function countdown(input_id, input_date) {
  // Format input, valid: YYYY-MM-DD HYH:MM:SS
  var date_array = new Array();
  date_array[0] = input_date.substr(0,4); // Year
  date_array[1] = input_date.substr(5,2) - 1; // Month
  date_array[2] = input_date.substr(8,2); // Day
  date_array[3] = input_date.substr(11,2); // Hour
  date_array[4] = input_date.substr(14,2); // Minute
  date_array[5] = input_date.substr(17,2); // Second

  var now = new Date();
  var date = new Date(date_array[0], date_array[1], date_array[2], date_array[3], date_array[4], date_array[5]);
  
  document.getElementById(input_id).innerHTML = datediff(now, date);
}

function datediff(datestart, datestop) {
  counter  = new Date();
  var output = '';
  
  // Calculate difference between the dates
  counter.setTime(Math.abs(datestart.getTime() - datestop.getTime()));
  calcdiff = counter.getTime();

  if (datestart.getTime() < datestop.getTime()) {
    week = Math.floor(calcdiff / (1000 * 60 * 60 * 24 * 7));
    calcdiff -= week * (1000 * 60 * 60 * 24 * 7);
    
    day = Math.floor(calcdiff / (1000 * 60 * 60 * 24)); 
    calcdiff -= day * (1000 * 60 * 60 * 24);
    
    hour = Math.floor(calcdiff / (1000 * 60 * 60)); 
    calcdiff -= hour * (1000 * 60 * 60);
    
    minute = Math.floor(calcdiff / (1000 * 60)); 
    calcdiff -= minute * (1000 * 60);
    
    second = Math.floor(calcdiff / 1000); 
    calcdiff -= second * 1000;
    
    // Format output
    if (week != null && week != '' && week != 0) {
      output = week + 'w ';
    }
    if (day != null && day != '' && day != 0) {
      output = output + day + 'd ';
    }
    if (hour != null && hour != '' && hour != 0) {
      output = output + hour + 'h ';
    } else {
      output = output + '0h ';
    }
    if (minute != null && minute != '' && minute != 0) {
      output = output + minute + 'm ';
    } else {
      doutput = output + '0m ';
    }
    if (second != null && second != '' && second != 0) {
      output = output + second + 's';
    } else {
      output = output + '0s';
    }
    return output;
  } else {
    return 'Tiden är slut';
  }
}