File indexing completed on 2024-12-01 13:34:29

 /*
     SPDX-License-Identifier: GPL-2.0-only
     SPDX-FileCopyrightText: 1999-2002 Lubos Lunak <l.lunak@kde.org>
  */
 
 #include "gestures.h"
 
 #include <math.h>
 
 #include "khotkeysglobal.h"
 
 #include "action_data/action_data.h"
 #include "input.h"
 
 #include <QApplication>
 #include <QDebug>
 
 #include <kkeyserver.h>
 #include <kxerrorhandler.h>
 
 #include "windows_helper/window_selection_list.h"
 
 // only necessary for circumventing bug #173606, see below
 #include <QX11Info>
 #include <X11/Xlib.h>
 
 namespace KHotKeys
 {
 QPointer<Gesture> gesture_handler = nullptr;
 
 Gesture::Gesture(bool enabled_P, QObject *parent_P)
     : QObject(parent_P)
     , _enabled(false)
     , recording(false)
     , button(0)
     , exclude(nullptr)
 {
     Q_UNUSED(enabled_P);
     // qDebug() << enabled_P;
     nostroke_timer.setSingleShot(true);
     connect(&nostroke_timer, SIGNAL(timeout()), SLOT(stroke_timeout()));
     connect(windows_handler, SIGNAL(active_window_changed(WId)), SLOT(active_window_changed(WId)));
 }
 
 Gesture::~Gesture()
 {
     enable(false);
 }
 
 void Gesture::enable(bool enabled_P)
 {
     // qDebug() << enabled_P;
     if (_enabled == enabled_P)
         return;
     _enabled = enabled_P;
     update_grab();
 }
 
 void Gesture::set_exclude(Windowdef_list *windows_P)
 {
     delete exclude;
     // check for count() > 0 - empty exclude list means no window is excluded,
     // but empty Windowdef_list matches everything
     if (windows_P != nullptr && windows_P->count() > 0)
         exclude = windows_P->copy();
     else
         exclude = nullptr;
     update_grab();
 }
 
 void Gesture::update_grab()
 {
     // qDebug() << "Enabled:" << _enabled;
     // qDebug() << "Handler:" << handlers.count();
     // qDebug() << "Exclude:" << exclude << " Match? " << (exclude && exclude->match( Window_data( windows_handler->active_window())));
 
     if (!QX11Info::isPlatformX11()) {
         return;
     }
 
     if (_enabled && handlers.count() > 0 && (exclude == nullptr || !exclude->match(Window_data(windows_handler->active_window())))) {
         qApp->removeNativeEventFilter(this); // avoid being installed twice
         qApp->installNativeEventFilter(this);
         // CHECKME grab only when there's at least one gesture?
         grab_mouse(true);
     } else {
         grab_mouse(false);
         qApp->removeNativeEventFilter(this);
     }
 }
 
 void Gesture::active_window_changed(WId)
 {
     update_grab();
 }
 
 void Gesture::handleScore(ActionData *const data, const qreal score)
 {
     if (score > maxScore) {
         maxScore = score;
         bestFit = data;
     }
 }
 
 void Gesture::register_handler(QObject *receiver_P, const char *slot_P)
 {
     if (handlers.contains(receiver_P))
         return;
     handlers[receiver_P] = true;
     // connect directly because we want to be sure that all triggers submitted
     // their scores back to this object before executing the best match we
     // could find.
     connect(this, SIGNAL(handle_gesture(StrokePoints)), receiver_P, slot_P, Qt::DirectConnection);
     // clang-format off
     connect(receiver_P, SIGNAL(gotScore(ActionData*const,qreal)), this, SLOT(handleScore(ActionData*const,qreal)), Qt::DirectConnection);
     // clang-format on
     if (handlers.count() == 1)
         update_grab();
 }
 
 void Gesture::unregister_handler(QObject *receiver_P, const char *slot_P)
 {
     if (!handlers.contains(receiver_P))
         return;
     handlers.remove(receiver_P);
 
     disconnect(this, SIGNAL(handle_gesture(StrokePoints)), receiver_P, slot_P);
     // clang-format off
     disconnect(receiver_P, SIGNAL(gotScore(ActionData*const,qreal)), this, SLOT(handleScore(ActionData*const,qreal)));
     // clang-format on
     if (handlers.count() == 0)
         update_grab();
 }
 
