/*
 * 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, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

/** \file
 * \ingroup wm
 *
 * \name Window-Manager XR Operators
 *
 * Collection of XR-related operators.
 */

#include "BLI_kdopbvh.h"
#include "BLI_listbase.h"
#include "BLI_math.h"

#include "BKE_context.h"
#include "BKE_global.h"
#include "BKE_idprop.h"
#include "BKE_main.h"
#include "BKE_screen.h"

#include "DEG_depsgraph.h"

#include "ED_screen.h"
#include "ED_space_api.h"
#include "ED_transform_snap_object_context.h"
#include "ED_view3d.h"

#include "GHOST_Types.h"

#include "GPU_immediate.h"

#include "MEM_guardedalloc.h"

#include "PIL_time.h"

#include "RNA_access.h"
#include "RNA_define.h"

#include "WM_api.h"
#include "WM_types.h"

#include "wm_xr_intern.h"

/* -------------------------------------------------------------------- */
/** \name Operator Conditions
 * \{ */

/* op->poll */
static bool wm_xr_operator_sessionactive(bContext *C)
{
  wmWindowManager *wm = CTX_wm_manager(C);
  return WM_xr_session_is_ready(&wm->xr);
}

static bool wm_xr_operator_test_event(const wmOperator *op, const wmEvent *event)
{
  if (event->type != EVT_XR_ACTION) {
    return false;
  }

  BLI_assert(event->custom == EVT_DATA_XR);
  BLI_assert(event->customdata);

  wmXrActionData *actiondata = event->customdata;
  return (actiondata->ot == op->type &&
          IDP_EqualsProperties(actiondata->op_properties, op->properties));
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Session Toggle
 *
 * Toggles an XR session, creating an XR context if necessary.
 * \{ */

static void wm_xr_session_update_screen(Main *bmain, const wmXrData *xr_data)
{
  const bool session_exists = WM_xr_session_exists(xr_data);

  for (bScreen *screen = bmain->screens.first; screen; screen = screen->id.next) {
    LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
      LISTBASE_FOREACH (SpaceLink *, slink, &area->spacedata) {
        if (slink->spacetype == SPACE_VIEW3D) {
          View3D *v3d = (View3D *)slink;

          if (v3d->flag & V3D_XR_SESSION_MIRROR) {
            ED_view3d_xr_mirror_update(area, v3d, session_exists);
          }

          if (session_exists) {
            wmWindowManager *wm = bmain->wm.first;
            const Scene *scene = WM_windows_scene_get_from_screen(wm, screen);

            ED_view3d_xr_shading_update(wm, v3d, scene);
          }
          /* Ensure no 3D View is tagged as session root. */
          else {
            v3d->runtime.flag &= ~V3D_RUNTIME_XR_SESSION_ROOT;
          }
        }
      }
    }
  }

  WM_main_add_notifier(NC_WM | ND_XR_DATA_CHANGED, NULL);
}

static void wm_xr_session_update_screen_on_exit_cb(const wmXrData *xr_data)
{
  /* Just use G_MAIN here, storing main isn't reliable enough on file read or exit. */
  wm_xr_session_update_screen(G_MAIN, xr_data);
}

static int wm_xr_session_toggle_exec(bContext *C, wmOperator *UNUSED(op))
{
  Main *bmain = CTX_data_main(C);
  wmWindowManager *wm = CTX_wm_manager(C);
  wmWindow *win = CTX_wm_window(C);
  View3D *v3d = CTX_wm_view3d(C);

  /* Lazily-create XR context - tries to dynamic-link to the runtime,
   * reading `active_runtime.json`. */
  if (wm_xr_init(wm) == false) {
    return OPERATOR_CANCELLED;
  }

  v3d->runtime.flag |= V3D_RUNTIME_XR_SESSION_ROOT;
  wm_xr_session_toggle(wm, win, wm_xr_session_update_screen_on_exit_cb);
  wm_xr_session_update_screen(bmain, &wm->xr);

  WM_event_add_notifier(C, NC_WM | ND_XR_DATA_CHANGED, NULL);

  return OPERATOR_FINISHED;
}

static void WM_OT_xr_session_toggle(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "Toggle VR Session";
  ot->idname = "WM_OT_xr_session_toggle";
  ot->description =
      "Open a view for use with virtual reality headsets, or close it if already "
      "opened";

  /* callbacks */
  ot->exec = wm_xr_session_toggle_exec;
  ot->poll = ED_operator_view3d_active;

  /* XXX INTERNAL just to hide it from the search menu by default, an Add-on will expose it in the
   * UI instead. Not meant as a permanent solution. */
  ot->flag = OPTYPE_INTERNAL;
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Grab Utilities
 * \{ */

typedef struct XrGrabData {
  float mat_prev[4][4];
  float mat_other_prev[4][4];
  bool bimanual_prev;
  bool loc_lock, locz_lock, rot_lock, rotz_lock, scale_lock;
} XrGrabData;

static void wm_xr_grab_init(wmOperator *op)
{
  BLI_assert(op->customdata == NULL);

  op->customdata = MEM_callocN(sizeof(XrGrabData), __func__);
}

static void wm_xr_grab_uninit(wmOperator *op)
{
  MEM_SAFE_FREE(op->customdata);
}

static void wm_xr_grab_update(wmOperator *op, const wmXrActionData *actiondata)
{
  XrGrabData *data = op->customdata;

  quat_to_mat4(data->mat_prev, actiondata->controller_rot);
  copy_v3_v3(data->mat_prev[3], actiondata->controller_loc);

  if (actiondata->bimanual) {
    quat_to_mat4(data->mat_other_prev, actiondata->controller_rot_other);
    copy_v3_v3(data->mat_other_prev[3], actiondata->controller_loc_other);
    data->bimanual_prev = true;
  }
  else {
    data->bimanual_prev = false;
  }
}

static void orient_mat_z_normalized(float R[4][4], const float z_axis[3])
{
  const float scale = len_v3(R[0]);
  float x_axis[3], y_axis[3];

  cross_v3_v3v3(y_axis, z_axis, R[0]);
  normalize_v3(y_axis);
  mul_v3_v3fl(R[1], y_axis, scale);

  cross_v3_v3v3(x_axis, R[1], z_axis);
  normalize_v3(x_axis);
  mul_v3_v3fl(R[0], x_axis, scale);

  mul_v3_v3fl(R[2], z_axis, scale);
}

static void wm_xr_navlocks_apply(const float nav_mat[4][4],
                                 const float nav_inv[4][4],
                                 bool loc_lock,
                                 bool locz_lock,
                                 bool rotz_lock,
                                 float r_prev[4][4],
                                 float r_curr[4][4])
{
  /* Locked in base pose coordinates. */
  float prev_base[4][4], curr_base[4][4];

  mul_m4_m4m4(prev_base, nav_inv, r_prev);
  mul_m4_m4m4(curr_base, nav_inv, r_curr);

  if (rotz_lock) {
    const float z_axis[3] = {0.0f, 0.0f, 1.0f};
    orient_mat_z_normalized(prev_base, z_axis);
    orient_mat_z_normalized(curr_base, z_axis);
  }

  if (loc_lock) {
    copy_v3_v3(curr_base[3], prev_base[3]);
  }
  else if (locz_lock) {
    curr_base[3][2] = prev_base[3][2];
  }

  mul_m4_m4m4(r_prev, nav_mat, prev_base);
  mul_m4_m4m4(r_curr, nav_mat, curr_base);
}

