Issue 4944 - Make creation of FilterEngine asynchronous.

include/AdblockPlus/FilterEngine.h

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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
@@ skipping 11 matching lines @@
 #include <map>
 #include <string>
 #include <vector>
 #include <AdblockPlus/JsEngine.h>
 #include <AdblockPlus/JsValue.h>
 #include <AdblockPlus/Notification.h>
 
 namespace AdblockPlus
 {
   class FilterEngine;
+  typedef std::shared_ptr<FilterEngine> FilterEnginePtr;
 
   /**
    * Wrapper for an Adblock Plus filter object.
    * There are no accessors for most
    * [filter properties](https://adblockplus.org/jsdoc/adblockpluscore/Filter.html),
    * use `GetProperty()` to retrieve them by name.
    */
   class Filter : public JsValue,
                  public std::enable_shared_from_this<Filter>
   {
@@ skipping 164 matching lines @@
      */
     typedef std::map<std::string, AdblockPlus::JsValuePtr> Prefs;
 
     /**
      * Callback type invoked when a new notification should be shown.
      * The parameter is the Notification object to be shown.
      */
     typedef std::function<void(const NotificationPtr&)> ShowNotificationCallback;
 
     /**
-     * Constructor.
+     * FilterEngine creation parameters.
+     */
+    struct CreationParameters
+    {
+      /**
+       * `AdblockPlus::FilterEngine::Prefs` name - value list of preconfigured
+       * prefs.
+       */
+      Prefs preconfiguredPrefs;
+    };
+
+    /**
+    * Callback type invoked when FilterEngine is created.
+    */
+    typedef std::function<void(const FilterEnginePtr&)> OnCreatedCallback;
+
+    /**
+     * Asynchronously constructs FilterEngine.
      * @param jsEngine `JsEngine` instance used to run JavaScript code
      *        internally.
-     * @param preconfiguredPrefs `AdblockPlus::FilterEngine::Prefs`
-     *        name-value list of preconfigured prefs.
+     * @param onCreated A callback which is called when FilterEngine is ready
+     *        for use.
+     * @param parameters optional creation parameters.
      */
-    explicit FilterEngine(JsEnginePtr jsEngine, 
-        const Prefs& preconfiguredPrefs = Prefs()
-      );
+    static void CreateAsync(const JsEnginePtr& jsEngine,
+      const OnCreatedCallback& onCreated,
+      const CreationParameters& parameters = CreationParameters());
+
+    /**
+     * Synchronous interface to construct FilterEngine. For details see
+     * asynchronous version CreateAsync.
+     */
+    static FilterEnginePtr Create(const JsEnginePtr& jsEngine,
+      const CreationParameters& params = CreationParameters());
 
     /**
      * Retrieves the `JsEngine` instance associated with this `FilterEngine`
      * instance.
      */
     JsEnginePtr GetJsEngine() const { return jsEngine; }
 
     /**
      * Checks if this is the first run of the application.
      * @return `true` if the application is running for the first time.
@@ skipping 200 matching lines @@
     /**
      * Retrieves the string representation of the supplied `ContentType`.
      * @param contentType `ContentType` value.
      * @return The string representation of `contentType`.
      * @throw `std::invalid_argument`, if an invalid `contentType` was supplied.
      */
     static std::string ContentTypeToString(ContentType contentType);
 
   private:
     JsEnginePtr jsEngine;
-    bool initialized;
     bool firstRun;
     int updateCheckId;
     static const std::map<ContentType, std::string> contentTypes;
 
-    void InitDone(JsValueList& params);
+    explicit FilterEngine(const JsEnginePtr& jsEngine);
+
     FilterPtr CheckFilterMatch(const std::string& url,
                                ContentTypeMask contentTypeMask,
                                const std::string& documentUrl) const;
     void UpdateAvailable(UpdateAvailableCallback callback, JsValueList& params);
     void UpdateCheckDone(const std::string& eventName,
                          UpdateCheckDoneCallback callback, JsValueList& params);
     void FilterChanged(FilterChangeCallback callback, JsValueList& params);
     void ShowNotification(const ShowNotificationCallback& callback,
       const JsValueList& params);
     FilterPtr GetWhitelistingFilter(const std::string& url,
       ContentTypeMask contentTypeMask, const std::string& documentUrl) const;
     FilterPtr GetWhitelistingFilter(const std::string& url,
       ContentTypeMask contentTypeMask,
       const std::vector<std::string>& documentUrls) const;
   };
 }
 
 #endif