text: /**
   * The MIT License (MIT)
   *
   * Copyright (c) 2017 Juan Mellado
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  import { createFilter } from 'rollup-pluginutils';
  import { extname } from 'path';
  import postcss from 'postcss';
  
  export default function(options = {}) {
    options.extensions = options.extensions || ['.css'];
  
    // Rollup filter
    let filter = createFilter(options.include, options.exclude);
  
    // Checks supported file extensions and Rollup filter
    function _supports(id) {
      let extension = extname(id);
  
      return (options.extensions.indexOf(extension) !== -1) && filter(id);
    }
  
    // PostCSS options
    function _options(id) {
      return {
        syntax: options.syntax,
        parser: options.parser,
        stringifier: options.stringifier,
        map: {
          inline: false,
          annotation: false,
        },
        from: id,
        to: id,
      };
    }
  
    // Process the CSS with PostCSS
    function _process(code, id) {
      let processor = postcss(options.plugins || []);
      let opts = _options(id);
  
      return Promise.resolve()
        .then(() => processor.process(code, opts))
        .then((result) => {
          return {
            code: `export default ${JSON.stringify(result.css)}`,
            map: { mappings: '' },
          };
        });
    }
  
    // Plugin
    return {
      name: 'rollup-plugin-postcss-shadow',
  
      transform(code, id) {
        return _supports(id) ? _process(code, id) : null;
      },
    };
  }
  