/**
 * Compute transformation delta for a one-handed grab interaction.
 *
 * \param actiondata: Contains current controller pose in world space.
 * \param data: Contains previous controller pose in world space.
 *
 * The delta is computed as the difference between the current and previous
 * controller poses i.e. delta = curr * prev^-1.
 */
static void wm_xr_grab_compute(const wmXrActionData *actiondata,
                               const XrGrabData *data,
                               const float nav_mat[4][4],
                               const float nav_inv[4][4],
                               bool reverse,
                               float r_delta[4][4])
{
  const bool nav_lock = (nav_mat && nav_inv);
  float prev[4][4], curr[4][4];

  if (!data->rot_lock) {
    copy_m4_m4(prev, data->mat_prev);
    zero_v3(prev[3]);
    quat_to_mat4(curr, actiondata->controller_rot);
  }
  else {
    unit_m4(prev);
    unit_m4(curr);
  }

  if (!data->loc_lock || nav_lock) {
    copy_v3_v3(prev[3], data->mat_prev[3]);
    copy_v3_v3(curr[3], actiondata->controller_loc);
  }

  if (nav_lock) {
    wm_xr_navlocks_apply(
        nav_mat, nav_inv, data->loc_lock, data->locz_lock, data->rotz_lock, prev, curr);
  }

  if (reverse) {
    invert_m4(curr);
    mul_m4_m4m4(r_delta, prev, curr);
  }
  else {
    invert_m4(prev);
    mul_m4_m4m4(r_delta, curr, prev);
  }
}

/**
 * Compute transformation delta for a two-handed (bimanual) grab interaction.
 *
 * \param actiondata: Contains current controller poses in world space.
 * \param data: Contains previous controller poses in world space.
 *
 * The delta is computed as the difference (delta = curr * prev^-1) between the current
 * and previous transformations, where the transformations themselves are determined as follows:
 * - Translation: Averaged controller positions.
 * - Rotation: Rotation of axis line between controllers.
 * - Scale: Distance between controllers.
 */
static void wm_xr_grab_compute_bimanual(const wmXrActionData *actiondata,
                                        const XrGrabData *data,
                                        const float nav_mat[4][4],
                                        const float nav_inv[4][4],
                                        bool reverse,
                                        float r_delta[4][4])
{
  const bool nav_lock = (nav_mat && nav_inv);
  float prev[4][4], curr[4][4];
  unit_m4(prev);
  unit_m4(curr);

  if (!data->rot_lock) {
    /* Rotation. */
    float x_axis_prev[3], x_axis_curr[3], y_axis_prev[3], y_axis_curr[3], z_axis_prev[3],
        z_axis_curr[3];
    float m0[3][3], m1[3][3];
    quat_to_mat3(m0, actiondata->controller_rot);
    quat_to_mat3(m1, actiondata->controller_rot_other);

    /* x-axis is the base line between the two controllers. */
    sub_v3_v3v3(x_axis_prev, data->mat_prev[3], data->mat_other_prev[3]);
    sub_v3_v3v3(x_axis_curr, actiondata->controller_loc, actiondata->controller_loc_other);
    /* y-axis is the average of the controllers' y-axes. */
    add_v3_v3v3(y_axis_prev, data->mat_prev[1], data->mat_other_prev[1]);
    mul_v3_fl(y_axis_prev, 0.5f);
    add_v3_v3v3(y_axis_curr, m0[1], m1[1]);
    mul_v3_fl(y_axis_curr, 0.5f);
    /* z-axis is the cross product of the two. */
    cross_v3_v3v3(z_axis_prev, x_axis_prev, y_axis_prev);
    cross_v3_v3v3(z_axis_curr, x_axis_curr, y_axis_curr);
    /* Fix the y-axis to be orthogonal. */
    cross_v3_v3v3(y_axis_prev, z_axis_prev, x_axis_prev);
    cross_v3_v3v3(y_axis_curr, z_axis_curr, x_axis_curr);
    /* Normalize. */
    normalize_v3_v3(prev[0], x_axis_prev);
    normalize_v3_v3(prev[1], y_axis_prev);
    normalize_v3_v3(prev[2], z_axis_prev);
    normalize_v3_v3(curr[0], x_axis_curr);
    normalize_v3_v3(curr[1], y_axis_curr);
    normalize_v3_v3(curr[2], z_axis_curr);
  }

  if (!data->loc_lock || nav_lock) {
    /* Translation: translation of the averaged controller locations. */
    add_v3_v3v3(prev[3], data->mat_prev[3], data->mat_other_prev[3]);
    mul_v3_fl(prev[3], 0.5f);
    add_v3_v3v3(curr[3], actiondata->controller_loc, actiondata->controller_loc_other);
    mul_v3_fl(curr[3], 0.5f);
  }

  if (!data->scale_lock) {
    /* Scaling: distance between controllers. */
    float scale, v[3];

    sub_v3_v3v3(v, data->mat_prev[3], data->mat_other_prev[3]);
    scale = len_v3(v);
    mul_v3_fl(prev[0], scale);
    mul_v3_fl(prev[1], scale);
    mul_v3_fl(prev[2], scale);

    sub_v3_v3v3(v, actiondata->controller_loc, actiondata->controller_loc_other);
    scale = len_v3(v);
    mul_v3_fl(curr[0], scale);
    mul_v3_fl(curr[1], scale);
    mul_v3_fl(curr[2], scale);
  }

  if (nav_lock) {
    wm_xr_navlocks_apply(
        nav_mat, nav_inv, data->loc_lock, data->locz_lock, data->rotz_lock, prev, curr);
  }

  if (reverse) {
    invert_m4(curr);
    mul_m4_m4m4(r_delta, prev, curr);
  }
  else {
    invert_m4(prev);
    mul_m4_m4m4(r_delta, curr, prev);
  }
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Navigation Grab
 *
 * Navigates the scene by grabbing with XR controllers.
 * \{ */

static int wm_xr_navigation_grab_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  const wmXrActionData *actiondata = event->customdata;

  wm_xr_grab_init(op);
  wm_xr_grab_update(op, actiondata);

