images.js

const sharp = require('sharp');
const path = require("path");
const fs = require("fs");
let files = [];
let filesToRemove = [];
const scriptArgs = process.argv.slice(2);
const command = scriptArgs[0];

switch (command) {
  case 'clean':
    clean();
    break;
  case 'generate':
    generate();
    break;
  default:
    console.log(`Command is missing.`);
    process.exit(1);
}

async function clean() {
  await findGeneratedImages('pages');
  filesToRemove.forEach(file => {
    fs.unlinkSync(file)
  });
}

async function generate() {
  await findImages('public');
  files.forEach(file => {
    resizeImages(file);
  });
}

async function findGeneratedImages(directory) {
  fs.readdirSync(directory).forEach(file => {
    const absolutePath = path.join(directory, file);
    if (fs.statSync(absolutePath).isDirectory()) return findGeneratedImages(absolutePath);
    else if ((absolutePath.includes('.webp') || absolutePath.includes('-mobile.'))) return filesToRemove.push(absolutePath);
    else return;
  });
}

function findImages(directory) {
  fs.readdirSync(directory).forEach(file => {
    const absolutePath = path.join(directory, file);
    if (fs.statSync(absolutePath).isDirectory()) return findImages(absolutePath);
    else if ((absolutePath.includes('.jpg') || absolutePath.includes('.png')) && !absolutePath.includes('-mobile.')) return files.push(absolutePath);
    else return;
  });
}

async function resizeImages(file) {
  const image = await sharp(file);
  // const metadata = await image.metadata();
  // if (metadata.width > 800) {

  console.log(`Resizing ${file}`)
  
  image.toFile(file.replace('.jpg', '.webp'), (err) => {
    if (err) console.log(err);
  });

  const resizedImage = image.resize(768);
  
  resizedImage.toFile(file.replace('.jpg', '-mobile.jpg'), (err) => {
    if (err) console.log(err);
  });
  resizedImage.toFile(file.replace('.jpg', '-mobile.webp'), (err) => {
    if (err) console.log(err);
  });
}