gulpfile.js

// Use Gulp Packages
var gulp          = require('gulp');
var autoprefixer  = require('gulp-autoprefixer');
var plumber       = require('gulp-plumber');
var gutil         = require('gulp-util');
var concat        = require('gulp-concat');
var cleanCSS      = require('gulp-clean-css');
var sass          = require('gulp-sass');
var uglify        = require('gulp-uglify');
var browserSync   = require('browser-sync').create();
var sourcemaps    = require("gulp-sourcemaps");
var fileinclude   = require("gulp-file-include");
var watch         = require("gulp-watch");
var runSequence   = require("run-sequence");

// File Paths
var CSS_PATH      = { src: "src/sass/*.scss", dist: "dist/css/" };
var JS_PATH       = { src: "src/js/*.js", dist: "dist/js/" };
var HTML_PATH     = { src: "src/*.html", dist: "dist" };
var INCLUDES_PATH = "src/includes/**/*.html";
var JS_PLUGINS    = [
                    "node_modules/jquery/dist/jquery.min.js",
                    "node_modules/testingen/test.js"
                  ];

// Error Handling
var gulp_src = gulp.src;
gulp.src = function() {
  return gulp_src.apply(gulp, arguments)
    .pipe(plumber(function(error) {
      // Output an error message
      gutil.log(gutil.colors.red('Error (' + error.plugin + '): ' + error.message));
      // emit the end event, to properly end the task
      this.emit('end');
    })
  );
};

// Styles
gulp.task('styles', function() {
  return gulp.src(CSS_PATH.src)
    .pipe(sass({
      includePaths: ['node_modules']
    }))
    .pipe(autoprefixer('last 2 versions'))
    .pipe(sourcemaps.init())
    .pipe(gulp.dest(CSS_PATH.dist))
    .pipe(cleanCSS())
    .pipe(sourcemaps.write())
    .pipe(concat("main.css", {newLine: ""}))
    .pipe(gulp.dest(CSS_PATH.dist))
    .pipe(browserSync.reload({ stream: true }))
});

//  File Include
gulp.task('fileinclude', function () {
  return gulp.src(HTML_PATH.src, )
    .pipe(fileinclude({
      prefix: '@@',
      basepath: 'src/includes'
    }))
    .pipe(gulp.dest(HTML_PATH.dist))
    .pipe(browserSync.reload({ stream: true }))
});

// Scripts
gulp.task('scripts', function () {
  return gulp.src([].concat(JS_PATH.src, JS_PLUGINS))
    .pipe(uglify())
    .pipe(concat('main.min.js'))
    .pipe(gulp.dest(JS_PATH.dist))
    .pipe(browserSync.reload({ stream: true }))
});

// BrowserSync
gulp.task('browserSync', function() {
  browserSync.init({
    server: {
      baseDir: HTML_PATH.dist
    },
    open: false,
    browser: "Google Chrome",
    notify: true,
    notify: {
        styles: {
            top: 'auto',
            bottom: '0',
            borderRadius: '4px 0 0 0',
            opacity: .9
        }
    },
    snippetOptions: {
      rule: {
        match: /<\/body>/i,
        fn: function (snippet, match) {
          return snippet + match;
        }
      }
    }
  })
})

// Watch task
gulp.task('watch', function() {
  watch(CSS_PATH.src, function () {
    runSequence('styles');
  });
  watch(JS_PATH.src, function () {
    runSequence('scripts');
  });
  watch(INCLUDES_PATH, function () {
    runSequence('fileinclude');
  });
  watch([HTML_PATH.src], function () {
    runSequence('fileinclude');
  });
});

gulp.task('default', ['fileinclude', 'styles', 'scripts', 'browserSync', 'watch' ]);