  WM_event_add_modal_handler(C, op);

  return OPERATOR_RUNNING_MODAL;
}

static int wm_xr_navigation_grab_exec(bContext *UNUSED(C), wmOperator *UNUSED(op))
{
  return OPERATOR_CANCELLED;
}

static bool wm_xr_navigation_grab_can_do_bimanual(const wmXrActionData *actiondata,
                                                  const XrGrabData *data)
{
  /* Returns true if: 1) Bimanual interaction is currently occurring (i.e. inputs on both
   * controllers are pressed) and 2) bimanual interaction occurred on the last update. This second
   * part is needed to avoid "jumpy" navigation changes when transitioning from one-handed to
   * two-handed interaction (see #wm_xr_grab_compute/compute_bimanual() for how navigation deltas
   * are calculated). */
  return (actiondata->bimanual && data->bimanual_prev);
}

static bool wm_xr_navigation_grab_is_bimanual_ending(const wmXrActionData *actiondata,
                                                     const XrGrabData *data)
{
  return (!actiondata->bimanual && data->bimanual_prev);
}

static bool wm_xr_navigation_grab_is_locked(const XrGrabData *data, const bool bimanual)
{
  if (bimanual) {
    return data->loc_lock && data->rot_lock && data->scale_lock;
  }
  /* Ignore scale lock, as one-handed interaction cannot change navigation scale. */
  return data->loc_lock && data->rot_lock;
}

static void wm_xr_navigation_grab_apply(wmXrData *xr,
                                        const wmXrActionData *actiondata,
                                        const XrGrabData *data,
                                        bool bimanual)
{
  GHOST_XrPose nav_pose;
  float nav_scale;
  float nav_mat[4][4], nav_inv[4][4], delta[4][4], out[4][4];

  const bool need_navinv = (data->loc_lock || data->locz_lock || data->rotz_lock);

  WM_xr_session_state_nav_location_get(xr, nav_pose.position);
  WM_xr_session_state_nav_rotation_get(xr, nav_pose.orientation_quat);
  WM_xr_session_state_nav_scale_get(xr, &nav_scale);

  wm_xr_pose_scale_to_mat(&nav_pose, nav_scale, nav_mat);
  if (need_navinv) {
    wm_xr_pose_scale_to_imat(&nav_pose, nav_scale, nav_inv);
  }

  if (bimanual) {
    wm_xr_grab_compute_bimanual(
        actiondata, data, need_navinv ? nav_mat : NULL, need_navinv ? nav_inv : NULL, true, delta);
  }
  else {
    wm_xr_grab_compute(
        actiondata, data, need_navinv ? nav_mat : NULL, need_navinv ? nav_inv : NULL, true, delta);
  }

  mul_m4_m4m4(out, delta, nav_mat);

  /* Limit scale to reasonable values. */
  nav_scale = len_v3(out[0]);

  if (!(nav_scale < xr->session_settings.clip_start ||
        nav_scale > xr->session_settings.clip_end)) {
    WM_xr_session_state_nav_location_set(xr, out[3]);
    if (!data->rot_lock) {
      mat4_to_quat(nav_pose.orientation_quat, out);
      normalize_qt(nav_pose.orientation_quat);
      WM_xr_session_state_nav_rotation_set(xr, nav_pose.orientation_quat);
    }
    if (!data->scale_lock && bimanual) {
      WM_xr_session_state_nav_scale_set(xr, nav_scale);
    }
  }
}

static void wm_xr_navigation_grab_bimanual_state_update(const wmXrActionData *actiondata,
                                                        XrGrabData *data)
{
  if (actiondata->bimanual) {
    if (!data->bimanual_prev) {
      quat_to_mat4(data->mat_prev, actiondata->controller_rot);
      copy_v3_v3(data->mat_prev[3], actiondata->controller_loc);
      quat_to_mat4(data->mat_other_prev, actiondata->controller_rot_other);
      copy_v3_v3(data->mat_other_prev[3], actiondata->controller_loc_other);
    }
    data->bimanual_prev = true;
  }
  else {
    if (data->bimanual_prev) {
      quat_to_mat4(data->mat_prev, actiondata->controller_rot);
      copy_v3_v3(data->mat_prev[3], actiondata->controller_loc);
    }
    data->bimanual_prev = false;
  }
}

static int wm_xr_navigation_grab_modal(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  const wmXrActionData *actiondata = event->customdata;
  XrGrabData *data = op->customdata;
  wmWindowManager *wm = CTX_wm_manager(C);
  wmXrData *xr = &wm->xr;

  const bool do_bimanual = wm_xr_navigation_grab_can_do_bimanual(actiondata, data);

  data->loc_lock = RNA_boolean_get(op->ptr, "lock_location");
  data->locz_lock = RNA_boolean_get(op->ptr, "lock_location_z");
  data->rot_lock = RNA_boolean_get(op->ptr, "lock_rotation");
  data->rotz_lock = RNA_boolean_get(op->ptr, "lock_rotation_z");
  data->scale_lock = RNA_boolean_get(op->ptr, "lock_scale");

  /* Check if navigation is locked. */
  if (!wm_xr_navigation_grab_is_locked(data, do_bimanual)) {
    /* Prevent unwanted snapping (i.e. "jumpy" navigation changes when transitioning from
     * two-handed to one-handed interaction) at the end of a bimanual interaction. */
    if (!wm_xr_navigation_grab_is_bimanual_ending(actiondata, data)) {
      wm_xr_navigation_grab_apply(xr, actiondata, data, do_bimanual);
    }
  }

  wm_xr_navigation_grab_bimanual_state_update(actiondata, data);

  /* NOTE: #KM_PRESS and #KM_RELEASE are the only two values supported by XR events during event
   * dispatching (see #wm_xr_session_action_states_interpret()). For modal XR operators, modal
   * handling starts when an input is "pressed" (action state exceeds the action threshold) and
   * ends when the input is "released" (state falls below the threshold). */
  switch (event->val) {
    case KM_PRESS:
      return OPERATOR_RUNNING_MODAL;
    case KM_RELEASE:
      wm_xr_grab_uninit(op);
      return OPERATOR_FINISHED;
    default:
      BLI_assert_unreachable();
      wm_xr_grab_uninit(op);
      return OPERATOR_CANCELLED;
  }
}

static void WM_OT_xr_navigation_grab(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "XR Navigation Grab";
  ot->idname = "WM_OT_xr_navigation_grab";
  ot->description = "Navigate the VR scene by grabbing with controllers";

