ){
		g.Bird = "imgs/die.png"
		g.BirdState = 0
	}
	//  死亡不讓超出下邊界
	if (g.LocationY >= 479){
		g.LocationY = 479;
	}

	//  小鳥死亡
	if (g.BirdState == 0){
		g.Bird = "imgs/die.png"
		g.LocationY +=3
		locationTemp = 3
	}

var obstacles []*NewBarrier // 切片存數(shù)組
// 下方障礙物
func (o *NewBarrier) DrawTop(screen *ebiten.Image) {
	for i := 1 ;i<o.TopLength;i++{
		op := &ebiten.DrawImageOptions{}
		op.GeoM.Translate(float64(o.X),float64(o.TopY+(i-1)*20))
		screen.DrawImage(o.Image,op)
	}
	op1 := &ebiten.DrawImageOptions{}
	op1.GeoM.Translate(float64(o.X-2),float64(o.TopLength*20-20))
	screen.DrawImage(o.BottomImage,op1)
}

// 上方障礙物
func (o *NewBarrier) DrawBottom(screen *ebiten.Image) {
	for i := 1 ;i<19-o.TopLength;i++{
		op := &ebiten.DrawImageOptions{}
		op.GeoM.Translate(float64(o.X),float64(o.BottomY-(i-1)*20))
		screen.DrawImage(o.Image,op)
	}
	op1 := &ebiten.DrawImageOptions{}
	op1.GeoM.Translate(float64(o.X-2),float64(500-(19-o.TopLength)*20+20))
	screen.DrawImage(o.UpImage,op1)
}

// 中間障礙物
func (o *NewBarrier) DrawMid(screen *ebiten.Image) {
	//fmt.Println(o.HoverUPY,o.TopLength,o.HoverBottomY)
	for i := 1 ;i<o.TopLength;i++{
		op := &ebiten.DrawImageOptions{}
		op.GeoM.Translate(float64(o.X),float64(o.HoverUPY+i*20))
		screen.DrawImage(o.Image,op)
	}
	op1 := &ebiten.DrawImageOptions{}
	op1.GeoM.Translate(float64(o.X-2),float64(o.HoverBottomY))
	screen.DrawImage(o.BottomImage,op1)
	op2 := &ebiten.DrawImageOptions{}
	op2.GeoM.Translate(float64(o.X-2),float64(o.HoverUPY))
	screen.DrawImage(o.UpImage,op2)
}

//  繪制障礙物
func (g *Game) DrawBarrier(screen *ebiten.Image){
	if (gameState != 0){
		for _, o := range obstacles {
			if (o.BarrierStates ==0 || o.BarrierStates==1){
				o.DrawTop(screen)
				o.DrawBottom(screen)
			}else{
				o.DrawMid(screen)
			}
			if (o.X<200){
				if (!o.isScore){
					o.isScore = true
					Score++
				}
			}
		}
	}
}

// 讓障礙物移動起來
func obojsaasdf(obs []*NewBarrier){
	for i:=0;i< len(obs);i++ {
		obs[i].X --
	}
}

func deal()  {
	if len(obstacles) > 0 {
		rand.Seed(time.Now().UnixNano())
		for i := 0; i < len(obstacles); i++{
			if obstacles[i].X < -50 {
				obstacles[i].TopLength = util.Random(15,2)
				// 移除超出屏幕的障礙物
				del := obstacles[0]
				del.X = obstacles[len(obstacles)-1].X+180
				ran := util.Random(15,2)
				ran1 := util.Random(180,80)
				del.TopLength = ran
				del.HoverUPY = ran1
				del.HoverBottomY = ran1 + 20*ran
				del.BarrierStates = util.Random(3,0)
				del.isScore = false
				obstacles = append(obstacles[:i], obstacles[i+1:]...)
				// 添加新的障礙物到切片末尾
				obstacles = append(obstacles, del)
			}
		}
	}
}

// 碰撞檢測
func IsColliding(birdX, birdY float64, birdWidth, birdHeight float64, barrierX, barrierTopY, barrierBottomY float64, barrierWidth int,HoverUp float64,HoverBottom float64) bool {
	birdLeft := birdX
	birdTop := birdY
	birdRight := birdLeft + birdWidth
	birdBottom := birdTop + birdHeight

	barrierLeft := barrierX
	barrierTop := barrierTopY
	barrierRight := barrierLeft + float64(barrierWidth)
	barrierBottom := barrierBottomY

	if birdRight < barrierLeft || birdLeft > barrierRight || ((birdBottom < barrierBottom) && (birdTop > barrierTop)) || ((birdBottom < HoverUp) || (birdTop > HoverBottom+20)) {
		// 沒有碰撞
		return false
	}

	// 有碰撞
	return true
}

func (g *Game) DrawBarrier(screen *ebiten.Image){
	if (gameState != 0){
		for _, o := range obstacles {
			if (o.X<200){
				if (!o.isScore){
					o.isScore = true
					Score++
				}
			}
		}
	}
}
func (g *Game) DrawScore(screen *ebiten.Image) {
	ebitenutil.DebugPrintAt(screen , Itoa(Score),100,100)
}

var isstop bool = false // 游戲是否暫停
//  判斷游戲是否暫停
	if ebiten.IsKeyPressed(ebiten.KeyS) && isPressStop && gameState ==1 && g.BirdState != 0{
		isPressStop = false
		if (!isstop){
			isstop = true
		}else {
			isstop = false
		}
	}
//  判斷是否暫停，然后判斷 小鳥此時 能否移動
	if !isstop { // 暫停
		g.LocationY = g.LocationY + float64(locationTemp)
	}
	// 判斷游戲是否暫停
	if ((g.LocationY != 482 || g.BirdState !=0) && !isstop && gameState != 0){ // 沒有暫停
		obojsaasdf(obstacles)
	}else if  ((g.LocationY != 482 || g.BirdState != 0 ) && isstop) { // 游戲暫停
			//fmt.Println("暫停了 ，障礙物不能動了")
	}

// 繪制 GameOver方法
func (g *Game) DrawGameOver(screen *ebiten.Image) {
	ebitenutil.DebugPrintAt(screen , "GameOver",400,210)
	ebitenutil.DebugPrintAt(screen , Itoa(Score),422,240)
}

// 繪制成績
func (g *Game) DrawScore(screen *ebiten.Image) {
	ebitenutil.DebugPrintAt(screen , Itoa(Score),100,100)
}

// 判斷游戲是否結(jié)束
	if ((g.LocationY != 482 || g.BirdState !=0) && !isstop && gameState != 0){ // 沒有結(jié)束
		obojsaasdf(obstacles)
	}else if  ((g.LocationY != 482 || g.BirdState != 0 ) && isstop) { // 游戲暫停
			//fmt.Println("暫停了 ，障礙物不能動了")
	}else if(g.LocationY == 482 || g.BirdState == 0 ) {  // 游戲結(jié)束
		gameState = 2
		g.DrawBegin(screen)
		g.DrawGameOver(screen)
	}

// 此時游戲結(jié)束 考慮是否重開
	if (gameState == 2){
		if ebiten.IsKeyPressed(ebiten.KeySpace) {   // 按壓空格后 重開
			Score = 0
			gameState = 1
			g.BirdState = 1
			g.LocationY = 200
			obstacles = obstacles[:0] // 清空 原來切片中的障礙物
			makeBarrier()
		}
	}