/********************************************************************
 KWin - the KDE window manager
 This file is part of the KDE project.

Copyright (C) 2016 Martin Gräßlin <mgraesslin@kde.org>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/
#include "device.h"

#include <QDBusConnection>

#include <linux/input.h>

#include <config-kwin.h>

namespace KWin
{
namespace LibInput
{

static bool checkAlphaNumericKeyboard(libinput_device *device)
{
    for (uint i = KEY_1; i <= KEY_0; i++) {
        if (libinput_device_keyboard_has_key(device, i) == 0) {
            return false;
        }
    }
    for (uint i = KEY_Q; i <= KEY_P; i++) {
        if (libinput_device_keyboard_has_key(device, i) == 0) {
            return false;
        }
    }
    for (uint i = KEY_A; i <= KEY_L; i++) {
        if (libinput_device_keyboard_has_key(device, i) == 0) {
            return false;
        }
    }
    for (uint i = KEY_Z; i <= KEY_M; i++) {
        if (libinput_device_keyboard_has_key(device, i) == 0) {
            return false;
        }
    }
    return true;
}

QVector<Device*> Device::s_devices;

Device *Device::getDevice(libinput_device *native)
{
    auto it = std::find_if(s_devices.constBegin(), s_devices.constEnd(),
        [native] (const Device *d) {
            return d->device() == native;
        }
    );
    if (it != s_devices.constEnd()) {
        return *it;
    }
    return nullptr;
}

enum class ConfigKey {
    Enabled,
    LeftHanded,
    DisableWhileTyping,
    PointerAcceleration,
    PointerAccelerationProfile,
    TapToClick,
    LmrTapButtonMap,
    TapAndDrag,
    TapDragLock,
    MiddleButtonEmulation,
    NaturalScroll,
    ScrollMethod,
    ScrollButton
};

struct ConfigData {
    explicit ConfigData(QByteArray _key, void (Device::*_setter)(bool), bool (Device::*_defaultValue)() const = nullptr)
        : key(_key)
    { booleanSetter.setter = _setter; booleanSetter.defaultValue = _defaultValue; }

    explicit ConfigData(QByteArray _key, void (Device::*_setter)(quint32), quint32 (Device::*_defaultValue)() const = nullptr)
        : key(_key)
    { quint32Setter.setter = _setter; quint32Setter.defaultValue = _defaultValue; }

    explicit ConfigData(QByteArray _key, void (Device::*_setter)(QString), QString (Device::*_defaultValue)() const = nullptr)
        : key(_key)
    { stringSetter.setter = _setter; stringSetter.defaultValue = _defaultValue; }

    QByteArray key;

    struct {
        void (Device::*setter)(bool) = nullptr;
        bool (Device::*defaultValue)() const;
    } booleanSetter;

    struct {
        void (Device::*setter)(quint32) = nullptr;
        quint32 (Device::*defaultValue)() const;
    } quint32Setter;
    struct {
        void (Device::*setter)(QString) = nullptr;
        QString (Device::*defaultValue)() const;
    } stringSetter;
};

