text: var startsAsUrl = require('./starts-as-url');
  
  var OptimizationLevel = require('../../../options/optimization-level').OptimizationLevel;
  
  var DOT_ZERO_PATTERN = /(^|\D)\.0+(\D|$)/g;
  var FRACTION_PATTERN = /\.([1-9]*)0+(\D|$)/g;
  var LEADING_ZERO_FRACTION_PATTERN = /(^|\D)0\.(\d)/g;
  var MINUS_ZERO_FRACTION_PATTERN = /([^\w\d\-]|^)\-0([^\.]|$)/g;
  var ZERO_PREFIXED_UNIT_PATTERN = /(^|\s)0+([1-9])/g;
  
  var plugin = {
    level1: {
      value: function fraction(name, value, options) {
        if (!options.level[OptimizationLevel.One].replaceZeroUnits) {
          return value;
        }
  
        if (startsAsUrl(value)) {
          return value;
        }
  
        if (value.indexOf('0') == -1) {
          return value;
        }
  
        if (value.indexOf('-') > -1) {
          value = value
            .replace(MINUS_ZERO_FRACTION_PATTERN, '$10$2')
            .replace(MINUS_ZERO_FRACTION_PATTERN, '$10$2');
        }
  
        return value
          .replace(ZERO_PREFIXED_UNIT_PATTERN, '$1$2')
          .replace(DOT_ZERO_PATTERN, '$10$2')
          .replace(FRACTION_PATTERN, function (match, nonZeroPart, suffix) {
            return (nonZeroPart.length > 0 ? '.' : '') + nonZeroPart + suffix;
          })
          .replace(LEADING_ZERO_FRACTION_PATTERN, '$1.$2');
      }
    }
  };
  
  module.exports = plugin;
  