qt: allow user to choose data directory

This adds an introduction screen that is shown when the client is first
started in which the user can choose a data directory.

It is also possible to force the intro screen to appear using command
line argument `-choosedatadir`.

The user is warned that the client will download and store 10Gb of data.
The intro screen shows how much space is available on the device that
contains the chosen directory and warns if this is less than the 10Gb.

To make it possible to translate the introduction dialog, the initialization
sequence is changed so that translations are
loaded before the data directory. This has the by-effect that it is
no longer possible to specify a language in bitcoin.conf inside the data
directory.

1 files changed, 60 insertions, 40 deletions

diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index 76e88b36a7..b0c45d6863 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -15,6 +15,7 @@
 #include "ui_interface.h"
 #include "paymentserver.h"
 #include "splashscreen.h"
+#include "intro.h"
 
 #include <QMessageBox>
 #if QT_VERSION < 0x050000
@@ -24,6 +25,7 @@
 #include <QTimer>
 #include <QTranslator>
 #include <QLibraryInfo>
+#include <QSettings>
 
 #if defined(BITCOIN_NEED_QT_PLUGINS) && !defined(_BITCOIN_QT_PLUGINS_INCLUDED)
 #define _BITCOIN_QT_PLUGINS_INCLUDED
@@ -110,6 +112,46 @@ static void handleRunawayException(std::exception *e)
     exit(1);
 }
 
+/** Set up translations */
+static void initTranslations(QTranslator &qtTranslatorBase, QTranslator &qtTranslator, QTranslator &translatorBase, QTranslator &translator)
+{
+    QSettings settings;
+
+    // Get desired locale (e.g. "de_DE")
+    // 1) System default language
+    QString lang_territory = QLocale::system().name();
+    // 2) Language from QSettings
+    QString lang_territory_qsettings = settings.value("language", "").toString();
+    if(!lang_territory_qsettings.isEmpty())
+        lang_territory = lang_territory_qsettings;
+    // 3) -lang command line argument
+    lang_territory = QString::fromStdString(GetArg("-lang", lang_territory.toStdString()));
+
+    // Convert to "de" only by truncating "_DE"
+    QString lang = lang_territory;
+    lang.truncate(lang_territory.lastIndexOf('_'));
+
+    // Load language files for configured locale:
+    // - First load the translator for the base language, without territory
+    // - Then load the more specific locale translator
+
+    // Load e.g. qt_de.qm
+    if (qtTranslatorBase.load("qt_" + lang, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
+        QApplication::installTranslator(&qtTranslatorBase);
+
+    // Load e.g. qt_de_DE.qm
+    if (qtTranslator.load("qt_" + lang_territory, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
+        QApplication::installTranslator(&qtTranslator);
+
+    // Load e.g. bitcoin_de.qm (shortcut "de" needs to be defined in bitcoin.qrc)
+    if (translatorBase.load(lang, ":/translations/"))
+        QApplication::installTranslator(&translatorBase);
+
+    // Load e.g. bitcoin_de_DE.qm (shortcut "de_DE" needs to be defined in bitcoin.qrc)
+    if (translator.load(lang_territory, ":/translations/"))
+        QApplication::installTranslator(&translator);
+}
+
 #ifndef BITCOIN_QT_TEST
 int main(int argc, char *argv[])
 {
@@ -130,6 +172,22 @@ int main(int argc, char *argv[])
     // Register meta types used for QMetaObject::invokeMethod
     qRegisterMetaType< bool* >();
 
+    // Application identification (must be set before OptionsModel is initialized,
+    // as it is used to locate QSettings)
+    QApplication::setOrganizationName("Bitcoin");
+    QApplication::setOrganizationDomain("bitcoin.org");
+    if (GetBoolArg("-testnet", false)) // Separate UI settings for testnet
+        QApplication::setApplicationName("Bitcoin-Qt-testnet");
+    else
+        QApplication::setApplicationName("Bitcoin-Qt");
+
+    // Now that QSettings are accessible, initialize translations
+    QTranslator qtTranslatorBase, qtTranslator, translatorBase, translator;
+    initTranslations(qtTranslatorBase, qtTranslator, translatorBase, translator);
+
+    // User language is set up: pick a data directory
+    Intro::pickDataDirectory();
+
     // Do this early as we don't want to bother initializing if we are just calling IPC
     // ... but do it after creating app, so QCoreApplication::arguments is initialized:
     if (PaymentServer::ipcSendCommandLine())
@@ -142,53 +200,15 @@ int main(int argc, char *argv[])
     // ... then bitcoin.conf:
     if (!boost::filesystem::is_directory(GetDataDir(false)))
     {
-        // This message can not be translated, as translation is not initialized yet
-        // (which not yet possible because lang=XX can be overridden in bitcoin.conf in the data directory)
-        QMessageBox::critical(0, "Bitcoin",
-                              QString("Error: Specified data directory \"%1\" does not exist.").arg(QString::fromStdString(mapArgs["-datadir"])));
+        QMessageBox::critical(0, QObject::tr("Bitcoin"),
+                              QObject::tr("Error: Specified data directory \"%1\" does not exist.").arg(QString::fromStdString(mapArgs["-datadir"])));
         return 1;
     }
     ReadConfigFile(mapArgs, mapMultiArgs);
 
-    // Application identification (must be set before OptionsModel is initialized,
-    // as it is used to locate QSettings)
-    QApplication::setOrganizationName("Bitcoin");
-    QApplication::setOrganizationDomain("bitcoin.org");
-    if (GetBoolArg("-testnet", false)) // Separate UI settings for testnet
-        QApplication::setApplicationName("Bitcoin-Qt-testnet");
-    else
-        QApplication::setApplicationName("Bitcoin-Qt");
-
     // ... then GUI settings:
     OptionsModel optionsModel;
 
-    // Get desired locale (e.g. "de_DE") from command line or use system locale
-    QString lang_territory = QString::fromStdString(GetArg("-lang", QLocale::system().name().toStdString()));
-    QString lang = lang_territory;
-    // Convert to "de" only by truncating "_DE"
-    lang.truncate(lang_territory.lastIndexOf('_'));
-
-    QTranslator qtTranslatorBase, qtTranslator, translatorBase, translator;
-    // Load language files for configured locale:
-    // - First load the translator for the base language, without territory
-    // - Then load the more specific locale translator
-
-    // Load e.g. qt_de.qm
-    if (qtTranslatorBase.load("qt_" + lang, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
-        app.installTranslator(&qtTranslatorBase);
-
-    // Load e.g. qt_de_DE.qm
-    if (qtTranslator.load("qt_" + lang_territory, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
-        app.installTranslator(&qtTranslator);
-
-    // Load e.g. bitcoin_de.qm (shortcut "de" needs to be defined in bitcoin.qrc)
-    if (translatorBase.load(lang, ":/translations/"))
-        app.installTranslator(&translatorBase);
-
-    // Load e.g. bitcoin_de_DE.qm (shortcut "de_DE" needs to be defined in bitcoin.qrc)
-    if (translator.load(lang_territory, ":/translations/"))
-        app.installTranslator(&translator);
-
     // Subscribe to global signals from core
     uiInterface.ThreadSafeMessageBox.connect(ThreadSafeMessageBox);
     uiInterface.ThreadSafeAskFee.connect(ThreadSafeAskFee);