static const QMap<ConfigKey, ConfigData> s_configData {
    {ConfigKey::Enabled, ConfigData(QByteArrayLiteral("Enabled"), &Device::setEnabled)},
    {ConfigKey::LeftHanded, ConfigData(QByteArrayLiteral("LeftHanded"), &Device::setLeftHanded, &Device::leftHandedEnabledByDefault)},
    {ConfigKey::DisableWhileTyping, ConfigData(QByteArrayLiteral("DisableWhileTyping"), &Device::setDisableWhileTyping, &Device::disableWhileTypingEnabledByDefault)},
    {ConfigKey::PointerAcceleration, ConfigData(QByteArrayLiteral("PointerAcceleration"), &Device::setPointerAccelerationFromString, &Device::defaultPointerAccelerationToString)},
    {ConfigKey::PointerAccelerationProfile, ConfigData(QByteArrayLiteral("PointerAccelerationProfile"), &Device::setPointerAccelerationProfileFromInt, &Device::defaultPointerAccelerationProfileToInt)},
    {ConfigKey::TapToClick, ConfigData(QByteArrayLiteral("TapToClick"), &Device::setTapToClick, &Device::tapToClickEnabledByDefault)},
    {ConfigKey::TapAndDrag, ConfigData(QByteArrayLiteral("TapAndDrag"), &Device::setTapAndDrag, &Device::tapAndDragEnabledByDefault)},
    {ConfigKey::TapDragLock, ConfigData(QByteArrayLiteral("TapDragLock"), &Device::setTapDragLock, &Device::tapDragLockEnabledByDefault)},
    {ConfigKey::MiddleButtonEmulation, ConfigData(QByteArrayLiteral("MiddleButtonEmulation"), &Device::setMiddleEmulation, &Device::middleEmulationEnabledByDefault)},
    {ConfigKey::LmrTapButtonMap, ConfigData(QByteArrayLiteral("LmrTapButtonMap"), &Device::setLmrTapButtonMap, &Device::lmrTapButtonMapEnabledByDefault)},
    {ConfigKey::NaturalScroll, ConfigData(QByteArrayLiteral("NaturalScroll"), &Device::setNaturalScroll, &Device::naturalScrollEnabledByDefault)},
    {ConfigKey::ScrollMethod, ConfigData(QByteArrayLiteral("ScrollMethod"), &Device::activateScrollMethodFromInt, &Device::defaultScrollMethodToInt)},
    {ConfigKey::ScrollButton, ConfigData(QByteArrayLiteral("ScrollButton"), &Device::setScrollButton, &Device::defaultScrollButton)}
};