  /* callbacks */
  ot->invoke = wm_xr_navigation_grab_invoke;
  ot->exec = wm_xr_navigation_grab_exec;
  ot->modal = wm_xr_navigation_grab_modal;
  ot->poll = wm_xr_operator_sessionactive;

  /* properties */
  RNA_def_boolean(
      ot->srna, "lock_location", false, "Lock Location", "Prevent changes to viewer location");
  RNA_def_boolean(
      ot->srna, "lock_location_z", false, "Lock Elevation", "Prevent changes to viewer elevation");
  RNA_def_boolean(
      ot->srna, "lock_rotation", false, "Lock Rotation", "Prevent changes to viewer rotation");
  RNA_def_boolean(ot->srna,
                  "lock_rotation_z",
                  false,
                  "Lock Up Orientation",
                  "Prevent changes to viewer up orientation");
  RNA_def_boolean(ot->srna, "lock_scale", false, "Lock Scale", "Prevent changes to viewer scale");
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Raycast Utilities
 * \{ */

static const float g_xr_default_raycast_axis[3] = {0.0f, 0.0f, -1.0f};
static const float g_xr_default_raycast_color[4] = {0.35f, 0.35f, 1.0f, 1.0f};

typedef struct XrRaycastData {
  bool from_viewer;
  float origin[3];
  float direction[3];
  float end[3];
  float color[4];
  void *draw_handle;
} XrRaycastData;

static void wm_xr_raycast_draw(const bContext *UNUSED(C),
                               ARegion *UNUSED(region),
                               void *customdata)
{
  const XrRaycastData *data = customdata;

  GPUVertFormat *format = immVertexFormat();
  uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 3, GPU_FETCH_FLOAT);

  if (data->from_viewer) {
    immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);
    immUniformColor4fv(data->color);

    GPU_depth_test(GPU_DEPTH_NONE);
    GPU_point_size(7.0f);

    immBegin(GPU_PRIM_POINTS, 1);
    immVertex3fv(pos, data->end);
    immEnd();
  }
  else {
    uint col = GPU_vertformat_attr_add(format, "color", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
    immBindBuiltinProgram(GPU_SHADER_3D_POLYLINE_FLAT_COLOR);

    float viewport[4];
    GPU_viewport_size_get_f(viewport);
    immUniform2fv("viewportSize", &viewport[2]);

    immUniform1f("lineWidth", 3.0f * U.pixelsize);

    GPU_depth_test(GPU_DEPTH_LESS_EQUAL);

    immBegin(GPU_PRIM_LINES, 2);
    immAttrSkip(col);
    immVertex3fv(pos, data->origin);
    immAttr4fv(col, data->color);
    immVertex3fv(pos, data->end);
    immEnd();
  }

  immUnbindProgram();
}

static void wm_xr_raycast_init(wmOperator *op)
{
  BLI_assert(op->customdata == NULL);

  op->customdata = MEM_callocN(sizeof(XrRaycastData), __func__);

  SpaceType *st = BKE_spacetype_from_id(SPACE_VIEW3D);
  if (!st) {
    return;
  }

  ARegionType *art = BKE_regiontype_from_id(st, RGN_TYPE_XR);
  if (!art) {
    return;
  }

  XrRaycastData *data = op->customdata;
  data->draw_handle = ED_region_draw_cb_activate(
      art, wm_xr_raycast_draw, op->customdata, REGION_DRAW_POST_VIEW);
}

static void wm_xr_raycast_uninit(wmOperator *op)
{
  if (!op->customdata) {
    return;
  }

  SpaceType *st = BKE_spacetype_from_id(SPACE_VIEW3D);
  if (st) {
    ARegionType *art = BKE_regiontype_from_id(st, RGN_TYPE_XR);
    if (art) {
      XrRaycastData *data = op->customdata;
      ED_region_draw_cb_exit(art, data->draw_handle);
    }
  }

  MEM_freeN(op->customdata);
}

static void wm_xr_raycast_update(wmOperator *op,
                                 const wmXrData *xr,
                                 const wmXrActionData *actiondata)
{
  XrRaycastData *data = op->customdata;
  float ray_length, axis[3];

  data->from_viewer = RNA_boolean_get(op->ptr, "from_viewer");
  RNA_float_get_array(op->ptr, "axis", axis);
  RNA_float_get_array(op->ptr, "color", data->color);

  if (data->from_viewer) {
    float viewer_rot[4];
    WM_xr_session_state_viewer_pose_location_get(xr, data->origin);
    WM_xr_session_state_viewer_pose_rotation_get(xr, viewer_rot);
    mul_qt_v3(viewer_rot, axis);
    ray_length = (xr->session_settings.clip_start + xr->session_settings.clip_end) / 2.0f;
  }
  else {
    copy_v3_v3(data->origin, actiondata->controller_loc);
    mul_qt_v3(actiondata->controller_rot, axis);
    ray_length = xr->session_settings.clip_end;
  }

  copy_v3_v3(data->direction, axis);
  madd_v3_v3v3fl(data->end, data->origin, data->direction, ray_length);
}

static void wm_xr_raycast(Scene *scene,
                          Depsgraph *depsgraph,
                          const float origin[3],
                          const float direction[3],
                          float *ray_dist,
                          bool selectable_only,
                          float r_location[3],
                          float r_normal[3],
                          int *r_index,
                          Object **r_ob,
                          float r_obmat[4][4])
{
  /* Uses same raycast method as Scene.ray_cast(). */
  SnapObjectContext *sctx = ED_transform_snap_object_context_create(scene, 0);

  ED_transform_snap_object_project_ray_ex(
      sctx,
      depsgraph,
      NULL,
      &(const struct SnapObjectParams){
          .snap_select = (selectable_only ? SNAP_SELECTABLE : SNAP_ALL)},
      origin,
      direction,
      ray_dist,
      r_location,
      r_normal,
      r_index,
      r_ob,
      r_obmat);

  ED_transform_snap_object_context_destroy(sctx);
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Navigation Fly
 *
 * Navigates the scene by moving/turning relative to navigation space or the XR viewer or
 * controller.
 * \{ */

