wl_pointer_handle.h

#ifndef WL_PTR_HANDLER_H
#define WL_PTR_HANDLER_H

#include "client_state.h"
#include <wayland-client.h>

enum pointer_event_mask
{
  POINTER_EVENT_ENTER         = 1 << 0,
  POINTER_EVENT_LEAVE         = 1 << 1,
  POINTER_EVENT_MOTION        = 1 << 2,
  POINTER_EVENT_BUTTON        = 1 << 3,
  POINTER_EVENT_AXIS          = 1 << 4,
  POINTER_EVENT_AXIS_SOURCE   = 1 << 5,
  POINTER_EVENT_AXIS_STOP     = 1 << 6,
  POINTER_EVENT_AXIS_DISCRETE = 1 << 7,
};

static void wl_pointer_enter(void* data, struct wl_pointer* wl_pointer, uint32_t serial,
                             struct wl_surface* surface, wl_fixed_t surface_x, wl_fixed_t surface_y)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_ENTER;
  client_state->pointer_event.serial    = serial;
  client_state->pointer_event.surface_x = surface_x,
  client_state->pointer_event.surface_y = surface_y;
}

static void wl_pointer_leave(void* data, struct wl_pointer* wl_pointer, uint32_t serial,
                             struct wl_surface* surface)
{
  struct client_state* client_state  = data;
  client_state->pointer_event.serial = serial;
  client_state->pointer_event.event_mask |= POINTER_EVENT_LEAVE;
}

static void wl_pointer_motion(void* data, struct wl_pointer* wl_pointer, uint32_t time,
                              wl_fixed_t surface_x, wl_fixed_t surface_y)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_MOTION;
  client_state->pointer_event.time      = time;
  client_state->pointer_event.surface_x = surface_x,
  client_state->pointer_event.surface_y = surface_y;
}

static void wl_pointer_button(void* data, struct wl_pointer* wl_pointer, uint32_t serial,
                              uint32_t time, uint32_t button, uint32_t state)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_BUTTON;
  client_state->pointer_event.time   = time;
  client_state->pointer_event.serial = serial;
  client_state->pointer_event.button = button, client_state->pointer_event.state = state;
}

static void wl_pointer_axis(void* data, struct wl_pointer* wl_pointer, uint32_t time, uint32_t axis,
                            wl_fixed_t value)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_AXIS;
  client_state->pointer_event.time             = time;
  client_state->pointer_event.axes[axis].valid = true;
  client_state->pointer_event.axes[axis].value = value;
}

static void wl_pointer_axis_source(void* data, struct wl_pointer* wl_pointer, uint32_t axis_source)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_AXIS_SOURCE;
  client_state->pointer_event.axis_source = axis_source;
}

static void wl_pointer_axis_stop(void* data, struct wl_pointer* wl_pointer, uint32_t time,
                                 uint32_t axis)
{
  struct client_state* client_state = data;
  client_state->pointer_event.time  = time;
  client_state->pointer_event.event_mask |= POINTER_EVENT_AXIS_STOP;
  client_state->pointer_event.axes[axis].valid = true;
}

static void wl_pointer_axis_discrete(void* data, struct wl_pointer* wl_pointer, uint32_t axis,
                                     int32_t discrete)
{
  struct client_state* client_state = data;
  client_state->pointer_event.event_mask |= POINTER_EVENT_AXIS_DISCRETE;
  client_state->pointer_event.axes[axis].valid    = true;
  client_state->pointer_event.axes[axis].discrete = discrete;
}

static void wl_pointer_frame(void* data, struct wl_pointer* wl_pointer)
{
  struct client_state*  client_state = data;
  struct pointer_event* event        = &client_state->pointer_event;
  log_message(LOG_LEVEL_DEBUG, "pointer frame @ %d: ", event->time);

  if (event->event_mask & POINTER_EVENT_ENTER)
  {
    log_message(LOG_LEVEL_DEBUG, "entered %f, %f", wl_fixed_to_double(event->surface_x),
                wl_fixed_to_double(event->surface_y));
  }

  if (event->event_mask & POINTER_EVENT_LEAVE)
  {
    log_message(LOG_LEVEL_DEBUG, "pointer on leave");
  }

  if (event->event_mask & POINTER_EVENT_MOTION)
  {
    log_message(LOG_LEVEL_DEBUG, "motion %f, %f", wl_fixed_to_double(event->surface_x),
                wl_fixed_to_double(event->surface_y));
  }

  if (event->event_mask & POINTER_EVENT_BUTTON)
  {
    char* state = event->state == WL_POINTER_BUTTON_STATE_RELEASED ? "released" : "pressed";
    log_message(LOG_LEVEL_DEBUG, "[DEBUG] button %d %s", event->button, state);
  }

  uint32_t axis_events = POINTER_EVENT_AXIS | POINTER_EVENT_AXIS_SOURCE | POINTER_EVENT_AXIS_STOP |
                         POINTER_EVENT_AXIS_DISCRETE;
  char* axis_name[2] = {
    [WL_POINTER_AXIS_VERTICAL_SCROLL]   = "vertical",
    [WL_POINTER_AXIS_HORIZONTAL_SCROLL] = "horizontal",
  };
  char* axis_source[4] = {
    [WL_POINTER_AXIS_SOURCE_WHEEL]      = "wheel",
    [WL_POINTER_AXIS_SOURCE_FINGER]     = "finger",
    [WL_POINTER_AXIS_SOURCE_CONTINUOUS] = "continuous",
    [WL_POINTER_AXIS_SOURCE_WHEEL_TILT] = "wheel tilt",
  };
  if (event->event_mask & axis_events)
  {
    for (size_t i = 0; i < 2; ++i)
    {
      if (!event->axes[i].valid)
      {
        continue;
      }
      log_message(LOG_LEVEL_DEBUG, "%s axis", axis_name[i]);
      if (event->event_mask & POINTER_EVENT_AXIS)
      {
        log_message(LOG_LEVEL_DEBUG, "value %f ", wl_fixed_to_double(event->axes[i].value));
      }
      if (event->event_mask & POINTER_EVENT_AXIS_DISCRETE)
      {
        log_message(LOG_LEVEL_DEBUG, "discrete %d ", event->axes[i].discrete);
      }
      if (event->event_mask & POINTER_EVENT_AXIS_SOURCE)
      {
        log_message(LOG_LEVEL_DEBUG, "via %s ", axis_source[event->axis_source]);
      }
      if (event->event_mask & POINTER_EVENT_AXIS_STOP)
      {
        log_message(LOG_LEVEL_INFO, "pointer axis event: (stopped) ");
      }
    }
  }

  memset(event, 0, sizeof(*event));
}

static const struct wl_pointer_listener wl_pointer_listener = {
  .enter         = wl_pointer_enter,
  .leave         = wl_pointer_leave,
  .motion        = wl_pointer_motion,
  .button        = wl_pointer_button,
  .axis          = wl_pointer_axis,
  .frame         = wl_pointer_frame,
  .axis_source   = wl_pointer_axis_source,
  .axis_stop     = wl_pointer_axis_stop,
  .axis_discrete = wl_pointer_axis_discrete,
};

#endif