adblockplusopera: Port UI code from Chrome

background.js

Index: background.js
===================================================================
--- a/background.js
+++ b/background.js
@@ -1,8 +1,12 @@
+var DownloadableSubscription = require("subscriptionClasses").DownloadableSubscription;
+var WhitelistFilter = require("filterClasses").WhitelistFilter;
 var FilterNotifier = require("filterNotifier").FilterNotifier;
 var FilterStorage = require("filterStorage").FilterStorage;
+var Prefs = require("prefs").Prefs;
 var Synchronizer = require("synchronizer").Synchronizer;
 var Subscription = require("subscriptionClasses").Subscription;
-var DownloadableSubscription = require("subscriptionClasses").DownloadableSubscription;
+var SpecialSubscription = require("subscriptionClasses").SpecialSubscription;
+var Utils = require("utils").Utils;
 
 var isFirstRun = false;
 FilterNotifier.addListener(function(action)
@@ -19,6 +23,9 @@
   }
 });
 
+var toolbarButton;
+var i18nMessages;
+
 function importOldData()
 {
   // TODO: Remove this once most people have the update
@@ -144,3 +151,82 @@
   };
   request.send(null);
 }
+
+function setDefaultOptions()
+{
+  function defaultOptionValue(opt, val)
+  {
+    if(!(opt in localStorage))
+      localStorage[opt] = val;
+  }
+
+  defaultOptionValue("shouldShowIcon", "true");
+}
+
+function createToolbarButton()
+{
+  var properties = {
+    disabled: false,
+    title: "Adblock Plus",
+    icon: "icons/abp-18.png"
+  };
+
+  toolbarButton = opera.contexts.toolbar.createItem(properties);
+}
+
+function refreshToolbarButton()
+{
+  var toolbar = opera.contexts.toolbar;
+  if (localStorage["shouldShowIcon"] === "true")
+    toolbar.addItem(toolbarButton);
+  else
+    toolbar.removeItem(toolbarButton);
+}
+
+function getJson(url)
+{
+  var request = new XMLHttpRequest();
+  request.open("GET", url, false);
+  request.responseType = "json";
+  request.send();
+  return request.response;
+}
+
+function loadMessagesForLocale(locale)
+{
+  var messagesFileName = "messages.json";
+  var messagesPath;
+  if (locale)
+    messagesPath = "locales/" + locale + "/" + messagesFileName;
+  else
+    messagesPath = messagesFileName;
+
+  var messages = getJson(messagesPath);
+  if (!messages)
+  {
+    console.error("Failed to load messages for locale "
+                  + (locale ? locale : "default"));
+    return;
+  }
+
+  for (var i in messages)
+    i18nMessages[i] = messages[i];
+}
+
+function loadI18nMessages()
+{
+  i18nMessages = {};
+
+  // Could be parsed from config.xml
+  var defaultLocale = "en";
+
+  if (locale !== defaultLocale)
+    loadMessagesForLocale(defaultLocale);
+
+  loadMessagesForLocale();
+}
+
+setDefaultOptions();
+createToolbarButton();
+refreshToolbarButton();
+loadI18nMessages();