Device::Device(libinput_device *device, QObject *parent)
    : QObject(parent)
    , m_device(device)
    , m_keyboard(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_KEYBOARD))
    , m_pointer(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_POINTER))
    , m_touch(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_TOUCH))
    , m_tabletTool(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_TABLET_TOOL))
#if 0
    // next libinput version
    , m_tabletPad(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_TABLET_PAD))
#else
    , m_tabletPad(false)
#endif
    , m_supportsGesture(libinput_device_has_capability(m_device, LIBINPUT_DEVICE_CAP_GESTURE))
    , m_name(QString::fromLocal8Bit(libinput_device_get_name(m_device)))
    , m_sysName(QString::fromLocal8Bit(libinput_device_get_sysname(m_device)))
    , m_outputName(QString::fromLocal8Bit(libinput_device_get_output_name(m_device)))
    , m_product(libinput_device_get_id_product(m_device))
    , m_vendor(libinput_device_get_id_vendor(m_device))
    , m_tapFingerCount(libinput_device_config_tap_get_finger_count(m_device))
    , m_defaultTapButtonMap(libinput_device_config_tap_get_default_button_map(m_device))
    , m_tapButtonMap(libinput_device_config_tap_get_button_map(m_device))
    , m_tapToClickEnabledByDefault(libinput_device_config_tap_get_default_enabled(m_device) == LIBINPUT_CONFIG_TAP_ENABLED)
    , m_tapToClick(libinput_device_config_tap_get_enabled(m_device))
    , m_tapAndDragEnabledByDefault(libinput_device_config_tap_get_default_drag_enabled(m_device))
    , m_tapAndDrag(libinput_device_config_tap_get_drag_enabled(m_device))
    , m_tapDragLockEnabledByDefault(libinput_device_config_tap_get_default_drag_lock_enabled(m_device))
    , m_tapDragLock(libinput_device_config_tap_get_drag_lock_enabled(m_device))
    , m_supportsDisableWhileTyping(libinput_device_config_dwt_is_available(m_device))
    , m_supportsPointerAcceleration(libinput_device_config_accel_is_available(m_device))
    , m_supportsLeftHanded(libinput_device_config_left_handed_is_available(m_device))
    , m_supportsCalibrationMatrix(libinput_device_config_calibration_has_matrix(m_device))
    , m_supportsDisableEvents(libinput_device_config_send_events_get_modes(m_device) & LIBINPUT_CONFIG_SEND_EVENTS_DISABLED)
    , m_supportsDisableEventsOnExternalMouse(libinput_device_config_send_events_get_modes(m_device) & LIBINPUT_CONFIG_SEND_EVENTS_DISABLED_ON_EXTERNAL_MOUSE)
    , m_supportsMiddleEmulation(libinput_device_config_middle_emulation_is_available(m_device))
    , m_supportsNaturalScroll(libinput_device_config_scroll_has_natural_scroll(m_device))
    , m_supportedScrollMethods(libinput_device_config_scroll_get_methods(m_device))
    , m_leftHandedEnabledByDefault(libinput_device_config_left_handed_get_default(m_device))
    , m_middleEmulationEnabledByDefault(libinput_device_config_middle_emulation_get_default_enabled(m_device) == LIBINPUT_CONFIG_MIDDLE_EMULATION_ENABLED)
    , m_naturalScrollEnabledByDefault(libinput_device_config_scroll_get_default_natural_scroll_enabled(m_device))
    , m_defaultScrollMethod(libinput_device_config_scroll_get_default_method(m_device))
    , m_defaultScrollButton(libinput_device_config_scroll_get_default_button(m_device))
    , m_disableWhileTypingEnabledByDefault(libinput_device_config_dwt_get_default_enabled(m_device))
    , m_disableWhileTyping(m_supportsDisableWhileTyping ? libinput_device_config_dwt_get_enabled(m_device) == LIBINPUT_CONFIG_DWT_ENABLED : false)
    , m_middleEmulation(libinput_device_config_middle_emulation_get_enabled(m_device) == LIBINPUT_CONFIG_MIDDLE_EMULATION_ENABLED)
    , m_leftHanded(m_supportsLeftHanded ? libinput_device_config_left_handed_get(m_device) : false)
    , m_naturalScroll(m_supportsNaturalScroll ? libinput_device_config_scroll_get_natural_scroll_enabled(m_device) : false)
    , m_scrollMethod(libinput_device_config_scroll_get_method(m_device))
    , m_scrollButton(libinput_device_config_scroll_get_button(m_device))
    , m_defaultPointerAcceleration(libinput_device_config_accel_get_default_speed(m_device))
    , m_pointerAcceleration(libinput_device_config_accel_get_speed(m_device))
    , m_supportedPointerAccelerationProfiles(libinput_device_config_accel_get_profiles(m_device))
    , m_defaultPointerAccelerationProfile(libinput_device_config_accel_get_default_profile(m_device))
    , m_pointerAccelerationProfile(libinput_device_config_accel_get_profile(m_device))
    , m_enabled(m_supportsDisableEvents ? libinput_device_config_send_events_get_mode(m_device) == LIBINPUT_CONFIG_SEND_EVENTS_ENABLED : true)
    , m_config()
{
    libinput_device_ref(m_device);

    qreal width = 0;
    qreal height = 0;
    if (libinput_device_get_size(m_device, &width, &height) == 0) {
        m_size = QSizeF(width, height);
    }
    if (m_pointer) {
        if (libinput_device_pointer_has_button(m_device, BTN_LEFT) == 1) {
            m_supportedButtons |= Qt::LeftButton;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_MIDDLE) == 1) {
            m_supportedButtons |= Qt::MiddleButton;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_RIGHT) == 1) {
            m_supportedButtons |= Qt::RightButton;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_SIDE) == 1) {
            m_supportedButtons |= Qt::ExtraButton1;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_EXTRA) == 1) {
            m_supportedButtons |= Qt::ExtraButton2;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_BACK) == 1) {
            m_supportedButtons |= Qt::BackButton;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_FORWARD) == 1) {
            m_supportedButtons |= Qt::ForwardButton;
        }
        if (libinput_device_pointer_has_button(m_device, BTN_TASK) == 1) {
            m_supportedButtons |= Qt::TaskButton;
        }
    }
    if (m_keyboard) {
        m_alphaNumericKeyboard = checkAlphaNumericKeyboard(m_device);
    }

