Repo created

libs/map/viewport_search_callback.cpp

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+#include "map/viewport_search_callback.hpp"
+
+#include "search/result.hpp"
+
+#include "base/assert.hpp"
+
+namespace search
+{
+ViewportSearchCallback::ViewportSearchCallback(m2::RectD const & viewport, Delegate & delegate, OnResults onResults)
+  : m_viewport(viewport)
+  , m_delegate(delegate)
+  , m_onResults(std::move(onResults))
+  , m_firstCall(true)
+  , m_lastResultsSize(0)
+{
+  // m_onResults may be empty (current Android)
+}
+
+void ViewportSearchCallback::operator()(Results const & results)
+{
+  ASSERT_LESS_OR_EQUAL(m_lastResultsSize, results.GetCount(), ());
+
+  // We need to clear old results and show a new bunch of results when
+  // the search is completed normally (note that there may be empty
+  // set of results), or when the search is not completed and there is
+  // something in results.
+  //
+  // We don't need to clear old results or show current results if the
+  // search is cancelled, because:
+  //
+  // * current request is cancelled because of the next
+  // search-in-viewport request - in this case it is the
+  // responsibility of the next search request to clean up old results
+  // and there is no need to clean up current results. We don't want
+  // to show blinking results.
+  //
+  // * search in viewport may be cancelled completely - it is the
+  // responsibility of the user of this class to handle this case and
+  // clean up results.
+
+  auto & delegate = m_delegate;
+  m_delegate.RunUITask([&delegate, results, onResults = m_onResults, firstCall = m_firstCall,
+                        lastResultsSize = m_lastResultsSize]() mutable
+  {
+    if (delegate.IsViewportSearchActive() &&
+        (results.IsEndedNormal() || (!results.IsEndMarker() && results.GetCount() != 0)))
+    {
+      /// @todo This code relies on fact that results order is *NOT* changing with every new batch.
+      /// I can't say for sure is it true or not, but very optimistic :)
+      /// Much easier to clear previous marks and make new ones.
+      delegate.ShowViewportSearchResults(results.begin() + lastResultsSize, results.end(), firstCall);
+    }
+
+    if (results.IsEndMarker() && onResults)
+      onResults(std::move(results));
+  });
+
+  m_lastResultsSize = results.GetCount();
+  m_firstCall = false;
+}
+}  // namespace search