const path = require('path');

const webpack = require('webpack');  
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CopywebpackPlugin = require('copy-webpack-plugin');  

// Cesium的源码位置
const cesiumSource = 'node_modules/cesium/Source';  
const cesiumWorkers = '../Build/Cesium/Workers';  

module.exports = {  
    context: __dirname,
    entry: {
        app: './src/index.js'
    },
    output: {
        filename: '[name].js',
        path: path.resolve(__dirname, 'dist'),

        // 需要编译Cesium中的多行字符串
        sourcePrefix: ''
    },
    amd: {
        // 让webpack支持Cesium中的require
        toUrlUndefined: true
    },
    node: {
        // 用fs解析node模块
        fs: 'empty'
    },
	resolve: {
        alias: {
            // Cesium module name
            cesium: path.resolve(__dirname, cesiumSource)
        }
    },
    module: {
        rules: [{
            test: /\.css$/,
            use: [ 'style-loader', 'css-loader' ]
        }, {
            test: /\.(png|gif|jpg|jpeg|svg|xml|json)$/,
            use: [ 'url-loader' ]
        }]
    },
	devServer: {  
		contentBase: path.join(__dirname, "dist")
	},
	//调试时显示源码位置
	devtool: `eval`,
    plugins: [
        new HtmlWebpackPlugin({
            template: 'src/index.html'
        }),
        // Copy Cesium Assets, Widgets, and Workers to a static directory
        new CopywebpackPlugin([ { from: path.join(cesiumSource, cesiumWorkers), to: 'Workers' } ]),
        new CopywebpackPlugin([ { from: path.join(cesiumSource, 'Assets'), to: 'Assets' } ]),
        new CopywebpackPlugin([ { from: path.join(cesiumSource, 'Widgets'), to: 'Widgets' } ]),
        new webpack.DefinePlugin({
            // Define relative base path in cesium for loading assets
            CESIUM_BASE_URL: JSON.stringify('')
        }),
		// Split cesium into a seperate bundle
        new webpack.optimize.CommonsChunkPlugin({
            name: 'cesium',
            minChunks: function (module) {
                return module.context && module.context.indexOf('cesium') !== -1;
            }
        })
    ],
};