Repo created

libs/search/query_saver.cpp

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+#include "query_saver.hpp"
+
+#include "platform/settings.hpp"
+
+#include "coding/base64.hpp"
+#include "coding/reader.hpp"
+#include "coding/write_to_sink.hpp"
+#include "coding/writer.hpp"
+
+#include "base/checked_cast.hpp"
+#include "base/logging.hpp"
+#include "base/string_utils.hpp"
+
+#include <limits>
+#include <memory>
+
+namespace search
+{
+using namespace std;
+
+namespace
+{
+std::string_view constexpr kSettingsKey = "UserQueries";
+using Length = uint16_t;
+Length constexpr kMaxSuggestionsCount = 50;
+
+// Reader from memory that throws exceptions.
+class SecureMemReader : public Reader
+{
+  void CheckPosAndSize(uint64_t pos, uint64_t size) const
+  {
+    if (pos + size > m_size || size > numeric_limits<size_t>::max())
+      MYTHROW(SizeException, (pos, size, m_size));
+  }
+
+public:
+  // Construct from block of memory.
+  SecureMemReader(void const * pData, size_t size) : m_pData(static_cast<char const *>(pData)), m_size(size) {}
+
+  inline uint64_t Size() const override { return m_size; }
+
+  inline void Read(uint64_t pos, void * p, size_t size) const override
+  {
+    CheckPosAndSize(pos, size);
+    memcpy(p, m_pData + pos, size);
+  }
+
+  inline SecureMemReader SubReader(uint64_t pos, uint64_t size) const
+  {
+    CheckPosAndSize(pos, size);
+    return SecureMemReader(m_pData + pos, static_cast<size_t>(size));
+  }
+
+  inline unique_ptr<Reader> CreateSubReader(uint64_t pos, uint64_t size) const override
+  {
+    CheckPosAndSize(pos, size);
+    return make_unique<SecureMemReader>(m_pData + pos, static_cast<size_t>(size));
+  }
+
+private:
+  char const * m_pData;
+  size_t m_size;
+};
+}  // namespace
+
+QuerySaver::QuerySaver()
+{
+  Load();
+}
+
+void QuerySaver::Add(SearchRequest const & query)
+{
+  // This change was made just before release, so we don't use untested search normalization methods.
+  // TODO (ldragunov) Rewrite to normalized requests.
+  SearchRequest trimmedQuery(query);
+  strings::Trim(trimmedQuery.first);
+  strings::Trim(trimmedQuery.second);
+  auto trimmedComparator = [&trimmedQuery](SearchRequest request)
+  {
+    strings::Trim(request.first);
+    strings::Trim(request.second);
+    return trimmedQuery == request;
+  };
+  // Remove items if needed.
+  auto const it = find_if(m_topQueries.begin(), m_topQueries.end(), trimmedComparator);
+  if (it != m_topQueries.end())
+    m_topQueries.erase(it);
+  else if (m_topQueries.size() >= kMaxSuggestionsCount)
+    m_topQueries.pop_back();
+
+  // Add new query and save it to drive.
+  m_topQueries.push_front(query);
+  Save();
+}
+
+void QuerySaver::Clear()
+{
+  m_topQueries.clear();
+  settings::Delete(kSettingsKey);
+}
+
+void QuerySaver::Serialize(string & data) const
+{
+  vector<uint8_t> rawData;
+  MemWriter<vector<uint8_t>> writer(rawData);
+  auto size = base::checked_cast<Length>(m_topQueries.size());
+  WriteToSink(writer, size);
+  for (auto const & query : m_topQueries)
+  {
+    size = base::checked_cast<Length>(query.first.size());
+    WriteToSink(writer, size);
+    writer.Write(query.first.c_str(), size);
+    size = base::checked_cast<Length>(query.second.size());
+    WriteToSink(writer, size);
+    writer.Write(query.second.c_str(), size);
+  }
+  data = base64::Encode(string(rawData.begin(), rawData.end()));
+}
+
+void QuerySaver::Deserialize(string const & data)
+{
+  string decodedData = base64::Decode(data);
+  SecureMemReader rawReader(decodedData.c_str(), decodedData.size());
+  ReaderSource<SecureMemReader> reader(rawReader);
+
+  Length queriesCount = ReadPrimitiveFromSource<Length>(reader);
+  queriesCount = min(queriesCount, kMaxSuggestionsCount);
+
+  for (Length i = 0; i < queriesCount; ++i)
+  {
+    Length localeLength = ReadPrimitiveFromSource<Length>(reader);
+    vector<char> locale(localeLength);
+    reader.Read(&locale[0], localeLength);
+    Length stringLength = ReadPrimitiveFromSource<Length>(reader);
+    vector<char> str(stringLength);
+    reader.Read(&str[0], stringLength);
+    m_topQueries.emplace_back(make_pair(string(&locale[0], localeLength), string(&str[0], stringLength)));
+  }
+}
+
+void QuerySaver::Save()
+{
+  string data;
+  Serialize(data);
+  settings::Set(kSettingsKey, data);
+}
+
+void QuerySaver::Load()
+{
+  string hexData;
+  if (!settings::Get(kSettingsKey, hexData) || hexData.empty())
+    return;
+
+  try
+  {
+    Deserialize(hexData);
+  }
+  catch (RootException const &)
+  {
+    Clear();
+    LOG(LWARNING, ("Search history data corrupted! Creating new one."));
+  }
+}
+}  // namespace search