New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/map/viewport_search_callback.hpp

@@ -0,0 +1,43 @@
+#pragma once
+
+#include "map/viewport_search_params.hpp"
+
+#include "search/result.hpp"
+
+#include "geometry/rect2d.hpp"
+
+#include <functional>
+
+namespace search
+{
+/// @brief An on-results-callback that should be used for interactive search.
+/// @note NOT thread safe.
+class ViewportSearchCallback
+{
+public:
+  class Delegate
+  {
+  public:
+    virtual ~Delegate() = default;
+
+    virtual void RunUITask(std::function<void()> fn) = 0;
+    virtual bool IsViewportSearchActive() const = 0;
+    virtual void ShowViewportSearchResults(Results::ConstIter begin, Results::ConstIter end, bool clear) = 0;
+  };
+
+  using OnResults = ViewportSearchParams::OnCompleted;
+
+  ViewportSearchCallback(m2::RectD const & viewport, Delegate & delegate, OnResults onResults);
+
+  void operator()(Results const & results);
+
+private:
+  m2::RectD m_viewport;
+
+  Delegate & m_delegate;
+  OnResults m_onResults;
+
+  bool m_firstCall;
+  size_t m_lastResultsSize;
+};
+}  // namespace search