Issue 5028 - Use browser namespace

polyfill.js

Index: polyfill.js
===================================================================
new file mode 100644
--- /dev/null
+++ b/polyfill.js
@@ -0,0 +1,140 @@
+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-present eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+"use strict";
+
+(function()
+{
+  window.browser = {};

[Sebastian Noack, 2017/10/13 21:39:23]

Nit: Perhaps we should just define the "browser" object inline below?

  window.browser = {
    i18n: {
      ...
    }
  };

[Manish Jethani, 2017/10/13 22:30:24]

There will be more polyfills in this file (see
https://codereview.adblockplus.org/29573905/) so I think it's easier to group
them with their helper functions. Here browser.i18n needs getLocaleCandidates,
later browser.runtime would need its sendRawMessage (as well as some variables,
like the message ID for tracking, etc.). I'm OK with doing it either way, but it
just seems better to group all the i18n code together here.

+
+  /* I18n */
+
+  let getLocaleCandidates = function(selectedLocale)
+  {
+    let candidates = [];
+    let defaultLocale = "en-US";

[saroyanm, 2017/10/16 19:24:20]

Heads-up for the rebase: There were couple of changes that affected this code ->
https://hg.adblockplus.org/adblockplusui/rev/070c26efe1c1

[Manish Jethani, 2017/10/16 21:35:21]

Done.

+
+    // e.g. "ja-jp-mac" -> "ja-JP", note that the part after the second
+    // dash is dropped, since we only support language and region
+    let parts = selectedLocale.split("-");
+    let language = parts[0];
+    let region = (parts[1] || "").toUpperCase();
+
+    if (region)
+      candidates.push(language + "-" + region);
+
+    candidates.push(language);
+
+    if (candidates.indexOf(defaultLocale) == -1)
+      candidates.push(defaultLocale);
+
+    return candidates;
+  };
+
+  let selectedLocale = window.navigator.language;
+  let match = /[?&]locale=([\w-]+)/.exec(window.location.search);
+  if (match)
+    selectedLocale = match[1];
+
+  let locales = getLocaleCandidates(selectedLocale);
+  let catalog = Object.create(null);
+  let catalogFile = window.location.pathname.replace(/.*\//, "")
+    .replace(/\..*/, "") + ".json";
+
+  let replacePlaceholder = function(text, placeholder, content)
+  {
+    return text.split("$" + placeholder + "$").join(content || "");
+  };
+
+  let parseMessage = function(rawMessage)
+  {
+    let text = rawMessage.message;
+    let placeholders = [];
+
+    for (let placeholder in rawMessage.placeholders)
+    {
+      let {content} = rawMessage.placeholders[placeholder];
+
+      if (/^\$\d+$/.test(content))
+        placeholders[parseInt(content.substr(1), 10) - 1] = placeholder;
+      else
+        text = replacePlaceholder(text, placeholder, content);
+    }
+
+    return [text, placeholders];
+  };
+
+  let readCatalog = function(locale, file)
+  {
+    let xhr = new XMLHttpRequest();
+    xhr.open("GET", "locale/" + locale + "/" + file, false);
+    xhr.overrideMimeType("text/plain");
+
+    try
+    {
+      xhr.send();
+    }
+    catch (e)
+    {
+      return;
+    }
+
+    if (xhr.status != 200 && xhr.status != 0)
+      return;
+
+    let rawCatalog = JSON.parse(xhr.responseText);
+    for (let msgId in rawCatalog)
+    {
+      if (!(msgId in catalog))
+        catalog[msgId] = parseMessage(rawCatalog[msgId]);
+    }
+  };
+
+  browser.i18n = {
+    getUILanguage()
+    {
+      return locales[0].replace(/_/g, "-");
+    },
+    getMessage(msgId, substitutions)
+    {
+      while (true)
+      {
+        let message = catalog[msgId];
+        if (message)
+        {
+          let text = message[0];
+          let placeholders = message[1];
+
+          if (!(substitutions instanceof Array))
+            substitutions = [substitutions];
+
+          for (let i = 0; i < placeholders.length; i++)
+            text = replacePlaceholder(text, placeholders[i], substitutions[i]);
+
+          return text;
+        }
+
+        if (locales.length == 0)
+          return "";
+
+        let locale = locales.shift();
+        readCatalog(locale, "common.json");
+        readCatalog(locale, catalogFile);
+      }
+    }
+  };
+}());