util.js

'use strict';

var path = require('path'),
    fs = require('fs'),
    rewrite,
    rewriteFile;

rewriteFile = function rewriteFile (args) {
  args.path = args.path || process.cwd();
  var fullPath = path.join(args.path, args.file);

  args.haystack = fs.readFileSync(fullPath, 'utf8');
  var body = rewrite(args);

  fs.writeFileSync(fullPath, body);
};

rewrite = function rewrite (args) {
  var lines = args.haystack.split('\n');

  var otherwiseLineIndex = 0;
  lines.forEach(function (line, i) {
    if (line.indexOf(args.needle) !== -1) {
      otherwiseLineIndex = i;
    }
  });

  var spaceStr = '';

  lines.splice(otherwiseLineIndex, 0, args.splicable.map(function (line) {
    return spaceStr + line;
  }).join('\n'));

  return lines.join('\n');
};

module.exports = {
  rewrite: rewrite,
  rewriteFile: rewriteFile
};