User manual: show a localized version of the manual if it exists

So far we only have Spanish, but it always pays to plan ahead.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

helpers.h

@@ -32,6 +32,7 @@ int parseTemperatureToMkelvin(const QString &text);
 QString get_dive_date_string(timestamp_t when);
 QString get_short_dive_date_string(timestamp_t when);
 QString get_trip_date_string(timestamp_t when, int nr);
+QString uiLanguage(QLocale *callerLoc);
 
 #define M_OR_FT(_m, _f) ((prefs.units.length == units::METERS) ? ((_m) * 1000) : (feet_to_mm(_f)))
 

qt-gui.cpp

@@ -76,9 +76,36 @@ void init_qt(int *argcp, char ***argvp)
 	application = new QApplication(*argcp, *argvp);
 }
 
+QString uiLanguage(QLocale *callerLoc)
+{
+	QSettings s;
+	s.beginGroup("Language");
+	QLocale loc;
+
+	if (!s.value("UseSystemLanguage", true).toBool()) {
+		loc = QLocale(s.value("UiLanguage", QLocale().uiLanguages().first()).toString());
+	}
+
+	QString uiLang = loc.uiLanguages().first();
+	s.endGroup();
+
+	// there's a stupid Qt bug on MacOS where uiLanguages doesn't give us the country info
+	if (!uiLang.contains('-') && uiLang != loc.bcp47Name()) {
+		QLocale loc2(loc.bcp47Name());
+		loc = loc2;
+		uiLang = loc2.uiLanguages().first();
+	}
+	if (callerLoc)
+		*callerLoc = loc;
+
+	return uiLang;
+}
+
 void init_ui(void)
 {
 	QVariant v;
+	QSettings s;
+
 	// tell Qt to use system proxies
 	// note: on Linux, "system" == "environment variables"
 	QNetworkProxyFactory::setUseSystemConfiguration(true);
@@ -102,24 +129,8 @@ void init_ui(void)
 	QCoreApplication::setApplicationName("Subsurface");
 	// find plugins installed in the application directory (without this SVGs don't work on Windows)
 	QCoreApplication::addLibraryPath(QCoreApplication::applicationDirPath());
-
-	QSettings s;
-	s.beginGroup("Language");
 	QLocale loc;
-
+	QString uiLang = uiLanguage(&loc);
-	if (!s.value("UseSystemLanguage", true).toBool()) {
-		loc = QLocale(s.value("UiLanguage", QLocale().uiLanguages().first()).toString());
-	}
-
-	QString uiLang = loc.uiLanguages().first();
-	s.endGroup();
-
-	// there's a stupid Qt bug on MacOS where uiLanguages doesn't give us the country info
-	if (!uiLang.contains('-') && uiLang != loc.bcp47Name()) {
-		QLocale loc2(loc.bcp47Name());
-		loc = loc2;
-		uiLang = loc2.uiLanguages().first();
-	}
 
 	// we don't have translations for English - if we don't check for this
 	// Qt will proceed to load the second language in preference order - not what we want

qt-ui/usermanual.cpp

@@ -1,10 +1,12 @@
 #include <QDesktopServices>
 #include <QShortcut>
+#include <QFile>
+#include <QDebug>
 
 #include "usermanual.h"
 #include "ui_usermanual.h"
 
-#include "../helpers.h"
+#include "helpers.h"
 
 UserManual::UserManual(QWidget *parent) : QMainWindow(parent),
 	ui(new Ui::UserManual)
@@ -31,7 +33,15 @@ UserManual::UserManual(QWidget *parent) : QMainWindow(parent),
 	ui->webView->page()->setLinkDelegationPolicy(QWebPage::DelegateExternalLinks);
 	QString searchPath = getSubsurfaceDataPath("Documentation");
 	if (searchPath.size()) {
-		QUrl url(searchPath.append("/user-manual.html"));
+		// look for localized versions of the manual first
+		QString lang = uiLanguage(NULL);
+		QString prefix = searchPath.append("/user-manual");
+		QFile manual(prefix + "_" + lang + ".html");
+		if (!manual.exists())
+			manual.setFileName(prefix + "_" + lang.left(2) + ".html");
+		if (!manual.exists())
+			manual.setFileName(prefix + ".html");
+		QUrl url(manual.fileName());
 		ui->webView->setUrl(url);
 	} else {
 		ui->webView->setHtml(tr("Cannot find the Subsurface manual"));