Default to the language selected in the installer

packages/win_installer/aegisub3.iss

@@ -80,8 +80,10 @@ end;
 procedure CurStepChanged(CurStep: TSetupStep);
 begin
   CurStepChangedMigration(CurStep);
+
+  if CurStep = ssPostInstall then
+  begin
+    SaveStringToFile(ExpandConstant('{app}\installer_config.json'), ExpandConstant('{{"App": {{"Language": "{language}"}}'), False);
+  end;
 end;
 
-
-
-

packages/win_installer/fragment_mainprogram.iss

@@ -52,4 +52,3 @@ Root: HKLM; Subkey: "SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\aegisub
 
 [Run]
 Filename: {app}\aegisub{#ARCH}.exe; Description: {cm:LaunchProgram,Aegisub}; Flags: nowait postinstall skipifsilent
-

src/aegisublocale.cpp

@@ -34,6 +34,7 @@
 
 #include "aegisublocale.h"
 
+#include "compat.h"
 #include "options.h"
 #include "utils.h"
 
@@ -58,9 +59,9 @@ wxTranslations *AegisubLocale::GetTranslations() {
 	return translations;
 }
 
-void AegisubLocale::Init(wxString const& language) {
+void AegisubLocale::Init(std::string const& language) {
 	wxTranslations *translations = GetTranslations();
-	translations->SetLanguage(language);
+	translations->SetLanguage(to_wx(language));
 	translations->AddCatalog(AEGISUB_CATALOG);
 	translations->AddStdCatalog();
 
@@ -69,17 +70,22 @@ void AegisubLocale::Init(wxString const& language) {
 	active_language = language;
 }
 
-wxString AegisubLocale::PickLanguage() {
-	if (!active_language) {
+bool AegisubLocale::HasLanguage(std::string const& language) {
+	auto langs = GetTranslations()->GetAvailableTranslations(AEGISUB_CATALOG);
+	return find(langs.begin(), langs.end(), to_wx(language)) != end(langs);
+}
+
+std::string AegisubLocale::PickLanguage() {
+	if (active_language.empty()) {
 		wxString os_ui_language = GetTranslations()->GetBestTranslation(AEGISUB_CATALOG);
 		if (!os_ui_language.empty())
-			return os_ui_language;
+			return from_wx(os_ui_language);
 	}
 
 	wxArrayString langs = GetTranslations()->GetAvailableTranslations(AEGISUB_CATALOG);
 
 	// No translations available, so don't bother asking the user
-	if (langs.empty() && !active_language)
+	if (langs.empty() && active_language.empty())
 		return "en_US";
 
 	langs.insert(langs.begin(), "en_US");
@@ -107,7 +113,7 @@ wxString AegisubLocale::PickLanguage() {
 	if (dialog.ShowModal() == wxID_OK) {
 		int picked = dialog.GetSelection();
 		if (langs[picked] != active_language)
-			return langs[picked];
+			return from_wx(langs[picked]);
 	}
 
 	return "";

src/aegisublocale.h

@@ -27,19 +27,16 @@
 //
 // Aegisub Project http://www.aegisub.org/
 
-/// @file aegisublocale.h
-/// @see aegisublocale.cpp
-/// @ingroup utility
-///
-
-#include <wx/string.h>
+#include <string>
 
 class wxTranslations;
 
 class AegisubLocale {
-	wxString active_language;
+	std::string active_language;
 	wxTranslations *GetTranslations();
+
 public:
-	void Init(wxString const& language);
-	wxString PickLanguage();
+	void Init(std::string const& language);
+	bool HasLanguage(std::string const& language);
+	std::string PickLanguage();
 };

src/main.cpp

@@ -211,6 +211,18 @@ bool AegisubApp::OnInit() {
 		wxMessageBox("Configuration file is invalid. Error reported:\n" + to_wx(err.GetMessage()), "Error");
 	}
 
+#ifdef _WIN32
+	StartupLog("Load installer configuration");
+	if (OPT_GET("App/First Start")->GetBool()) {
+		try {
+			auto installer_config = agi::io::Open(config::path->Decode("?data/installer_config.json"));
+			config::opt->ConfigNext(*installer_config.get());
+		} catch (agi::fs::FileSystemError const&) {
+			// Not an error obviously as the user may not have used the installer
+		}
+	}
+#endif
+
 	// Init commands.
 	cmd::init_builtin_commands();
 
@@ -245,10 +257,10 @@ bool AegisubApp::OnInit() {
 		StartupLog("Initialize final locale");
 
 		// Set locale
-		wxString lang = to_wx(OPT_GET("App/Language")->GetString());
-		if (!lang) {
+		auto lang = OPT_GET("App/Language")->GetString();
+		if (lang.empty() || (lang != "en_US" && !locale.HasLanguage(lang))) {
 			lang = locale.PickLanguage();
-			OPT_SET("App/Language")->SetString(from_wx(lang));
+			OPT_SET("App/Language")->SetString(lang);
 		}
 		locale.Init(lang);