#define XR_DEFAULT_FLY_SPEED_MOVE 0.054f
#define XR_DEFAULT_FLY_SPEED_TURN 0.03f

typedef enum eXrFlyMode {
  XR_FLY_FORWARD = 0,
  XR_FLY_BACK = 1,
  XR_FLY_LEFT = 2,
  XR_FLY_RIGHT = 3,
  XR_FLY_UP = 4,
  XR_FLY_DOWN = 5,
  XR_FLY_TURNLEFT = 6,
  XR_FLY_TURNRIGHT = 7,
  XR_FLY_VIEWER_FORWARD = 8,
  XR_FLY_VIEWER_BACK = 9,
  XR_FLY_VIEWER_LEFT = 10,
  XR_FLY_VIEWER_RIGHT = 11,
  XR_FLY_CONTROLLER_FORWARD = 12,
} eXrFlyMode;

typedef struct XrFlyData {
  float viewer_rot[4];
  double time_prev;
} XrFlyData;

static void wm_xr_fly_init(wmOperator *op, const wmXrData *xr)
{
  BLI_assert(op->customdata == NULL);

  XrFlyData *data = op->customdata = MEM_callocN(sizeof(XrFlyData), __func__);

  WM_xr_session_state_viewer_pose_rotation_get(xr, data->viewer_rot);
  data->time_prev = PIL_check_seconds_timer();
}

static void wm_xr_fly_uninit(wmOperator *op)
{
  MEM_SAFE_FREE(op->customdata);
}

static void wm_xr_fly_compute_move(eXrFlyMode mode,
                                   float speed,
                                   const float ref_quat[4],
                                   const float nav_mat[4][4],
                                   bool locz_lock,
                                   float r_delta[4][4])
{
  float ref_axes[3][3];
  quat_to_mat3(ref_axes, ref_quat);

  unit_m4(r_delta);

  switch (mode) {
    /* Navigation space reference. */
    case XR_FLY_FORWARD:
      madd_v3_v3fl(r_delta[3], ref_axes[1], speed);
      return;
    case XR_FLY_BACK:
      madd_v3_v3fl(r_delta[3], ref_axes[1], -speed);
      return;
    case XR_FLY_LEFT:
      madd_v3_v3fl(r_delta[3], ref_axes[0], -speed);
      return;
    case XR_FLY_RIGHT:
      madd_v3_v3fl(r_delta[3], ref_axes[0], speed);
      return;
    case XR_FLY_UP:
    case XR_FLY_DOWN:
      if (!locz_lock) {
        madd_v3_v3fl(r_delta[3], ref_axes[2], (mode == XR_FLY_UP) ? speed : -speed);
      }
      return;
    /* Viewer/controller space reference. */
    case XR_FLY_VIEWER_FORWARD:
    case XR_FLY_CONTROLLER_FORWARD:
      negate_v3_v3(r_delta[3], ref_axes[2]);
      break;
    case XR_FLY_VIEWER_BACK:
      copy_v3_v3(r_delta[3], ref_axes[2]);
      break;
    case XR_FLY_VIEWER_LEFT:
      negate_v3_v3(r_delta[3], ref_axes[0]);
      break;
    case XR_FLY_VIEWER_RIGHT:
      copy_v3_v3(r_delta[3], ref_axes[0]);
      break;
    /* Unused. */
    case XR_FLY_TURNLEFT:
    case XR_FLY_TURNRIGHT:
      BLI_assert_unreachable();
      return;
  }

  if (locz_lock) {
    /* Lock elevation in navigation space. */
    float z_axis[3], projected[3];

    normalize_v3_v3(z_axis, nav_mat[2]);
    project_v3_v3v3_normalized(projected, r_delta[3], z_axis);
    sub_v3_v3(r_delta[3], projected);

    normalize_v3(r_delta[3]);
  }

  mul_v3_fl(r_delta[3], speed);
}

static void wm_xr_fly_compute_turn(eXrFlyMode mode,
                                   float speed,
                                   const float viewer_mat[4][4],
                                   const float nav_mat[4][4],
                                   const float nav_inv[4][4],
                                   float r_delta[4][4])
{
  BLI_assert(mode == XR_FLY_TURNLEFT || mode == XR_FLY_TURNRIGHT);

  float z_axis[3], m[3][3], prev[4][4], curr[4][4];

  /* Turn around Z-axis in navigation space. */
  normalize_v3_v3(z_axis, nav_mat[2]);
  axis_angle_normalized_to_mat3(m, z_axis, (mode == XR_FLY_TURNLEFT) ? speed : -speed);
  copy_m4_m3(r_delta, m);

  copy_m4_m4(prev, viewer_mat);
  mul_m4_m4m4(curr, r_delta, viewer_mat);

  /* Lock location in base pose space. */
  wm_xr_navlocks_apply(nav_mat, nav_inv, true, false, false, prev, curr);

  invert_m4(prev);
  mul_m4_m4m4(r_delta, curr, prev);
}

static void wm_xr_basenav_rotation_calc(const wmXrData *xr,
                                        const float nav_rotation[4],
                                        float r_rotation[4])
{
  /* Apply nav rotation to base pose Z-rotation. */
  float base_eul[3], base_quatz[4];
  quat_to_eul(base_eul, xr->runtime->session_state.prev_base_pose.orientation_quat);
  axis_angle_to_quat_single(base_quatz, 'Z', base_eul[2]);
  mul_qt_qtqt(r_rotation, nav_rotation, base_quatz);
}

static int wm_xr_navigation_fly_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  wmWindowManager *wm = CTX_wm_manager(C);

  wm_xr_fly_init(op, &wm->xr);

  WM_event_add_modal_handler(C, op);

  return OPERATOR_RUNNING_MODAL;
}

static int wm_xr_navigation_fly_exec(bContext *UNUSED(C), wmOperator *UNUSED(op))
{
  return OPERATOR_CANCELLED;
}

static int wm_xr_navigation_fly_modal(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  if (event->val == KM_RELEASE) {
    wm_xr_fly_uninit(op);
    return OPERATOR_FINISHED;
  }

  const wmXrActionData *actiondata = event->customdata;
  XrFlyData *data = op->customdata;
  wmWindowManager *wm = CTX_wm_manager(C);
  wmXrData *xr = &wm->xr;
  eXrFlyMode mode;
  bool turn, locz_lock, dir_lock, speed_frame_based;
  bool speed_interp_cubic = false;
  float speed, speed_max, speed_p0[2], speed_p1[2];
  GHOST_XrPose nav_pose;
  float nav_mat[4][4], delta[4][4], out[4][4];

  const double time_now = PIL_check_seconds_timer();

  mode = (eXrFlyMode)RNA_enum_get(op->ptr, "mode");
  turn = (ELEM(mode, XR_FLY_TURNLEFT, XR_FLY_TURNRIGHT));

  locz_lock = RNA_boolean_get(op->ptr, "lock_location_z");
  dir_lock = RNA_boolean_get(op->ptr, "lock_direction");
  speed_frame_based = RNA_boolean_get(op->ptr, "speed_frame_based");
  speed = RNA_float_get(op->ptr, "speed_min");
  speed_max = RNA_float_get(op->ptr, "speed_max");

