SaveTool,MassManager: improve staged file updates.

No need to redo the whole staged list when only one file gets updated.
Considering the call to refreshStagedMasses() is blocking (I might look
into threading stuff), its time complexity is O(n) at worst, which can
be bad on slower systems.

src/MassManager/MassManager.cpp

@@ -105,8 +105,8 @@ auto MassManager::exportMass(Int hangar) -> bool {
     }
 
     Containers::String source = Utility::Path::join(_saveDirectory, _hangars[hangar].filename());
-    Containers::String dest = Utility::Path::join(_stagingAreaDirectory,
-                                                  Utility::format("{}_{}.sav", _hangars[hangar].name(), _account));
+    Containers::String dest   = Utility::Path::join(_stagingAreaDirectory,
+                                                    Utility::format("{}_{}.sav", _hangars[hangar].name(), _account));
 
     if(!Utility::Path::copy(source, dest)) {
         _lastError = Utility::format("Couldn't export data from hangar {:.2d} to {}", hangar, dest);
@@ -200,6 +200,26 @@ void MassManager::refreshStagedMasses() {
     }
 }
 
+void MassManager::refreshStagedMass(Containers::StringView filename) {
+    Utility::Debug{} << "Refreshing staged unit with filename" << filename;
+
+    bool file_exists = Utility::Path::exists(Utility::Path::join(_stagingAreaDirectory, filename));
+    auto it = _stagedMasses.find(filename);
+
+    if(file_exists) {
+        auto name = Mass::getNameFromFile(Utility::Path::join(_stagingAreaDirectory, filename));
+        if(name) {
+            _stagedMasses[filename] = *name;
+        }
+        else if(it != _stagedMasses.cend()) {
+            _stagedMasses.erase(it);
+        }
+    }
+    else if(it != _stagedMasses.cend()) {
+        _stagedMasses.erase(it);
+    }
+}
+
 auto MassManager::deleteStagedMass(Containers::StringView filename) -> bool {
     if(_stagedMasses.find(filename) == _stagedMasses.cend()) {
         _lastError = "The file "_s + filename + " couldn't be found in the list of staged M.A.S.S.es."_s;

src/MassManager/MassManager.h

@@ -44,6 +44,7 @@ class MassManager {
 
         auto stagedMasses() -> std::map<Containers::String, Containers::String> const&;
         void refreshStagedMasses();
+        void refreshStagedMass(Containers::StringView filename);
         auto deleteStagedMass(Containers::StringView filename) -> bool;
 
     private:

src/SaveTool/SaveTool.h

@@ -94,7 +94,7 @@ class SaveTool: public Platform::Sdl2Application, public efsw::FileWatchListener
             FileDeleted  = efsw::Action::Delete,
             FileModified = efsw::Action::Modified,
             FileMoved    = efsw::Action::Moved,
-            StagedUpdate
+            StagedUpdate = 1 << 3
         };
         void fileUpdateEvent(SDL_Event& event);
 

src/SaveTool/SaveTool_FileWatcher.cpp

@@ -32,8 +32,10 @@ void SaveTool::handleFileAction(efsw::WatchID watch_id,
     SDL_zero(event);
     event.type = _fileEventId;
 
+    event.user.data1 = Containers::String{Containers::AllocatedInit, filename.c_str()}.release();
+
     if(watch_id == _watchIDs[StagingDir] && Utility::String::endsWith(filename, ".sav")) {
-        event.user.code = StagedUpdate;
+        event.user.code = StagedUpdate | action;
         SDL_PushEvent(&event);
         return;
     }
@@ -47,7 +49,6 @@ void SaveTool::handleFileAction(efsw::WatchID watch_id,
     }
 
     event.user.code = action;
-    event.user.data1 = Containers::String{Containers::AllocatedInit, filename.c_str()}.release();
     if(action == efsw::Actions::Moved) {
         event.user.data2 = Containers::String{Containers::AllocatedInit, old_filename.c_str()}.release();
     }
@@ -56,12 +57,13 @@ void SaveTool::handleFileAction(efsw::WatchID watch_id,
 }
 
 void SaveTool::fileUpdateEvent(SDL_Event& event) {
-    if(event.user.code == StagedUpdate) {
-        _massManager->refreshStagedMasses();
+    Containers::String filename{static_cast<char*>(event.user.data1), std::strlen(static_cast<char*>(event.user.data1)), nullptr};
+
+    if((event.user.code & StagedUpdate) == StagedUpdate) {
+        _massManager->refreshStagedMass(filename);
         return;
     }
 
-    Containers::String filename{static_cast<char*>(event.user.data1), std::strlen(static_cast<char*>(event.user.data1)), nullptr};
     Containers::String old_filename;
 
     Int index = 0;