var path = require('path');
var config = require('../config');
var utils = require('./utils');
var webpack = require('webpack');
var merge = require('webpack-merge');
var baseWebpackConfig = require('./webpack.base.conf');
var ExtractTextPlugin = require('extract-text-webpack-plugin');
var HtmlWebpackPlugin = require('html-webpack-plugin');
var env = process.env.NODE_ENV === 'testing' ? require('../config/test.env') : config.build.env;

var webpackConfig = merge(baseWebpackConfig, {
  module: {
    loaders: utils.styleLoaders({
      extract: true
    })
  },
  output: {
    path: config.build.assetsRoot,
    filename: utils.assetsPath('[name].min.js'),
    chunkFilename: utils.assetsPath('[id].min.js')
  },
  vue: {
    loaders: utils.cssLoaders({
      extract: true
    })
  },
  plugins: [
    // http://vuejs.github.io/vue-loader/workflow/production.html
    new webpack.DefinePlugin({
      'process.env': env
    }),
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false
      }
    }),
    new webpack.optimize.OccurenceOrderPlugin(),
    // extract css into its own file
    new ExtractTextPlugin(utils.assetsPath('[name].min.css')),
    // generate dist index.html with correct asset hash for caching.
    // you can customize output by editing /index.html
    // see https://github.com/ampedandwired/html-webpack-plugin
    new HtmlWebpackPlugin({
      filename: process.env.NODE_ENV === 'testing' ? 'index.html' : config.build.index,
      template: 'index.html',
      inject: true,
      minify: {
        removeComments: true,
        collapseWhitespace: true,
        removeAttributeQuotes: true
        // more options:
        // https://github.com/kangax/html-minifier#options-quick-reference
      },
      // necessary to consistently work with multiple chunks via CommonsChunkPlugin
      chunksSortMode: 'dependency'
    }),
    // split vendor js into its own file
    new webpack.optimize.CommonsChunkPlugin({
      name: 'vendor',
      minChunks: function(module) {
        // any required modules inside node_modules are extracted to vendor
        return (
          module.resource &&
          (/\.js$/).test(module.resource) &&
          module.resource.indexOf(
            path.join(__dirname, '../node_modules')
          ) === 0
        );
      }
    }),
    // extract webpack runtime and module manifest to its own file in order to
    // prevent vendor hash from being updated whenever app bundle is updated
    new webpack.optimize.CommonsChunkPlugin({
      name: 'manifest',
      chunks: ['vendor']
    })
  ]
});

if (config.build.productionGzip) {
  var CompressionWebpackPlugin = require('compression-webpack-plugin');

  webpackConfig.plugins.push(
    new CompressionWebpackPlugin({
      asset: '[path].gz[query]',
      algorithm: 'gzip',
      test: new RegExp(
        '\\.(' +
        config.build.productionGzipExtensions.join('|') +
        ')$'
      ),
      threshold: 10240,
      minRatio: 0.8
    })
  );
}

module.exports = webpackConfig;