  PropertyRNA *prop = RNA_struct_find_property(op->ptr, "speed_interpolation0");
  if (prop && RNA_property_is_set(op->ptr, prop)) {
    RNA_property_float_get_array(op->ptr, prop, speed_p0);
    speed_interp_cubic = true;
  }
  else {
    speed_p0[0] = speed_p0[1] = 0.0f;
  }

  prop = RNA_struct_find_property(op->ptr, "speed_interpolation1");
  if (prop && RNA_property_is_set(op->ptr, prop)) {
    RNA_property_float_get_array(op->ptr, prop, speed_p1);
    speed_interp_cubic = true;
  }
  else {
    speed_p1[0] = speed_p1[1] = 1.0f;
  }

  /* Ensure valid interpolation. */
  if (speed_max < speed) {
    speed_max = speed;
  }

  /* Interpolate between min/max speeds based on button state. */
  switch (actiondata->type) {
    case XR_BOOLEAN_INPUT:
      speed = speed_max;
      break;
    case XR_FLOAT_INPUT:
    case XR_VECTOR2F_INPUT: {
      float state = (actiondata->type == XR_FLOAT_INPUT) ? fabsf(actiondata->state[0]) :
                                                           len_v2(actiondata->state);
      float speed_t = (actiondata->float_threshold < 1.0f) ?
                          (state - actiondata->float_threshold) /
                              (1.0f - actiondata->float_threshold) :
                          1.0f;
      if (speed_interp_cubic) {
        float start[2], end[2], p[2];

        start[0] = 0.0f;
        start[1] = speed;
        speed_p0[1] = speed + speed_p0[1] * (speed_max - speed);
        speed_p1[1] = speed + speed_p1[1] * (speed_max - speed);
        end[0] = 1.0f;
        end[1] = speed_max;

        interp_v2_v2v2v2v2_cubic(p, start, speed_p0, speed_p1, end, speed_t);
        speed = p[1];
      }
      else {
        speed += speed_t * (speed_max - speed);
      }
      break;
    }
    case XR_POSE_INPUT:
    case XR_VIBRATION_OUTPUT:
      BLI_assert_unreachable();
      break;
  }

  if (!speed_frame_based) {
    /* Adjust speed based on last update time. */
    speed *= time_now - data->time_prev;
  }
  data->time_prev = time_now;

  WM_xr_session_state_nav_location_get(xr, nav_pose.position);
  WM_xr_session_state_nav_rotation_get(xr, nav_pose.orientation_quat);
  wm_xr_pose_to_mat(&nav_pose, nav_mat);

  if (turn) {
    if (dir_lock) {
      unit_m4(delta);
    }
    else {
      GHOST_XrPose viewer_pose;
      float viewer_mat[4][4], nav_inv[4][4];

      WM_xr_session_state_viewer_pose_location_get(xr, viewer_pose.position);
      WM_xr_session_state_viewer_pose_rotation_get(xr, viewer_pose.orientation_quat);
      wm_xr_pose_to_mat(&viewer_pose, viewer_mat);
      wm_xr_pose_to_imat(&nav_pose, nav_inv);

      wm_xr_fly_compute_turn(mode, speed, viewer_mat, nav_mat, nav_inv, delta);
    }
  }
  else {
    float nav_scale, ref_quat[4];

    /* Adjust speed for base and navigation scale. */
    WM_xr_session_state_nav_scale_get(xr, &nav_scale);
    speed *= xr->session_settings.base_scale * nav_scale;

    switch (mode) {
      /* Move relative to navigation space. */
      case XR_FLY_FORWARD:
      case XR_FLY_BACK:
      case XR_FLY_LEFT:
      case XR_FLY_RIGHT:
      case XR_FLY_UP:
      case XR_FLY_DOWN:
        wm_xr_basenav_rotation_calc(xr, nav_pose.orientation_quat, ref_quat);
        break;
      /* Move relative to viewer. */
      case XR_FLY_VIEWER_FORWARD:
      case XR_FLY_VIEWER_BACK:
      case XR_FLY_VIEWER_LEFT:
      case XR_FLY_VIEWER_RIGHT:
        if (dir_lock) {
          copy_qt_qt(ref_quat, data->viewer_rot);
        }
        else {
          WM_xr_session_state_viewer_pose_rotation_get(xr, ref_quat);
        }
        break;
      /* Move relative to controller. */
      case XR_FLY_CONTROLLER_FORWARD:
        copy_qt_qt(ref_quat, actiondata->controller_rot);
        break;
      /* Unused. */
      case XR_FLY_TURNLEFT:
      case XR_FLY_TURNRIGHT:
        BLI_assert_unreachable();
        break;
    }

    wm_xr_fly_compute_move(mode, speed, ref_quat, nav_mat, locz_lock, delta);
  }

  mul_m4_m4m4(out, delta, nav_mat);

  WM_xr_session_state_nav_location_set(xr, out[3]);
  if (turn) {
    mat4_to_quat(nav_pose.orientation_quat, out);
    WM_xr_session_state_nav_rotation_set(xr, nav_pose.orientation_quat);
  }

  if (event->val == KM_PRESS) {
    return OPERATOR_RUNNING_MODAL;
  }

  /* XR events currently only support press and release. */
  BLI_assert_unreachable();
  wm_xr_fly_uninit(op);
  return OPERATOR_CANCELLED;
}

static void WM_OT_xr_navigation_fly(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "XR Navigation Fly";
  ot->idname = "WM_OT_xr_navigation_fly";
  ot->description = "Move/turn relative to the VR viewer or controller";

  /* callbacks */
  ot->invoke = wm_xr_navigation_fly_invoke;
  ot->exec = wm_xr_navigation_fly_exec;
  ot->modal = wm_xr_navigation_fly_modal;
  ot->poll = wm_xr_operator_sessionactive;

