game.js

import {
    SNAKE_SPEED,
    update as updateSnake, draw as drawSnake, getSnakeHead, snakeIntersection
} from "./snake.js";
import { update as updateFood, draw as drawFood } from "./food.js";
import { outsideGrid } from './grid.js'

let lastRenderTime = 0;
let gameOver = false;
const gameBoard = document.getElementById("game-board")

function main(currentTime) {
    if (gameOver) {
        if (confirm("You lose! Press Ok to restart.")) {
            window.location = "/"
        }
        return;
    }
    window.requestAnimationFrame(main)
    const secondsSinceLastRender = (currentTime - lastRenderTime) / 1000

    if (secondsSinceLastRender < 1 / SNAKE_SPEED) return;
    lastRenderTime = currentTime;

    update();
    draw();
}

window.requestAnimationFrame(main);

function update() {
    updateSnake();
    updateFood();
    checkDeath();
}

function draw() {
    gameBoard.innerHTML = ''
    drawSnake(gameBoard);
    drawFood(gameBoard);
}

function checkDeath() {
    gameOver = outsideGrid(getSnakeHead()) || snakeIntersection()
}