// Copyright 2018-2022, Collabora, Ltd.
// SPDX-License-Identifier: BSL-1.0
/*!
 * @file
 * @brief  Holds input related functions.
 * @author Jakob Bornecrantz <jakob@collabora.com>
 * @ingroup oxr_main
 */

#include "util/u_debug.h"
#include "util/u_time.h"
#include "util/u_misc.h"

#include "xrt/xrt_compiler.h"

#include "oxr_objects.h"
#include "oxr_logger.h"
#include "oxr_handle.h"
#include "oxr_two_call.h"
#include "oxr_input_transform.h"
#include "oxr_subaction.h"

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>


/*
 *
 * Pre declare functions.
 *
 */

static void
oxr_session_get_action_set_attachment(struct oxr_session *sess,
                                      XrActionSet actionSet,
                                      struct oxr_action_set_attachment **act_set_attached,
                                      struct oxr_action_set **act_set);

static void
oxr_session_get_action_attachment(struct oxr_session *sess,
                                  uint32_t act_key,
                                  struct oxr_action_attachment **out_act_attached);

static void
oxr_action_cache_update(struct oxr_logger *log,
                        struct oxr_session *sess,
                        uint32_t countActionSets,
                        const XrActiveActionSet *actionSets,
                        struct oxr_action_attachment *act_attached,
                        struct oxr_action_cache *cache,
                        int64_t time,
                        struct oxr_subaction_paths *subaction_path,
                        bool select);

static void
oxr_action_attachment_update(struct oxr_logger *log,
                             struct oxr_session *sess,
                             uint32_t countActionSets,
                             const XrActiveActionSet *actionSets,
                             struct oxr_action_attachment *act_attached,
                             int64_t time,
                             struct oxr_subaction_paths subaction_paths);

static void
oxr_action_bind_io(struct oxr_logger *log,
                   struct oxr_sink_logger *slog,
                   struct oxr_session *sess,
                   struct oxr_action *act,
                   struct oxr_action_cache *cache,
                   struct oxr_interaction_profile *profile,
                   enum oxr_subaction_path subaction_path);

/*
 *
 * Action attachment functions
 *
 */

/*!
 * De-initialize/de-allocate all dynamic members of @ref oxr_action_cache
 * @private @memberof oxr_action_cache
 */
static void
oxr_action_cache_teardown(struct oxr_action_cache *cache)
{
	// Clean up input transforms
	for (uint32_t i = 0; i < cache->input_count; i++) {
		struct oxr_action_input *action_input = &cache->inputs[i];
		oxr_input_transform_destroy(&(action_input->transforms));
		action_input->transform_count = 0;
	}
	free(cache->inputs);
	cache->inputs = NULL;
	free(cache->outputs);
	cache->outputs = NULL;
}

/*!
 * Tear down an action attachment struct.
 *
 * Does not deallocate the struct itself.
 *
 * @public @memberof oxr_action_attachment
 */
static void
oxr_action_attachment_teardown(struct oxr_action_attachment *act_attached)
{
	struct oxr_session *sess = act_attached->sess;
	u_hashmap_int_erase(sess->act_attachments_by_key, act_attached->act_key);

#define CACHE_TEARDOWN(X) oxr_action_cache_teardown(&(act_attached->X));
	OXR_FOR_EACH_SUBACTION_PATH(CACHE_TEARDOWN)
#undef CACHE_TEARDOWN

	// Unref this action's refcounted data
	oxr_refcounted_unref(&act_attached->act_ref->base);
}

/*!
 * Set up an action attachment struct.
 *
 * @public @memberof oxr_action_attachment
 */
static XrResult
oxr_action_attachment_init(struct oxr_logger *log,
                           struct oxr_action_set_attachment *act_set_attached,
                           struct oxr_action_attachment *act_attached,
                           struct oxr_action *act)
{
	struct oxr_session *sess = act_set_attached->sess;
	act_attached->sess = sess;
	act_attached->act_set_attached = act_set_attached;
	u_hashmap_int_insert(sess->act_attachments_by_key, act->act_key, act_attached);

	// Reference this action's refcounted data
	act_attached->act_ref = act->data;
	oxr_refcounted_ref(&act_attached->act_ref->base);

	// Copy this for efficiency.
	act_attached->act_key = act->act_key;
	return XR_SUCCESS;
}


/*
 *
 * Action set attachment functions
 *
 */

/*!
 * @public @memberof oxr_action_set_attachment
 */
static XrResult
oxr_action_set_attachment_init(struct oxr_logger *log,
                               struct oxr_session *sess,
                               struct oxr_action_set *act_set,
                               struct oxr_action_set_attachment *act_set_attached)
{
	act_set_attached->sess = sess;

	// Reference this action set's refcounted data
	act_set_attached->act_set_ref = act_set->data;
	oxr_refcounted_ref(&act_set_attached->act_set_ref->base);

	u_hashmap_int_insert(sess->act_sets_attachments_by_key, act_set->act_set_key, act_set_attached);

	// Copy this for efficiency.
	act_set_attached->act_set_key = act_set->act_set_key;

	return XR_SUCCESS;
}

void
oxr_action_set_attachment_teardown(struct oxr_action_set_attachment *act_set_attached)
{
	for (size_t i = 0; i < act_set_attached->action_attachment_count; ++i) {
		oxr_action_attachment_teardown(&(act_set_attached->act_attachments[i]));
	}
	free(act_set_attached->act_attachments);
	act_set_attached->act_attachments = NULL;
	act_set_attached->action_attachment_count = 0;

	struct oxr_session *sess = act_set_attached->sess;
	u_hashmap_int_erase(sess->act_sets_attachments_by_key, act_set_attached->act_set_key);

	// Unref this action set's refcounted data
	oxr_refcounted_unref(&act_set_attached->act_set_ref->base);
}


/*
 *
 * Action set functions
 *
 */
static void
oxr_action_set_ref_destroy_cb(struct oxr_refcounted *orc)
{
	struct oxr_action_set_ref *act_set_ref = (struct oxr_action_set_ref *)orc;

	u_hashset_destroy(&act_set_ref->actions.name_store);
	u_hashset_destroy(&act_set_ref->actions.loc_store);

	free(act_set_ref);
}

static XrResult
oxr_action_set_destroy_cb(struct oxr_logger *log, struct oxr_handle_base *hb)
{
	struct oxr_action_set *act_set = (struct oxr_action_set *)hb;

	oxr_refcounted_unref(&act_set->data->base);
	act_set->data = NULL;

	if (act_set->name_item != NULL) {
		u_hashset_erase_item(act_set->inst->action_sets.name_store, act_set->name_item);
		free(act_set->name_item);
		act_set->name_item = NULL;
	}
	if (act_set->loc_item != NULL) {
		u_hashset_erase_item(act_set->inst->action_sets.loc_store, act_set->loc_item);
		free(act_set->loc_item);
		act_set->loc_item = NULL;
	}

	free(act_set);

	return XR_SUCCESS;
}

XrResult
oxr_action_set_create(struct oxr_logger *log,
                      struct oxr_instance *inst,
                      const XrActionSetCreateInfo *createInfo,
                      struct oxr_action_set **out_act_set)
{
	// Mod music for all!
	static uint32_t key_gen = 1;
	int h_ret;

	struct oxr_action_set *act_set = NULL;
	OXR_ALLOCATE_HANDLE_OR_RETURN(log, act_set, OXR_XR_DEBUG_ACTIONSET, oxr_action_set_destroy_cb, &inst->handle);

