/**
 * Gulp 依赖
 */
var autoprefixer = require('gulp-autoprefixer');
var babelify     = require('babelify');
var browserify   = require('gulp-browserify');
var browser_sync = require('browser-sync').create();
var del          = require('del');
var gulp         = require('gulp');
var jade         = require('gulp-jade');
var minify_css   = require('gulp-minify-css');
var plumber      = require('gulp-plumber');
var reload       = browser_sync.reload;
var rename       = require('gulp-rename');
var sass         = require('gulp-sass');
var sourcemaps   = require('gulp-sourcemaps');
var uglify       = require('gulp-uglify');

/**
 * 路径
 */
var BROWSERIFY_IN    = 'es6/[^_]*.js';
var BROWSERIFY_OUT   = 'dist/static/coin/js';
var BROWSERIFY_WATCH = 'es6/*.js';

var IMG_IN           = 'img/**';
var IMG_OUT          = 'dist/static/coin/img';
var IMG_WATCH        = 'img/**';

var JADE_IN          = 'jade/[^_]*.jade';
var JADE_OUT         = 'dist/templates/coin';
var JADE_WATCH       = 'jade/*.jade';

var SCSS_IN          = 'scss/app.scss';
var SCSS_OUT         = 'dist/static/coin/css';
var SCSS_WATCH       = 'scss/*.scss';

var CLEAN_FILES = [
    'dist/static/coin/**',
    'dist/templates/coin/**'
];

/**
 * Jade 预编译
 */
gulp.task('jade', () => {
    var JADE_OPTIONS = {
        pretty: true
    };

    return gulp.src(JADE_IN)
        // 处理错误, 以下同理
        .pipe(plumber())
        .pipe(jade(JADE_OPTIONS))
        .pipe(gulp.dest(JADE_OUT))
        // 刷新浏览器, 以下同理
        .pipe(reload({stream: true}));
});

/**
 * Scss 预编译
 * 入口文件: scss/app.scss
 */
gulp.task('scss', () => {
    var PREFIXER_OPTIONS = [
        'ie_mob >= 10',
        'ios >= 6.1',
        'android >= 2.3'
    ];

    var SCSS_OPTIONS = {
        outputStyle: 'expanded'
    };

    return gulp.src(SCSS_IN)
        .pipe(sourcemaps.init())
        .pipe(sass(SCSS_OPTIONS).on('error', sass.logError))
        .pipe(autoprefixer(PREFIXER_OPTIONS))
        .pipe(gulp.dest(SCSS_OUT))
        // 生成压缩版本
        .pipe(rename({suffix: '.min'}))
        .pipe(minify_css())
        .pipe(sourcemaps.write('.'))
        .pipe(gulp.dest(SCSS_OUT))
        .pipe(reload({stream: true}));
});

/**
 * Babel 预编译 + Browserify 打包
 */
gulp.task('browserify', () => {
    return gulp.src(BROWSERIFY_IN)
        .pipe(plumber())
        .pipe(sourcemaps.init())
        .pipe(browserify({
            transform: [
                babelify.configure({
                    presets: ['es2015']
                })
            ]
        }))
        .pipe(gulp.dest(BROWSERIFY_OUT))
        // 生成压缩版本
        .pipe(rename({suffix: '.min'}))
        .pipe(uglify())
        .pipe(sourcemaps.write('.'))
        .pipe(gulp.dest(BROWSERIFY_OUT))
        .pipe(reload({stream: true}));
});

/**
 * 图片压缩
 * 太慢, 算了, 以后再说吧
 */
gulp.task('imagemin', () => {
    var IMAGE_OPTIONS = {
        optimizationLevel: 3, // between 0 - 7
        progressive: true,
        interlaced: true
    };

    return gulp.src(IMG_IN)
        .pipe(plumber())
        //.pipe(imagemin(IMAGE_OPTIONS))
        .pipe(gulp.dest(IMG_OUT))
        .pipe(reload({stream: true}));
});

/**
 * 项目清理
 * dev 和 dist 都清掉
 */
gulp.task('clean', () => {
    return del(CLEAN_FILES);
});

/**
 * 代码检查
 */
// 老子代码写这么屌, 从来不检查 (#‵′)凸

/**
 * 启动 Browser-Sync 和文件变动监控
 */
gulp.task('watch', () => {
    browser_sync.init({
        proxy: 'localhost:9999'
    });

    gulp.watch(BROWSERIFY_WATCH, ['browserify']);
    gulp.watch(JADE_WATCH, ['jade']);
    gulp.watch(SCSS_WATCH, ['scss']);
    gulp.watch(IMG_WATCH, ['imagemin']);
});

/**
 * 默认 task
 * 启动 watcher 和 browser-sync
*/
gulp.task('default', ['watch'], () => {
    console.log('Winter is coming, and now my watch shall begins...');
});