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#include "q3accel.h"

#include "q3signal.h"

#include "qapplication.h"

#include "qwidget.h"

#include "q3ptrlist.h"

#include "qwhatsthis.h"

#include "qpointer.h"

#include "qstatusbar.h"

#include "qdockwidget.h"

#include "qevent.h"

#include "qkeysequence.h"

#include "private/qapplication_p.h"

QT_BEGIN_NAMESPACE

using namespace Qt;

/*!

    \class Q3Accel

    \brief The Q3Accel class handles keyboard accelerator and shortcut keys.

    \compat

    A keyboard accelerator triggers an action when a certain key

    combination is pressed. The accelerator handles all keyboard

    activity for all the children of one top-level widget, so it is

    not affected by the keyboard focus.

    In most cases, you will not need to use this class directly. Use

    the QAction class to create actions with accelerators that can be

    used in both menus and toolbars. If you're only interested in

    menus use Q3MenuData::insertItem() or Q3MenuData::setAccel() to make

    accelerators for operations that are also available on menus. Many

    widgets automatically generate accelerators, such as QAbstractButton,

    QGroupBox, QLabel (with QLabel::setBuddy()), QMenuBar, and QTabBar.

    Example:

    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 0

    A Q3Accel contains a list of accelerator items that can be

    manipulated using insertItem(), removeItem(), clear(), key() and

    findKey().

    Each accelerator item consists of an identifier and a \l

    QKeySequence. A single key sequence consists of a keyboard code

    combined with modifiers (Qt::SHIFT, Qt::CTRL, Qt::ALT, or

    Qt::UNICODE_ACCEL). For example, Qt::CTRL + Qt::Key_P could be a shortcut

    for printing a document. As an alternative, use Qt::UNICODE_ACCEL with the

    unicode code point of the character. For example, Qt::UNICODE_ACCEL

    + 'A' gives the same accelerator as Qt::Key_A.

    When an accelerator key is pressed, the accelerator sends out the

    signal activated() with a number that identifies this particular

    accelerator item. Accelerator items can also be individually

    connected, so that two different keys will activate two different

    slots (see connectItem() and disconnectItem()).

    The activated() signal is \e not emitted when two or more

    accelerators match the same key.  Instead, the first matching

    accelerator sends out the activatedAmbiguously() signal. By

    pressing the key multiple times, users can navigate between all

    matching accelerators. Some standard controls like QPushButton and

    QCheckBox connect the activatedAmbiguously() signal to the

    harmless setFocus() slot, whereas activated() is connected to a

    slot invoking the button's action. Most controls, like QLabel and

    QTabBar, treat activated() and activatedAmbiguously() as

    equivalent.

    Use setEnabled() to enable or disable all the items in an

    accelerator, or setItemEnabled() to enable or disable individual

    items. An item is active only when both the Q3Accel and the item

    itself are enabled.

    The function setWhatsThis() specifies a help text that appears

    when the user presses an accelerator key in What's This mode.

    The accelerator will be deleted when \e parent is deleted,

    and will consume relevant key events until then.

    Please note that the accelerator

    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 1

    can be triggered with both the 'M' key, and with Shift+M,

    unless a second accelerator is defined for the Shift+M

    combination.

    Example:

    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 2

    \sa QKeyEvent QWidget::keyPressEvent()

    QAbstractButton::setAccel() QLabel::setBuddy() QKeySequence

*/

struct Q3AccelItem {                                // internal accelerator item

    Q3AccelItem(const QKeySequence &k, int i)

        { key=k; id=i; enabled=true; signal=0; }

   ~Q3AccelItem()               { delete signal; }

    int id;

    QKeySequence key;

    bool enabled;

    Q3Signal *signal;

    QString whatsthis;

};

typedef Q3PtrList<Q3AccelItem> Q3AccelList; // internal accelerator list

class Q3AccelPrivate {

public:

    Q3AccelPrivate(Q3Accel* p);

    ~Q3AccelPrivate();

    Q3AccelList aitems;

    bool enabled;

    QPointer<QWidget> watch;

    bool ignorewhatsthis;

    Q3Accel* parent;

    void activate(Q3AccelItem* item);

    void activateAmbiguously(Q3AccelItem* item);