	struct oxr_action_set_ref *act_set_ref = U_TYPED_CALLOC(struct oxr_action_set_ref);
	act_set_ref->base.destroy = oxr_action_set_ref_destroy_cb;
	oxr_refcounted_ref(&act_set_ref->base);
	act_set->data = act_set_ref;

	act_set_ref->act_set_key = key_gen++;
	act_set->act_set_key = act_set_ref->act_set_key;

	act_set->inst = inst;

	h_ret = u_hashset_create(&act_set_ref->actions.name_store);
	if (h_ret != 0) {
		oxr_handle_destroy(log, &act_set->handle);
		return oxr_error(log, XR_ERROR_RUNTIME_FAILURE, "Failed to create name_store hashset");
	}

	h_ret = u_hashset_create(&act_set_ref->actions.loc_store);
	if (h_ret != 0) {
		oxr_handle_destroy(log, &act_set->handle);
		return oxr_error(log, XR_ERROR_RUNTIME_FAILURE, "Failed to create loc_store hashset");
	}

	snprintf(act_set_ref->name, sizeof(act_set_ref->name), "%s", createInfo->actionSetName);

	u_hashset_create_and_insert_str_c(inst->action_sets.name_store, createInfo->actionSetName, &act_set->name_item);
	u_hashset_create_and_insert_str_c(inst->action_sets.loc_store, createInfo->localizedActionSetName,
	                                  &act_set->loc_item);

	act_set_ref->priority = createInfo->priority;

	*out_act_set = act_set;

	return XR_SUCCESS;
}


/*
 *
 * Action functions
 *
 */

static void
oxr_action_ref_destroy_cb(struct oxr_refcounted *orc)
{
	struct oxr_action_ref *act_ref = (struct oxr_action_ref *)orc;
	free(act_ref);
}

static XrResult
oxr_action_destroy_cb(struct oxr_logger *log, struct oxr_handle_base *hb)
{
	struct oxr_action *act = (struct oxr_action *)hb;

	oxr_refcounted_unref(&act->data->base);
	act->data = NULL;

	if (act->name_item != NULL) {
		u_hashset_erase_item(act->act_set->data->actions.name_store, act->name_item);
		free(act->name_item);
		act->name_item = NULL;
	}
	if (act->loc_item != NULL) {
		u_hashset_erase_item(act->act_set->data->actions.loc_store, act->loc_item);
		free(act->loc_item);
		act->loc_item = NULL;
	}

	free(act);

	return XR_SUCCESS;
}

XrResult
oxr_action_create(struct oxr_logger *log,
                  struct oxr_action_set *act_set,
                  const XrActionCreateInfo *createInfo,
                  struct oxr_action **out_act)
{
	struct oxr_instance *inst = act_set->inst;
	struct oxr_subaction_paths subaction_paths = {0};

	// Mod music for all!
	static uint32_t key_gen = 1;

	if (!oxr_classify_sub_action_paths(log, inst, createInfo->countSubactionPaths, createInfo->subactionPaths,
	                                   &subaction_paths)) {
		return XR_ERROR_PATH_UNSUPPORTED;
	}

	struct oxr_action *act = NULL;
	OXR_ALLOCATE_HANDLE_OR_RETURN(log, act, OXR_XR_DEBUG_ACTION, oxr_action_destroy_cb, &act_set->handle);


	struct oxr_action_ref *act_ref = U_TYPED_CALLOC(struct oxr_action_ref);
	act_ref->base.destroy = oxr_action_ref_destroy_cb;
	oxr_refcounted_ref(&act_ref->base);
	act->data = act_ref;

	act_ref->act_key = key_gen++;
	act->act_key = act_ref->act_key;

	act->act_set = act_set;
	act_ref->subaction_paths = subaction_paths;
	act_ref->action_type = createInfo->actionType;

	snprintf(act_ref->name, sizeof(act_ref->name), "%s", createInfo->actionName);

	u_hashset_create_and_insert_str_c(act_set->data->actions.name_store, createInfo->actionName, &act->name_item);
	u_hashset_create_and_insert_str_c(act_set->data->actions.loc_store, createInfo->localizedActionName,
	                                  &act->loc_item);

	*out_act = act;

	return XR_SUCCESS;
}


/*
 *
 * "Exported" helper functions.
 *
 */

bool
oxr_classify_sub_action_paths(struct oxr_logger *log,
                              struct oxr_instance *inst,
                              uint32_t subaction_path_count,
                              const XrPath *subaction_paths,
                              struct oxr_subaction_paths *subaction_paths_out)
{
	const char *str = NULL;
	size_t length = 0;
	bool ret = true;

	// Reset the subaction_paths completely.
	U_ZERO(subaction_paths_out);

	if (subaction_path_count == 0) {
		subaction_paths_out->any = true;
		return ret;
	}

	for (uint32_t i = 0; i < subaction_path_count; i++) {
		XrPath path = subaction_paths[i];

#define IDENTIFY_PATH(X)                                                                                               \
	else if (path == inst->path_cache.X)                                                                           \
	{                                                                                                              \
		subaction_paths_out->X = true;                                                                         \
	}


		if (path == XR_NULL_PATH) {
			subaction_paths_out->any = true;
		}
		OXR_FOR_EACH_VALID_SUBACTION_PATH(IDENTIFY_PATH) else
		{
			oxr_path_get_string(log, inst, path, &str, &length);

			oxr_warn(log, " unrecognized sub action path '%s'", str);
			ret = false;
		}
#undef IDENTIFY_PATH
	}
	return ret;
}

XrResult
oxr_action_get_pose_input(struct oxr_session *sess,
                          uint32_t act_key,
                          const struct oxr_subaction_paths *subaction_paths_ptr,
                          struct oxr_action_input **out_input)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);

	if (act_attached == NULL) {
		return XR_SUCCESS;
	}

	struct oxr_subaction_paths subaction_paths = *subaction_paths_ptr;
	if (subaction_paths.any) {
		subaction_paths = act_attached->any_pose_subaction_path;
	}

	// Priority of inputs.
#define GET_POSE_INPUT(X)                                                                                              \
	if (act_attached->X.current.active && subaction_paths.X) {                                                     \
		*out_input = act_attached->X.inputs;                                                                   \
		return XR_SUCCESS;                                                                                     \
	}
	OXR_FOR_EACH_VALID_SUBACTION_PATH(GET_POSE_INPUT)

	// plus a fallback invocation for user
	GET_POSE_INPUT(user)
#undef GET_POSE_INPUT

	return XR_SUCCESS;
}


/*
 *
 * Not so hack functions.
 *
 */

static bool
do_inputs(struct oxr_binding *binding_point,
          struct xrt_device *xdev,
          struct xrt_binding_profile *xbp,
          XrPath matched_path,
          struct oxr_action_input inputs[OXR_MAX_BINDINGS_PER_ACTION],
          uint32_t *input_count)
{
	enum xrt_input_name name = 0;
	if (xbp == NULL) {
		name = binding_point->input;
	} else {
		for (size_t i = 0; i < xbp->input_count; i++) {
			if (binding_point->input != xbp->inputs[i].from) {
				continue;
			}

			// We have found a device mapping.
			name = xbp->inputs[i].device;
			break;
		}

