Move most of the autosave logic to AssFile and only autosave if there's actually been changes since the last autosave

Originally committed to SVN as r5680.

aegisub/src/ass_file.cpp

@@ -69,7 +69,7 @@ namespace std {
 
 /// @brief AssFile constructor
 AssFile::AssFile ()
-: commitId(-1)
+: commitId(0)
 , loaded(false)
 {
 }
@@ -152,9 +152,8 @@ void AssFile::Load(const wxString &_filename,wxString charset,bool addToRecent)
 	UndoStack.clear();
 	RedoStack.clear();
 	undoDescription.clear();
-	commitId = -1;
-	savedCommitId = 0;
 	Commit("", COMMIT_NEW);
+	savedCommitId = commitId;
 
 	// Add to recent
 	if (addToRecent) AddToRecent(filename);
@@ -181,6 +180,35 @@ void AssFile::Save(wxString filename, bool setfilename, bool addToRecent, wxStri
 	}
 }
 
+wxString AssFile::AutoSave() {
+	if (!loaded || commitId == autosavedCommitId)
+		return "";
+
+	wxFileName origfile(filename);
+	wxString path = lagi_wxString(OPT_GET("Path/Auto/Save")->GetString());
+	if (!path)
+		path = origfile.GetPath();
+
+	wxFileName dstpath(path);
+	if (!dstpath.IsAbsolute())
+		path = StandardPaths::DecodePathMaybeRelative(path, "?user/");
+	dstpath.AssignDir(path);
+	if (!dstpath.DirExists())
+		wxMkdir(path);
+
+	wxString name = origfile.GetName();
+	if (name.empty())
+		dstpath.SetFullName("Untitled.AUTOSAVE.ass");
+	else
+		dstpath.SetFullName(name + ".AUTOSAVE.ass");
+
+	Save(dstpath.GetFullPath(), false, false);
+
+	autosavedCommitId = commitId;
+
+	return dstpath.GetFullPath();
+}
+
 void AssFile::SaveMemory(std::vector<char> &dst,const wxString encoding) {
 	// Set encoding
 	wxString enc = encoding;
@@ -420,8 +448,6 @@ void AssFile::Clear() {
 	UndoStack.clear();
 	RedoStack.clear();
 	undoDescription.clear();
-	commitId = -1;
-	savedCommitId = 0;
 }
 
 void AssFile::LoadDefault(bool defline) {
@@ -747,7 +773,7 @@ int AssFile::Commit(wxString desc, int type, int amendId, AssEntry *single_line)
 	++commitId;
 	// Allow coalescing only if it's the last change and the file has not been
 	// saved since the last change
-	if (commitId == amendId+1 && RedoStack.empty() && savedCommitId != commitId) {
+	if (commitId == amendId+1 && RedoStack.empty() && savedCommitId+1 != commitId && autosavedCommitId+1 != commitId) {
 		// If only one line changed just modify it instead of copying the file
 		if (single_line) {
 			entryIter this_it = Line.begin(), undo_it = UndoStack.back().Line.begin();

aegisub/src/ass_file.h

@@ -71,6 +71,8 @@ class AssFile {
 	int commitId;
 	/// Last saved version of this file
 	int savedCommitId;
+	/// Last autosaved version of this file
+	int autosavedCommitId;
 
 	/// A set of changes has been committed to the file (AssFile::CommitType)
 	agi::signal::Signal<int> AnnounceCommit;
@@ -123,12 +125,18 @@ public:
 	/// @param charset Character set of file or empty to autodetect
 	/// @param addToRecent Should the file be added to the MRU list?
 	void Load(const wxString &file,wxString charset="",bool addToRecent=true);
+
 	/// @brief Save to a file
 	/// @param file Path to save to
 	/// @param setfilename Should the filename be changed to the passed path?
 	/// @param addToRecent Should the file be added to the MRU list?
 	/// @param encoding Encoding to use, or empty to let the writer decide (which usually means "App/Save Charset")
 	void Save(wxString file,bool setfilename=false,bool addToRecent=true,const wxString encoding="");
+
+	/// @brief Autosave the file if there have been any chances since the last autosave
+	/// @return File name used or empty if no save was performed
+	wxString AutoSave();
+
 	/// @brief Save to a memory buffer. Used for subtitle providers which support it
 	/// @param[out] dst Destination vector
 	void SaveMemory(std::vector<char> &dst,const wxString encoding="");

aegisub/src/frame_main.cpp

@@ -585,27 +585,9 @@ void FrameMain::OnCloseWindow (wxCloseEvent &event) {
 }
 
 void FrameMain::OnAutoSave(wxTimerEvent &) try {
-	if (context->ass->loaded && context->ass->IsModified()) {
-		wxFileName origfile(context->ass->filename);
-		wxString path = lagi_wxString(OPT_GET("Path/Auto/Save")->GetString());
-		if (path.IsEmpty()) path = origfile.GetPath();
-		wxFileName dstpath(path);
-		if (!dstpath.IsAbsolute()) path = StandardPaths::DecodePathMaybeRelative(path, "?user/");
-		dstpath.AssignDir(path);
-		if (!dstpath.DirExists()) wxMkdir(path);
-
-		wxString name = origfile.GetName();
-		if (name.empty()) {
-			dstpath.SetFullName("Untitled.AUTOSAVE.ass");
-		}
-		else {
-			dstpath.SetFullName(name + ".AUTOSAVE.ass");
-		}
-
-		context->ass->Save(dstpath.GetFullPath(),false,false);
-
-		StatusTimeout(_("File backup saved as \"") + dstpath.GetFullPath() + "\".");
-	}
+	wxString fn = context->ass->AutoSave();
+	if (!fn.empty())
+		StatusTimeout(wxString::Format(_("File backup saved as \"%s\"."), fn));
 }
 catch (const agi::Exception& err) {
 	StatusTimeout(lagi_wxString("Exception when attempting to autosave file: " + err.GetMessage()));