Add API calls and stubs for filter matching and subscription management

src/FilterEngine.cpp

Index: src/FilterEngine.cpp
===================================================================
new file mode 100644
--- /dev/null
+++ b/src/FilterEngine.cpp
@@ -0,0 +1,70 @@
+#include <AdblockPlus.h>
+
+using namespace AdblockPlus;
+
+Subscription::Subscription(const std::string& url, const std::string& title)
+  : url(url), title(title)
+{
+}
+
+FilterEngine::FilterEngine(JsEngine& jsEngine) : jsEngine(jsEngine)
+{
+  // TODO: Load ABP:
+  // jsEngine.Load("adblockplus_compat.js");
+  // jsEngine.Load("adblockplus.js");
+}
+
+void FilterEngine::AddSubscription(Subscription subscription)
+{
+  subscriptions.push_back(subscription);
+}
+
+void FilterEngine::RemoveSubscription(const Subscription& subscription)
+{
+  for (std::vector<Subscription>::iterator it = subscriptions.begin();
+       it != subscriptions.end();)
+    if (it->url == subscription.url)
+      it = subscriptions.erase(it);
+    else
+      it++;
+}
+
+const Subscription* FilterEngine::FindSubscription(const std::string& url) const
+{
+  for (std::vector<Subscription>::const_iterator it = subscriptions.begin();
+       it != subscriptions.end(); it++)
+    if (it->url == url)
+      return &(*it);
+  return 0;
+}
+
+const std::vector<Subscription>& FilterEngine::GetSubscriptions() const
+{
+  return subscriptions;
+}
+
+void FilterEngine::UpdateSubscriptionFilters(const Subscription& subscription)
+{
+}
+
+std::vector<Subscription> FilterEngine::FetchAvailableSubscriptions()
+{
+  std::vector<Subscription> availableSubscriptions;
+  availableSubscriptions.push_back(Subscription("https://easylist-downloads.adblockplus.org/easylist.txt", "EasyList"));
+  availableSubscriptions.push_back(Subscription("https://easylist-downloads.adblockplus.org/easylistgermany+easylist.txt", "EasyList Germany+EasyList"));
+  return availableSubscriptions;
+}
+
+bool FilterEngine::Matches(const std::string& url,
+                           const std::string& contentType) const
+{
+  return subscriptions.size() && url.length() % 2;
+}
+
+std::vector<std::string> FilterEngine::GetElementHidingRules() const
+{
+  std::vector<std::string> hidingRules;
+  hidingRules.push_back("###ad");
+  hidingRules.push_back("##.ad");
+  return hidingRules;
+}