  /* properties */
  static const EnumPropertyItem fly_modes[] = {
      {XR_FLY_FORWARD, "FORWARD", 0, "Forward", "Move along navigation forward axis"},
      {XR_FLY_BACK, "BACK", 0, "Back", "Move along navigation back axis"},
      {XR_FLY_LEFT, "LEFT", 0, "Left", "Move along navigation left axis"},
      {XR_FLY_RIGHT, "RIGHT", 0, "Right", "Move along navigation right axis"},
      {XR_FLY_UP, "UP", 0, "Up", "Move along navigation up axis"},
      {XR_FLY_DOWN, "DOWN", 0, "Down", "Move along navigation down axis"},
      {XR_FLY_TURNLEFT,
       "TURNLEFT",
       0,
       "Turn Left",
       "Turn counter-clockwise around navigation up axis"},
      {XR_FLY_TURNRIGHT, "TURNRIGHT", 0, "Turn Right", "Turn clockwise around navigation up axis"},
      {XR_FLY_VIEWER_FORWARD,
       "VIEWER_FORWARD",
       0,
       "Viewer Forward",
       "Move along viewer's forward axis"},
      {XR_FLY_VIEWER_BACK, "VIEWER_BACK", 0, "Viewer Back", "Move along viewer's back axis"},
      {XR_FLY_VIEWER_LEFT, "VIEWER_LEFT", 0, "Viewer Left", "Move along viewer's left axis"},
      {XR_FLY_VIEWER_RIGHT, "VIEWER_RIGHT", 0, "Viewer Right", "Move along viewer's right axis"},
      {XR_FLY_CONTROLLER_FORWARD,
       "CONTROLLER_FORWARD",
       0,
       "Controller Forward",
       "Move along controller's forward axis"},
      {0, NULL, 0, NULL, NULL},
  };

  static const float default_speed_p0[2] = {0.0f, 0.0f};
  static const float default_speed_p1[2] = {1.0f, 1.0f};

  RNA_def_enum(ot->srna, "mode", fly_modes, XR_FLY_VIEWER_FORWARD, "Mode", "Fly mode");
  RNA_def_boolean(
      ot->srna, "lock_location_z", false, "Lock Elevation", "Prevent changes to viewer elevation");
  RNA_def_boolean(ot->srna,
                  "lock_direction",
                  false,
                  "Lock Direction",
                  "Limit movement to viewer's initial direction");
  RNA_def_boolean(ot->srna,
                  "speed_frame_based",
                  true,
                  "Frame Based Speed",
                  "Apply fixed movement deltas every update");
  RNA_def_float(ot->srna,
                "speed_min",
                XR_DEFAULT_FLY_SPEED_MOVE / 3.0f,
                0.0f,
                1000.0f,
                "Minimum Speed",
                "Minimum move (turn) speed in meters (radians) per second or frame",
                0.0f,
                1000.0f);
  RNA_def_float(ot->srna,
                "speed_max",
                XR_DEFAULT_FLY_SPEED_MOVE,
                0.0f,
                1000.0f,
                "Maximum Speed",
                "Maximum move (turn) speed in meters (radians) per second or frame",
                0.0f,
                1000.0f);
  RNA_def_float_vector(ot->srna,
                       "speed_interpolation0",
                       2,
                       default_speed_p0,
                       0.0f,
                       1.0f,
                       "Speed Interpolation 0",
                       "First cubic spline control point between min/max speeds",
                       0.0f,
                       1.0f);
  RNA_def_float_vector(ot->srna,
                       "speed_interpolation1",
                       2,
                       default_speed_p1,
                       0.0f,
                       1.0f,
                       "Speed Interpolation 1",
                       "Second cubic spline control point between min/max speeds",
                       0.0f,
                       1.0f);
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Navigation Teleport
 *
 * Casts a ray from an XR controller's pose and teleports to any hit geometry.
 * \{ */

static void wm_xr_navigation_teleport(bContext *C,
                                      wmXrData *xr,
                                      const float origin[3],
                                      const float direction[3],
                                      float *ray_dist,
                                      bool selectable_only,
                                      const bool teleport_axes[3],
                                      float teleport_t,
                                      float teleport_ofs)
{
  Scene *scene = CTX_data_scene(C);
  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
  float location[3];
  float normal[3];
  int index;
  Object *ob = NULL;
  float obmat[4][4];

  wm_xr_raycast(scene,
                depsgraph,
                origin,
                direction,
                ray_dist,
                selectable_only,
                location,
                normal,
                &index,
                &ob,
                obmat);

  /* Teleport. */
  if (ob) {
    float nav_location[3], nav_rotation[4], viewer_location[3];
    float nav_axes[3][3], projected[3], v0[3], v1[3];
    float out[3] = {0.0f, 0.0f, 0.0f};

    WM_xr_session_state_nav_location_get(xr, nav_location);
    WM_xr_session_state_nav_rotation_get(xr, nav_rotation);
    WM_xr_session_state_viewer_pose_location_get(xr, viewer_location);

    wm_xr_basenav_rotation_calc(xr, nav_rotation, nav_rotation);
    quat_to_mat3(nav_axes, nav_rotation);

    /* Project locations onto navigation axes. */
    for (int a = 0; a < 3; ++a) {
      project_v3_v3v3_normalized(projected, nav_location, nav_axes[a]);
      if (teleport_axes[a]) {
        /* Interpolate between projected locations. */
        project_v3_v3v3_normalized(v0, location, nav_axes[a]);
        project_v3_v3v3_normalized(v1, viewer_location, nav_axes[a]);
        sub_v3_v3(v0, v1);
        madd_v3_v3fl(projected, v0, teleport_t);
        /* Subtract offset. */
        project_v3_v3v3_normalized(v0, normal, nav_axes[a]);
        madd_v3_v3fl(projected, v0, teleport_ofs);
      }
      /* Add to final location. */
      add_v3_v3(out, projected);
    }

    WM_xr_session_state_nav_location_set(xr, out);
  }
}

static int wm_xr_navigation_teleport_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  wm_xr_raycast_init(op);

  int retval = op->type->modal(C, op, event);

  if ((retval & OPERATOR_RUNNING_MODAL) != 0) {
    WM_event_add_modal_handler(C, op);
  }

  return retval;
}

static int wm_xr_navigation_teleport_exec(bContext *UNUSED(C), wmOperator *UNUSED(op))
{
  return OPERATOR_CANCELLED;
}

static int wm_xr_navigation_teleport_modal(bContext *C, wmOperator *op, const wmEvent *event)
{
  if (!wm_xr_operator_test_event(op, event)) {
    return OPERATOR_PASS_THROUGH;
  }

  const wmXrActionData *actiondata = event->customdata;
  wmWindowManager *wm = CTX_wm_manager(C);
  wmXrData *xr = &wm->xr;

  wm_xr_raycast_update(op, xr, actiondata);

  switch (event->val) {
    case KM_PRESS:
      return OPERATOR_RUNNING_MODAL;
    case KM_RELEASE: {
      XrRaycastData *data = op->customdata;
      bool selectable_only, teleport_axes[3];
      float teleport_t, teleport_ofs, ray_dist;

