Set default locale on saved choice or environment

Guess the default locale from the envinroment (GetLocaleInfo() on Windows and
the setlocale() on Linux/Unix) or from the saved settings for mmg.

src/common/translation.cpp

@@ -47,8 +47,10 @@ translation_c::translation_c(const std::string &unix_locale,
 void
 translation_c::initialize_available_translations() {
   ms_available_translations.clear();
+#if defined(HAVE_LIBINTL_H)
   ms_available_translations.push_back(translation_c("en_US", "english", "English", "English"));
   ms_available_translations.push_back(translation_c("de_DE", "german",  "German",  "Deutsch"));
+#endif
 }
 
 int
@@ -67,6 +69,47 @@ translation_c::look_up_translation(const std::string &locale) {
   return -1;
 }
 
+std::string
+translation_c::get_default_ui_locale() {
+  std::string locale;
+
+#if defined(HAVE_LIBINTL_H)
+# if defined(SYS_WINDOWS)
+  char *data;
+  int len = GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_SENGLANGUAGE, NULL, 0);
+  if (0 < len) {
+    data = (char *)safemalloc(len);
+    memset(data, 0, len);
+    if (0 != GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_SENGLANGUAGE, data, len))
+      locale = data;
+    safefree(data);
+  }
+
+# else  // SYS_WINDOWS
+
+  char *data = setlocale(LC_MESSAGES, NULL);
+  if (NULL != data) {
+    std::string previous_locale = data;
+    setlocale(LC_MESSAGES, "");
+    data = setlocale(LC_MESSAGES, NULL);
+
+    if (NULL != data) {
+      std::vector<std::string> parts = split(data, ".");
+      locale                         = parts[0];
+    }
+
+    setlocale(LC_MESSAGES, previous_locale.c_str());
+  }
+
+# endif // SYS_WINDOWS
+#endif  // HAVE_LIBINTL_H
+
+  if (!locale.empty() && (-1 == look_up_translation(locale)))
+    locale = "";
+
+  return locale;
+}
+
 std::string
 translation_c::get_locale() {
 #if defined(SYS_WINDOWS)
@@ -84,25 +127,13 @@ init_locales(std::string locale) {
 
   string locale_dir;
 
-  if (!locale.empty()) {
-    int idx = translation_c::look_up_translation(locale);
-    if (-1 == idx)
-      locale = "";
-  }
+  if (-1 == translation_c::look_up_translation(locale))
+    locale = "";
+
+  if (locale.empty())
+    locale = translation_c::get_default_ui_locale();
 
 # if defined(SYS_WINDOWS)
-  if (locale.empty()) {
-    char *data;
-    int len = GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_SENGLANGUAGE, NULL, 0);
-    if (0 < len) {
-      data = (char *)safemalloc(len);
-      memset(data, 0, len);
-      if (0 != GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_SENGLANGUAGE, data, len))
-        locale = data;
-      safefree(data);
-    }
-  }
-
   if (!locale.empty()) {
     // The Windows system headers define LC_MESSAGES but
     // Windows itself doesn't know it and treats "set_locale(LC_MESSAGES, ...)"

src/common/translation.h

@@ -35,6 +35,7 @@ public:
 
   static void initialize_available_translations();
   static int look_up_translation(const std::string &locale);
+  static std::string get_default_ui_locale();
 };
 
 void MTX_DLL_API init_locales(std::string locale = "");

src/mmg/mmg.cpp

@@ -2160,6 +2160,25 @@ BEGIN_EVENT_TABLE(mmg_dialog, wxFrame)
   EVT_CLOSE(mmg_dialog::on_close)
 END_EVENT_TABLE();
 
+void
+mmg_app::init_ui_locale(wxConfigBase *cfg) {
+  wxString w_locale;
+  std::string locale;
+
+  translation_c::initialize_available_translations();
+
+  cfg->SetPath(wxT("/GUI"));
+  if (cfg->Read(wxT("ui_locale"), &w_locale)) {
+    locale = wxMB(w_locale);
+    if (-1 == translation_c::look_up_translation(locale))
+      locale = "";
+  }
+
+  m_ui_locale = locale;
+
+  init_locales(locale);
+}
+
 bool
 mmg_app::OnInit() {
   wxConfigBase *cfg;
@@ -2167,14 +2186,15 @@ mmg_app::OnInit() {
   wxString k, v;
   int index;
 
+  cfg = new wxConfig(wxT("mkvmergeGUI"));
+  wxConfigBase::Set(cfg);
+
   init_stdio();
-  init_locales();
+  init_ui_locale(cfg);
   mm_file_io_c::setup();
   cc_local_utf8 = utf8_init("");
   xml_element_map_init();
 
-  cfg = new wxConfig(wxT("mkvmergeGUI"));
-  wxConfigBase::Set(cfg);
   cfg->SetPath(wxT("/GUI"));
   cfg->Read(wxT("last_directory"), &last_open_dir, wxEmptyString);
   for (i = 0; i < 4; i++) {

src/mmg/mmg.h

@@ -19,9 +19,10 @@
 
 #include "os.h"
 
-#include "wx/string.h"
 #include "wx/app.h"
 #include "wx/combobox.h"
+#include "wx/config.h"
+#include "wx/string.h"
 
 #include "ebml/EbmlUnicodeString.h"
 
@@ -179,9 +180,12 @@ wxString format_tooltip(const wxString &s);
 #endif
 
 class mmg_app: public wxApp {
+public:
+  std::string m_ui_locale;
 public:
   virtual bool OnInit();
   virtual int OnExit();
+  virtual void init_ui_locale(wxConfigBase *cfg);
 };
 
 extern mmg_app *app;