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#include "qabstractbutton.h"

#include "qabstractitemview.h"

#include "qbuttongroup.h"

#include "qabstractbutton_p.h"

#include "qevent.h"

#include "qpainter.h"

#include "qapplication.h"

#include "qstyle.h"

#include "qaction.h"

#ifndef QT_NO_ACCESSIBILITY

#include "qaccessible.h"

#endif

QT_BEGIN_NAMESPACE

#define AUTO_REPEAT_DELAY  300

#define AUTO_REPEAT_INTERVAL 100

extern bool qt_tab_all_widgets;

/*!

    \class QAbstractButton

    \brief The QAbstractButton class is the abstract base class of

    button widgets, providing functionality common to buttons.

    \ingroup abstractwidgets

    This class implements an \e abstract button.

    Subclasses of this class handle user actions, and specify how the button

    is drawn.

    QAbstractButton provides support for both push buttons and checkable

    (toggle) buttons. Checkable buttons are implemented in the QRadioButton

    and QCheckBox classes. Push buttons are implemented in the

    QPushButton and QToolButton classes; these also provide toggle

    behavior if required.

    Any button can display a label containing text and an icon. setText()

    sets the text; setIcon() sets the icon. If a button is disabled, its label

    is changed to give the button a "disabled" appearance.

    If the button is a text button with a string containing an

    ampersand ('&'), QAbstractButton automatically creates a shortcut

    key. For example:

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

    The \key Alt+C shortcut is assigned to the button, i.e., when the

    user presses \key Alt+C the button will call animateClick(). See

    the \l {QShortcut#mnemonic}{QShortcut} documentation for details

    (to display an actual ampersand, use '&&').

    You can also set a custom shortcut key using the setShortcut()

    function. This is useful mostly for buttons that do not have any

    text, because they have no automatic shortcut.

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

    All of the buttons provided by Qt (QPushButton, QToolButton,

    QCheckBox, and QRadioButton) can display both \l text and \l{icon}{icons}.

    A button can be made the default button in a dialog are provided by

    QPushButton::setDefault() and QPushButton::setAutoDefault().

    QAbstractButton provides most of the states used for buttons:

    \list

    \o isDown() indicates whether the button is \e pressed down.

    \o isChecked() indicates whether the button is \e checked.  Only

    checkable buttons can be checked and unchecked (see below).

    \o isEnabled() indicates whether the button can be pressed by the

    user.

    \o setAutoRepeat() sets whether the button will auto-repeat if the

    user holds it down. \l autoRepeatDelay and \l autoRepeatInterval

    define how auto-repetition is done.

    \o setCheckable() sets whether the button is a toggle button or not.

    \endlist

    The difference between isDown() and isChecked() is as follows.

    When the user clicks a toggle button to check it, the button is first

    \e pressed then released into the \e checked state. When the user

    clicks it again (to uncheck it), the button moves first to the

    \e pressed state, then to the \e unchecked state (isChecked() and

    isDown() are both false).

    QAbstractButton provides four signals:

    \list 1

    \o pressed() is emitted when the left mouse button is pressed while

    the mouse cursor is inside the button.

    \o released() is emitted when the left mouse button is released.

    \o clicked() is emitted when the button is first pressed and then

    released, when the shortcut key is typed, or when click() or

    animateClick() is called.

    \o toggled() is emitted when the state of a toggle button changes.

    \endlist

    To subclass QAbstractButton, you must reimplement at least

    paintEvent() to draw the button's outline and its text or pixmap. It

    is generally advisable to reimplement sizeHint() as well, and

    sometimes hitButton() (to determine whether a button press is within

    the button). For buttons with more than two states (like tri-state

    buttons), you will also have to reimplement checkStateSet() and

    nextCheckState().

    \sa QButtonGroup

*/

QAbstractButtonPrivate::QAbstractButtonPrivate(QSizePolicy::ControlType type)

    :

#ifndef QT_NO_SHORTCUT

    shortcutId(0),

#endif

    checkable(false), checked(false), autoRepeat(false), autoExclusive(false),

    down(false), blockRefresh(false),

#ifndef QT_NO_BUTTONGROUP

    group(0),

#endif

    autoRepeatDelay(AUTO_REPEAT_DELAY),

    autoRepeatInterval(AUTO_REPEAT_INTERVAL),

    controlType(type)

{}

#ifndef QT_NO_BUTTONGROUP

class QButtonGroupPrivate: public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QButtonGroup)

public:

    QButtonGroupPrivate():exclusive(true){}

    QList<QAbstractButton *> buttonList;

    QPointer<QAbstractButton> checkedButton;

    void detectCheckedButton();

    void notifyChecked(QAbstractButton *button);

    bool exclusive;

    QMap<QAbstractButton*, int> mapping;

};

QButtonGroup::QButtonGroup(QObject *parent)

    : QObject(*new QButtonGroupPrivate, parent)

{

}

QButtonGroup::~QButtonGroup()

{

    Q_D(QButtonGroup);

    for (int i = 0; i < d->buttonList.count(); ++i)

        d->buttonList.at(i)->d_func()->group = 0;

