Set language to OS input language when moving cursor

Instead of setting language from context when moving the cursor, set
it to the OS input language. This behavior will probably need to be
controlled by a preference, since not everybody changes keyboard
mapping when changing language.

This required to move BufferView::setCursorLanguage to
Cursor::setLanguageFromInput().

src/BufferView.cpp

@@ -2739,17 +2739,6 @@ Cursor const & BufferView::cursor() const
 }
 
 
-void BufferView::setCursorLanguage(std::string const & code)
-{
-	Language const * lang = languages.getFromCode(code, buffer_.getLanguages());
-	if (lang) {
-		d->cursor_.current_font.setLanguage(lang);
-		d->cursor_.real_current_font.setLanguage(lang);
-	} else
-		LYXERR0("setCursorLanguage: unknown language code " << code);
-}
-
-
 bool BufferView::singleParUpdate()
 {
 	Text & buftext = buffer_.text();

src/BufferView.h

@@ -267,12 +267,6 @@ public:
 	/// sets cursor.
 	/// This is used when handling LFUN_MOUSE_PRESS.
 	bool mouseSetCursor(Cursor & cur, bool select = false);
-	/// Set the cursor language from language code.
-	/* Considers first exact math with the codes used in the document,
-	 * then approximate match among the same list, and finally exact
-	 * or partial match with the whole list of languages.
-	 */
-	void setCursorLanguage(std::string const & code);
 
 	/// sets the selection.
 	/* When \c backwards == false, set anchor

src/Cursor.cpp

@@ -22,6 +22,7 @@
 #include "DispatchResult.h"
 #include "FuncCode.h"
 #include "FuncRequest.h"
+#include "Language.h"
 #include "Layout.h"
 #include "LyXAction.h"
 #include "LyXRC.h"
@@ -51,6 +52,8 @@
 #include "mathed/MathFactory.h"
 #include "mathed/InsetMathMacro.h"
 
+#include "frontends/Application.h"
+
 #include <sstream>
 #include <limits>
 #include <map>
@@ -2396,6 +2399,18 @@ bool notifyCursorLeavesOrEnters(Cursor const & old, Cursor & cur)
 }
 
 
+void Cursor::setLanguageFromInput()
+{
+	string const & code = theApp()->inputLanguageCode();
+	Language const * lang = languages.getFromCode(code, buffer()->getLanguages());
+	if (lang) {
+		current_font.setLanguage(lang);
+		real_current_font.setLanguage(lang);
+	} else
+		LYXERR0("setLanguageFromCode: unknown language code " << code);
+}
+
+
 void Cursor::setCurrentFont()
 {
 	CursorSlice const & cs = innerTextSlice();
@@ -2429,6 +2444,9 @@ void Cursor::setCurrentFont()
 	current_font = par.getFontSettings(bufparams, cpos);
 	real_current_font = tm.displayFont(cpit, cpos);
 
+	// set language to input language
+	setLanguageFromInput();
+
 	// special case for paragraph end
 	if (cs.pos() == lastpos()
 	    && tm.isRTLBoundary(cpit, cs.pos())

src/Cursor.h

@@ -279,7 +279,13 @@ public:
 	/// get the resut of the last dispatch
 	DispatchResult const & result() const;
 
-	///
+	/// Set the cursor language from current input method language
+	/* Considers first exact math with the codes used in the document,
+	 * then approximate match among the same list, and finally exact
+	 * or partial match with the whole list of languages.
+	 */
+	void setLanguageFromInput();
+	/// Set the current font of the cursor from its location. 
 	void setCurrentFont();
 
 	/**

src/Language.cpp

@@ -390,7 +390,7 @@ Match match(string const & code, Language const & lang)
 	if ((code.size() == 2) && (langcode.size() > 2)
 		&& (code + '_' == langcode.substr(0, 3)))
 		return ApproximateMatch;
- 	if (code.substr(0,2) == langcode.substr(0,2))
+	if (code.substr(0,2) == langcode.substr(0,2))
 		return VeryApproximateMatch;
 	return NoMatch;
 }

src/frontends/qt4/GuiApplication.cpp

@@ -2129,7 +2129,7 @@ string GuiApplication::inputLanguageCode() const
 	QLocale loc = inputMethod()->locale();
 #endif
 	//LYXERR0("input lang = " << fromqstr(loc.name()));
-	return fromqstr(loc.name());
+	return loc.name() == "C" ? "en_US" : fromqstr(loc.name());
 }
 
 
@@ -2137,7 +2137,7 @@ void GuiApplication::onLocaleChanged()
 {
 	//LYXERR0("Change language to " << inputLanguage()->lang());
 	if (currentView() && currentView()->currentBufferView())
-		currentView()->currentBufferView()->setCursorLanguage(inputLanguageCode());
+		currentView()->currentBufferView()->cursor().setLanguageFromInput();
 }
 
 
@@ -2749,7 +2749,7 @@ bool GuiApplication::event(QEvent * e)
 	case QEvent::KeyboardLayoutChange:
 		//LYXERR0("keyboard change");
 		if (currentView() && currentView()->currentBufferView())
-			currentView()->currentBufferView()->setCursorLanguage(inputLanguageCode());
+			currentView()->currentBufferView()->cursor().setLanguageFromInput();
 		e->accept();
 		return true;
 #endif