      RNA_boolean_get_array(op->ptr, "teleport_axes", teleport_axes);
      teleport_t = RNA_float_get(op->ptr, "interpolation");
      teleport_ofs = RNA_float_get(op->ptr, "offset");
      selectable_only = RNA_boolean_get(op->ptr, "selectable_only");
      ray_dist = RNA_float_get(op->ptr, "distance");

      wm_xr_navigation_teleport(C,
                                xr,
                                data->origin,
                                data->direction,
                                &ray_dist,
                                selectable_only,
                                teleport_axes,
                                teleport_t,
                                teleport_ofs);

      wm_xr_raycast_uninit(op);

      return OPERATOR_FINISHED;
    }
    default:
      /* XR events currently only support press and release. */
      BLI_assert_unreachable();
      wm_xr_raycast_uninit(op);
      return OPERATOR_CANCELLED;
  }
}

static void WM_OT_xr_navigation_teleport(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "XR Navigation Teleport";
  ot->idname = "WM_OT_xr_navigation_teleport";
  ot->description = "Set VR viewer location to controller raycast hit location";

  /* callbacks */
  ot->invoke = wm_xr_navigation_teleport_invoke;
  ot->exec = wm_xr_navigation_teleport_exec;
  ot->modal = wm_xr_navigation_teleport_modal;
  ot->poll = wm_xr_operator_sessionactive;

  /* properties */
  static bool default_teleport_axes[3] = {true, true, true};

  RNA_def_boolean_vector(ot->srna,
                         "teleport_axes",
                         3,
                         default_teleport_axes,
                         "Teleport Axes",
                         "Enabled teleport axes in navigation space");
  RNA_def_float(ot->srna,
                "interpolation",
                1.0f,
                0.0f,
                1.0f,
                "Interpolation",
                "Interpolation factor between viewer and hit locations",
                0.0f,
                1.0f);
  RNA_def_float(ot->srna,
                "offset",
                0.0f,
                0.0f,
                FLT_MAX,
                "Offset",
                "Offset along hit normal to subtract from final location",
                0.0f,
                FLT_MAX);
  RNA_def_boolean(ot->srna,
                  "selectable_only",
                  true,
                  "Selectable Only",
                  "Only allow selectable objects to influence raycast result");
  RNA_def_float(ot->srna,
                "distance",
                BVH_RAYCAST_DIST_MAX,
                0.0,
                BVH_RAYCAST_DIST_MAX,
                "",
                "Maximum raycast distance",
                0.0,
                BVH_RAYCAST_DIST_MAX);
  RNA_def_boolean(
      ot->srna, "from_viewer", false, "From Viewer", "Use viewer pose as raycast origin");
  RNA_def_float_vector(ot->srna,
                       "axis",
                       3,
                       g_xr_default_raycast_axis,
                       -1.0f,
                       1.0f,
                       "Axis",
                       "Raycast axis in controller/viewer space",
                       -1.0f,
                       1.0f);
  RNA_def_float_color(ot->srna,
                      "color",
                      4,
                      g_xr_default_raycast_color,
                      0.0f,
                      1.0f,
                      "Color",
                      "Raycast color",
                      0.0f,
                      1.0f);
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name XR Navigation Reset
 *
 * Resets XR navigation deltas relative to session base pose.
 * \{ */

static int wm_xr_navigation_reset_exec(bContext *C, wmOperator *op)
{
  wmWindowManager *wm = CTX_wm_manager(C);
  wmXrData *xr = &wm->xr;
  bool reset_loc, reset_rot, reset_scale;

  reset_loc = RNA_boolean_get(op->ptr, "location");
  reset_rot = RNA_boolean_get(op->ptr, "rotation");
  reset_scale = RNA_boolean_get(op->ptr, "scale");

  if (reset_loc) {
    float loc[3];
    if (!reset_scale) {
      float nav_rotation[4], nav_scale;

      WM_xr_session_state_nav_rotation_get(xr, nav_rotation);
      WM_xr_session_state_nav_scale_get(xr, &nav_scale);

      /* Adjust location based on scale. */
      mul_v3_v3fl(loc, xr->runtime->session_state.prev_base_pose.position, nav_scale);
      sub_v3_v3(loc, xr->runtime->session_state.prev_base_pose.position);
      mul_qt_v3(nav_rotation, loc);
      negate_v3(loc);
    }
    else {
      zero_v3(loc);
    }
    WM_xr_session_state_nav_location_set(xr, loc);
  }

  if (reset_rot) {
    float rot[4];
    unit_qt(rot);
    WM_xr_session_state_nav_rotation_set(xr, rot);
  }

  if (reset_scale) {
    if (!reset_loc) {
      float nav_location[3], nav_rotation[4], nav_scale;
      float nav_axes[3][3], v[3];

      WM_xr_session_state_nav_location_get(xr, nav_location);
      WM_xr_session_state_nav_rotation_get(xr, nav_rotation);
      WM_xr_session_state_nav_scale_get(xr, &nav_scale);

      /* Offset any location changes when changing scale. */
      mul_v3_v3fl(v, xr->runtime->session_state.prev_base_pose.position, nav_scale);
      sub_v3_v3(v, xr->runtime->session_state.prev_base_pose.position);
      mul_qt_v3(nav_rotation, v);
      add_v3_v3(nav_location, v);

      /* Reset elevation to base pose value. */
      quat_to_mat3(nav_axes, nav_rotation);
      project_v3_v3v3_normalized(v, nav_location, nav_axes[2]);
      sub_v3_v3(nav_location, v);

      WM_xr_session_state_nav_location_set(xr, nav_location);
    }
    WM_xr_session_state_nav_scale_set(xr, 1.0f);
  }

  return OPERATOR_FINISHED;
}

static void WM_OT_xr_navigation_reset(wmOperatorType *ot)
{
  /* identifiers */
  ot->name = "XR Navigation Reset";
  ot->idname = "WM_OT_xr_navigation_reset";
  ot->description = "Reset VR navigation deltas relative to session base pose";

  /* callbacks */
  ot->exec = wm_xr_navigation_reset_exec;
  ot->poll = wm_xr_operator_sessionactive;

  /* properties */
  RNA_def_boolean(ot->srna, "location", true, "Location", "Reset location deltas");
  RNA_def_boolean(ot->srna, "rotation", true, "Rotation", "Reset rotation deltas");
  RNA_def_boolean(ot->srna, "scale", true, "Scale", "Reset scale deltas");
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name Operator Registration
 * \{ */

void wm_xr_operatortypes_register(void)
{
  WM_operatortype_append(WM_OT_xr_session_toggle);
  WM_operatortype_append(WM_OT_xr_navigation_grab);
  WM_operatortype_append(WM_OT_xr_navigation_fly);
  WM_operatortype_append(WM_OT_xr_navigation_teleport);
  WM_operatortype_append(WM_OT_xr_navigation_reset);
}

/** \} */