};

class Q3AccelManager {

public:

    static Q3AccelManager* self() { return self_ptr ? self_ptr : new Q3AccelManager; }

    void registerAccel(Q3AccelPrivate* a) { accels.append(a); }

    void unregisterAccel(Q3AccelPrivate* a) { accels.removeRef(a); if (accels.isEmpty()) delete this; }

    bool tryAccelEvent(QWidget* w, QKeyEvent* e);

    bool dispatchAccelEvent(QWidget* w, QKeyEvent* e);

    bool tryComposeUnicode(QWidget* w, QKeyEvent* e);

private:

    Q3AccelManager()

        : currentState(QKeySequence::NoMatch), clash(-1), metaComposeUnicode(false),composedUnicode(0)

        { setFuncPtr(); self_ptr = this; }

    ~Q3AccelManager() { self_ptr = 0; }

    void setFuncPtr();

    bool correctSubWindow(QWidget *w, Q3AccelPrivate* d);

    QKeySequence::SequenceMatch match(QKeyEvent* e, Q3AccelItem* item, QKeySequence& temp);

    int translateModifiers(ButtonState state);

    Q3PtrList<Q3AccelPrivate> accels;

    static Q3AccelManager* self_ptr;

    QKeySequence::SequenceMatch currentState;

    QKeySequence intermediate;

    int clash;

    bool metaComposeUnicode;

    int composedUnicode;

};

Q3AccelManager* Q3AccelManager::self_ptr = 0;

bool Q_COMPAT_EXPORT qt_tryAccelEvent(QWidget* w, QKeyEvent*  e){

    return Q3AccelManager::self()->tryAccelEvent(w, e);

}

bool Q_COMPAT_EXPORT qt_dispatchAccelEvent(QWidget* w, QKeyEvent*  e){

    return Q3AccelManager::self()->dispatchAccelEvent(w, e);

}

bool Q_COMPAT_EXPORT qt_tryComposeUnicode(QWidget* w, QKeyEvent*  e){

    return Q3AccelManager::self()->tryComposeUnicode(w, e);

}

void Q3AccelManager::setFuncPtr() {

    if (qApp->d_func()->qt_compat_used)

        return;

    QApplicationPrivate *data = static_cast<QApplicationPrivate*>(qApp->d_ptr.data());

    data->qt_tryAccelEvent = qt_tryAccelEvent;

    data->qt_tryComposeUnicode = qt_tryComposeUnicode;

    data->qt_dispatchAccelEvent = qt_dispatchAccelEvent;

    data->qt_compat_used = true;

}

#ifdef Q_WS_MAC

static bool qt_accel_no_shortcuts = true;

#else

static bool qt_accel_no_shortcuts = false;

#endif

void Q_COMPAT_EXPORT qt_set_accel_auto_shortcuts(bool b) { qt_accel_no_shortcuts = b; }

/*

    \internal

    Returns true if the accel is in the current subwindow, else false.

*/

bool Q3AccelManager::correctSubWindow(QWidget* w, Q3AccelPrivate* d) {

#if !defined (Q_OS_MACX)

     if (!d->watch || !d->watch->isVisible() || !d->watch->isEnabled())

#else

    if (!d->watch || (!d->watch->isVisible() && !d->watch->inherits("QMenuBar")) || !d->watch->isEnabled())

#endif

        return false;

    QWidget* tlw = w->window();

    QWidget* wtlw = d->watch->window();

    /* if we live in a floating dock window, keep our parent's

     * accelerators working */

#ifndef QT_NO_MAINWINDOW

    if ((tlw->windowType() == Qt::Dialog) && tlw->parentWidget() && qobject_cast<QDockWidget*>(tlw))

        return tlw->parentWidget()->window() == wtlw;

    if (wtlw  != tlw)

        return false;

#endif

    /* if we live in a MDI subwindow, ignore the event if we are

       not the active document window */

    QWidget* sw = d->watch;

    while (sw && sw->windowType() != Qt::SubWindow)

        sw = sw->parentWidget(true);

    if (sw)  { // we are in a subwindow indeed

        QWidget* fw = w;

        while (fw && fw != sw)

            fw = fw->parentWidget(true);

        if (fw != sw) // focus widget not in our subwindow

            return false;

    }

    return true;

}

inline int Q3AccelManager::translateModifiers(ButtonState state)

{

    int result = 0;

    if (state & ShiftButton)

        result |= SHIFT;

    if (state & ControlButton)

        result |= CTRL;

    if (state & MetaButton)

        result |= META;

    if (state & AltButton)

        result |= ALT;

    return result;

}

/*

    \internal

    Matches the current intermediate key sequence + the latest

    keyevent, with and AccelItem. Returns Identical,

    PartialMatch or NoMatch, and fills \a temp with the

    resulting key sequence.

