Rails helper time_ago_in_words() and distance_of_time_in_words() translated into JavaScript

gistfile1.js

var distance_of_time_in_words, time_ago_in_words;
time_ago_in_words = function(from_time, include_seconds) {
    if (include_seconds != null) {
    include_seconds;
  } else {
    include_seconds = false;
  };
  return App.distance_of_time_in_words(from_time, Date.now(), include_seconds);
};
distance_of_time_in_words = function(from_time, to_time, include_seconds) {
  var distance_in_minutes, distance_in_seconds, distance_in_years, minute_offset_for_leap_year, remainder;
    if (include_seconds != null) {
    include_seconds;
  } else {
    include_seconds = false;
  };
    if (to_time != null) {
    to_time;
  } else {
    to_time = 0;
  };
  distance_in_minutes = Math.round(Math.abs(to_time - from_time) / 60 / 1000);
  distance_in_seconds = Math.round(Math.abs(to_time - from_time) / 1000);
  if (0 <= distance_in_minutes && distance_in_minutes <= 1) {
    if (!include_seconds) {
      if (distance_in_minutes === 0) {
        return "less than 1 minute ago";
      } else {
        return "" + distance_in_minutes + " minutes ago";
      }
    }
    if (0 <= distance_in_seconds && distance_in_seconds <= 4) {
      return "less than 5 seconds ago";
    } else if (5 <= distance_in_seconds && distance_in_seconds <= 9) {
      return "less than 10 seconds ago";
    } else if (10 <= distance_in_seconds && distance_in_seconds <= 19) {
      return "less than 20 seconds ago";
    } else if (20 <= distance_in_seconds && distance_in_seconds <= 39) {
      return "less than half a minute ago";
    } else if (40 <= distance_in_seconds && distance_in_seconds <= 59) {
      return "less than 1 minute ago";
    } else {
      return "1 minute ago";
    }
  } else if (2 <= distance_in_minutes && distance_in_minutes <= 44) {
    return "" + distance_in_minutes + " minutes ago";
  } else if (45 <= distance_in_minutes && distance_in_minutes <= 89) {
    return "about 1 hour ago";
  } else if (90 <= distance_in_minutes && distance_in_minutes <= 1439) {
    return "about " + (Math.round(distance_in_minutes / 60.0)) + " hours ago";
  } else if (1440 <= distance_in_minutes && distance_in_minutes <= 2529) {
    return "1 day ago";
  } else if (2530 <= distance_in_minutes && distance_in_minutes <= 43199) {
    return "" + (Math.round(distance_in_minutes / 1440.0)) + " days ago";
  } else if (43200 <= distance_in_minutes && distance_in_minutes <= 86399) {
    return "about 1 month ago";
  } else if (86400 <= distance_in_minutes && distance_in_minutes <= 525599) {
    return "" + (Math.round(distance_in_minutes / 43200.0)) + " months ago";
  } else {
    distance_in_years = distance_in_minutes / 525600;
    minute_offset_for_leap_year = (distance_in_years / 4) * 1440;
    remainder = (distance_in_minutes - minute_offset_for_leap_year) % 525600;
    if (remainder < 131400) {
      return "about " + (Math.round(distance_in_years)) + " years ago";
    } else if (remainder < 394200) {
      return "over " + (Math.round(distance_in_years)) + " years ago";
    } else {
      return "almost " + (Math.round(distance_in_years + 1)) + " years ago";
    }
  }
};