transform.js

const csv = require("csv");
const process = require("process");
const fs = require("fs");
const _ = require("lodash");

const files = {
  source: "Explorer-NDC-Data.csv",
  meta: "Explorer-Nav-And-Legend-Data.csv",
};

const fromCSV = (content) => {
  return new Promise((resolve, reject) => csv.parse(content, {
    columns: (row) => row.map((r) => r.split("\n")[0])
  }, (error, data) => {
    if (error) {
      return reject(error);
    }

    return resolve(data);
  }));
};

const numberedTaggedTitleRxp = /(\d+\.\ )?(.+)(VIS|TXT)/;
const numberedTaggedTitle = (s) => {
  let match = s.match(numberedTaggedTitleRxp);
  return match && {
    number: match[1] && match[1].split(".")[0],
    title: match[2],
    tag: match[3],
  }
};

const getBaseKey = (transformedSubCategory) => {
  return transformedSubCategory.number ?
    `${transformedSubCategory.number}. ${transformedSubCategory.title}` :
    `${transformedSubCategory.title}`
};

const collectIndicators = (d) => _(d).reduce((accumulator, value, key) => {
  let transformedSubCategory = numberedTaggedTitle(key);
  if (transformedSubCategory) {
    let baseKey = getBaseKey(transformedSubCategory)
    accumulator[transformedSubCategory.title] = {
      vis: parseInt(d[`${baseKey}VIS`]),
      txt: d[`${baseKey}TXT`],
    };
  }
  return accumulator;
}, {});

const transformMetadata = (source) => (m) => {

  const transformedSubCategory = numberedTaggedTitle(m.subCategory);
  const baseKey = getBaseKey(transformedSubCategory);

  return {
    title: m.subCategoryNamingTXT,
    mainCategory: m.belongsToMainCategory,
    slug: transformedSubCategory.title,
    legend: m.subCategoryLegendInfoTXT,
    legendBuckets: _(m).reduce((accumulator, value, key) => {
      let transformedSubCategory = numberedTaggedTitle(key);
      if (value && transformedSubCategory && transformedSubCategory.title === "subCategoryLegendItem") {
        return [...accumulator, {
          vis: parseInt(transformedSubCategory.number)-1,
          txt: value,
        }];
      }
      return accumulator;
    }, []).sort((a,b) => a.vis - b.vis),
    countries: _(source).map((d) => [
      d.countryCode, {
        vis: parseInt(d[`${baseKey}VIS`]),
        txt: d[`${baseKey}TXT`],
      }
    ]).filter(d => d[1].vis).fromPairs().value(),
  }
};

Promise.all([
  fromCSV(fs.readFileSync(files.source)),
  fromCSV(fs.readFileSync(files.meta)),
])
.then(([source, meta]) => meta.map(transformMetadata(source)))
.then((result) => {
  console.log(JSON.stringify(result, null, " "));
});