Александр Фролов

const gulp = require('gulp');             
const sass = require('gulp-sass');        
const concat = require('gulp-concat')
const autoprefixer = require('gulp-autoprefixer');
const cleanCSS = require('gulp-clean-css');
const browserSync = require('browser-sync').create();
const sourcemaps = require('gulp-sourcemaps');
const gcmq = require('gulp-group-css-media-queries');

const config = {
    src: './src',
    css: {
        watch: '/precss/**/*.sass',                     
        src: '/precss/main.sass',
        dest: '/css'                                        
    },
    html: {
        src: '/*.html'
    }
};

gulp.task('build', function () {
    return gulp.src(config.src + config.css.src)
            .pipe(sourcemaps.init())
            .pipe(sass().on('error', sass.logError))
            .pipe(gcmq())
            .pipe(autoprefixer({    
                overrideBrowserslist:  ['> 0.01%'],
                cascade: false
            }))
            // .pipe(cleanCSS({
            //     level: 2
            // }))
            .pipe(sourcemaps.write('.'))
            .pipe(gulp.dest(config.src + config.css.dest))
            .pipe(browserSync.reload({
                stream: true
            }));
});

gulp.task('watch', function () {
    gulp.watch(config.src + config.css.watch, gulp.parallel('build'));
    gulp.watch(config.src + config.html.src).on('change', browserSync.reload);
});

gulp.task('browserSync', function () {
    browserSync.init({
        server: {
            baseDir: config.src
        }
        // online: true,
        // tunnel: true,
        // logLevel: "debug"
    });
});

gulp.task('dist', function(){
    return gulp.src([
        './src/fonts/**/*.{woff,woff2}',
        './src/img/**',
        './src/js/**',
        './src/*html',
        './src/css/*.css'
    ], {
        base: './src'
    })
    .pipe(gulp.dest('dist'))
});

gulp.task('default', gulp.parallel('watch','browserSync', 'build'));