#include "qhotkey.h"
#include "qhotkey_p.h"
#include <QCoreApplication>
#include <QAbstractEventDispatcher>
#include <QMetaMethod>
#include <QThread>
#include <QDebug>

QHotkey::QHotkey(QObject *parent) : QObject(parent)
{
    _keyCode = Qt::Key_unknown;
    _modifiers = Qt::NoModifier;
    _nativeShortcut = 0;
    _registered = false;
}

QHotkey::QHotkey(const QKeySequence &sequence, bool autoRegister, QObject *parent) : QHotkey(parent)
{
    setShortcut(sequence, autoRegister);
}

QHotkey::QHotkey(Qt::Key keyCode, Qt::KeyboardModifiers modifiers, bool autoRegister, QObject *parent) : QHotkey(parent)
{
    setShortcut(keyCode, modifiers, autoRegister);
}

QHotkey::QHotkey(const QHotkey::NativeShortcut &shortcut, bool autoRegister, QObject *parent) : QHotkey(parent)
{
    setNativeShortcut(shortcut, autoRegister);
}

QHotkey::~QHotkey()
{
    if (_registered) {
        QHotkeyPrivate::instance()->removeShortcut(this);
    }
}

QKeySequence QHotkey::shortcut() const
{
    if (_keyCode == Qt::Key_unknown) {
        return QKeySequence();
    } else {
        return QKeySequence(_keyCode | _modifiers);
    }
}

Qt::Key QHotkey::keyCode() const
{
    return _keyCode;
}

Qt::KeyboardModifiers QHotkey::modifiers() const
{
    return _modifiers;
}

QHotkey::NativeShortcut QHotkey::currentNativeShortcut() const
{
    return _nativeShortcut;
}

bool QHotkey::isRegistered() const
{
    return _registered;
}

bool QHotkey::setShortcut(const QKeySequence &shortcut, bool autoRegister)
{
    if (shortcut.isEmpty()) {
        return resetShortcut();
    } else if (shortcut.count() > 1) {
        qDebug() << "Keysequences with multiple shortcuts are not allowed Only the first shortcut will be used!";;
    }

    return setShortcut(Qt::Key(shortcut[0] & ~Qt::KeyboardModifierMask),
                       Qt::KeyboardModifiers(shortcut[0] & Qt::KeyboardModifierMask),
                       autoRegister);
}

bool QHotkey::setShortcut(Qt::Key keyCode, Qt::KeyboardModifiers modifiers, bool autoRegister)
{
    if (_registered) {
        if (autoRegister) {
            if (!QHotkeyPrivate::instance()->removeShortcut(this)) {
                return false;
            }
        } else {
            return false;
        }
    }

    if (keyCode == Qt::Key_unknown) {
        _keyCode = Qt::Key_unknown;
        _modifiers = Qt::NoModifier;
        _nativeShortcut = NativeShortcut();
        return true;
    }

    _keyCode = keyCode;
    _modifiers = modifiers;
    _nativeShortcut = QHotkeyPrivate::instance()->nativeShortcut(keyCode, modifiers);
    if (_nativeShortcut.isValid()) {
        if (autoRegister) {
            return QHotkeyPrivate::instance()->addShortcut(this);
        } else {
            return true;
        }
    } else {
        qDebug() << "Unable to map shortcut to native keys. Key:" << keyCode << "Modifiers:" << modifiers;
        _keyCode = Qt::Key_unknown;
        _modifiers = Qt::NoModifier;
        _nativeShortcut = NativeShortcut();
        return false;
    }
}

bool QHotkey::resetShortcut()
{
    if (_registered &&
        !QHotkeyPrivate::instance()->removeShortcut(this)) {
        return false;
    }

    _keyCode = Qt::Key_unknown;
    _modifiers = Qt::NoModifier;
    _nativeShortcut = NativeShortcut();
    return true;
}

bool QHotkey::setNativeShortcut(QHotkey::NativeShortcut nativeShortcut, bool autoRegister)
{
    if (_registered) {
        if (autoRegister) {
            if (!QHotkeyPrivate::instance()->removeShortcut(this)) {
                return false;
            }
        } else {
            return false;
        }
    }

    if (nativeShortcut.isValid()) {
        _keyCode = Qt::Key_unknown;
        _modifiers = Qt::NoModifier;
        _nativeShortcut = nativeShortcut;
        if (autoRegister) {
            return QHotkeyPrivate::instance()->addShortcut(this);
        } else {
            return true;
        }
    } else {
        _keyCode = Qt::Key_unknown;
        _modifiers = Qt::NoModifier;
        _nativeShortcut = NativeShortcut();
        return true;
    }
}

bool QHotkey::setRegistered(bool registered)
{
    if (_registered && !registered) {
        return QHotkeyPrivate::instance()->removeShortcut(this);
    } else if (!_registered && registered) {
        if (!_nativeShortcut.isValid()) {
            return false;
        } else {
            return QHotkeyPrivate::instance()->addShortcut(this);
        }
    } else {
        return true;
    }
}



// ---------- QHotkeyPrivate implementation ----------

QHotkeyPrivate::QHotkeyPrivate()
{
    shortcuts = QMultiHash<QHotkey::NativeShortcut, QHotkey *>();
    Q_ASSERT_X(qApp, Q_FUNC_INFO, "QHotkey requires QCoreApplication to be instantiated");
    qApp->eventDispatcher()->installNativeEventFilter(this);
}

