Transform raw data from Toggl to a summarizing information grouping duration hours by task.

TogglCsv.js

const csv = require('csv-parser');
const fs = require('fs');
const createCsvWriter = require('csv-writer').createObjectCsvWriter;
const csvWriter = createCsvWriter({
    path: 'out.csv',
    header: [
        { id: 'date', title: 'Date' },
        { id: 'project', title: 'Project' },
        { id: 'description', title: 'Description' },
        { id: 'duration', title: 'Hours' },
    ]
});

const data = [];

const addTimes = (startTime, endTime) => {
    var times = [0, 0, 0]
    var max = times.length
    var a = (startTime || '').split(':')
    var b = (endTime || '').split(':')
    // normalize time values
    for (var i = 0; i < max; i++) {
        a[i] = isNaN(parseInt(a[i])) ? 0 : parseInt(a[i])
        b[i] = isNaN(parseInt(b[i])) ? 0 : parseInt(b[i])
    }
    // store time values
    for (var i = 0; i < max; i++) {
        times[i] = a[i] + b[i]
    }
    var hours = times[0]
    var minutes = times[1]
    var seconds = times[2]
    if (seconds >= 60) {
        var m = (seconds / 60) << 0
        minutes += m
        seconds -= 60 * m
    }
    if (minutes >= 60) {
        var h = (minutes / 60) << 0
        hours += h
        minutes -= 60 * h
    }
    return ('0' + hours).slice(-2) + ':' + ('0' + minutes).slice(-2) + ':' + ('0' + seconds).slice(-2)
}

const csvRowExtract = (row) => {
    data.push({
        project: row['Project'],
        description: row['Description'],
        date: row['Start date'],
        duration: row['Duration']
    });
};

const csvReduce = (acc, each) => {
    if (acc[each.project] === undefined) {
        acc[each.project] = [];
    }
    if (acc[each.project][each.description] === undefined) {
        acc[each.project][each.description] = [];
    }
    acc[each.project][each.description].push(each);
    return acc;
}

const eachProject = (acc, each) => {
    if (acc[each.project] === undefined) {
        acc[each.project] = [];
    }
    if (acc[each.project][each.description] === undefined) {
        acc[each.project][each.description] = [];
    }
    acc[each.project][each.description].push(each);
    return acc;
}

fs.createReadStream('data.csv')
    .pipe(csv())
    .on('data', csvRowExtract)
    .on('end', () => {
        console.log('CSV processed');
        const csvData = data.reduce(csvReduce, {});
        const projects = Object.keys(csvData);
        const resultArray = projects.map(project => {
            const projectData = csvData[project];
            const tasks = Object.keys(projectData);
            return tasks.map(task => {
                const taskData = projectData[task];
                const project = taskData[0].project;
                const description = taskData[0].description;
                const date = (taskData.length === 1) ? taskData[0].date : taskData[0].date + ' - ' + taskData[taskData.length - 1].date;
                const duration = taskData.reduce((acc, each) => {
                    return addTimes(acc, each.duration);
                }, '00:00:00');
                return {
                    date,
                    project,
                    description,
                    duration
                }
            });
        });
        const result = resultArray.reduce((acc, each) => {
            each.map(e => {
                acc.push(e);
            })
            return acc;
        }, [])
        csvWriter
            .writeRecords(result)
            .then(() => console.log('CSV written'));
    });