Create script.js

script.js

@@ -0,0 +1,93 @@
+const playBoard = document.querySelector(".play-board");
+const scoreElement = document.querySelector(".score");
+const highScoreElement = document.querySelector(".high-score");
+const controls = document.querySelectorAll(".controls i");
+
+let gameOver = false;
+let foodX, foodY;
+let snakeX = 5, snakeY = 5;
+let velocityX = 0, velocityY = 0;
+let snakeBody = [];
+let setIntervalId;
+let score = 0;
+
+// Getting high score from the local storage
+let highScore = localStorage.getItem("high-score") || 0;
+highScoreElement.innerText = `High Score: ${highScore}`;
+
+const updateFoodPosition = () => {
+    // Passing a random 1 - 30 value as food position
+    foodX = Math.floor(Math.random() * 30) + 1;
+    foodY = Math.floor(Math.random() * 30) + 1;
+}
+
+const handleGameOver = () => {
+    // Clearing the timer and reloading the page on game over
+    clearInterval(setIntervalId);
+    alert("Game Over! Press OK to replay...");
+    location.reload();
+}
+
+const changeDirection = e => {
+    // Changing velocity value based on key press
+    if(e.key === "ArrowUp" && velocityY != 1) {
+        velocityX = 0;
+        velocityY = -1;
+    } else if(e.key === "ArrowDown" && velocityY != -1) {
+        velocityX = 0;
+        velocityY = 1;
+    } else if(e.key === "ArrowLeft" && velocityX != 1) {
+        velocityX = -1;
+        velocityY = 0;
+    } else if(e.key === "ArrowRight" && velocityX != -1) {
+        velocityX = 1;
+        velocityY = 0;
+    }
+}
+
+// Calling changeDirection on each key click and passing key dataset value as an object
+controls.forEach(button => button.addEventListener("click", () => changeDirection({ key: button.dataset.key })));
+
+const initGame = () => {
+    if(gameOver) return handleGameOver();
+    let html = `<div class="food" style="grid-area: ${foodY} / ${foodX}"></div>`;
+
+    // Checking if the snake hit the food
+    if(snakeX === foodX && snakeY === foodY) {
+        updateFoodPosition();
+        snakeBody.push([foodY, foodX]); // Pushing food position to snake body array
+        score++; // increment score by 1
+        highScore = score >= highScore ? score : highScore;
+        localStorage.setItem("high-score", highScore);
+        scoreElement.innerText = `Score: ${score}`;
+        highScoreElement.innerText = `High Score: ${highScore}`;
+    }
+    // Updating the snake's head position based on the current velocity
+    snakeX += velocityX;
+    snakeY += velocityY;
+    
+    // Shifting forward the values of the elements in the snake body by one
+    for (let i = snakeBody.length - 1; i > 0; i--) {
+        snakeBody[i] = snakeBody[i - 1];
+    }
+    snakeBody[0] = [snakeX, snakeY]; // Setting first element of snake body to current snake position
+
+    // Checking if the snake's head is out of wall, if so setting gameOver to true
+    if(snakeX <= 0 || snakeX > 30 || snakeY <= 0 || snakeY > 30) {
+        return gameOver = true;
+    }
+
+    for (let i = 0; i < snakeBody.length; i++) {
+        // Adding a div for each part of the snake's body
+        html += `<div class="head" style="grid-area: ${snakeBody[i][1]} / ${snakeBody[i][0]}"></div>`;
+        // Checking if the snake head hit the body, if so set gameOver to true
+        if (i !== 0 && snakeBody[0][1] === snakeBody[i][1] && snakeBody[0][0] === snakeBody[i][0]) {
+            gameOver = true;
+        }
+    }
+    playBoard.innerHTML = html;
+}
+
+updateFoodPosition();
+setIntervalId = setInterval(initGame, 100);
+document.addEventListener("keyup", changeDirection);