// Initialize modules

// Importing specific gulp API functions lets us write them below as series() instead of gulp.series()

const { src, dest, watch, series, parallel } = require('gulp');

// Importing all the Gulp-related packages we want to use

const sourcemaps = require('gulp-sourcemaps');

const sass = require('gulp-sass');

const concat = require('gulp-concat');

const uglify = require('gulp-uglify');

const postcss = require('gulp-postcss');

const imagemin = require('gulp-imagemin');

const gulp = require('gulp');

const autoprefixer = require('autoprefixer');

const cssnano = require('cssnano');

var replace = require('gulp-replace');

// File paths

const files = {

scssPath: 'Build/assets/scss/**/*.scss',

jsPath: 'Build/assets/js/**/*.js',

imgSquash: 'Build/assets/images/*'

}

// Sass task: compiles the style.scss file into style.css

function scssTask(){

return src(files.scssPath)

.pipe(sourcemaps.init()) // initialize sourcemaps first

.pipe(sass()) // compile SCSS to CSS

.pipe(postcss([ autoprefixer(), cssnano() ])) // PostCSS plugins

.pipe(sourcemaps.write('.')) // write sourcemaps file in current directory

.pipe(dest('Build/assets/production/css')

); // put final CSS in dist folder

}

// JS task: concatenates and uglifies JS files to script.js

function jsTask(){

return src([

files.jsPath

//,'!' + 'includes/js/jquery.min.js', // to exclude any specific files

])

.pipe(concat('all.js'))

.pipe(uglify())

.pipe(dest('Build/assets/production/js')

);

}

// Optimise Images and output to production folder

function imgSquash() {

return gulp .src("Build/assets/images/*")

.pipe(imagemin())

.pipe(gulp.dest("Build/assets/production/images"));

}

// Watch task: watch images, SCSS and JS files for changes

// If any change, run image optimisation, scss and js tasks simultaneously

function watchTask(){

watch([files.imgSquash, files.scssPath, files.jsPath],

series(

parallel(imgSquash, scssTask, jsTask)

)

);

}

// Export the default Gulp task so it can be run

// Runs the scss and js tasks simultaneously, then watch task

exports.default = series(

parallel(imgSquash, scssTask, jsTask),

watchTask

);