 bool Gesture::nativeEventFilter(const QByteArray &eventType, void *message, long *)
 {
     if (eventType != "xcb_generic_event_t") {
         return false;
     }
 
     xcb_generic_event_t *generic_event = static_cast<xcb_generic_event_t *>(message);
     const uint8_t type = generic_event->response_type & ~0x80;
 
     if (type == XCB_BUTTON_PRESS) {
         xcb_button_press_event_t *event = static_cast<xcb_button_press_event_t *>(message);
 
         if (event->detail != button)
             return false;
 
         qDebug() << "GESTURE: mouse press";
         stroke.reset();
         stroke.record(event->event_x, event->event_y);
         nostroke_timer.start(timeout);
         recording = true;
         start_x = event->event_x;
         start_y = event->event_y;
         return true;
     }
     // if stroke is finished... postprocess the data and send a signal.
     // then wait for incoming matching scores and execute the best fit.
     else if (type == XCB_BUTTON_RELEASE && recording) {
         xcb_button_release_event_t *event = static_cast<xcb_button_release_event_t *>(message);
 
         if (event->detail != button)
             return false;
 
         recording = false;
         nostroke_timer.stop();
         stroke.record(event->event_x, event->event_y);
         StrokePoints gesture(stroke.processData());
         if (gesture.isEmpty()) {
             qDebug() << "GESTURE: replay";
             XAllowEvents(QX11Info::display(), AsyncPointer, CurrentTime);
             XUngrabPointer(QX11Info::display(), CurrentTime);
             mouse_replay(true);
             return true;
         }
 
         // prepare for the incoming scores from different triggers
         maxScore = 0.0;
         bestFit = nullptr;
 
         emit handle_gesture(gesture);
         // the signal is emitted directly, so we get all trigger scores before
         // the next lines are executed. bestFit should now contain
         // a pointer to the ActionData with the best-matching gesture.
 
         if (bestFit != nullptr) {
             // set up the windows_handler
             WId window = windows_handler->window_at_position(start_x, start_y);
             windows_handler->set_action_window(window);
             // then execute the action associated with the best match.
             bestFit->execute();
         }
 
         return true;
     } else if (type == XCB_MOTION_NOTIFY && recording) {
         xcb_motion_notify_event_t *event = static_cast<xcb_motion_notify_event_t *>(message);
 
         // ignore small initial movement
         if (nostroke_timer.isActive() && abs(start_x - event->event_x) < 10 && abs(start_y - event->event_y) < 10)
             return true;
         nostroke_timer.stop();
 
         stroke.record(event->event_x, event->event_y);
     }
     return false;
 }
 
 void Gesture::stroke_timeout()
 {
     // qDebug() << "GESTURE: timeout";
     XAllowEvents(QX11Info::display(), AsyncPointer, CurrentTime);
     XUngrabPointer(QX11Info::display(), CurrentTime);
     mouse_replay(false);
 
     // for xorg-server 1.7 to 1.9 RC4: disable drag'n'drop support to evade bug #173606
     if (VendorRelease(QX11Info::display()) < 10899905 && VendorRelease(QX11Info::display()) >= 10700000)
         mouse_replay(true);
 
     recording = false;
 }
 
 void Gesture::mouse_replay(bool release_P)
 {
     bool was_enabled = _enabled;
     enable(false);
     Mouse::send_mouse_button(button, release_P);
     enable(was_enabled);
 }
 
 void Gesture::grab_mouse(bool grab_P)
 {
     // qDebug() << grab_P;
 