}

bool QButtonGroup::exclusive() const

{

    Q_D(const QButtonGroup);

    return d->exclusive;

}

void QButtonGroup::setExclusive(bool exclusive)

{

    Q_D(QButtonGroup);

    d->exclusive = exclusive;

}

// TODO: Qt 5: Merge with addButton(QAbstractButton *button, int id)

void QButtonGroup::addButton(QAbstractButton *button)

{

    addButton(button, -1);

}

void QButtonGroup::addButton(QAbstractButton *button, int id)

{

    Q_D(QButtonGroup);

    if (QButtonGroup *previous = button->d_func()->group)

        previous->removeButton(button);

    button->d_func()->group = this;

    d->buttonList.append(button);

    if (id == -1) {

        QList<int> ids = d->mapping.values();

        if (ids.isEmpty())

           d->mapping[button] = -2;

        else {

            qSort(ids);

            d->mapping[button] = ids.first()-1;

        }

    } else {

        d->mapping[button] = id;

    }

    if (d->exclusive && button->isChecked())

        button->d_func()->notifyChecked();

}

void QButtonGroup::removeButton(QAbstractButton *button)

{

    Q_D(QButtonGroup);

    if (d->checkedButton == button) {

        d->detectCheckedButton();

    }

    if (button->d_func()->group == this) {

        button->d_func()->group = 0;

        d->buttonList.removeAll(button);

        d->mapping.remove(button);

    }

}

QList<QAbstractButton*> QButtonGroup::buttons() const

{

    Q_D(const QButtonGroup);

    return d->buttonList;

}

QAbstractButton *QButtonGroup::checkedButton() const

{

    Q_D(const QButtonGroup);

    return d->checkedButton;

}

QAbstractButton *QButtonGroup::button(int id) const

{

    Q_D(const QButtonGroup);

    return d->mapping.key(id);

}

void QButtonGroup::setId(QAbstractButton *button, int id)

{

    Q_D(QButtonGroup);

    if (button && id != -1)

        d->mapping[button] = id;

}

int QButtonGroup::id(QAbstractButton *button) const

{

    Q_D(const QButtonGroup);

    return d->mapping.value(button, -1);

}

int QButtonGroup::checkedId() const

{

    Q_D(const QButtonGroup);

    return d->mapping.value(d->checkedButton, -1);

}

// detect a checked button other than the current one

void QButtonGroupPrivate::detectCheckedButton()

{

    QAbstractButton *previous = checkedButton;

    checkedButton = 0;

    if (exclusive)

        return;

    for (int i = 0; i < buttonList.count(); i++) {

        if (buttonList.at(i) != previous && buttonList.at(i)->isChecked()) {

            checkedButton = buttonList.at(i);

            return;

        }

    }

}

#endif // QT_NO_BUTTONGROUP

QList<QAbstractButton *>QAbstractButtonPrivate::queryButtonList() const

{

#ifndef QT_NO_BUTTONGROUP

    if (group)

        return group->d_func()->buttonList;

#endif

    QList<QAbstractButton*>candidates = qFindChildren<QAbstractButton *>(parent);

    if (autoExclusive) {

        for (int i = candidates.count() - 1; i >= 0; --i) {

            QAbstractButton *candidate = candidates.at(i);

            if (!candidate->autoExclusive()

#ifndef QT_NO_BUTTONGROUP

                || candidate->group()

#endif

                )

                candidates.removeAt(i);

        }

    }

    return candidates;

}

QAbstractButton *QAbstractButtonPrivate::queryCheckedButton() const

{

#ifndef QT_NO_BUTTONGROUP

    if (group)

        return group->d_func()->checkedButton;

#endif

    Q_Q(const QAbstractButton);

    QList<QAbstractButton *> buttonList = queryButtonList();

    if (!autoExclusive || buttonList.count() == 1) // no group

        return 0;

    for (int i = 0; i < buttonList.count(); ++i) {

        QAbstractButton *b = buttonList.at(i);

        if (b->d_func()->checked && b != q)

            return b;

    }

    return checked  ? const_cast<QAbstractButton *>(q) : 0;

}

void QAbstractButtonPrivate::notifyChecked()

{

#ifndef QT_NO_BUTTONGROUP

    Q_Q(QAbstractButton);

    if (group) {

        QAbstractButton *previous = group->d_func()->checkedButton;

        group->d_func()->checkedButton = q;

        if (group->d_func()->exclusive && previous && previous != q)

            previous->nextCheckState();

    } else

#endif

    if (autoExclusive) {

        if (QAbstractButton *b = queryCheckedButton())

            b->setChecked(false);

    }

}

void QAbstractButtonPrivate::moveFocus(int key)

{

    QList<QAbstractButton *> buttonList = queryButtonList();;

#ifndef QT_NO_BUTTONGROUP

    bool exclusive = group ? group->d_func()->exclusive : autoExclusive;

#else

    bool exclusive = autoExclusive;

#endif

    QWidget *f = QApplication::focusWidget();