		// Didn't find a mapping.
		if (name == 0) {
			return false;
		}
	}

	struct xrt_input *input = NULL;
	if (oxr_xdev_find_input(xdev, name, &input)) {
		uint32_t index = (*input_count)++;
		inputs[index].input = input;
		inputs[index].xdev = xdev;
		inputs[index].bound_path = matched_path;
		if (binding_point->dpad_activate != 0) {
			struct xrt_input *dpad_activate = NULL;
			if (!oxr_xdev_find_input(xdev, binding_point->dpad_activate, &dpad_activate)) {
				return false;
			}
			inputs[index].dpad_activate_name = binding_point->dpad_activate;
			inputs[index].dpad_activate = dpad_activate;
		}
		return true;
	}

	return false;
}

static bool
do_outputs(struct oxr_binding *binding_point,
           struct xrt_device *xdev,
           struct xrt_binding_profile *xbp,
           XrPath matched_path,
           struct oxr_action_output outputs[OXR_MAX_BINDINGS_PER_ACTION],
           uint32_t *output_count)
{
	enum xrt_output_name name = 0;
	if (xbp == NULL) {
		name = binding_point->output;
	} else {
		for (size_t i = 0; i < xbp->output_count; i++) {
			if (binding_point->output != xbp->outputs[i].from) {
				continue;
			}

			// We have found a device mapping.
			name = xbp->outputs[i].device;
			break;
		}

		// Didn't find a mapping.
		if (name == 0) {
			return false;
		}
	}

	struct xrt_output *output = NULL;
	if (oxr_xdev_find_output(xdev, name, &output)) {
		uint32_t index = (*output_count)++;
		outputs[index].name = name;
		outputs[index].xdev = xdev;
		outputs[index].bound_path = matched_path;
		return true;
	}

	return false;
}

/*!
 * Delegate to @ref do_outputs or @ref do_inputs depending on whether the action
 * is output or input.
 */
static bool
do_io_bindings(struct oxr_binding *binding_point,
               struct oxr_action *act,
               struct xrt_device *xdev,
               struct xrt_binding_profile *xbp,
               XrPath matched_path,
               struct oxr_action_input inputs[OXR_MAX_BINDINGS_PER_ACTION],
               uint32_t *input_count,
               struct oxr_action_output outputs[OXR_MAX_BINDINGS_PER_ACTION],
               uint32_t *output_count)
{
	if (act->data->action_type == XR_ACTION_TYPE_VIBRATION_OUTPUT) {
		return do_outputs( //
		    binding_point, //
		    xdev,          //
		    xbp,           //
		    matched_path,  //
		    outputs,       //
		    output_count); //
	}
	return do_inputs(  //
	    binding_point, //
	    xdev,          //
	    xbp,           //
	    matched_path,  //
	    inputs,        //
	    input_count);  //
}

static struct xrt_binding_profile *
get_matching_binding_profile(struct oxr_interaction_profile *profile, struct xrt_device *xdev)
{
	for (size_t i = 0; i < xdev->binding_profile_count; i++) {
		if (xdev->binding_profiles[i].name == profile->xname) {
			return &xdev->binding_profiles[i];
		}
	}

	return NULL;
}

static XrPath
get_matched_xrpath(struct oxr_binding *b, struct oxr_action *act)
{
	XrPath preferred_path = XR_NULL_PATH;
	for (uint32_t i = 0; i < b->key_count; i++) {
		if (b->keys[i] == act->act_key) {
			uint32_t preferred_path_index = XR_NULL_PATH;
			preferred_path_index = b->preferred_binding_path_index[i];
			preferred_path = b->paths[preferred_path_index];
			break;
		}
	}
	return preferred_path;
}

static void
get_binding(struct oxr_logger *log,
            struct oxr_sink_logger *slog,
            struct oxr_session *sess,
            struct oxr_action *act,
            struct oxr_interaction_profile *profile,
            enum oxr_subaction_path subaction_path,
            struct oxr_action_input inputs[OXR_MAX_BINDINGS_PER_ACTION],
            uint32_t *input_count,
            struct oxr_action_output outputs[OXR_MAX_BINDINGS_PER_ACTION],
            uint32_t *output_count)
{
	struct xrt_device *xdev = NULL;
	struct oxr_binding *binding_points[OXR_MAX_BINDINGS_PER_ACTION];
	const char *profile_str;
	const char *user_path_str;
	size_t length;

	//! @todo This probably falls on its head if the application doesn't use
	//! sub action paths.
	switch (subaction_path) {
#define PATH_CASE(NAME, NAMECAPS, PATH)                                                                                \
	case OXR_SUB_ACTION_PATH_##NAMECAPS:                                                                           \
		user_path_str = PATH;                                                                                  \
		xdev = GET_XDEV_BY_ROLE(sess->sys, NAME);                                                              \
		break;

		OXR_FOR_EACH_VALID_SUBACTION_PATH_DETAILED(PATH_CASE)
#undef PATH_CASE

		// Manually-coded fallback for not-really-valid /user
	case OXR_SUB_ACTION_PATH_USER:
		user_path_str = "/user";
		xdev = NULL;
		break;
	default: break;
	}

	oxr_slog(slog, "\tFor: %s\n", user_path_str);

	if (xdev == NULL) {
		oxr_slog(slog, "\t\tNo xdev!\n");
		return;
	}

	if (profile == NULL) {
		oxr_slog(slog, "\t\tNo profile!\n");
		return;
	}

	oxr_path_get_string(log, sess->sys->inst, profile->path, &profile_str, &length);

	oxr_slog(slog, "\t\tProfile: %s\n", profile_str);

	/*!
	 * Lookup device binding that matches the interactive profile, this
	 * is used as a fallback should the device not match the interactive
	 * profile. This allows the device to provide a mapping from one device
	 * to itself.
	 */
	struct xrt_binding_profile *xbp = get_matching_binding_profile(profile, xdev);

	// No point in proceeding here without either.
	if (profile->xname != xdev->name && xbp == NULL) {
		oxr_slog(slog, "\t\t\tProfile not for device and no xbp fallback!\n");
		return;
	}

	size_t num = 0;
	oxr_binding_find_bindings_from_key(log, profile, act->act_key, binding_points, &num);
	if (num == 0) {
		oxr_slog(slog, "\t\t\tNo bindings!\n");
		return;
	}

	for (size_t i = 0; i < num; i++) {
		const char *str = NULL;
		struct oxr_binding *binding_point = binding_points[i];

		XrPath matched_path = get_matched_xrpath(binding_point, act);

		oxr_path_get_string(log, sess->sys->inst, matched_path, &str, &length);
		oxr_slog(slog, "\t\t\tBinding: %s\n", str);

		if (binding_point->subaction_path != subaction_path) {
			oxr_slog(slog, "\t\t\t\tRejected! (SUB PATH)\n");
			continue;
		}

		bool found = do_io_bindings( //
		    binding_point,           //
		    act,                     //
		    xdev,                    //
		    xbp,                     //
		    matched_path,            //
		    inputs,                  //
		    input_count,             //
		    outputs,                 //
		    output_count);           //

		if (found) {
			if (xbp == NULL) {
				oxr_slog(slog, "\t\t\t\tBound (xdev)!\n");
			} else {
				oxr_slog(slog, "\t\t\t\tBound (xbp)!\n");
			}
			continue;
		}

		if (xbp == NULL) {
			oxr_slog(slog, "\t\t\t\tRejected! (NO XDEV NAME)\n");
		} else {
			oxr_slog(slog, "\t\t\t\tRejected! (NO XBINDING)\n");
		}
	}
}


struct oxr_profiles_per_subaction
{
#define PROFILE_MEMBER(X) struct oxr_interaction_profile *X;
	OXR_FOR_EACH_VALID_SUBACTION_PATH(PROFILE_MEMBER)
#undef PROFILE_MEMBER
};

