tui: snake game

26-tui/05-snake-GAME/README.md

@@ -0,0 +1,26 @@
+# Snake GAME
+
+**ANSI escape codes**
+
+- hide cursor   `\033[?25l`
+- show cursor   `\033[?25h`
+- clear         `\033[2J`
+- move cursor   `\033[1;1H`
+
+### Debugging
+
+sending messages to stderr
+
+```go
+fmt.Fprintf(os.Stderr, "snake after: %v\n", g.snake)
+```
+
+send stderr to file
+
+```sh
+go run . 2> demo.txt
+```
+
+## References
+
+[[00] I will teach you how to make games in your terminal 👾](https://www.youtube.com/watch?v=Fyf-Wh4ckDk)

26-tui/05-snake-GAME/game.go

@@ -0,0 +1,199 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"math/rand"
+	"os"
+	"os/signal"
+	"strconv"
+	"time"
+
+	"github.com/mattn/go-tty"
+)
+
+const (
+	snakeSprite = "█"
+	foodSprite  = "◆"
+)
+
+type game struct {
+	score int
+	snake *snake
+	food  position
+	pause bool
+
+	x, y int
+}
+
+func newGame(x, y int) *game {
+	rand.Seed(time.Now().UnixNano())
+
+	game := &game{
+		score: 0,
+		snake: newSnake(x, y),
+		food:  randomPosition(),
+		pause: false,
+		x:     x,
+		y:     y,
+	}
+
+	go game.listenForKeyPress()
+
+	return game
+}
+
+func (g *game) listenForKeyPress() {
+	tty, err := tty.Open()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer tty.Close()
+
+	for {
+		char, err := tty.ReadRune()
+		if err != nil {
+			panic(err)
+		}
+
+		switch char {
+		case 'w':
+			if g.snake.direction != south {
+				g.snake.direction = north
+			}
+
+		case 'a':
+			if g.snake.direction != east {
+				g.snake.direction = west
+			}
+
+		case 's':
+			if g.snake.direction != north {
+				g.snake.direction = south
+			}
+
+		case 'd':
+			if g.snake.direction != west {
+				g.snake.direction = east
+			}
+
+		case ' ':
+			g.pause = g.pause != true
+
+		// up arrow \x1b[A
+		case 'A':
+			increaseSpeed()
+
+		// down arrow \x1b[B
+		case 'B':
+			decreaseSpeed()
+		}
+	}
+}
+
+func (g *game) beforeGame() {
+	hideCursor(screen)
+
+	// handle CTRL C
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, os.Interrupt)
+
+	go func() {
+		for range c {
+			g.over()
+		}
+	}()
+}
+
+func (g *game) over() {
+	g.pause = true
+	time.Sleep(2 * time.Second)
+
+	clear(screen)
+	showCursor(screen)
+
+	moveCursor(screen, 1, 1)
+	draw(screen, "game over. score: "+strconv.Itoa(g.score))
+
+	render()
+
+	os.Exit(0)
+}
+
+func (g *game) placeNewFood() {
+	for {
+		newFoodPosition := randomPosition()
+
+		if sameSpot(newFoodPosition, g.food) {
+			continue
+		}
+
+		for _, pos := range g.snake.body {
+			if sameSpot(newFoodPosition, pos) {
+				continue
+			}
+		}
+
+		g.food = newFoodPosition
+
+		break
+	}
+}
+
+func (g *game) nextStep() {
+	if g.pause {
+		return
+	}
+
+	maxX, maxY := getSize()
+	sLen := len(g.snake.body)
+
+	oldTail := g.snake.body[sLen-1]
+
+	fmt.Fprintf(os.Stderr, "snake before: %v\n", g.snake)
+
+	if g.snake.moveAndEat(g.snake.direction, g.food) {
+		g.score += 1
+
+		moveCursor(screen, g.food.x, g.food.y)
+		draw(screen, snakeSprite)
+
+		g.placeNewFood()
+		moveCursor(screen, g.food.x, g.food.y)
+		draw(screen, foodSprite)
+	} else {
+		moveCursor(screen, oldTail.x, oldTail.y)
+		draw(screen, " ")
+
+		fmt.Fprintf(os.Stderr, "snake else: %v\n", g.snake)
+		moveCursor(screen, g.snake.body[0].x, g.snake.body[0].y)
+		draw(screen, snakeSprite)
+	}
+
+	fmt.Fprintf(os.Stderr, "snake after: %v\n", g.snake)
+
+	if g.snake.hitWall(maxX, maxY) || g.snake.ateItself() {
+		g.over()
+	}
+
+	render()
+}
+
+func (g *game) draw() {
+	maxX, maxY := getSize()
+	g.snake.teleport(maxX, maxY)
+	g.food = teleport(g.x, g.y, maxX, maxY, g.food)
+	g.x = maxX
+	g.y = maxY
+	// food
+	moveCursor(screen, g.food.x, g.food.y)
+	draw(screen, foodSprite)
+
+	// snake
+	for _, pos := range g.snake.body {
+		moveCursor(screen, pos.x, pos.y)
+		draw(screen, snakeSprite)
+	}
+
+	render()
+}

