const path = require('path');
const webpack = require('webpack');
const ProvidePlugin = webpack.ProvidePlugin;
const CopyPlugin = require('copy-webpack-plugin');

const srcPath = path.join(__dirname, 'src');

function externalCss (context, request, callback) {
    if (!/\.css$/.test(request)) {
        return callback();
    }

    const sourceFilename = path.resolve(context, request);
    const relativeSource = path.relative(srcPath, sourceFilename);
    const fileRequest = ['.', relativeSource].join(path.sep);
    return callback(null, `umd ${fileRequest}`);
}

module.exports = function (_, options) {
    return {
        stats: 'minimal',

        entry: {
            index: path.join(__dirname, 'src', 'index.js')
        },

        output: {
            path: path.join(__dirname, 'dist'),
            filename: '[name].js',
            libraryTarget: 'umd'
        },

        devtool: 'source-map',

        externals: [
            'hyperapp',
            externalCss
        ],

        module: {
            rules: [
                {
                    test: /\.jsx?$/,
                    use: [
                        {
                            loader: 'babel-loader',
                            options: {
                                presets: [
                                    ['@babel/preset-env', {
                                        modules: false
                                    }]
                                ],
                                plugins: [
                                    ['@babel/plugin-transform-react-jsx', {
                                        pragma: 'h'
                                    }]
                                ]
                            }
                        }
                    ]
                }
            ]
        },

        plugins: [
            new ProvidePlugin({
                h: ['hyperapp', 'h']
            }),

            new CopyPlugin([
                {
                    from: '**/*.css',
                    to: './',
                    context: 'src'
                }
            ])
        ]
    };
};