i18n-options.ts

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
import { json } from '@angular-devkit/core';

export interface I18nOptions {
  inlineLocales: Set<string>;
  sourceLocale: string;
  locales: Record<string, { file: string; format?: string; translation?: unknown }>;
  flatOutput?: boolean;
  readonly shouldInline: boolean;
}

export function createI18nOptions(
  metadata: json.JsonObject,
  inline?: boolean | string[],
): I18nOptions {
  if (
    metadata.i18n !== undefined &&
    (typeof metadata.i18n !== 'object' || !metadata.i18n || Array.isArray(metadata.i18n))
  ) {
    throw new Error('Project i18n field is malformed. Expected an object.');
  }
  metadata = metadata.i18n || {};

  if (metadata.sourceLocale !== undefined && typeof metadata.sourceLocale !== 'string') {
    throw new Error('Project i18n sourceLocale field is malformed. Expected a string.');
  }

  const i18n: I18nOptions = {
    inlineLocales: new Set<string>(),
    // en-US is the default locale added to Angular applications (https://angular.io/guide/i18n#i18n-pipes)
    sourceLocale: metadata.sourceLocale || 'en-US',
    locales: {},
    get shouldInline() {
      return this.inlineLocales.size > 0;
    },
  };

  if (
    metadata.locales !== undefined &&
    (!metadata.locales || typeof metadata.locales !== 'object' || Array.isArray(metadata.locales))
  ) {
    throw new Error('Project i18n locales field is malformed. Expected an object.');
  } else if (metadata.locales) {
    for (const [locale, translationFile] of Object.entries(metadata.locales)) {
      if (typeof translationFile !== 'string') {
        throw new Error(
          `Project i18n locales field value for '${locale}' is malformed. Expected a string.`,
        );
      }

      if (locale === i18n.sourceLocale) {
        throw new Error(
          `An i18n locale identifier ('${locale}') cannot both be a source locale and provide a translation.`,
        );
      }

      i18n.locales[locale] = {
        file: translationFile,
      };
    }
  }

  if (inline === true) {
    i18n.inlineLocales.add(i18n.sourceLocale);
    Object.keys(i18n.locales).forEach(locale => i18n.inlineLocales.add(locale));
  } else if (inline) {
    for (const locale of inline) {
      if (!i18n.locales[locale]) {
        throw new Error(`Requested inline locale '${locale}' is not defined for the project.`);
      }

      i18n.inlineLocales.add(locale);
    }
  }

  return i18n;
}

export function mergeDeprecatedI18nOptions(i18n: I18nOptions, i18nLocale: string | undefined, i18nFile: string | undefined): I18nOptions {
  if (i18nFile !== undefined && i18nLocale === undefined) {
    throw new Error(`Option 'i18nFile' cannot be used without the 'i18nLocale' option.`);
  }

  if (i18nLocale !== undefined) {
    i18n.inlineLocales.clear();
    i18n.inlineLocales.add(i18nLocale);

    if (i18nFile !== undefined) {
      i18n.locales[i18nLocale] = { file: i18nFile };
      i18n.flatOutput = true;
    }
  }

  return i18n;
}