// Copyright (C) 2015-2016 Oleksandr Tymoshenko <gonzo@bluezbox.com>
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

#include "qbsdmouse.h"

#include <QFile>
#include <QSocketNotifier>
#include <QStringList>
#include <QPoint>
#include <QGuiApplication>
#include <qpa/qwindowsysteminterface.h>
#include <private/qguiapplication_p.h>
#include <private/qinputdevicemanager_p_p.h>

#include <private/qcore_unix_p.h>
#include <qdebug.h>

#include <errno.h>
#include <fcntl.h>
#include <sys/mouse.h>
#include <unistd.h>

QT_BEGIN_NAMESPACE

enum {
    PsmLevelBasic = 0,
    PsmLevelExtended = 1,
    PsmLevelNative = 2
};

QBsdMouseHandler::QBsdMouseHandler(const QString &key, const QString &specification)
{
    Q_UNUSED(key);

    setObjectName(QLatin1String("BSD Sysmouse Handler"));

    QByteArray device;
    if (specification.startsWith("/dev/"))
        device = QFile::encodeName(specification);

    if (device.isEmpty())
        device = QByteArrayLiteral("/dev/sysmouse");

    m_devFd = QT_OPEN(device.constData(), O_RDONLY);
    if (m_devFd < 0) {
        qErrnoWarning(errno, "open(%s) failed", device.constData());
        return;
    }

    int level = 0;
    if (ioctl(m_devFd, MOUSE_GETLEVEL, &level)) {
        qErrnoWarning(errno, "ioctl(%s, MOUSE_GETLEVEL) failed", device.constData());
        close(m_devFd);
        m_devFd = -1;
        return;
    }

    switch (level) {
    case PsmLevelBasic:
        m_packetSize = 5;
        break;
    case PsmLevelExtended:
        m_packetSize = 8;
        break;
    default:
        qWarning("Unsupported mouse device operation level: %d", level);
        close(m_devFd);
        m_devFd = -1;
        return;
    }

    if (fcntl(m_devFd, F_SETFL, O_NONBLOCK)) {
        qErrnoWarning(errno, "fcntl(%s, F_SETFL, O_NONBLOCK) failed", device.constData());
        close(m_devFd);
        m_devFd = -1;
        return;
    }

    m_notifier.reset(new QSocketNotifier(m_devFd, QSocketNotifier::Read, this));
    connect(m_notifier.data(), &QSocketNotifier::activated, this, &QBsdMouseHandler::readMouseData);
    QInputDeviceManagerPrivate::get(QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
        QInputDeviceManager::DeviceTypePointer, 1);
}

QBsdMouseHandler::~QBsdMouseHandler()
{
    if (m_devFd != -1)
        close(m_devFd);
}

void QBsdMouseHandler::readMouseData()
{
    if (m_devFd < 0)
        return;

    if (m_packetSize == 0)
        return;

    // packet format described in mouse(4)
    qint8 packet[MOUSE_SYS_PACKETSIZE];
    quint8 status = 0;
    while (read(m_devFd, packet, m_packetSize) == m_packetSize) {
        const qint16 relx = packet[1] + packet[3];
        const qint16 rely = -(packet[2] + packet[4]);

        m_x += relx;
        m_y += rely;

        status = packet[0] & MOUSE_SYS_STDBUTTONS;
    }

    // clamp to screen geometry
    const QRect g = QGuiApplication::primaryScreen()->virtualGeometry();
    if (m_x + m_xOffset < g.left())
        m_x = g.left() - m_xOffset;
    else if (m_x + m_xOffset > g.right())
        m_x = g.right() - m_xOffset;

    if (m_y + m_yOffset < g.top())
        m_y = g.top() - m_yOffset;
    else if (m_y + m_yOffset > g.bottom())
        m_y = g.bottom() - m_yOffset;

    const QPoint pos(m_x + m_xOffset, m_y + m_yOffset);
    m_buttons = Qt::NoButton;
    if (!(status & MOUSE_SYS_BUTTON1UP))
        m_buttons |= Qt::LeftButton;
    if (!(status & MOUSE_SYS_BUTTON2UP))
        m_buttons |= Qt::MiddleButton;
    if (!(status & MOUSE_SYS_BUTTON3UP))
        m_buttons |= Qt::RightButton;

    QWindowSystemInterface::handleMouseEvent(0, pos, pos, m_buttons);
}

QT_END_NAMESPACE