Calculating correct value of max mwm size.

android/jni/com/mapswithme/maps/MapManager.cpp

@@ -103,7 +103,7 @@ Java_com_mapswithme_maps_downloader_MapManager_nativeHasSpaceForMigration(JNIEnv
 JNIEXPORT jboolean JNICALL
 Java_com_mapswithme_maps_downloader_MapManager_nativeHasSpaceToDownloadAmount(JNIEnv * env, jclass clazz, jlong bytes)
 {
-  return IsEnoughSpaceForDownload(bytes);
+  return IsEnoughSpaceForDownload(bytes, GetStorage().GetMaxMwmSizeBytes());
 }
 
 // static boolean nativeHasSpaceToDownloadCountry(String root);

iphone/Maps/Core/Storage/MWMStorage.mm

@@ -81,7 +81,8 @@ using namespace storage;
 }
 + (void)downloadNodes:(TCountriesVec const &)countryIds onSuccess:(MWMVoidBlock)onSuccess
 {
-  TMwmSize requiredSize = accumulate(countryIds.begin(), countryIds.end(), kMaxMwmSizeBytes,
+  auto & s = GetFramework().GetStorage();
+  TMwmSize requiredSize = accumulate(countryIds.begin(), countryIds.end(), s.GetMaxMwmSizeBytes(),
                                      [](size_t const & size, TCountryId const & countryId)
                                      {
                                        NodeAttrs nodeAttrs;
@@ -90,8 +91,7 @@ using namespace storage;
                                      });
   if (storage::IsEnoughSpaceForDownload(requiredSize))
   {
-    [self checkConnectionAndPerformAction:[countryIds, onSuccess] {
-      auto & s = GetFramework().GetStorage();
+    [self checkConnectionAndPerformAction:[countryIds, onSuccess, &s] {
       for (auto const & countryId : countryIds)
         s.DownloadNode(countryId);
       if (onSuccess)

map/framework.cpp

@@ -341,7 +341,8 @@ void Framework::StopLocationFollow()
 
 bool Framework::IsEnoughSpaceForMigrate() const
 {
-  return GetPlatform().GetWritableStorageStatus(kMaxMwmSizeBytes) == Platform::TStorageStatus::STORAGE_OK;
+  return GetPlatform().GetWritableStorageStatus(GetStorage().GetMaxMwmSizeBytes()) ==
+         Platform::TStorageStatus::STORAGE_OK;
 }
 
 TCountryId Framework::PreMigrate(ms::LatLon const & position,

storage/storage.cpp

@@ -114,18 +114,24 @@ Storage::Storage(string const & pathToCountriesFile /* = COUNTRIES_FILE */,
   , m_currentSlotId(0)
   , m_dataDir(dataDir)
   , m_downloadMapOnTheMap(nullptr)
+  , m_maxMwmSizeBytes(0)
 {
   SetLocale(languages::GetCurrentTwine());
   LoadCountriesFile(pathToCountriesFile, m_dataDir);
+  CalMaxMwmSizeBytes();
 }
 
 Storage::Storage(string const & referenceCountriesTxtJsonForTesting,
                  unique_ptr<MapFilesDownloader> mapDownloaderForTesting)
-  : m_downloader(move(mapDownloaderForTesting)), m_currentSlotId(0), m_downloadMapOnTheMap(nullptr)
+  : m_downloader(move(mapDownloaderForTesting))
+  , m_currentSlotId(0)
+  , m_downloadMapOnTheMap(nullptr)
+  , m_maxMwmSizeBytes(0)
 {
   m_currentVersion =
       LoadCountries(referenceCountriesTxtJsonForTesting, m_countries, m_affiliations);
   CHECK_LESS_OR_EQUAL(0, m_currentVersion, ("Can't load test countries file"));
+  CalMaxMwmSizeBytes();
 }
 
 void Storage::Init(TUpdateCallback const & didDownload, TDeleteCallback const & willDelete)
@@ -1310,6 +1316,19 @@ bool Storage::IsDisputed(TCountryTreeNode const & node) const
   return found.size() > 1;
 }
 
+void Storage::CalMaxMwmSizeBytes()
+{
+  m_maxMwmSizeBytes = 0;
+  m_countries.GetRoot().ForEachInSubtree([&](TCountryTree::Node const & node) {
+    if (node.ChildrenCount() == 0)
+    {
+      TMwmSize mwmSizeBytes = node.Value().GetSubtreeMwmSizeBytes();
+      if (mwmSizeBytes > m_maxMwmSizeBytes)
+        m_maxMwmSizeBytes = mwmSizeBytes;
+    }
+  });
+}
+
 StatusAndError Storage::GetNodeStatusInfo(
     TCountryTreeNode const & node, vector<pair<TCountryId, NodeStatus>> & disputedTerritories,
                                           bool isDisputedTerritoriesCounted) const

storage/storage.hpp

@@ -240,6 +240,8 @@ private:
   // Note. |m_affiliations| is empty in case of countries_obsolete.txt.
   TMappingAffiliations m_affiliations;
 
