/**
 * webpack config
 * @author: shenzm<zhimin.shen@yoho.cn>
 * @date: 2017/3/21
 */

'use strict';

const os = require('os');
const path = require('path');
const shelljs = require('shelljs');
const _ = require('lodash');
const webpack = require('webpack');
const HappyPack = require('happypack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const scss = require('postcss-scss');
const postcssConfig = require('./postcss.config.js');

const happyThreadPool = HappyPack.ThreadPool({ // eslint-disable-line
    size: os.cpus().length
});

const hbsLoader = {
    loader: 'handlebars-loader',
    options: {
        helperDirs: [
            path.join(__dirname, '../js/common/helpers')
        ],
        partialDirs: [
            path.join(__dirname, '../../doraemon/views/partial')
        ]
    }
};

const cssLoader = (env, type) => {
    let loaders = [{
        loader: 'css-loader',
        options: {
            url: false,
            sourceMap: env === 'dev'
        }
    }];

    if (type === 'css') {
        loaders.push({
            loader: 'postcss-loader',
            options: {
                plugins: postcssConfig.postcssPlugin(env),
                parser: scss
            }
        });
    }

    if (env === 'dev') {
        loaders.unshift({
            loader: 'style-loader'
        });
        return loaders;
    }

    return ExtractTextPlugin.extract({
        fallback: type === 'css' ? 'style-loader' : 'vue-style-loader',
        use: loaders
    });
};

const getEntries = () => {
    const entries = {
        libs: ['yoho-jquery'],
        index: path.join(__dirname, '../scss/index.css'),
        common: path.join(__dirname, '../scss/common.css'),
        feature: path.join(__dirname, '../scss/feature.css')
    };

    // 构建各模块子页面JS。生成规则module.page.js
    shelljs.ls(path.join(__dirname, '../js/**/*.page.js')).forEach((f) => {
        const dir = _.slice(f.split('/'), -2); // [modulename, xx.page.js]

        // Important
        // 生成规则：module.page: './js/module/xx.page.js'
        entries[`${dir[0]}.${dir[1].match(/(.*).page.js/)[1]}`] = path.join(__dirname, `../js/${dir.join('/')}`);
    });

    return entries;
};

module.exports = (env) => {
    return {
        entry: getEntries(),
        output: {
            path: path.join(__dirname, 'bundle'), // absolute path
            filename: '[name].js'
        },
        module: {
            rules: [{
                test: /\.vue$/,
                use: [{
                    loader: 'vue-loader',
                    options: {
                        postcss: {
                            plugins: postcssConfig.postcssPlugin(env),
                            parser: scss
                        },
                        autoprefixer: false,
                        loaders: {
                            css: cssLoader(env, 'vue')
                        }
                    }
                }],
            }, {
                test: /\.js$/,
                exclude: [/node_modules/],
                use: [{
                    loader: 'happypack/loader?id=js'
                }]
            }, {
                test: /\.css$/,
                use: cssLoader(env, 'css')
            }, {
                test: /\.hbs$/,
                use: [{
                    loader: 'happypack/loader?id=hbs'
                }]
            }]
        },
        resolve: {
            modules: [
                path.join(__dirname, '../../node_modules'),
                path.join(__dirname, '../vue'),
                path.join(__dirname, '../hbs'),
                path.join(__dirname, '../scss'),
                path.join(__dirname, '../js')
            ],
            alias: {
                vue: 'vue/dist/vue.common.js'
            }
        },
        stats: {
            children: false
        },
        plugins: [
            new HappyPack({
                id: 'js',
                threadPool: happyThreadPool,
                loaders: ['babel-loader'],
            }),
            new HappyPack({
                id: 'hbs',
                threadPool: happyThreadPool,
                loaders: [hbsLoader]
            }),
            new webpack.optimize.CommonsChunkPlugin({
                name: 'libs',
                filename: 'libs.js'
            }),
            new webpack.ProvidePlugin({
                $: 'yoho-jquery',
                jQuery: 'yoho-jquery',
                'window.jQuery': 'yoho-jquery'
            })
        ]
    };
};