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web/l10n.js

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+/* Copyright 2023 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/** @typedef {import("./interfaces").IL10n} IL10n */
+
+/**
+ * NOTE: The L10n-implementations should use lowercase language-codes
+ *       internally.
+ * @implements {IL10n}
+ */
+class L10n {
+  #dir;
+
+  #elements;
+
+  #lang;
+
+  #l10n;
+
+  constructor({ lang, isRTL }, l10n = null) {
+    this.#lang = L10n.#fixupLangCode(lang);
+    this.#l10n = l10n;
+    this.#dir = (isRTL ?? L10n.#isRTL(this.#lang)) ? "rtl" : "ltr";
+  }
+
+  _setL10n(l10n) {
+    this.#l10n = l10n;
+    if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("TESTING")) {
+      document.l10n = l10n;
+    }
+  }
+
+  /** @inheritdoc */
+  getLanguage() {
+    return this.#lang;
+  }
+
+  /** @inheritdoc */
+  getDirection() {
+    return this.#dir;
+  }
+
+  /** @inheritdoc */
+  async get(ids, args = null, fallback) {
+    if (Array.isArray(ids)) {
+      ids = ids.map(id => ({ id }));
+      const messages = await this.#l10n.formatMessages(ids);
+      return messages.map(message => message.value);
+    }
+
+    const messages = await this.#l10n.formatMessages([
+      {
+        id: ids,
+        args,
+      },
+    ]);
+    return messages[0]?.value || fallback;
+  }
+
+  /** @inheritdoc */
+  async translate(element) {
+    (this.#elements ||= new Set()).add(element);
+    try {
+      this.#l10n.connectRoot(element);
+      await this.#l10n.translateRoots();
+    } catch {
+      // Element is under an existing root, so there is no need to add it again.
+    }
+  }
+
+  /** @inheritdoc */
+  async translateOnce(element) {
+    try {
+      await this.#l10n.translateElements([element]);
+    } catch (ex) {
+      console.error("translateOnce:", ex);
+    }
+  }
+
+  /** @inheritdoc */
+  async destroy() {
+    if (this.#elements) {
+      for (const element of this.#elements) {
+        this.#l10n.disconnectRoot(element);
+      }
+      this.#elements.clear();
+      this.#elements = null;
+    }
+    this.#l10n.pauseObserving();
+  }
+
+  /** @inheritdoc */
+  pause() {
+    this.#l10n.pauseObserving();
+  }
+
+  /** @inheritdoc */
+  resume() {
+    this.#l10n.resumeObserving();
+  }
+
+  static #fixupLangCode(langCode) {
+    // Use only lowercase language-codes internally, and fallback to English.
+    langCode = langCode?.toLowerCase() || "en-us";
+
+    // Try to support "incompletely" specified language codes (see issue 13689).
+    const PARTIAL_LANG_CODES = {
+      en: "en-us",
+      es: "es-es",
+      fy: "fy-nl",
+      ga: "ga-ie",
+      gu: "gu-in",
+      hi: "hi-in",
+      hy: "hy-am",
+      nb: "nb-no",
+      ne: "ne-np",
+      nn: "nn-no",
+      pa: "pa-in",
+      pt: "pt-pt",
+      sv: "sv-se",
+      zh: "zh-cn",
+    };
+    return PARTIAL_LANG_CODES[langCode] || langCode;
+  }
+
+  static #isRTL(lang) {
+    const shortCode = lang.split("-", 1)[0];
+    return ["ar", "he", "fa", "ps", "ur"].includes(shortCode);
+  }
+}
+
+const GenericL10n = null;
+
+export { GenericL10n, L10n };