Calculate hours worked

Question

I have the standard hours that the employee hits point. Ex:

8:00 - 12:00 - 13:00 - 18:00

And I have the time that he clocked in that day. Ex:

8 - 12:06 - 12:59 - 17:0

I need to calculate how many hours and minutes were left or added that day.

Answer 1

You can create a function to do the Parsing of each of the time strings, and then calculate the amount of minutes between them:

function parse(horario) {
    // divide a string em duas partes, separado por dois-pontos, e transforma em número
    let [hora, minuto] = horario.split(':').map(v => parseInt(v));
    if (!minuto) { // para o caso de não ter os minutos
        minuto = 0;
    }
    return minuto + (hora * 60);
}

// calcula a duração total em minutos
function duracao(entrada1, saida1, entrada2, saida2) {
    return (parse(saida1) - parse(entrada1)) + (parse(saida2) - parse(entrada2));
}

// duração de uma jornada normal de trabalho (em minutos)
let jornadaNormal = duracao('8:00', '12:00', '13:00', '18:00');
// quantidade de minutos efetivamente trabalhados
let jornada = duracao('8', '12:06', '12:59', '17:00');
// diferença entre as jornadas
let diff = Math.abs(jornada - jornadaNormal);
if (diff != 0) {
    let horas = Math.floor(diff / 60);
    let minutos = diff - (horas * 60);
    console.log(`${horas} horas e ${minutos} minutos a ${jornada > jornadaNormal ? 'mais' : 'menos'}`);
}

With this, the code prints the amount of hours and minutes worked, and shows whether it is more (or less) than the normal workday:

0 hours and 53 minutes less

---

Moment js.

Another alternative is to use the Moment js., which has durations support, through Durations. The idea is similar:

function duracaoTotal(entrada1, saida1, entrada2, saida2) {
    let formatos = ['HH:mm', 'HH']; // formato do horário pode ser com ou sem os minutos
    let inicio = moment(entrada1, formatos);
    let fim = moment(saida1, formatos);
    // diferença entre a hora inicial e final
    let diff = moment.duration(fim.diff(inicio));

    inicio = moment(entrada2, formatos);
    fim = moment(saida2, formatos);
    // obter diferença entre a nova hora inicial e final e somar ao valor anterior
    diff.add(moment.duration(fim.diff(inicio)));

    return diff;
}

// duração de uma jornada normal de trabalho
let jornadaNormal = duracaoTotal('8:00', '12:00', '13:00', '18:00');
// duração efetivamente trabalhada
let jornada = duracaoTotal('8', '12:06', '12:59', '17:00');

// diferença entre as jornadas
let diff = jornada.subtract(jornadaNormal);
if (diff.asMinutes() != 0) {
    // imprimir a quantidade de horas e minutos
    console.log(`${Math.abs(diff.hours())} horas e ${Math.abs(diff.minutes())} minutos a ${diff.asMinutes() > 0 ? 'mais' : 'menos'}`);
}

<script src="https://momentjs.com/downloads/moment.min.js"></script>

---

Remember that both codes above assume that all times refer to the same day. If you have times on different days, you should explicitly put the dates in the strings (similar to what was done in the reply from André).

Answer 2

You can calculate the difference of the dates so the result will be in milliseconds

var diff = Math.abs(date1 - date2);

After this just create a Date object for this.

For example:

var diff = Math.abs(DataInicial - DataFinal);

After that you can put in the new Date that should work.

Answer 3

A very good library for handling dates is Moment.js

For example

    const first = moment('03/05/2019 08:00', 'DD/MM/YYYY HH:SS');
    const second = moment('03/05/2019 12:00', 'DD/MM/YYYY HH:SS');

    second.diff(first, 'hour'); // 4
    second.diff(first, 'minute') // 240