    QAbstractButton *fb = qobject_cast<QAbstractButton *>(f);

    if (!fb || !buttonList.contains(fb))

        return;

    QAbstractButton *candidate = 0;

    int bestScore = -1;

    QRect target = f->rect().translated(f->mapToGlobal(QPoint(0,0)));

    QPoint goal = target.center();

    uint focus_flag = qt_tab_all_widgets ? Qt::TabFocus : Qt::StrongFocus;

    for (int i = 0; i < buttonList.count(); ++i) {

        QAbstractButton *button = buttonList.at(i);

        if (button != f && button->window() == f->window() && button->isEnabled() && !button->isHidden() &&

            (autoExclusive || (button->focusPolicy() & focus_flag) == focus_flag)) {

            QRect buttonRect = button->rect().translated(button->mapToGlobal(QPoint(0,0)));

            QPoint p = buttonRect.center();

            //Priority to widgets that overlap on the same coordinate.

            //In that case, the distance in the direction will be used as significant score,

            //take also in account orthogonal distance in case two widget are in the same distance.

            int score;

            if ((buttonRect.x() < target.right() && target.x() < buttonRect.right())

                  && (key == Qt::Key_Up || key == Qt::Key_Down)) {

                //one item's is at the vertical of the other

                score = (qAbs(p.y() - goal.y()) << 16) + qAbs(p.x() - goal.x());

            } else if ((buttonRect.y() < target.bottom() && target.y() < buttonRect.bottom())

                        && (key == Qt::Key_Left || key == Qt::Key_Right) ) {

                //one item's is at the horizontal of the other

                score = (qAbs(p.x() - goal.x()) << 16) + qAbs(p.y() - goal.y());

            } else {

                score = (1 << 30) + (p.y() - goal.y()) * (p.y() - goal.y()) + (p.x() - goal.x()) * (p.x() - goal.x());

            }

            if (score > bestScore && candidate)

                continue;

            switch(key) {

            case Qt::Key_Up:

                if (p.y() < goal.y()) {

                    candidate = button;

                    bestScore = score;

                }

                break;

            case Qt::Key_Down:

                if (p.y() > goal.y()) {

                    candidate = button;

                    bestScore = score;

                }

                break;

            case Qt::Key_Left:

                if (p.x() < goal.x()) {

                    candidate = button;

                    bestScore = score;

                }

                break;

            case Qt::Key_Right:

                if (p.x() > goal.x()) {

                    candidate = button;

                    bestScore = score;

                }

                break;

            }

        }

    }

    if (exclusive

#ifdef QT_KEYPAD_NAVIGATION

        && !QApplication::keypadNavigationEnabled()

#endif

        && candidate

        && fb->d_func()->checked

        && candidate->d_func()->checkable)

        candidate->click();

    if (candidate) {

        if (key == Qt::Key_Up || key == Qt::Key_Left)

            candidate->setFocus(Qt::BacktabFocusReason);

        else

            candidate->setFocus(Qt::TabFocusReason);

    }

}

void QAbstractButtonPrivate::fixFocusPolicy()

{

    Q_Q(QAbstractButton);

#ifndef QT_NO_BUTTONGROUP

    if (!group && !autoExclusive)

#else

    if (!autoExclusive)

#endif

        return;

    QList<QAbstractButton *> buttonList = queryButtonList();

    for (int i = 0; i < buttonList.count(); ++i) {

        QAbstractButton *b = buttonList.at(i);

        if (!b->isCheckable())

            continue;

        b->setFocusPolicy((Qt::FocusPolicy) ((b == q || !q->isCheckable())

                                         ? (b->focusPolicy() | Qt::TabFocus)

                                         :  (b->focusPolicy() & ~Qt::TabFocus)));

    }

}

void QAbstractButtonPrivate::init()

{

    Q_Q(QAbstractButton);

    q->setFocusPolicy(Qt::FocusPolicy(q->style()->styleHint(QStyle::SH_Button_FocusPolicy)));

    q->setSizePolicy(QSizePolicy(QSizePolicy::Minimum, QSizePolicy::Fixed, controlType));

    q->setAttribute(Qt::WA_WState_OwnSizePolicy, false);

    q->setForegroundRole(QPalette::ButtonText);

    q->setBackgroundRole(QPalette::Button);

}

void QAbstractButtonPrivate::refresh()

{

    Q_Q(QAbstractButton);

    if (blockRefresh)

        return;

    q->update();

#ifndef QT_NO_ACCESSIBILITY

    QAccessible::updateAccessibility(q, 0, QAccessible::StateChanged);

#endif

}

void QAbstractButtonPrivate::click()

{

    Q_Q(QAbstractButton);

    down = false;

    blockRefresh = true;

    bool changeState = true;

    if (checked && queryCheckedButton() == q) {

        // the checked button of an exclusive or autoexclusive group cannot be unchecked

#ifndef QT_NO_BUTTONGROUP

        if (group ? group->d_func()->exclusive : autoExclusive)

#else

        if (autoExclusive)

#endif

            changeState = false;

    }

    QPointer<QAbstractButton> guard(q);

    if (changeState) {

        q->nextCheckState();