QHotkeyPrivate::~QHotkeyPrivate()
{
    if (!shortcuts.isEmpty()) {
        qDebug() << "QHotkeyPrivate destroyed with registered shortcuts!";
    }
    if (qApp && qApp->eventDispatcher()) {
        qApp->eventDispatcher()->removeNativeEventFilter(this);
    }
}

QHotkey::NativeShortcut QHotkeyPrivate::nativeShortcut(Qt::Key keycode, Qt::KeyboardModifiers modifiers)
{
    Qt::ConnectionType conType = (QThread::currentThread() == thread() ?
                                  Qt::DirectConnection :
                                  Qt::BlockingQueuedConnection);
    QHotkey::NativeShortcut res;
    if (!QMetaObject::invokeMethod(this, "nativeShortcutInvoked", conType,
                                   Q_RETURN_ARG(QHotkey::NativeShortcut, res),
                                   Q_ARG(Qt::Key, keycode),
                                   Q_ARG(Qt::KeyboardModifiers, modifiers))) {
        return QHotkey::NativeShortcut();
    } else {
        return res;
    }
}

bool QHotkeyPrivate::addShortcut(QHotkey *hotkey)
{
    if (hotkey->_registered) {
        return false;
    }

    Qt::ConnectionType conType = (QThread::currentThread() == thread() ?
                                  Qt::DirectConnection :
                                  Qt::BlockingQueuedConnection);
    bool res = false;
    if (!QMetaObject::invokeMethod(this, "addShortcutInvoked", conType,
                                   Q_RETURN_ARG(bool, res),
                                   Q_ARG(QHotkey *, hotkey))) {
        return false;
    } else {
        if (res) {
            emit hotkey->registeredChanged(true);
        }
        return res;
    }
}

bool QHotkeyPrivate::removeShortcut(QHotkey *hotkey)
{
    if (!hotkey->_registered) {
        return false;
    }

    Qt::ConnectionType conType = (QThread::currentThread() == thread() ?
                                  Qt::DirectConnection :
                                  Qt::BlockingQueuedConnection);
    bool res = false;
    if (!QMetaObject::invokeMethod(this, "removeShortcutInvoked", conType,
                                   Q_RETURN_ARG(bool, res),
                                   Q_ARG(QHotkey *, hotkey))) {
        return false;
    } else {
        if (res) {
            emit hotkey->registeredChanged(false);
        }
        return res;
    }
}

void QHotkeyPrivate::activateShortcut(QHotkey::NativeShortcut shortcut)
{
    QMetaMethod signal = QMetaMethod::fromSignal(&QHotkey::activated);
    foreach (QHotkey *hkey, shortcuts.values(shortcut)) {
        signal.invoke(hkey, Qt::QueuedConnection);
    }
}

bool QHotkeyPrivate::addShortcutInvoked(QHotkey *hotkey)
{
    QHotkey::NativeShortcut shortcut = hotkey->_nativeShortcut;

    if (!shortcuts.contains(shortcut)) {
        if (!registerShortcut(shortcut)) {
            return false;
        }
    }

    shortcuts.insert(shortcut, hotkey);
    hotkey->_registered = true;
    return true;
}

bool QHotkeyPrivate::removeShortcutInvoked(QHotkey *hotkey)
{
    QHotkey::NativeShortcut shortcut = hotkey->_nativeShortcut;
    if (shortcuts.remove(shortcut, hotkey) == 0) {
        return false;
    }

    hotkey->_registered = false;
    emit hotkey->registeredChanged(true);

    if (shortcuts.count(shortcut) == 0) {
        return unregisterShortcut(shortcut);
    } else {
        return true;
    }
}

QHotkey::NativeShortcut QHotkeyPrivate::nativeShortcutInvoked(Qt::Key keycode, Qt::KeyboardModifiers modifiers)
{
    bool ok1, ok2 = false;
    quint32 k = nativeKeycode(keycode, ok1);
    quint32 m = nativeModifiers(modifiers, ok2);
    if (ok1 && ok2) {
        return QHotkey::NativeShortcut(k, m);
    } else {
        return QHotkey::NativeShortcut();
    }
}

QHotkey::NativeShortcut::NativeShortcut()
{
    this->key = Qt::Key_unknown;
    this->modifier = Qt::NoModifier;
    this->valid = false;
}

QHotkey::NativeShortcut::NativeShortcut(quint32 key, quint32 modifier)
{
    this->key = key;
    this->modifier = modifier;
    this->valid = true;
}

bool QHotkey::NativeShortcut::isValid() const
{
    return valid;
}

bool QHotkey::NativeShortcut::operator ==(const QHotkey::NativeShortcut &other) const
{
    return (key == other.key) &&
           (modifier == other.modifier) &&
           valid == other.valid;
}

bool QHotkey::NativeShortcut::operator !=(const QHotkey::NativeShortcut &other) const
{
    return (key != other.key) ||
           (modifier != other.modifier) ||
           valid != other.valid;
}

uint qHash(const QHotkey::NativeShortcut &key)
{
    return qHash(key.key) ^ qHash(key.modifier);
}

uint qHash(const QHotkey::NativeShortcut &key, uint seed)
{
    return qHash(key.key, seed) ^ qHash(key.modifier, seed);
}