var gulp			  = require('gulp'),
	 sass			  = require('gulp-sass');
	 browserSync  = require('browser-sync'),
	 concat       = require('gulp-concat'),
	 uglify       = require('gulp-uglifyjs'),
	 cssnano      = require('gulp-cssnano'),
	 rename       = require('gulp-rename'),
	 del 			  = require('del'),
	 imagemin     = require('gulp-imagemin'),
	 pngquant     = require('imagemin-pngquant'),
	 cache        = require('gulp-cache'),
	 autoprefixer = require('gulp-autoprefixer');

gulp.task('sass', function() {
	return gulp.src('app/sass/**/*.sass')
	.pipe(sass())
	.pipe(autoprefixer(['last 15 versions', '> 1%', 'ie 8', 'ie 7'], {cascade: true}))
	.pipe(gulp.dest('app/css'))
	.pipe(browserSync.reload({stream: true}))
});

gulp.task('scripts', function(){
	return gulp.src([
		'app/libs/jquery/dist/jquery.min.js',
		'app/libs/magnific-popup/dist/jquery.magnific-popup.min.js',
	])
	.pipe(concat('libs.min.js'))
	.pipe(uglify())
	.pipe(gulp.dest('app/js'));
});

gulp.task('css-libs', ['sass'], function(){
	return gulp.src('app/css/libs.css')
	.pipe(cssnano())
	.pipe(rename({suffix: '.min'}))
	.pipe(gulp.dest('app/css'));
});

gulp.task('browser-sync', function() {
	browserSync({
		server: {
			baseDir: 'app'
		},
		notify: false
	});
});

gulp.task('clean', function(){
	return del.sync('dist');
});

gulp.task('clear', function(){
	return cache.clearAll();
});

gulp.task('img', function() {
	return gulp.src('app/img/**/*')
	.pipe(cache(imagemin({
		interlaced: true,
		progressive: true,
		svgoPlagins: [{removeViewBox: false}],
		une: [pngquant()]
	})))
	.pipe(gulp.dest('dist/img'));
});

gulp.task('watch', ['browser-sync', 'css-libs', 'scripts'], function() {
	gulp.watch('app/sass/**/*.sass', ['sass']);
	gulp.watch('app/*.html', browserSync.reload);
	gulp.watch('app/**/*.js', browserSync.reload);
});

gulp.task('build', ['clean', 'img', 'sass', 'scripts'], function(){
	var buildCss = gulp.src([
		'app/css/main.css',
		'app/css/libs.min.css'
	])
	.pipe(gulp.dest('dist/css'));

	var buildFonts = gulp.src([
		'app/fonts/**/*'
	])
	.pipe(gulp.dest('dist/fonts'));

	var buildJs = gulp.src([
		'app/js/**/*'])
	.pipe(gulp.dest('dist/js'));

	var buildHtml = gulp.src('app/*.html')
	.pipe(gulp.dest('dist'));
});