owncast/build/javascript/node_modules/purgecss/bin/purgecss

#!/usr/bin/env node
const program = require('commander');
const fs = require('fs');
const { default: PurgeCSS, defaultOptions, setOptions } = require('../lib/purgecss')

function getList(list) {
  return list.split(',')
}

async function writeCSSToFile(filePath, css) {
  try {
    await fs.promises.writeFile(filePath, css);
  } catch(err) {
    console.error(err.message);
  }
}

program
  .usage('--css <css> --content <content> [options]')
  .option('-con, --content <files>', 'glob of content files (comma separated)', getList)
  .option('-css, --css <files>', 'glob of css files (comma separated)', getList)
  .option('-c, --config <path>', 'path to the configuration file')
  .option('-o, --output <path>', 'file path directory to write purged css files to')
  .option('-font, --font-face', 'option to remove unused font-faces')
  .option('-keyframes, --keyframes', 'option to remove unused keyframes')
  .option('-rejected, --rejected', 'option to output rejected selectors')
  .option('-w, --whitelist <list>', 'list of classes that should not be removed (comma separated)', getList);

program.parse(process.argv);

// config file is not specified or the content and css are not,
// PurgeCSS will not run
if (!program.config && !(program.content && program.css)) {
  program.help();
}

(async() => {
  // if the config file is present, use it
  // other options specified will override
  let options = defaultOptions;
  if (program.config) {
    options = await setOptions(program.config);
  }
  if (program.content) options.content = program.content;
  if (program.css) options.css = program.css;
  if (program.fontFace) options.fontFace = program.fontFace;
  if (program.keyframes) options.keyframes = program.keyframes;
  if (program.rejected) options.rejected = program.rejected;
  if (program.variables) options.variables = program.variables;
  if (program.whitelist) options.whitelist = program.whitelist;

  // if (!options.css) {
  //   options.css = [{
  //     raw: stdInCSS
  //   }]
  // }

  const purged = await new PurgeCSS().purge(options);

  const output = options.output || program.output;
  // output results in specified directory
  if (output) {
    if (purged.length === 1 && output.endsWith('.css')) {
      await writeCSSToFile(output, purged[0].css)
      return
    }

    for (const purgedResult of purged) {
      const fileName = purgedResult.file.split("/").pop();
      await writeCSSToFile(`${output}/${fileName}`, purgedResult.css);
    }
  } else {
    console.log(JSON.stringify(purged));
  }

})()