/*!
 * @public @memberof oxr_action_attachment
 */
static XrResult
oxr_action_attachment_bind(struct oxr_logger *log,
                           struct oxr_action_attachment *act_attached,
                           struct oxr_action *act,
                           const struct oxr_profiles_per_subaction *profiles)
{
	struct oxr_sink_logger slog = {0};
	struct oxr_action_ref *act_ref = act->data;
	struct oxr_session *sess = act_attached->sess;

	// Start logging into a single buffer.
	oxr_slog(&slog, ": Binding %s/%s\n", act->act_set->data->name, act_ref->name);

	if (act_ref->subaction_paths.user || act_ref->subaction_paths.any) {
#if 0
		oxr_action_bind_io(log, &slog, sess, act, &act_attached->user,
		                   user, OXR_SUB_ACTION_PATH_USER);
#endif
	}

#define BIND_SUBACTION(NAME, NAME_CAPS, PATH)                                                                          \
	if (act_ref->subaction_paths.NAME || act_ref->subaction_paths.any) {                                           \
		oxr_action_bind_io(log, &slog, sess, act, &act_attached->NAME, profiles->NAME,                         \
		                   OXR_SUB_ACTION_PATH_##NAME_CAPS);                                                   \
	}
	OXR_FOR_EACH_VALID_SUBACTION_PATH_DETAILED(BIND_SUBACTION)
#undef BIND_SUBACTION


	/*!
	 * The any sub path is special cased for poses, it binds to one sub path
	 * and sticks with it.
	 */
	if (act_ref->action_type == XR_ACTION_TYPE_POSE_INPUT) {

#define POSE_ANY(NAME)                                                                                                 \
	if ((act_ref->subaction_paths.NAME || act_ref->subaction_paths.any) && act_attached->NAME.input_count > 0) {   \
		act_attached->any_pose_subaction_path.NAME = true;                                                     \
		oxr_slog(&slog, "\tFor: <any>\n\t\tBinding any pose to " #NAME ".\n");                                 \
	} else
		OXR_FOR_EACH_VALID_SUBACTION_PATH(POSE_ANY)
#undef POSE_ANY

		{
			oxr_slog(&slog,
			         "\tFor: <any>\n\t\tNo active sub paths for "
			         "the any pose!\n");
		}
	}

	oxr_slog(&slog, "\tDone");

	// Also frees all data.
	if (sess->sys->inst->debug_bindings) {
		oxr_log_slog(log, &slog);
	} else {
		oxr_slog_cancel(&slog);
	}

	return XR_SUCCESS;
}

static void
oxr_action_cache_stop_output(struct oxr_logger *log, struct oxr_session *sess, struct oxr_action_cache *cache)
{
	// Set this as stopped.
	cache->stop_output_time = 0;

	union xrt_output_value value = {0};

	for (uint32_t i = 0; i < cache->output_count; i++) {
		struct oxr_action_output *output = &cache->outputs[i];
		struct xrt_device *xdev = output->xdev;

		xrt_device_set_output(xdev, output->name, &value);
	}
}

static bool
oxr_input_is_input_for_cache(struct oxr_action_input *action_input, struct oxr_action_cache *cache)
{
	for (size_t i = 0; i < cache->input_count; i++) {
		if (action_input->bound_path == cache->inputs[i].bound_path) {
			return true;
		}
	}
	return false;
}

static bool
oxr_input_is_bound_in_act_set(struct oxr_action_input *action_input, struct oxr_action_set_attachment *act_set_attached)
{
	for (size_t i = 0; i < act_set_attached->action_attachment_count; i++) {
		struct oxr_action_attachment *act_attached = &act_set_attached->act_attachments[i];

#define ACCUMULATE_PATHS(X)                                                                                            \
	if (oxr_input_is_input_for_cache(action_input, &act_attached->X)) {                                            \
		return true;                                                                                           \
	}
		OXR_FOR_EACH_SUBACTION_PATH(ACCUMULATE_PATHS)
#undef ACCUMULATE_PATHS
	}
	return false;
}

static bool
oxr_input_supressed(struct oxr_session *sess,
                    uint32_t countActionSets,
                    const XrActiveActionSet *actionSets,
                    struct oxr_subaction_paths *subaction_path,
                    struct oxr_action_attachment *act_attached,
                    struct oxr_action_input *action_input)
{
	struct oxr_action_set_ref *act_set_ref = act_attached->act_set_attached->act_set_ref;
	uint32_t priority = act_set_ref->priority;

	// find sources that are bound to an action in a set with higher prio
	for (uint32_t i = 0; i < countActionSets; i++) {
		XrActionSet set = actionSets[i].actionSet;

		struct oxr_action_set *other_act_set = NULL;
		struct oxr_action_set_attachment *other_act_set_attached = NULL;
		oxr_session_get_action_set_attachment(sess, set, &other_act_set_attached, &other_act_set);

		if (other_act_set_attached == NULL) {
			continue;
		}

		/* skip the action set that the current action is in */
		if (other_act_set_attached->act_set_ref == act_set_ref) {
			continue;
		}

		/* input may be suppressed by action set with higher prio */
		if (other_act_set_attached->act_set_ref->priority <= priority) {
			continue;
		}

		/* Currently updated input source with subactionpath X can be
		 * suppressed, if input source also occurs in action set with
		 * higher priority if
		 * - high prio set syncs w/ ANY subactionpath or
		 * - high prio set syncs w/ subactionpath matching this input
		 *   subactionpath
		 */
		bool relevant_subactionpath = other_act_set_attached->requested_subaction_paths.any;

#define ACCUMULATE_PATHS(X)                                                                                            \
	relevant_subactionpath |= (other_act_set_attached->requested_subaction_paths.X && subaction_path->X);
		OXR_FOR_EACH_SUBACTION_PATH(ACCUMULATE_PATHS)
#undef ACCUMULATE_PATHS

		if (!relevant_subactionpath) {
			continue;
		}

		if (oxr_input_is_bound_in_act_set(action_input, other_act_set_attached)) {
			return true;
		}
	}

	return false;
}

static bool
oxr_input_combine_input(struct oxr_session *sess,
                        uint32_t countActionSets,
                        const XrActiveActionSet *actionSets,
                        struct oxr_action_attachment *act_attached,
                        struct oxr_subaction_paths *subaction_path,
                        struct oxr_action_cache *cache,
                        struct oxr_input_value_tagged *out_input,
                        int64_t *timestamp,
                        bool *is_active)
{
	struct oxr_action_input *inputs = cache->inputs;
	size_t input_count = cache->input_count;

	if (input_count == 0) {
		*is_active = false;
		return true;
	}

	bool any_active = false;
	struct oxr_input_value_tagged res = {0};
	int64_t res_timestamp = inputs[0].input->timestamp;

	for (size_t i = 0; i < input_count; i++) {
		struct oxr_action_input *action_input = &(inputs[i]);
		struct xrt_input *input = action_input->input;

