time-to calculator giving wrong answer

Question

So i made a function to determine how long i have to wait until the buss arrives:

function arrival(arrtime){

            //convert to seconds
            function toSeconds(time_str) {
                // Extract hours, minutes and seconds
                var parts = time_str.split(':');
                // compute  and return total seconds
                return (parts[0] * 3600) + (parts[1] * 60) + parts[2];// seconds
            }

            var a = new Date().getHours() + ":" + new Date().getMinutes() + ":" + new Date().getSeconds();//current time

            var difference = toSeconds(arrtime) - toSeconds(a);

            function sformat(s) {
                var fm = [
                        Math.floor(s / 60 / 60 / 24), // DAYS
                        Math.floor(s / 60 / 60) % 24, // HOURS
                        Math.floor(s / 60) % 60, // MINUTES
                        s % 60 // SECONDS
                ];
                return $.map(fm, function(v, i) { return ((v < 10) ? '0' : '') + v; }).join(':');
            }

            if (difference > 0){
                result = sformat(difference);
            } else if (difference < 1 && difference > -20) {
                result = "Chegou!";
            } else if (difference <= -20) {
                result = "Amanhã às " + arrtime;
            }

            return result;
        }
//usage example:
arrival("16:30:00");

but it's giving me the wrong answer.... some calculations must be wrong but for the life of me i can't figure it out!

Answer 1

One issue I have found here is your toSeconds function, instead of adding up all the second it is concatenating the seconds as a String. Given your example (16:30:00) you are returning 57600180000 seconds when you should be returning 57600 + 1800 + 00 = 59400 seconds.

Try this method and see if it gets you closer to a solution post a comment if you have other issues.

function toSeconds(time_str) {
  // Extract hours, minutes and seconds
  var parts = time_str.split(':');

  // compute  and return total seconds
  var hoursAsSeconds = parseInt(parts[0]) * 3600;
  var minAsSeconds = parseInt(parts[1]) * 60;
  var seconds = parseInt(parts[2]);

  return hoursAsSeconds + minAsSeconds + seconds;
}