Gulpfile.js

'use strict'

const gulp = require('gulp')
const babel = require('gulp-babel')
const sass = require('gulp-sass')
const uglifyCss = require('gulp-uglifycss')
const uglifyJs = require('gulp-uglify')
const concat = require('gulp-concat')
const ts = require('gulp-typescript')
const del = require('del')
const replace = require('gulp-replace')

const libsTs = [
  'node_modules/jquery/src/jquery.js',
  'node_modules/jquery-ui/ui/widget.js',
  'node_modules/jquery.autocomplete/jquery.autocomplete.js',
  'node_modules/lightgallery/src/js/lightgallery.js',
  'node_modules/typed.js/lib/typed.js',
  'public/.ts/app.ts',
]

const libsScss = [
  'node_modules/bootstrap/scss/bootstrap.scss',
  'node_modules/jquery-ui/themes/base/all.css',
  'node_modules/font-awesome/scss/font-awesome.scss',
  'public/.scss/jquery.mThumbnailScroller.css',
  'public/.scss/app.scss',
]

const libAssets = [
  'node_modules/font-awesome/fonts/*',
]

function clean () {
  return del(['public/static/*'])
}

function css () {
  return gulp.src(libsScss).
    pipe(sass()).
    pipe(uglifyCss()).
    pipe(concat('app.css')).
    pipe(replace(/(?<=(src|url)\w*\(\w*("|')).+?(?=("|')\w*\)\w*)/g, (match) => {
      if (!match.startsWith('data')) {
        const parts = match.split('/')
        return '/static/' + parts.pop()
      }
    })).
    pipe(gulp.dest('./public/static/'))
}

function assets () {
  return gulp.src(libAssets).
    pipe(gulp.dest('./public/static/'))
}

function js () {
  return gulp.src(libsTs).
    pipe(ts({ noImplicitAny: false, allowJs: true })).
    pipe(babel()).
    pipe(uglifyJs()).
    pipe(concat('app.js')).
    pipe(gulp.dest('./public/static/'))
}

function watch () {
  gulp.watch(libsScss, js)
  gulp.watch(libsTs, css)
}

const build = gulp.series(clean, gulp.parallel(assets, css, js))

exports.clean = clean
exports.css = css
exports.js = js
exports.watch = watch
exports.build = build
exports.default = build

package.json

{
  "name": "app",
  "description": "app",
  "version": "1.0.0",
  "license": "unlicenced",
  "private": true,
  "dependencies": {
    "@babel/core": "^7.7.5",
    "@types/jquery": "^3.3.31",
    "@types/jqueryui": "^1.12.9",
    "@types/node": "^12.12.20",
    "bootstrap": "^4.4.1",
    "bootswatch": "^4.4.1",
    "core-js": "^3.5.0",
    "cross-env": "^6.0.3",
    "del": "^5.1.0",
    "font-awesome": "^4.7.0",
    "gsap": "^3.0.4",
    "gulp": "^4.0.2",
    "gulp-babel": "^8.0.0",
    "gulp-cli": "^2.2.0",
    "gulp-concat": "^2.6.1",
    "gulp-copy": "^4.0.1",
    "gulp-css": "^0.1.0",
    "gulp-less": "^4.0.1",
    "gulp-replace": "^1.0.0",
    "gulp-sass": "^4.0.2",
    "gulp-typescript": "^5.0.1",
    "gulp-uglify": "^3.0.2",
    "gulp-uglifycss": "^1.1.0",
    "jquery": "^3.4.1",
    "jquery-ui": "^1.12.1",
    "jquery.autocomplete": "^1.2.0",
    "lightgallery": "^1.6.12",
    "node-sass": "^4.13.0",
    "popper.js": "^1.16.0",
    "swiper": "^5.2.1",
    "typed.js": "^2.0.10",
    "typescript": "^3.7.3"
  }
}