+  TMwmSize m_maxMwmSizeBytes;
+
   ThreadChecker m_threadChecker;
 
   void DownloadNextCountryFromQueue();
@@ -532,6 +534,8 @@ public:
   /// Sets and gets locale, which is used to get localized counries names
   void SetLocale(string const & locale);
   string GetLocale() const;
+  
+  TMwmSize GetMaxMwmSizeBytes() const { return m_maxMwmSizeBytes; }
 
   // for testing:
   void SetDownloaderForTesting(unique_ptr<MapFilesDownloader> && downloader);
@@ -635,6 +639,8 @@ private:
   void ForEachAncestorExceptForTheRoot(vector<TCountryTreeNode const *> const & nodes, ToDo && toDo) const;
   /// Returns true if |node.Value().Name()| is a disputed territory and false otherwise.
   bool IsDisputed(TCountryTreeNode const & node) const;
+
+  void CalMaxMwmSizeBytes();
 };
 
 void GetQueuedCountries(Storage::TQueue const & queue, TCountriesSet & resultCountries);

storage/storage_helpers.cpp

@@ -20,12 +20,12 @@ bool IsDownloadFailed(Status status)
          status == Status::EUnknown;
 }
 
-bool IsEnoughSpaceForDownload(TMwmSize size)
+bool IsEnoughSpaceForDownload(TMwmSize mwmSize, TMwmSize maxMwmSize)
 {
-  // Mwm size is less than kMaxMwmSizeBytes. In case of map update at first we download updated map
+  // Mwm size is less than |maxMwmSize|. In case of map update at first we download updated map
   // and only after that we do delete the obsolete map. So in such a case we might need up to
   // kMaxMwmSizeBytes of extra space.
-  return GetPlatform().GetWritableStorageStatus(size + kMaxMwmSizeBytes) ==
+  return GetPlatform().GetWritableStorageStatus(mwmSize + maxMwmSize) ==
          Platform::TStorageStatus::STORAGE_OK;
 }
 
@@ -35,7 +35,7 @@ bool IsEnoughSpaceForDownload(TCountryId const & countryId, Storage const & stor
   storage.GetNodeAttrs(countryId, nodeAttrs);
   return IsEnoughSpaceForDownload(nodeAttrs.m_mwmSize > nodeAttrs.m_localMwmSize
                                       ? nodeAttrs.m_mwmSize - nodeAttrs.m_localMwmSize
-                                      : 0);
+                                      : 0, storage.GetMaxMwmSizeBytes());
 }
 
 bool IsEnoughSpaceForUpdate(TCountryId const & countryId, Storage const & storage)
@@ -44,7 +44,7 @@ bool IsEnoughSpaceForUpdate(TCountryId const & countryId, Storage const & storag
   
   storage.GetUpdateInfo(countryId, updateInfo);
   TMwmSize spaceNeedForUpdate = updateInfo.m_sizeDifference > 0 ? updateInfo.m_sizeDifference : 0;
-  return IsEnoughSpaceForDownload(spaceNeedForUpdate);
+  return IsEnoughSpaceForDownload(spaceNeedForUpdate, storage.GetMaxMwmSizeBytes());
 }
 
 m2::RectD CalcLimitRect(TCountryId const & countryId,

storage/storage_helpers.hpp

@@ -13,8 +13,6 @@ namespace storage
 class CountryInfoGetter;
 class Storage;
 
-TMwmSize constexpr kMaxMwmSizeBytes = 100 /*Mb*/ * 1024 * 1024;
-
 /// \returns true if |position| is covered by a downloaded mwms and false otherwise.
 /// \note |position| has coordinates in mercator.
 /// \note This method takes into acount only maps enumerated in countries.txt.
@@ -24,7 +22,7 @@ bool IsPointCoveredByDownloadedMaps(m2::PointD const & position,
 
 bool IsDownloadFailed(Status status);
 
-bool IsEnoughSpaceForDownload(TMwmSize size);
+bool IsEnoughSpaceForDownload(TMwmSize mwmSize, TMwmSize maxMwmSize);
 bool IsEnoughSpaceForDownload(TCountryId const & countryId, Storage const & storage);
 bool IsEnoughSpaceForUpdate(TCountryId const & countryId, Storage const & storage);