Using p5.js how would i add a health gui to this code:

function Enemy(x, y, img) {

this.x = x

this.y = y

this.r = 30

this.img = img

this.xdir = 2

this.grow = function() {

console.log('laser beam hit alien')

}

this.shiftDown = function() {

this.xdir *= -1

this.y += this.r

}

this.move = function(dir) {

this.x = this.x + this.xdir // move x direction

}

this.show = function() {

noStroke()

fill(255, 0, 200, 150)

rectMode(CENTER) // draw rectange via centre

ellipse(this.x, this.y, this.r * 2, this.r + 2)

imageMode(CENTER)

image(img, this.x, this.y)

}

}

// Game state constants

const LOADING = 0;

const MAIN_MENU = 1;

const PLAY = 2;

const GAME_OVER = 3;

let Galaga;

let menuship;

let loadship;

let gameover;

let loadsound;

let menusound;

let gamesound;

let file;

let ship;

let enemyWave = [];

let playerLasers = [];

let playerOneImg;

let playerLeftImg;

let playerRightImg;

let enemyShipImg;

let playerLaserImg;

let stars = [];

let currentState = 2;

function preload() {

Galaga = loadImage('./img/galaga.png');

menuship = loadImage('./img/menuship.jpg');

loadship = loadImage('./img/loading.png');

gameover = loadImage('./img/finish.jpg');

loadsound = loadSound('./sounds/load.mp3');

menusound = loadSound('./sounds/main.mp3');

gamesound = loadSound('./sounds/game.mp3');

file = loadStrings('./data/load.txt')

playerOneImg = loadImage("./img/player.png");

playerLeftImg = loadImage("./img/playerLeft.png");

playerRightImg = loadImage("./img/playerRight.png");

playerLaserImg = loadImage("./img/laserRed.png");

enemyShipImg = loadImage("./img/enemyShip.png");

}

function setup() {

createCanvas(windowWidth, windowHeight);

textSize(20);

ship = new Ship();

let randomAmountOfEnemys = random(0, 5);

for (let i = 0; i < randomAmountOfEnemys; i++) {

let randomHeight = random(10, 100);

let randomWidth = random(0, 300);

enemyWave[i] = new Enemy(i * 90 + 90, randomHeight, enemyShipImg);

}

for (let i = 0; i < 100; i++) {

stars[i] = new Star();

}

}

function draw() {

background(0);

if(currentState == 0){

drawLoadingScreen();

}

if(currentState == 1){

drawMainMenuScreen();

}

if(currentState == 2){

drawPlayScreen();

}

if(currentState == 3){

drawGameOverScreen();

}

}

/*

* Draw the loading screen

*/

function drawLoadingScreen(){

background(0);

image(loadship, 600, 300);

loadship.resize(800, 400);

loadsound.setVolume(0.02);

loadsound.play();

}

/*

* Draw the main menu screen

*/

function drawMainMenuScreen(){

background(0);

image(Galaga, 600, 300);

Galaga.resize(700, 300);

image(menuship, 200, 100);

text('Click to begin', 600, 60);

textSize(32);

fill(255, 255, 62);

text('Click to begin', 200, 600);

menusound.setVolume(0.02);

menusound.play();

}

function drawPlayScreen(){

background(0);

ship.show(playerOneImg);

ship.move();

for (let i = 0; i < stars.length; i++) {

stars[i].show();

stars[i].move();

}

for (let i = 0; i < playerLasers.length; i++) {

playerLasers[i].show();

playerLasers[i].move();

for (let j = 0; j < enemyWave.length; j++) {

if (playerLasers[i].hits(enemyWave[j])) {

enemyWave[j].grow();

playerLasers[i].evaporate();

enemyWave.splice(0, 1);

console.log('length of enemyWave ' + enemyWave.length);

}

}

}

let edge = false;

for (let i = 0; i < enemyWave.length; i++) {

enemyWave[i].show();

enemyWave[i].move();

if (enemyWave[i].x > width || enemyWave[i].x < 0) {

edge = true;

}

}

if (edge) {

for (let i = 0; i < enemyWave.length; i++) {

enemyWave[i].shiftDown();

}

}

for (let i = playerLasers.length - 1; i >= 0; i--) {

if (playerLasers[i].toDelete) {

playerLasers.splice(i, 1);

}

}

}

function keyReleased() {

if (key != ' ') {

ship.setDir(0);

}

}

function keyPressed() {

if (key === ' ') {

let playerLaser = new PlayerLaser(ship.x, height - 150, playerLaserImg)

playerLasers.push(playerLaser);

}

if (keyCode === RIGHT_ARROW) {

console.log('moving right');

ship.show(playerRightImg);

ship.setDir(1);

} else if (keyCode === LEFT_ARROW) {

console.log('moving left');

ship.show(playerLeftImg);

ship.setDir(-1);

}

}

function drawGameOverScreen() {

background(0);

gamesound.setVolume(0.1);

gamesound.loop();

image(gameover, 500, 300);

gameover.resize(800, 400);

}

function mouseClicked(){

if (currentState == 0){

currentState = 1;

} else if (currentState == 1){

currentState = 2;

} else if (currentState == 2) {

currentState == 3;

}

}