gulpfile.js

const gulp=require('gulp');
const browserify=require('browserify');
const rollupify=require('rollupify');
const babelify=require('babelify');
const concat=require('gulp-concat');
const source=require('vinyl-source-stream');
const streamify = require('gulp-streamify');
const uglify = require('gulp-uglify');
const connect=require('gulp-connect');
const imagemin = require('gulp-imagemin');
const cleanCSS = require('gulp-clean-css');
const purify = require('gulp-purifycss');
const htmlmin = require('gulp-htmlmin');
const ghPages = require('gulp-gh-pages');
const del = require('del');
const buffer = require('gulp-buffer');
const rev = require('gulp-rev');
const revRewrite = require('gulp-rev-rewrite');

const cssAssets = [
    `${__dirname}/src/css/materialize.css`,
    `${__dirname}/src/css/animate.css`,
    `${__dirname}/src/css/styles.css`
];

//Common task for dev & prod
gulp.task('clean', function () {
    return del(['dist/**/*']);
});

//Gulp tasks for Development

gulp.task('server',function () {
    connect.server({
        base:'http://localhost',
        port:'8000',
        root:'./dist',
        livereload:true
    });
});
gulp.task('js',function () {
    browserify(`${__dirname}/src/js/script.js`)
        .transform(babelify)
        .bundle()
        .pipe(source('bundle.js'))
        .pipe(gulp.dest(`${__dirname}/dist/js`))
        .pipe(connect.reload());
});
gulp.task('css',function () {
   gulp.src(cssAssets)
       .pipe(concat('bundle.css'))
       .pipe(cleanCSS())
       .pipe(gulp.dest(`${__dirname}/dist/css`))
       .pipe(connect.reload());
});
gulp.task('images',function () {
    gulp.src(`${__dirname}/src/img/*`)
        .pipe(gulp.dest(`${__dirname}/dist/img`))
        .pipe(connect.reload());
});
gulp.task('fonts',function () {
    gulp.src(`${__dirname}/src/fonts/*`)
        .pipe(gulp.dest(`${__dirname}/dist/fonts`))
        .pipe(connect.reload());
});
gulp.task('manifest',function () {
    gulp.src(`${__dirname}/src/manifest.json`)
        .pipe(gulp.dest(`${__dirname}/dist`))
        .pipe(connect.reload());
});
gulp.task('html',function () {
    gulp.src(`${__dirname}/src/index.html`)
        .pipe(gulp.dest(`${__dirname}/dist`))
        .pipe(connect.reload());
});
gulp.task('watch',function () {
    gulp.watch(`${__dirname}/src/index.html`,['html']);
    gulp.watch(`${__dirname}/src/manifest.json`,['manifest']);
    gulp.watch(`${__dirname}/src/css/*`,['css']);
    gulp.watch(`${__dirname}/src/js/*`,['js']);
    gulp.watch(`${__dirname}/src/img/*`,['images']);
});


gulp.task('default',['css','js','images','fonts','html','manifest','server','watch'],function () {
   console.log('Server connected at http://localhost:8000');
   console.log('Watching for changes.');
});

//Gulp task for Optimised Build

gulp.task('build',['clean'], function() {

    browserify(`${__dirname}/src/js/script.js`)
        .transform(rollupify)
        .transform(babelify)
        .bundle()
        .pipe(source('bundle.js'))
        .pipe(streamify(uglify()))
        .pipe(buffer())
        .pipe(gulp.dest(`${__dirname}/build/js`));

    gulp.src(`${__dirname}/src/img/*`)
        .pipe(imagemin([imagemin.optipng({optimizationLevel: 7})]))
        .pipe(gulp.dest(`${__dirname}/build/img`));

    gulp.task('fonts',function () {
        gulp.src(`${__dirname}/src/fonts/*`)
            .pipe(gulp.dest(`${__dirname}/build/fonts`));
    });

    gulp.src(`${__dirname}/src/manifest.json`)
        .pipe(gulp.dest(`${__dirname}/build`));

    gulp.src(`${__dirname}/src/index.html`)
        .pipe(htmlmin({
                collapseWhitespace:true,
                minifyCSS:true,
                minifyJS:true,
                removeComments:true
            })
        )
        .pipe(gulp.dest(`${__dirname}/build`));

    gulp.src(cssAssets)
        .pipe(concat('bundle.css'))
        .pipe(cleanCSS())
        .pipe(gulp.dest(`${__dirname}/build/css`));

    /*
        gulp.src(`${__dirname}/dist/!**!/!*`)
            .pipe(rev())
            .pipe(revDelete())
            .pipe(gulp.dest('dist'))
            .pipe(revRewrite(rev.manifest()))
            .pipe(gulp.dest('dist'));*/
});

//Gulp task for automated deploy
gulp.task('deploy', function() {
    return gulp.src(`${__dirname}/build/**/*`)
        .pipe(ghPages());
});