    s_devices << this;
    QDBusConnection::sessionBus().registerObject(QStringLiteral("/org/kde/KWin/InputDevice/") + m_sysName,
                                                 QStringLiteral("org.kde.KWin.InputDevice"),
                                                 this,
                                                 QDBusConnection::ExportAllProperties
    );
}

Device::~Device()
{
    s_devices.removeOne(this);
    QDBusConnection::sessionBus().unregisterObject(QStringLiteral("/org/kde/KWin/InputDevice/") + m_sysName);
    libinput_device_unref(m_device);
}

template <typename T>
void Device::writeEntry(const ConfigKey &key, const T &value)
{
    if (!m_config.isValid()) {
        return;
    }
    if (m_loading) {
        return;
    }
    auto it = s_configData.find(key);
    Q_ASSERT(it != s_configData.end());
    m_config.writeEntry(it.value().key.constData(), value);
    m_config.sync();
}

template <typename T, typename Setter>
void Device::readEntry(const QByteArray &key, const Setter &s, const T &defaultValue)
{
    if (!s.setter) {
        return;
    }

    (this->*(s.setter))(m_config.readEntry(key.constData(), s.defaultValue ? (this->*(s.defaultValue))() : defaultValue));
}

void Device::loadConfiguration()
{
    if (!m_config.isValid()) {
        return;
    }
    m_loading = true;
    for (auto it = s_configData.begin(), end = s_configData.end(); it != end; ++it) {
        const auto key = it.value().key;
        if (!m_config.hasKey(key.constData())) {
            continue;
        }
        readEntry(key, it.value().booleanSetter, true);
        readEntry(key, it.value().quint32Setter, 0);
        readEntry(key, it.value().stringSetter, "");
    };

    m_loading = false;
}

void Device::setPointerAcceleration(qreal acceleration)
{
    if (!m_supportsPointerAcceleration) {
        return;
    }
    acceleration = qBound(-1.0, acceleration, 1.0);
    if (libinput_device_config_accel_set_speed(m_device, acceleration) == LIBINPUT_CONFIG_STATUS_SUCCESS) {
        if (m_pointerAcceleration != acceleration) {
            m_pointerAcceleration = acceleration;
            emit pointerAccelerationChanged();
            writeEntry(ConfigKey::PointerAcceleration, QString::number(acceleration, 'f', 3));
        }
    }
}

void Device::setScrollButton(quint32 button)
{
    if (!(m_supportedScrollMethods & LIBINPUT_CONFIG_SCROLL_ON_BUTTON_DOWN)) {
        return;
    }
    if (libinput_device_config_scroll_set_button(m_device, button) == LIBINPUT_CONFIG_STATUS_SUCCESS) {
        if (m_scrollButton != button) {
            m_scrollButton = button;
            writeEntry(ConfigKey::ScrollButton, m_scrollButton);
            emit scrollButtonChanged();
        }
    }
}

void Device::setPointerAccelerationProfile(bool set, enum  libinput_config_accel_profile profile)
{
    if (!(m_supportedPointerAccelerationProfiles & profile)) {
        return;
    }
    if (!set) {
        profile = (profile == LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT) ? LIBINPUT_CONFIG_ACCEL_PROFILE_ADAPTIVE : LIBINPUT_CONFIG_ACCEL_PROFILE_FLAT;
        if (!(m_supportedPointerAccelerationProfiles & profile)) {
            return;
        }
    }

    if (libinput_device_config_accel_set_profile(m_device, profile) == LIBINPUT_CONFIG_STATUS_SUCCESS) {
        if (m_pointerAccelerationProfile != profile) {
            m_pointerAccelerationProfile = profile;
            emit pointerAccelerationProfileChanged();
            writeEntry(ConfigKey::PointerAccelerationProfile, (quint32) profile);
        }
    }
}

