i18next/i18next

import baseLogger from './logger.js';
import { getCleanedCode } from './utils.js'

const suffixesOrder = {
  zero: 0,
  one: 1,
  two: 2,
  few: 3,
  many: 4,
  other: 5,
};

const dummyRule = {
  select: (count) => count === 1 ? 'one' : 'other',
  resolvedOptions: () => ({
    pluralCategories: ['one', 'other']
  })
};

class PluralResolver {
  constructor(languageUtils, options = {}) {
    this.languageUtils = languageUtils;
    this.options = options;

    this.logger = baseLogger.create('pluralResolver');

    // Cache calls to Intl.PluralRules, since repeated calls can be slow in runtimes like React Native
    // and the memory usage difference is negligible
    this.pluralRulesCache = {};
  }

  addRule(lng, obj) {
    this.rules[lng] = obj;
  }

  clearCache() {
    this.pluralRulesCache = {};
  }

  getRule(code, options = {}) {
    const cleanedCode = getCleanedCode(code === 'dev' ? 'en' : code);
    const type = options.ordinal ? 'ordinal' : 'cardinal';
    const cacheKey = JSON.stringify({ cleanedCode, type });

    if (cacheKey in this.pluralRulesCache) {
      return this.pluralRulesCache[cacheKey];
    }

    let rule;

    try {
      rule = new Intl.PluralRules(cleanedCode, { type });
    } catch (err) {
      if (!Intl) {
        this.logger.error('No Intl support, please use an Intl polyfill!');
        return dummyRule;
      }
      if (!code.match(/-|_/)) return dummyRule;
      const lngPart = this.languageUtils.getLanguagePartFromCode(code);
      rule = this.getRule(lngPart, options);
    }

    this.pluralRulesCache[cacheKey] = rule;
    return rule;
  }

  needsPlural(code, options = {}) {
    let rule = this.getRule(code, options);
    if (!rule) rule = this.getRule('dev', options);
    return rule?.resolvedOptions().pluralCategories.length > 1;
  }

  getPluralFormsOfKey(code, key, options = {}) {
    return this.getSuffixes(code, options).map((suffix) => `${key}${suffix}`);
  }

  getSuffixes(code, options = {}) {
    let rule = this.getRule(code, options);
    if (!rule) rule = this.getRule('dev', options);
    if (!rule) return [];

    return rule.resolvedOptions().pluralCategories
      .sort((pluralCategory1, pluralCategory2) => suffixesOrder[pluralCategory1] - suffixesOrder[pluralCategory2])
      .map(pluralCategory => `${this.options.prepend}${options.ordinal ? `ordinal${this.options.prepend}` : ''}${pluralCategory}`);
  }

  getSuffix(code, count, options = {}) {
    const rule = this.getRule(code, options);

    if (rule) {
      return `${this.options.prepend}${options.ordinal ? `ordinal${this.options.prepend}` : ''}${rule.select(count)}`;
    }

    this.logger.warn(`no plural rule found for: ${code}`);
    return this.getSuffix('dev', count, options);
  }
}

export default PluralResolver;