		// suppress input if it is also bound to action in set with
		// higher priority
		if (oxr_input_supressed(sess, countActionSets, actionSets, subaction_path, act_attached,
		                        action_input)) {
			continue;
		}

		if (input->active) {
			any_active = true;
		} else {
			continue;
		}

		struct oxr_input_value_tagged raw_input = {
		    .type = XRT_GET_INPUT_TYPE(input->name),
		    .value = input->value,
		};

		struct oxr_input_value_tagged transformed = {0};
		if (!oxr_input_transform_process(action_input->transforms, action_input->transform_count, &raw_input,
		                                 &transformed)) {
			// We couldn't transform, how strange. Reset all state.
			// At this level we don't know what action this is, etc.
			// so a warning message isn't very helpful.
			return false;
		}

		// at this stage type should be "compatible" to action
		res.type = transformed.type;

		switch (transformed.type) {
		case XRT_INPUT_TYPE_BOOLEAN:
			res.value.boolean |= transformed.value.boolean;

			/* Special case bool: all bool inputs are combined with
			 * OR. The action only changes to true on the earliest
			 * input that sets it to true, and to false on the
			 * latest input that is false. */
			if (res.value.boolean && transformed.value.boolean && input->timestamp < res_timestamp) {
				res_timestamp = input->timestamp;
			} else if (!res.value.boolean && !transformed.value.boolean &&
			           input->timestamp > res_timestamp) {
				res_timestamp = input->timestamp;
			}
			break;
		case XRT_INPUT_TYPE_VEC1_MINUS_ONE_TO_ONE:
		case XRT_INPUT_TYPE_VEC1_ZERO_TO_ONE:
			if (fabsf(transformed.value.vec1.x) > fabsf(res.value.vec1.x)) {
				res.value.vec1.x = transformed.value.vec1.x;
				res_timestamp = input->timestamp;
			}
			break;
		case XRT_INPUT_TYPE_VEC2_MINUS_ONE_TO_ONE: {
			float res_sq = res.value.vec2.x * res.value.vec2.x + res.value.vec2.y * res.value.vec2.y;
			float trans_sq = transformed.value.vec2.x * transformed.value.vec2.x +
			                 transformed.value.vec2.y * transformed.value.vec2.y;
			if (trans_sq > res_sq) {
				res.value.vec2 = transformed.value.vec2;
				res_timestamp = input->timestamp;
			}
		} break;
		case XRT_INPUT_TYPE_VEC3_MINUS_ONE_TO_ONE:
			// OpenXR has no vec3 right now.
			break;
		case XRT_INPUT_TYPE_POSE:
			// shouldn't be possible to get here
			break;
		case XRT_INPUT_TYPE_HAND_TRACKING:
			// shouldn't be possible to get here
			break;
		}
	}

	*is_active = any_active;
	*out_input = res;
	*timestamp = res_timestamp;

	return true;
}

/*!
 * Called during xrSyncActions.
 *
 * @private @memberof oxr_action_cache
 */
static void
oxr_action_cache_update(struct oxr_logger *log,
                        struct oxr_session *sess,
                        uint32_t countActionSets,
                        const XrActiveActionSet *actionSets,
                        struct oxr_action_attachment *act_attached,
                        struct oxr_action_cache *cache,
                        int64_t time,
                        struct oxr_subaction_paths *subaction_path,
                        bool selected)
{
	struct oxr_action_state last = cache->current;

	if (!selected) {
		if (cache->stop_output_time > 0) {
			oxr_action_cache_stop_output(log, sess, cache);
		}
		U_ZERO(&cache->current);
		return;
	}

	struct oxr_input_value_tagged combined;
	int64_t timestamp;
	bool is_active;

	/* a cache can only have outputs or inputs, not both */
	if (cache->output_count > 0) {
		cache->current.active = true;
		if (cache->stop_output_time < time) {
			oxr_action_cache_stop_output(log, sess, cache);
		}
	} else if (cache->input_count > 0) {

		if (!oxr_input_combine_input(sess, countActionSets, actionSets, act_attached, subaction_path, cache,
		                             &combined, &timestamp, &is_active)) {
			oxr_log(log, "Failed to get/combine input values '%s'", act_attached->act_ref->name);
			return;
		}

		// If the input is not active signal that.
		if (!is_active) {
			// Reset all state.
			U_ZERO(&cache->current);
			return;
		}

		// Signal that the input is active, always set just to be sure.
		cache->current.active = true;

		bool changed = false;
		switch (combined.type) {
		case XRT_INPUT_TYPE_VEC1_ZERO_TO_ONE:
		case XRT_INPUT_TYPE_VEC1_MINUS_ONE_TO_ONE: {
			changed = (combined.value.vec1.x != last.value.vec1.x);
			cache->current.value.vec1.x = combined.value.vec1.x;
			break;
		}
		case XRT_INPUT_TYPE_VEC2_MINUS_ONE_TO_ONE: {
			changed = (combined.value.vec2.x != last.value.vec2.x) ||
			          (combined.value.vec2.y != last.value.vec2.y);
			cache->current.value.vec2.x = combined.value.vec2.x;
			cache->current.value.vec2.y = combined.value.vec2.y;
			break;
		}
#if 0
		// Untested, we have no VEC3 input.
		case XRT_INPUT_TYPE_VEC3_MINUS_ONE_TO_ONE: {
			changed = (combined.value.vec3.x != last.vec3.x) ||
			          (combined.value.vec3.y != last.vec3.y) ||
			          (combined.value.vec3.z != last.vec3.z);
			cache->current.vec3.x = combined.value.vec3.x;
			cache->current.vec3.y = combined.value.vec3.y;
			cache->current.vec3.z = combined.value.vec3.z;
			break;
		}
#endif
		case XRT_INPUT_TYPE_BOOLEAN: {
			changed = (combined.value.boolean != last.value.boolean);
			cache->current.value.boolean = combined.value.boolean;
			break;
		}
		case XRT_INPUT_TYPE_POSE: return;
		default:
			// Should not end up here.
			assert(false);
		}

		if (last.active && changed) {
			// We were active last sync, and we've changed since
			// then
			cache->current.timestamp = timestamp;
			cache->current.changed = true;
		} else if (last.active) {
			// We were active last sync, but we haven't changed
			// since then.
			cache->current.timestamp = last.timestamp;
			cache->current.changed = false;
		} else {
			// We are active now but weren't active last time.
			cache->current.timestamp = timestamp;
			cache->current.changed = false;
		}
	}
}

#define BOOL_CHECK(NAME)                                                                                               \
	if (act_attached->NAME.current.active) {                                                                       \
		active |= true;                                                                                        \
		value |= act_attached->NAME.current.value.boolean;                                                     \
		timestamp = act_attached->NAME.current.timestamp;                                                      \
	}
#define VEC1_CHECK(NAME)                                                                                               \
	if (act_attached->NAME.current.active) {                                                                       \
		active |= true;                                                                                        \
		if (value < act_attached->NAME.current.value.vec1.x) {                                                 \
			value = act_attached->NAME.current.value.vec1.x;                                               \
			timestamp = act_attached->NAME.current.timestamp;                                              \
		}                                                                                                      \
	}
#define VEC2_CHECK(NAME)                                                                                               \
	if (act_attached->NAME.current.active) {                                                                       \
		active |= true;                                                                                        \
		float curr_x = act_attached->NAME.current.value.vec2.x;                                                \
		float curr_y = act_attached->NAME.current.value.vec2.y;                                                \
		float curr_d = curr_x * curr_x + curr_y * curr_y;                                                      \
		if (distance < curr_d) {                                                                               \
			x = curr_x;                                                                                    \
			y = curr_y;                                                                                    \
			distance = curr_d;                                                                             \
			timestamp = act_attached->NAME.current.timestamp;                                              \
		}                                                                                                      \
	}

/*!
 * Called during each xrSyncActions.
 *
 * @private @memberof oxr_action_attachment
 */
static void
oxr_action_attachment_update(struct oxr_logger *log,
                             struct oxr_session *sess,
                             uint32_t countActionSets,
                             const XrActiveActionSet *actionSets,
                             struct oxr_action_attachment *act_attached,
                             int64_t time,
                             struct oxr_subaction_paths subaction_paths)
{
	// This really shouldn't be happening.
	if (act_attached == NULL) {
		return;
	}

	//! @todo "/user" sub-action path.

