gulpfile.js

var gulp = require('gulp'),

// css
sass = require('gulp-sass'),
autoprefixer = require('gulp-autoprefixer'),
minifycss = require('gulp-minify-css'),

// js
concat = require('gulp-concat'),
uglify = require('gulp-uglify'),

rename = require('gulp-rename'),
copy = require('gulp-copy'),
del = require('del'),

// server
connect = require('gulp-connect'),
url = require('url'),
path = require('path'),
fs = require('fs');


// compile scss
gulp.task('scss', function(){

	gulp.src('src/scss/*.scss')
	.pipe(sass())
	.pipe(autoprefixer({
		browsers: ['last 2 versions', 'Android >= 4.0'],
		cascade: true,
	}))
	.pipe(gulp.dest('dist/css'))
	.pipe(minifycss())
	.pipe(rename({suffix: '.min'}))
	.pipe(gulp.dest('dist/css'));

});

// compile javascript
gulp.task('script', function(){

	gulp.src([
		'src/js/hammer.js', 
		'src/js/jquery.hammer.js',
		'src/js/pinchzoom.js', 
		'src/js/preview-image.js'
		])
	.pipe(concat('preview-image.js'))
	.pipe(gulp.dest('dist/js'))
	.pipe(uglify())
	.pipe(rename({suffix: '.min'}))
	.pipe(gulp.dest('dist/js'));

});

// copy html
gulp.task('html', function(){

	gulp.src('*.html')
	.pipe(copy('dist'))

});

// serve
gulp.task('connect', function(){

	connect.server({
		port: 8888,
		livereload: true		
	});

});

// livereload
gulp.task('livereload', function() {
	gulp.src('*.html')
	.pipe(connect.reload());
});

// build
gulp.task('serve', ['connect'], function(){

	gulp.watch('*.html', ['livereload']);

});

// clean
gulp.task('clean', function(){

	return del(['dist/**']);

});

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

	gulp.start('scss', 'script');

});

// default
gulp.task('default', function(){

	// watch scss files
	gulp.watch('src/scss/*.scss', ['scss']);

	// watch javascript files
	gulp.watch('src/js/**/*.js', ['script']);

});