void Device::setScrollMethod(bool set, enum libinput_config_scroll_method method)
{
    if (!(m_supportedScrollMethods & method)) {
        return;
    }

    bool isCurrent = m_scrollMethod == method;
    if (!set) {
        if (isCurrent) {
            method = LIBINPUT_CONFIG_SCROLL_NO_SCROLL;
            isCurrent = false;
        } else {
            return;
        }
    }

    if (libinput_device_config_scroll_set_method(m_device, method) == LIBINPUT_CONFIG_STATUS_SUCCESS) {
        if (!isCurrent) {
            m_scrollMethod = method;
            emit scrollMethodChanged();
            writeEntry(ConfigKey::ScrollMethod, (quint32) method);
        }
    }
}

void Device::setLmrTapButtonMap(bool set)
{
    enum libinput_config_tap_button_map map = set ? LIBINPUT_CONFIG_TAP_MAP_LMR : LIBINPUT_CONFIG_TAP_MAP_LRM;

    if (m_tapFingerCount < 2) {
        return;
    }
    if (!set) {
        map = LIBINPUT_CONFIG_TAP_MAP_LRM;
    }

    if (libinput_device_config_tap_set_button_map(m_device, map) == LIBINPUT_CONFIG_STATUS_SUCCESS) {
        if (m_tapButtonMap != map) {
            m_tapButtonMap = map;
            writeEntry(ConfigKey::LmrTapButtonMap, set);
            emit tapButtonMapChanged();
        }
    }
}

#define CONFIG(method, condition, function, variable, key) \
void Device::method(bool set) \
{ \
    if (condition) { \
        return; \
    } \
    if (libinput_device_config_##function(m_device, set) == LIBINPUT_CONFIG_STATUS_SUCCESS) { \
        if (m_##variable != set) { \
            m_##variable = set; \
            writeEntry(ConfigKey::key, m_##variable); \
            emit variable##Changed(); \
        }\
    } \
}

CONFIG(setLeftHanded, !m_supportsLeftHanded, left_handed_set, leftHanded, LeftHanded)
CONFIG(setNaturalScroll, !m_supportsNaturalScroll, scroll_set_natural_scroll_enabled, naturalScroll, NaturalScroll)

#undef CONFIG

#define CONFIG(method, condition, function, enum, variable, key) \
void Device::method(bool set) \
{ \
    if (condition) { \
        return; \
    } \
    if (libinput_device_config_##function(m_device, set ? LIBINPUT_CONFIG_##enum##_ENABLED : LIBINPUT_CONFIG_##enum##_DISABLED) == LIBINPUT_CONFIG_STATUS_SUCCESS) { \
        if (m_##variable != set) { \
            m_##variable = set; \
            writeEntry(ConfigKey::key, m_##variable); \
            emit variable##Changed(); \
        }\
    } \
}

CONFIG(setEnabled, !m_supportsDisableEvents, send_events_set_mode, SEND_EVENTS, enabled, Enabled)
CONFIG(setDisableWhileTyping, !m_supportsDisableWhileTyping, dwt_set_enabled, DWT, disableWhileTyping, DisableWhileTyping)
CONFIG(setTapToClick, m_tapFingerCount == 0, tap_set_enabled, TAP, tapToClick, TapToClick)
CONFIG(setTapAndDrag, false, tap_set_drag_enabled, DRAG, tapAndDrag, TapAndDrag)
CONFIG(setTapDragLock, false, tap_set_drag_lock_enabled, DRAG_LOCK, tapDragLock, TapDragLock)
CONFIG(setMiddleEmulation, m_supportsMiddleEmulation == false, middle_emulation_set_enabled, MIDDLE_EMULATION, middleEmulation, MiddleButtonEmulation)

#undef CONFIG

}
}