26-tui/05-snake-GAME/go.mod

@@ -0,0 +1,10 @@
+module github.com/pskp-95/snake-game
+
+go 1.25.4
+
+require (
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mattn/go-tty v0.0.7 // indirect
+	golang.org/x/sys v0.41.0 // indirect
+	golang.org/x/term v0.40.0 // indirect
+)

26-tui/05-snake-GAME/go.sum

@@ -0,0 +1,9 @@
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-tty v0.0.7 h1:KJ486B6qI8+wBO7kQxYgmmEFDaFEE96JMBQ7h400N8Q=
+github.com/mattn/go-tty v0.0.7/go.mod h1:f2i5ZOvXBU/tCABmLmOfzLz9azMo5wdAaElRNnJKr+k=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
+golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/term v0.40.0 h1:36e4zGLqU4yhjlmxEaagx2KuYbJq3EwY8K943ZsHcvg=
+golang.org/x/term v0.40.0/go.mod h1:w2P8uVp06p2iyKKuvXIm7N/y0UCRt3UfJTfZ7oOpglM=

26-tui/05-snake-GAME/helper.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"math/rand"
+	"os"
+	"time"
+
+	"golang.org/x/term"
+)
+
+var screen = bufio.NewWriter(os.Stdout)
+var sleepTime time.Duration = 100
+
+func hideCursor(w io.Writer) {
+	fmt.Fprintf(w, "\033[?25l")
+}
+
+func showCursor(w io.Writer) {
+	fmt.Fprintf(w, "\033[?25h")
+}
+
+func moveCursor(w io.Writer, x, y int) {
+	fmt.Fprintf(w, "\033[%d;%dH", y, x)
+}
+
+func clear(w io.Writer) {
+	fmt.Fprintf(w, "\033[2J")
+}
+
+func draw(w io.Writer, str string) {
+	fmt.Fprint(w, str)
+}
+
+func render() {
+	screen.Flush()
+}
+
+func getSize() (int, int) {
+	w, h, err := term.GetSize(int(os.Stdout.Fd()))
+	if err != nil {
+		panic(err)
+	}
+
+	return w, h
+}
+
+func sameSpot(a, b position) bool {
+	return a.x == b.x && a.y == b.y
+}
+
+func randomPosition() position {
+	width, height := getSize()
+	x := rand.Intn(width-2) + 2
+	y := rand.Intn(height-2) + 2
+
+	return position{x: x, y: y}
+}
+
+func drawBox(maxX, maxY int) {
+	for i := 1; i <= maxX; i++ {
+		moveCursor(screen, i, 1)
+		draw(screen, "─")
+
+		moveCursor(screen, i, maxY)
+		draw(screen, "─")
+	}
+
+	for i := 1; i <= maxY; i++ {
+		moveCursor(screen, 1, i)
+		draw(screen, "│")
+
+		moveCursor(screen, maxX, i)
+		draw(screen, "│")
+	}
+	moveCursor(screen, 1, 1)
+	draw(screen, "┌")
+	moveCursor(screen, 1, maxY)
+	draw(screen, "└")
+	moveCursor(screen, maxX, 1)
+	draw(screen, "┐")
+	moveCursor(screen, maxX, maxY)
+	draw(screen, "┘")
+}
+
+func increaseSpeed() {
+	sleepTime -= 10
+	if sleepTime < 30 {
+		sleepTime = 30
+	}
+}
+
+func decreaseSpeed() {
+	sleepTime += 10
+	if sleepTime > 200 {
+		sleepTime = 200
+	}
+}
+
+func teleport(w1, h1, w2, h2 int, pos position) position {
+	np := position{
+		x: 1 + ((pos.x * w2) / w1),
+		y: 1 + ((pos.y * h2) / h1),
+	}
+
+	fmt.Fprintf(os.Stderr, "w1: %d, h1: %d, w2: %d, h2: %d, pos: %v, np: %v\n", w1, h1, w2, h2, pos, np)
+	return np
+}