*/

QKeySequence::SequenceMatch Q3AccelManager::match(QKeyEvent *e, Q3AccelItem* item, QKeySequence& temp)

{

    QKeySequence::SequenceMatch result = QKeySequence::NoMatch;

    int index = intermediate.count();

    temp = intermediate;

    int modifier = translateModifiers(e->state());

    if (e->key() && e->key() != Key_unknown) {

        int key = e->key()  | modifier;

        if (e->key() == Key_BackTab) {

            /*

            In QApplication, we map shift+tab to shift+backtab.

            This code here reverts the mapping in a way that keeps

            backtab and shift+tab accelerators working, in that

            order, meaning backtab has priority.*/

            key &= ~SHIFT;

            temp.setKey(key, index);

            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))

                return result;

            if (e->state() & ShiftButton)

                key |= SHIFT;

            key = Key_Tab | (key & MODIFIER_MASK);

            temp.setKey(key, index);

            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))

                return result;

        } else {

            temp.setKey(key, index);

            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))

                return result;

        }

        if (key == Key_BackTab) {

            if (e->state() & ShiftButton)

                key |= SHIFT;

            temp.setKey(key, index);

            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))

                return result;

        }

    }

    if (!e->text().isEmpty()) {

        temp.setKey((int)e->text()[0].unicode() | UNICODE_ACCEL | modifier, index);

        result = temp.matches(item->key);

    }

    return result;

}

bool Q3AccelManager::tryAccelEvent(QWidget* w, QKeyEvent* e)

{

    if (QKeySequence::NoMatch == currentState) {

        e->t = QEvent::AccelOverride;

        e->ignore();

        QApplication::sendSpontaneousEvent(w, e);

        if (e->isAccepted())

            return false;

    }

    e->t = QEvent::Accel;

    e->ignore();

    QApplication::sendSpontaneousEvent(w, e);

    return e->isAccepted();

}

bool Q3AccelManager::tryComposeUnicode(QWidget* w, QKeyEvent* e)

{

    if (metaComposeUnicode) {

        int value = e->key() - Key_0;

        // Ignore acceloverrides so we don't trigger

        // accels on keypad when Meta compose is on

        if ((e->type() == QEvent::AccelOverride) &&

             (e->state() == Qt::Keypad + Qt::MetaButton)) {

            e->accept();

        // Meta compose start/continue

        } else if ((e->type() == QEvent::KeyPress) &&

             (e->state() == Qt::Keypad + Qt::MetaButton)) {

            if (value >= 0 && value <= 9) {

                composedUnicode *= 10;

                composedUnicode += value;

                return true;

            } else {

                // Composing interrupted, dispatch!

                if (composedUnicode) {

                    QChar ch(composedUnicode);

                    QString s(ch);

                    QKeyEvent kep(QEvent::KeyPress, 0, ch.row() ? 0 : ch.cell(), 0, s);

                    QKeyEvent ker(QEvent::KeyRelease, 0, ch.row() ? 0 : ch.cell(), 0, s);

                    QApplication::sendEvent(w, &kep);

                    QApplication::sendEvent(w, &ker);

                }

                composedUnicode = 0;

                return true;

            }

        // Meta compose end, dispatch

        } else if ((e->type() == QEvent::KeyRelease) &&

                    (e->key() == Key_Meta) &&

                    (composedUnicode != 0)) {

            if ((composedUnicode > 0) &&

                 (composedUnicode < 0xFFFE)) {

                QChar ch(composedUnicode);

                QString s(ch);

                QKeyEvent kep(QEvent::KeyPress, 0, ch.row() ? 0 : ch.cell(), 0, s);

                QKeyEvent ker(QEvent::KeyRelease, 0, ch.row() ? 0 : ch.cell(), 0, s);

                QApplication::sendEvent(w, &kep);

                QApplication::sendEvent(w, &ker);

            }

            composedUnicode = 0;

            return true;

        }

    }

    return false;

}

/*

    \internal

    Checks for possible accelerators, if no widget

    ate the keypres, or we are in the middle of a

    partial key sequence.