#define UPDATE_SELECT(X)                                                                                               \
	struct oxr_subaction_paths subaction_paths_##X = {0};                                                          \
	subaction_paths_##X.X = true;                                                                                  \
	bool select_##X = subaction_paths.X || subaction_paths.any;                                                    \
	oxr_action_cache_update(log, sess, countActionSets, actionSets, act_attached, &act_attached->X, time,          \
	                        &subaction_paths_##X, select_##X);

	OXR_FOR_EACH_VALID_SUBACTION_PATH(UPDATE_SELECT)
#undef UPDATE_SELECT

	/*
	 * Any state.
	 */
	struct oxr_action_state last = act_attached->any_state;
	bool active = false;
	bool changed = false;
	XrTime timestamp = 0;

	switch (act_attached->act_ref->action_type) {
	case XR_ACTION_TYPE_BOOLEAN_INPUT: {
		bool value = false;
		OXR_FOR_EACH_VALID_SUBACTION_PATH(BOOL_CHECK)

		changed = (last.value.boolean != value);
		act_attached->any_state.value.boolean = value;
		break;
	}
	case XR_ACTION_TYPE_FLOAT_INPUT: {
		// Smaller than any possible real value
		float value = -2.0f; // NOLINT
		OXR_FOR_EACH_VALID_SUBACTION_PATH(VEC1_CHECK)

		changed = last.value.vec1.x != value;
		act_attached->any_state.value.vec1.x = value;
		break;
	}
	case XR_ACTION_TYPE_VECTOR2F_INPUT: {
		float x = 0.0f;
		float y = 0.0f;
		float distance = -1.0f;
		OXR_FOR_EACH_VALID_SUBACTION_PATH(VEC2_CHECK)

		changed = (last.value.vec2.x != x) || (last.value.vec2.y != y);
		act_attached->any_state.value.vec2.x = x;
		act_attached->any_state.value.vec2.y = y;
		break;
	}
	default:
	case XR_ACTION_TYPE_POSE_INPUT:
	case XR_ACTION_TYPE_VIBRATION_OUTPUT:
		// Nothing to do
		//! @todo You sure?
		return;
	}

	if (!active) {
		U_ZERO(&act_attached->any_state);
	} else if (last.active && changed) {
		act_attached->any_state.timestamp = timestamp;
		act_attached->any_state.changed = true;
		act_attached->any_state.active = true;
	} else if (last.active) {
		act_attached->any_state.timestamp = last.timestamp;
		act_attached->any_state.changed = false;
		act_attached->any_state.active = true;
	} else {
		act_attached->any_state.timestamp = timestamp;
		act_attached->any_state.changed = false;
		act_attached->any_state.active = true;
	}
}
/*!
 * Try to produce a transform chain to convert the available input into the
 * desired input type.
 *
 * Populates @p action_input->transforms and @p action_input->transform_count on
 * success.
 *
 * @returns false if it could not, true if it could
 */
static bool
oxr_action_populate_input_transform(struct oxr_logger *log,
                                    struct oxr_sink_logger *slog,
                                    struct oxr_session *sess,
                                    struct oxr_action *act,
                                    struct oxr_action_input *action_input)
{
	assert(action_input->transforms == NULL);
	assert(action_input->transform_count == 0);
	const char *str;
	size_t length;
	oxr_path_get_string(log, sess->sys->inst, action_input->bound_path, &str, &length);

	enum xrt_input_type t = XRT_GET_INPUT_TYPE(action_input->input->name);

	return oxr_input_transform_create_chain(log, slog, t, act->data->action_type, act->data->name, str,
	                                        &action_input->transforms, &action_input->transform_count);
}
/*!
 * Find dpad settings in @p dpad_entry whose binding path
 * is a prefix of @p bound_path_string.
 *
 * @returns true if settings were found and written to @p out_dpad_settings
 */
static bool
find_matching_dpad(struct oxr_logger *log,
                   struct oxr_instance *inst,
                   struct oxr_dpad_entry *dpad_entry,
                   const char *bound_path_string,
                   struct oxr_dpad_binding_modification **out_dpad_binding)
{
	if (dpad_entry != NULL) {
		for (uint32_t i = 0; i < dpad_entry->dpad_count; i++) {
			const char *dpad_path_string;
			size_t dpad_path_length;
			oxr_path_get_string(log, inst, dpad_entry->dpads[i].binding, &dpad_path_string,
			                    &dpad_path_length);
			if (strncmp(bound_path_string, dpad_path_string, dpad_path_length) == 0) {
				*out_dpad_binding = &dpad_entry->dpads[i];
				return true;
			}
		}
	}
	return false;
}

/*!
 * Try to produce a transform chain to create a dpad button from the selected input
 * (potentially using other inputs like `/force` in the process)
 *
 * Populates @p action_input->transforms and @p action_input->transform_count on
 * success.
 *
 * @returns false if it could not, true if it could
 */
static bool
oxr_action_populate_input_transform_dpad(struct oxr_logger *log,
                                         struct oxr_sink_logger *slog,
                                         struct oxr_session *sess,
                                         struct oxr_action *act,
                                         struct oxr_dpad_entry *dpad_entry,
                                         enum oxr_dpad_region dpad_region,
                                         struct oxr_interaction_profile *profile,
                                         struct oxr_action_input *action_inputs,
                                         uint32_t action_input_count,
                                         uint32_t selected_input)
{
	struct oxr_action_input *action_input = &(action_inputs[selected_input]);
	assert(action_input->transforms == NULL);
	assert(action_input->transform_count == 0);

	const char *bound_path_string;
	size_t bound_path_length;
	oxr_path_get_string(log, sess->sys->inst, action_input->bound_path, &bound_path_string, &bound_path_length);

	// find correct dpad entry
	struct oxr_dpad_binding_modification *dpad_binding_modification = NULL;
	find_matching_dpad(log, sess->sys->inst, dpad_entry, bound_path_string, &dpad_binding_modification);

	enum xrt_input_type t = XRT_GET_INPUT_TYPE(action_input->input->name);
	enum xrt_input_type activate_t = XRT_GET_INPUT_TYPE(action_input->dpad_activate_name);

	return oxr_input_transform_create_chain_dpad(
	    log, slog, t, act->data->action_type, bound_path_string, dpad_binding_modification, dpad_region, activate_t,
	    action_input->dpad_activate, &action_input->transforms, &action_input->transform_count);
}

