cli

#!/usr/bin/env node

const path = require('path');
const fs = require('fs');
const glob = require('glob');
const mkdirp = require('mkdirp');
const rimraf = require('rimraf');

const argDir = process.argv[2];
const cwdDir = process.cwd();
const scanDir = path.join(cwdDir, argDir);
const cleanFlag = process.argv.includes('--clean');

const waterfall = (fn, arr, end, ...args) => {
  if (arr.length === 0) {
    if (end) end();
    return;
  }
  const p = arr[0];
  fn(p, ...args.concat([(err) => {
    if (err) {
      console.error(err.message);
      process.exit(1);
    } else waterfall(fn, arr.slice(1), end, ...args);
  }]));
};


const wmkdirp = (paths, cb) => waterfall(mkdirp, paths, cb);

const wmkfile = (files, {cwdDir, argDir}, cb) => waterfall((file, next) => {
  // Workaround to ensure relative works always as expected
  const relPath = path.relative(path.dirname(path.join(cwdDir, file)), path.join(argDir, file)).replace(/\\/gi, '/');
  fs.writeFile(path.join(cwdDir, file), `module.exports = require('./${relPath}');\n`, (err) => {
    next(err);
  });
}, files, cb);

glob('{*.js,**/*.js}', {
  // Restrict scan directory
  cwd: scanDir,
  // Retrieve relative paths
  absolute: false,
  // Ignore files that it being used in local only by its sibling
  ignore: '{*.*.js,**/*.*.js}',
}, (err, files) => {
  // Get all root files
  const rfiles = files
    .filter(file => path.dirname(file) === '.');

  // Get all unique directories and ignore root files
  const rdirs = files
    .map(path.dirname.bind(null))
    .filter((file, index, self) => self.indexOf(file) === index && file !== '.');

  // Remove files when clean flag is detected
  if (cleanFlag) {
    const rimrafFiles = rdirs.concat(rfiles);
    const rimrafPattern = path.join(cwdDir, `{${rimrafFiles.join(',')}}`);
    return rimraf(rimrafPattern, (err) => {
      if (err) {
        console.error(err);
        return process.exit(1);
      }
      process.stderr.write(`${rimrafFiles.length} Files cleaned!\n`);
      return 0;
    });
  }

  // Create directory links
  wmkdirp(rdirs, () => {
    process.stderr.write(`${rdirs.length} Directories linked!\n`);
  });

  // Create file links
  wmkfile(files, {
    argDir,
    cwdDir,
  }, () => {
    process.stderr.write(`${files.length} Files linked!\n`);
  });
});