*/

bool Q3AccelManager::dispatchAccelEvent(QWidget* w, QKeyEvent* e)

{

#ifndef QT_NO_STATUSBAR

    // Needs to be declared and used here because of "goto doclash"

    QStatusBar* mainStatusBar = 0;

#endif

    // Modifiers can NOT be accelerators...

    if (e->key() >= Key_Shift &&

         e->key() <= Key_Alt)

         return false;

    QKeySequence::SequenceMatch result = QKeySequence::NoMatch;

    QKeySequence tocheck, partial;

    Q3AccelPrivate* accel = 0;

    Q3AccelItem* item = 0;

    Q3AccelPrivate* firstaccel = 0;

    Q3AccelItem* firstitem = 0;

    Q3AccelPrivate* lastaccel = 0;

    Q3AccelItem* lastitem = 0;

    QKeyEvent pe = *e;

    int n = -1;

    int hasShift = (e->state()&Qt::ShiftButton)?1:0;

    bool identicalDisabled = false;

    bool matchFound = false;

    do {

        accel = accels.first();

        matchFound = false;

        while (accel) {

            if (correctSubWindow(w, accel)) {

                if (accel->enabled) {

                    item = accel->aitems.last();

                    while(item) {

                        if (QKeySequence::Identical == (result = match(&pe, item, tocheck))) {

                            if (item->enabled) {

                                if (!firstaccel) {

                                    firstaccel = accel;

                                    firstitem = item;

                                }

                                lastaccel = accel;

                                lastitem = item;

                                n++;

                                matchFound = true;

                                if (n > QMAX(clash,0))

                                    goto doclash;

                            } else {

                                identicalDisabled = true;

                            }

                        }

                        if (item->enabled && QKeySequence::PartialMatch == result) {

                            partial = tocheck;

                            matchFound = true;

                        }

                        item = accel->aitems.prev();

                    }

                } else {

                    item = accel->aitems.last();

                    while(item) {

                        if (QKeySequence::Identical == match(&pe, item, tocheck))

                            identicalDisabled = true;

                        item = accel->aitems.prev();

                    }

                }

            }

            accel = accels.next();

        }

        pe = QKeyEvent(QEvent::Accel, pe.key(), pe.ascii(), pe.state()&~Qt::ShiftButton, pe.text());

    } while (hasShift-- && !matchFound && !identicalDisabled);

#ifndef QT_NO_STATUSBAR

    mainStatusBar = (QStatusBar*) w->window()->child(0, "QStatusBar");

#endif

    if (n < 0) { // no match found

        currentState = partial.count() ? QKeySequence::PartialMatch : QKeySequence::NoMatch;

#ifndef QT_NO_STATUSBAR

        // Only display message if we are, or were, in a partial match

        if (mainStatusBar && (QKeySequence::PartialMatch == currentState || intermediate.count())) {

            if (currentState == QKeySequence::PartialMatch) {

                mainStatusBar->showMessage((QString)partial + QLatin1String(", ..."));

            } else if (!identicalDisabled) {

                QString message = Q3Accel::tr("%1, %2 not defined").

                    arg((QString)intermediate).

                    arg(QKeySequence::encodeString(e->key() | translateModifiers(e->state())));

                mainStatusBar->showMessage(message, 2000);

                // Since we're a NoMatch, reset the clash count

                clash = -1;

            } else {

            	mainStatusBar->clearMessage();

            }

        }

#endif

        bool eatKey = (QKeySequence::PartialMatch == currentState || intermediate.count());

        intermediate = partial;

        if (eatKey)

            e->accept();

        return eatKey;

    } else if (n == 0) { // found exactly one match

        clash = -1; // reset

#ifndef QT_NO_STATUSBAR

        if (currentState == QKeySequence::PartialMatch && mainStatusBar)

                mainStatusBar->clearMessage();

#endif

        currentState = QKeySequence::NoMatch; // Free sequence keylock

        intermediate = QKeySequence();

        lastaccel->activate(lastitem);

        e->accept();

        return true;

    }

 doclash: // found more than one match

#ifndef QT_NO_STATUSBAR

    if (!mainStatusBar) // if "goto doclash", we need to get status bar again.

        mainStatusBar = (QStatusBar*) w->window()->child(0, "QStatusBar");

#endif

    QString message = Q3Accel::tr("Ambiguous %1 not handled").arg((QString)tocheck);

    if (clash >= 0 && n > clash) { // pick next  match

        intermediate = QKeySequence();

        currentState = QKeySequence::NoMatch; // Free sequence keylock

        clash++;

#ifndef QT_NO_STATUSBAR

        if (mainStatusBar &&

             !lastitem->signal &&

             !(lastaccel->parent->receivers(SIGNAL(activatedAmbiguously(int)))))

            mainStatusBar->showMessage(message, 2000);

#endif

        lastaccel->activateAmbiguously(lastitem);