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#include "qnsview.h"
#include "qcocoainputcontext.h"
#include "qcocoanativeinterface.h"
#include "qcocoawindow.h"
#include "qcocoahelpers.h"

#include <Carbon/Carbon.h>

#include <QtCore/QRect>
#include <QtGui/QGuiApplication>
#include <QtGui/QWindow>

QT_BEGIN_NAMESPACE

/*!
    \class QCocoaInputContext
    \brief Cocoa Input context implementation

    Handles input of foreign characters (particularly East Asian)
    languages.

    \section1 Testing

    \list
    \o Select input sources like 'Kotoeri' in Language & Text Preferences
    \o Compile the \a mainwindows/mdi example and open a text window.
    \o In the language bar, switch to 'Hiragana'.
    \o In a text editor control, type the syllable \a 'la'.
       Underlined characters show up, indicating that there is completion
       available. Press the Space key two times. A completion popup occurs
       which shows the options.
    \endlist

    \section1 Interaction

    Input method support in Cocoa uses NSTextInput protorol. Therefore
    almost all functionality is implemented in QNSView.
*/


QCocoaInputContext::QCocoaInputContext()
    : QPlatformInputContext()
    , mWindow(QGuiApplication::focusWindow())
{
    QMetaObject::invokeMethod(this, "connectSignals", Qt::QueuedConnection);
    updateLocale();
}

QCocoaInputContext::~QCocoaInputContext()
{
}

/*!
    \brief Cancels a composition.
*/

void QCocoaInputContext::reset()
{
    QPlatformInputContext::reset();

    if (!mWindow)
        return;

    QCocoaWindow *window = static_cast<QCocoaWindow *>(mWindow->handle());
    QNSView *view = qnsview_cast(window->view());
    if (!view)
        return;

    QMacAutoReleasePool pool;
    if (NSTextInputContext *ctxt = [NSTextInputContext currentInputContext]) {
        [ctxt discardMarkedText];
        [view unmarkText];
    }
}

void QCocoaInputContext::connectSignals()
{
    connect(qApp, SIGNAL(focusObjectChanged(QObject*)), this, SLOT(focusObjectChanged(QObject*)));
    focusObjectChanged(qApp->focusObject());
}

void QCocoaInputContext::focusObjectChanged(QObject *focusObject)
{
    Q_UNUSED(focusObject);
    if (mWindow == QGuiApplication::focusWindow()) {
        if (!mWindow)
            return;

        QCocoaWindow *window = static_cast<QCocoaWindow *>(mWindow->handle());
        if (!window)
            return;
        QNSView *view = qnsview_cast(window->view());
        if (!view)
            return;

        if (NSTextInputContext *ctxt = [NSTextInputContext currentInputContext]) {
            [ctxt discardMarkedText];
            [view cancelComposingText];
        }
    } else {
        mWindow = QGuiApplication::focusWindow();
    }
}

void QCocoaInputContext::updateLocale()
{
    TISInputSourceRef source = TISCopyCurrentKeyboardInputSource();
    CFArrayRef languages = (CFArrayRef) TISGetInputSourceProperty(source, kTISPropertyInputSourceLanguages);
    if (CFArrayGetCount(languages) > 0) {
        CFStringRef langRef = (CFStringRef)CFArrayGetValueAtIndex(languages, 0);
        QString name = QString::fromCFString(langRef);
        QLocale locale(name);
        if (m_locale != locale) {
            m_locale = locale;
            emitLocaleChanged();
        }
    }
    CFRelease(source);
}

QT_END_NAMESPACE