     if (grab_P) {
         // qDebug() << "gesture grab";
         Q_ASSERT(button != 0);
         KXErrorHandler handler;
         static int mask[] = {0,
                              Button1MotionMask,
                              Button2MotionMask,
                              Button3MotionMask,
                              Button4MotionMask,
                              Button5MotionMask,
                              ButtonMotionMask,
                              ButtonMotionMask,
                              ButtonMotionMask,
                              ButtonMotionMask};
 #define XCapL KKeyServer::modXLock()
 #define XNumL KKeyServer::modXNumLock()
 #define XScrL KKeyServer::modXScrollLock()
         unsigned int mods[8] = {0, XCapL, XNumL, XNumL | XCapL, XScrL, XScrL | XCapL, XScrL | XNumL, XScrL | XNumL | XCapL};
 #undef XCapL
 #undef XNumL
 #undef XScrL
         for (int i = 0; i < 8; ++i)
             XGrabButton(QX11Info::display(),
                         button,
                         mods[i],
                         QX11Info::appRootWindow(),
                         False,
                         ButtonPressMask | ButtonReleaseMask | mask[button],
                         GrabModeAsync,
                         GrabModeAsync,
                         None,
                         None);
         bool err = handler.error(true);
         Q_UNUSED(err);
         // qDebug() << "Gesture grab:" << err;
     } else {
         // qDebug() << "Gesture ungrab";
         XUngrabButton(QX11Info::display(), button, AnyModifier, QX11Info::appRootWindow());
     }
 }
 
 void Gesture::set_mouse_button(unsigned int button_P)
 {
     if (button == button_P)
         return;
     if (!_enabled) {
         button = button_P;
         return;
     }
     grab_mouse(false);
     button = button_P;
     grab_mouse(true);
 }
 
 void Gesture::set_timeout(int timeout_P)
 {
     timeout = timeout_P;
 }
 
 // Definitions for Gesture end here, Definitions for Stroke following.
 
 Stroke::Stroke()
 {
     reset();
     points = new point[MAX_POINTS]; // CHECKME
 }
 
 Stroke::~Stroke()
 {
     delete[] points;
 }
 
 void Stroke::reset()
 {
     min_x = 10000;
     min_y = 10000;
     max_x = -1;
     max_y = -1;
     point_count = -1;
 }
 
 bool Stroke::record(int x, int y)
 {
     if (point_count == -1) {
         ++point_count;
         points[point_count].x = x;
         points[point_count].y = y;
 
         // start metrics
         min_x = max_x = x;
         min_y = max_y = y;
     } else {
         ++point_count;
         if (point_count >= MAX_POINTS)
             return false;
         points[point_count].x = x;
         points[point_count].y = y;
 
         // update metrics
         if (x < min_x)
             min_x = x;
         if (x > max_x)
             max_x = x;
         if (y < min_y)
             min_y = y;
         if (y > max_y)
             max_y = y;
     }
     return true;
 }
 
 // Compute some additional data from the raw point coordinates and store
 // it all in a new data structure to be passed on and saved.
 
 StrokePoints Stroke::processData()
 {
     if (point_count < 2)
         return StrokePoints(); // empty vector
 
     int n = point_count - 1;
 
     StrokePoints results(n);
 
     // calculate s, where s is the length of a stroke up to the current point
     // (first loop) divided by the total stroke length (second loop)
     qreal strokelength = 0.0;
     results[0].s = 0.0;
 
     for (int i = 0; i < n - 1; i++) {
         strokelength += hypot(points[i + 1].x - points[i].x, points[i + 1].y - points[i].y);
         results[i + 1].s = strokelength;
     }
 
     for (int i = 0; i < n; i++)
         results[i].s /= strokelength;
 
     // check which axis is longer...
     int scaleX = max_x - min_x;
     int scaleY = max_y - min_y;
     qreal scale = (scaleX > scaleY) ? scaleX : scaleY;
 
     // ...and scale the stroke coordinates to a new size depending on this axis
     // (saving into the new data structure for higher precision)
     for (int i = 0; i < n; i++) {
         results[i].x = (points[i].x - (min_x + max_x) / 2.0) / scale + 0.5;
         results[i].y = (points[i].y - (min_y + max_y) / 2.0) / scale + 0.5;
     }
 
     // calculate values of delta_s and angle for the points by simple comparison
     // with the respective successor.
     // delta_s is the distance to the successor in the same units as s.
     // angle is the angle to the successor in units of pi.
     for (int i = 0; i < n - 1; i++) {
         results[i].delta_s = results[i + 1].s - results[i].s;
         results[i].angle = atan2(results[i + 1].y - results[i].y, results[i + 1].x - results[i].x) / M_PI;
     }
 
     // last point of result would need special logic, so we simply discard it -
     // there's enough points anyway
     results.pop_back();
 
     return results;
 }
 
 } // namespace KHotKeys
 
 #include "moc_gestures.cpp"