script.js

var fs = require('fs');
var csv = require('csvtojson');
var jsonexport = require('jsonexport');
var data = fs.readFileSync('data.csv', 'utf8');

// create a new data set
var organisedData = [];

// load the unorganised csv file
csv().fromString(data).then(function(json) {
    // loop through every row
    for (var row in json) {

        // add first item to organisedData
        if (organisedData.length === 0) {
            pushData(json[0]);
        }

        // check if the case the row is referring to is already in our organisedData set.
        var caseExists = false;

        for (var party in organisedData) {
            if (json[row].case_number == organisedData[party].case_number) {
                caseExists = party;
            }
        }

        if (caseExists) {
            // a case already exists, add data to existing case in organisedData
            pushData(json[row], caseExists);
        } else {
            // this is a new case, create a new case in organisedData
            pushData(json[row]);
        }
    }

    // the data is now organised. Let's save it out as a new CSV file
    jsonexport(organisedData, function(err, csv) {
        fs.writeFileSync('organisedData.csv', csv);
    })
});

// this part of the code deals with adding and appending to cases
function pushData(row, partyNumber = null) {
    // finds out the role of a party member
    var role = row.party_role.replace(/ /g, '_').toLowerCase();

    // we have to deal with creating new cases and appened to existing cases differently
    if (partyNumber) {
        // checks to see if someone with the same job exists on this case and appends a relevant number
        if (organisedData[partyNumber][role + '_name']) {
            for (var i = 1; 6 > i; i++) {
                if (!organisedData[partyNumber][role + '_name_' + i]) {
                    role = role + '_' + i;
                    break;
                }
            }
        }

        // adds new member to existing case
        organisedData[partyNumber][role + '_name'] = row.party_name;
        organisedData[partyNumber][role + '_email'] = row.party_email;
        organisedData[partyNumber][role + '_phone'] = row.party_phone;
        organisedData[partyNumber][role + '_firm'] = row.party_firm;
    } else {
        // creates a new case with basic information
        var newCase = {};
        newCase.case_number = row.case_number;
        newCase.court = row.court
        newCase.case_name = row.case_name;

        // and adds the first party member
        newCase[role + '_name'] = row.party_name;
        newCase[role + '_email'] = row.party_email;
        newCase[role + '_phone'] = row.party_phone;
        newCase[role + '_firm'] = row.party_firm;

        // add the new case to the organisedData
        organisedData.push(newCase);
    }
}