ProportionNormalizer.ts

import _ = require('lodash');
import Utils = require('../calculators/Utils');

class ProportionNormalizer {
  static getLabelMatchingAbbreviation(normalizedLabel: string, abbreviations: Mapping): string | null {
    const matchingAbbreviation = _.find(
      _.keys(abbreviations),
      (abbreviation) =>
        abbreviation === normalizedLabel ||
        new RegExp(`^${abbreviation}[- ]`).test(normalizedLabel) ||
        new RegExp(`[- ]${abbreviation}$`).test(normalizedLabel)
    );
    return matchingAbbreviation ? abbreviations[matchingAbbreviation] : null;
  }

  normalize(proportions: Proportion[], totalWithValue: number, valueMappings: NormalizerMappings): Proportion[] {
    const mergedLabels: { [label: string]: boolean } = {};
    const { aliases, abbreviations } = valueMappings;

    return _.chain(proportions)
      .map((proportion, proportionIndex) => {
        // Ignore merged proportions
        if (mergedLabels[proportion.label]) {
          return null;
        }

        // Ignore unknown values
        if (proportion.label === '') {
          return null;
        }

        // Add following proportions' values that should be merged to current proportion's value
        const normalizedLabel = proportion.label.toLowerCase();
        const followingProportions = _.drop(proportions, proportionIndex + 1);
        const normalizedCount = followingProportions.reduce((currentCount, followingProportion) => {
          const normalizedFollowingLabel = followingProportion.label.toLowerCase();
          if (
            aliases[normalizedFollowingLabel] === normalizedLabel ||
            normalizedFollowingLabel.includes(normalizedLabel) ||
            ProportionNormalizer.getLabelMatchingAbbreviation(normalizedFollowingLabel, abbreviations) ===
              normalizedLabel
          ) {
            mergedLabels[followingProportion.label] = true;
            return currentCount + followingProportion.count;
          }
          return currentCount;
        }, proportion.count);

        return {
          ...proportion,
          count: normalizedCount,
          percentage: Utils.renderPercentage(normalizedCount, totalWithValue),
        };
      })
      .compact()
      .sortBy('count')
      .reverse()
      .value();
  }
}

export = ProportionNormalizer;