// based on get_subaction_path_from_path
static bool
get_dpad_region_from_path(struct oxr_logger *log,
                          struct oxr_instance *inst,
                          XrPath path,
                          enum oxr_dpad_region *out_dpad_region)
{
	const char *str = NULL;
	size_t length = 0;
	XrResult ret;

	ret = oxr_path_get_string(log, inst, path, &str, &length);
	if (ret != XR_SUCCESS) {
		return false;
	}

	// TODO: surely there's a better way to do this?
	if (length >= 10 && strncmp("/dpad_left", str + (length - 10), 10) == 0) {
		*out_dpad_region = OXR_DPAD_REGION_LEFT;
		return true;
	}
	if (length >= 11 && strncmp("/dpad_right", str + (length - 11), 11) == 0) {
		*out_dpad_region = OXR_DPAD_REGION_RIGHT;
		return true;
	}
	if (length >= 8 && strncmp("/dpad_up", str + (length - 8), 8) == 0) {
		*out_dpad_region = OXR_DPAD_REGION_UP;
		return true;
	}
	if (length >= 10 && strncmp("/dpad_down", str + (length - 10), 10) == 0) {
		*out_dpad_region = OXR_DPAD_REGION_DOWN;
		return true;
	}
	if (length >= 12 && strncmp("/dpad_center", str + (length - 12), 12) == 0) {
		*out_dpad_region = OXR_DPAD_REGION_CENTER;
		return true;
	}

	return false;
}

static void
oxr_action_bind_io(struct oxr_logger *log,
                   struct oxr_sink_logger *slog,
                   struct oxr_session *sess,
                   struct oxr_action *act,
                   struct oxr_action_cache *cache,
                   struct oxr_interaction_profile *profile,
                   enum oxr_subaction_path subaction_path)
{
	struct oxr_action_input inputs[OXR_MAX_BINDINGS_PER_ACTION] = {0};
	uint32_t input_count = 0;
	struct oxr_action_output outputs[OXR_MAX_BINDINGS_PER_ACTION] = {0};
	uint32_t output_count = 0;

	get_binding(log, slog, sess, act, profile, subaction_path, inputs, &input_count, outputs, &output_count);

	cache->current.active = false;

	if (input_count > 0) {
		uint32_t count = 0;
		cache->current.active = true;
		cache->inputs = U_TYPED_ARRAY_CALLOC(struct oxr_action_input, input_count);
		for (uint32_t i = 0; i < input_count; i++) {
			// Only add the input if we can find a transform.

			enum oxr_dpad_region dpad_region;
			if (get_dpad_region_from_path(log, sess->sys->inst, inputs[i].bound_path, &dpad_region)) {
				struct oxr_dpad_entry *entry =
				    oxr_dpad_state_get(&profile->dpad_state, act->act_set->act_set_key);
				if (oxr_action_populate_input_transform_dpad(log, slog, sess, act, entry, dpad_region,
				                                             profile, inputs, input_count, i)) {
					cache->inputs[count++] = inputs[i];
					continue;
				}
			} else if (oxr_action_populate_input_transform(log, slog, sess, act, &(inputs[i]))) {
				cache->inputs[count++] = inputs[i];
				continue;
			}

			oxr_slog(slog, "\t\t\t\tRejected! (NO TRANSFORM)\n");
		}

		// No inputs found, prented we never bound it.
		if (count == 0) {
			free(cache->inputs);
			cache->inputs = NULL;
		}

		cache->input_count = count;
	}

	if (output_count > 0) {
		cache->current.active = true;
		cache->outputs = U_TYPED_ARRAY_CALLOC(struct oxr_action_output, output_count);
		for (uint32_t i = 0; i < output_count; i++) {
			cache->outputs[i] = outputs[i];
		}
		cache->output_count = output_count;
	}
}


/*
 *
 * Session functions.
 *
 */

/*!
 * Given an Action Set handle, return the @ref oxr_action_set and the associated
 * @ref oxr_action_set_attachment in the given Session.
 *
 * @private @memberof oxr_session
 */
static void
oxr_session_get_action_set_attachment(struct oxr_session *sess,
                                      XrActionSet actionSet,
                                      struct oxr_action_set_attachment **act_set_attached,
                                      struct oxr_action_set **act_set)
{
	void *ptr = NULL;
	*act_set = XRT_CAST_OXR_HANDLE_TO_PTR(struct oxr_action_set *, actionSet);
	*act_set_attached = NULL;

	// In case no action_sets have been attached.
	if (sess->act_sets_attachments_by_key == NULL) {
		return;
	}

	int ret = u_hashmap_int_find(sess->act_sets_attachments_by_key, (*act_set)->act_set_key, &ptr);
	if (ret == 0) {
		*act_set_attached = (struct oxr_action_set_attachment *)ptr;
	}
}

/*!
 * Given an action act_key, look up the @ref oxr_action_attachment of the
 * associated action in the given Session.
 *
 * @private @memberof oxr_session
 */
static void
oxr_session_get_action_attachment(struct oxr_session *sess,
                                  uint32_t act_key,
                                  struct oxr_action_attachment **out_act_attached)
{
	void *ptr = NULL;

	int ret = u_hashmap_int_find(sess->act_attachments_by_key, act_key, &ptr);
	if (ret == 0) {
		*out_act_attached = (struct oxr_action_attachment *)ptr;
	}
}

static inline size_t
oxr_handle_base_get_num_children(struct oxr_handle_base *hb)
{
	size_t ret = 0;
	for (uint32_t i = 0; i < XRT_MAX_HANDLE_CHILDREN; ++i) {
		if (hb->children[i] != NULL) {
			++ret;
		}
	}
	return ret;
}

XrResult
oxr_session_attach_action_sets(struct oxr_logger *log,
                               struct oxr_session *sess,
                               const XrSessionActionSetsAttachInfo *bindInfo)
{
	struct oxr_instance *inst = sess->sys->inst;
	struct oxr_profiles_per_subaction profiles = {0};
#define FIND_PROFILE(X) oxr_find_profile_for_device(log, inst, GET_XDEV_BY_ROLE(sess->sys, X), &profiles.X);
	OXR_FOR_EACH_VALID_SUBACTION_PATH(FIND_PROFILE)
#undef FIND_PROFILE

	// Allocate room for list. No need to check if anything has been
	// attached the API function does that.
	sess->action_set_attachment_count = bindInfo->countActionSets;
	sess->act_set_attachments =
	    U_TYPED_ARRAY_CALLOC(struct oxr_action_set_attachment, sess->action_set_attachment_count);

	// Set up the per-session data for these action sets.
	for (uint32_t i = 0; i < sess->action_set_attachment_count; i++) {
		struct oxr_action_set *act_set =
		    XRT_CAST_OXR_HANDLE_TO_PTR(struct oxr_action_set *, bindInfo->actionSets[i]);
		struct oxr_action_set_ref *act_set_ref = act_set->data;
		act_set_ref->ever_attached = true;
		struct oxr_action_set_attachment *act_set_attached = &sess->act_set_attachments[i];
		oxr_action_set_attachment_init(log, sess, act_set, act_set_attached);

		// Allocate the action attachments for this set.
		act_set_attached->action_attachment_count = oxr_handle_base_get_num_children(&act_set->handle);
		act_set_attached->act_attachments =
		    U_TYPED_ARRAY_CALLOC(struct oxr_action_attachment, act_set_attached->action_attachment_count);

		// Set up the per-session data for the actions.
		uint32_t child_index = 0;
		for (uint32_t k = 0; k < XRT_MAX_HANDLE_CHILDREN; k++) {
			struct oxr_action *act = (struct oxr_action *)act_set->handle.children[k];
			if (act == NULL) {
				continue;
			}

			struct oxr_action_attachment *act_attached = &act_set_attached->act_attachments[child_index];
			oxr_action_attachment_init(log, act_set_attached, act_attached, act);
			oxr_action_attachment_bind(log, act_attached, act, &profiles);
			++child_index;
		}
	}

#define POPULATE_PROFILE(X)                                                                                            \
	if (profiles.X != NULL) {                                                                                      \
		sess->X = profiles.X->path;                                                                            \
		oxr_event_push_XrEventDataInteractionProfileChanged(log, sess);                                        \
	}
	OXR_FOR_EACH_VALID_SUBACTION_PATH(POPULATE_PROFILE)
#undef POPULATE_PROFILE
	return oxr_session_success_result(sess);
}

XrResult
oxr_action_sync_data(struct oxr_logger *log,
                     struct oxr_session *sess,
                     uint32_t countActionSets,
                     const XrActiveActionSet *actionSets)
{
	struct oxr_action_set *act_set = NULL;
	struct oxr_action_set_attachment *act_set_attached = NULL;

	// Check that all action sets has been attached.
	for (uint32_t i = 0; i < countActionSets; i++) {
		oxr_session_get_action_set_attachment(sess, actionSets[i].actionSet, &act_set_attached, &act_set);
		if (act_set_attached == NULL) {
			return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED,
			                 "(actionSets[%i].actionSet) action set '%s' has "
			                 "not been attached to this session",
			                 i, act_set != NULL ? act_set->data->name : "NULL");
		}
	}

	// Synchronize outputs to this time.
	int64_t now = time_state_get_now(sess->sys->inst->timekeeping);

	// Loop over all xdev devices.
	for (size_t i = 0; i < sess->sys->xsysd->xdev_count; i++) {
		oxr_xdev_update(sess->sys->xsysd->xdevs[i]);
	}

	// Reset all action set attachments.
	for (size_t i = 0; i < sess->action_set_attachment_count; ++i) {
		act_set_attached = &sess->act_set_attachments[i];
		U_ZERO(&act_set_attached->requested_subaction_paths);
	}

	// Go over all requested action sets and update their attachment.
	//! @todo can be listed more than once with different paths!
	for (uint32_t i = 0; i < countActionSets; i++) {
		struct oxr_subaction_paths subaction_paths;
		oxr_session_get_action_set_attachment(sess, actionSets[i].actionSet, &act_set_attached, &act_set);
		assert(act_set_attached != NULL);

		if (!oxr_classify_sub_action_paths(log, sess->sys->inst, 1, &actionSets[i].subactionPath,
		                                   &subaction_paths)) {
			return XR_ERROR_PATH_UNSUPPORTED;
		}

		act_set_attached->requested_subaction_paths.any |= subaction_paths.any;

		/* never error when requesting any subactionpath */
		bool any_action_with_subactionpath = subaction_paths.any;

#define ACCUMULATE_REQUESTED(X) act_set_attached->requested_subaction_paths.X |= subaction_paths.X;

		OXR_FOR_EACH_SUBACTION_PATH(ACCUMULATE_REQUESTED)
#undef ACCUMULATE_REQUESTED

		/* check if we have at least one action for requested subactionpath */
		for (uint32_t k = 0; k < act_set_attached->action_attachment_count; k++) {
			struct oxr_action_attachment *act_attached = &act_set_attached->act_attachments[k];

			if (act_attached == NULL) {
				continue;
			}

#define ACCUMULATE_REQUESTED(X)                                                                                        \
	any_action_with_subactionpath |= subaction_paths.X && act_attached->act_ref->subaction_paths.X;
			OXR_FOR_EACH_SUBACTION_PATH(ACCUMULATE_REQUESTED)
#undef ACCUMULATE_REQUESTED
		}
		if (!any_action_with_subactionpath) {
			return oxr_error(log, XR_ERROR_PATH_UNSUPPORTED,
			                 "No action with specified subactionpath in actionset");
		}
	}

	// Now, update all action attachments
	for (size_t i = 0; i < sess->action_set_attachment_count; ++i) {
		act_set_attached = &sess->act_set_attachments[i];
		struct oxr_subaction_paths subaction_paths = act_set_attached->requested_subaction_paths;


		for (uint32_t k = 0; k < act_set_attached->action_attachment_count; k++) {
			struct oxr_action_attachment *act_attached = &act_set_attached->act_attachments[k];

			if (act_attached == NULL) {
				continue;
			}

			oxr_action_attachment_update(log, sess, countActionSets, actionSets, act_attached, now,
			                             subaction_paths);
		}
	}

	return oxr_session_success_focused_result(sess);
}

static void
add_path_to_set(XrPath path_set[OXR_MAX_BINDINGS_PER_ACTION], XrPath new_path, uint32_t *inout_path_count)
{
	const uint32_t n = *inout_path_count;

	// Shouldn't be full
	assert(n < OXR_MAX_BINDINGS_PER_ACTION);

	for (uint32_t i = 0; i < n; ++i) {
		if (new_path == path_set[i]) {
			return;
		}
		// Should have no gaps
		assert(path_set[i] != 0);
	}
	path_set[n] = new_path;
	(*inout_path_count)++;
}

XrResult
oxr_action_enumerate_bound_sources(struct oxr_logger *log,
                                   struct oxr_session *sess,
                                   uint32_t act_key,
                                   uint32_t sourceCapacityInput,
                                   uint32_t *sourceCountOutput,
                                   XrPath *sources)
{
	struct oxr_action_attachment *act_attached = NULL;
	uint32_t path_count = 0;
	XrPath temp[OXR_MAX_BINDINGS_PER_ACTION] = {0};

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_RUNTIME_FAILURE, "act_key did not find any action");
	}

#define ACCUMULATE_PATHS(X)                                                                                            \
	if (act_attached->X.input_count > 0) {                                                                         \
		for (uint32_t i = 0; i < act_attached->X.input_count; i++) {                                           \
			add_path_to_set(temp, act_attached->X.inputs[i].bound_path, &path_count);                      \
		}                                                                                                      \
	}                                                                                                              \
	if (act_attached->X.output_count > 0) {                                                                        \
		for (uint32_t i = 0; i < act_attached->X.output_count; i++) {                                          \
			add_path_to_set(temp, act_attached->X.outputs[i].bound_path, &path_count);                     \
		}                                                                                                      \
	}

	OXR_FOR_EACH_SUBACTION_PATH(ACCUMULATE_PATHS)
#undef ACCUMULATE_PATHS

	OXR_TWO_CALL_HELPER(log, sourceCapacityInput, sourceCountOutput, sources, path_count, temp,
	                    oxr_session_success_result(sess));
}


/*
 *
 * Action get functions.
 *
 */

#define OXR_ACTION_GET_XR_STATE_FROM_ACTION_STATE_COMMON(ACTION_STATE, DATA)                                           \
	do {                                                                                                           \
		DATA->lastChangeTime = time_state_monotonic_to_ts_ns(inst->timekeeping, ACTION_STATE->timestamp);      \
		DATA->changedSinceLastSync = ACTION_STATE->changed;                                                    \
		DATA->isActive = XR_TRUE;                                                                              \
	} while (0)

static void
get_xr_state_from_action_state_bool(struct oxr_instance *inst,
                                    struct oxr_action_state *state,
                                    XrActionStateBoolean *data)
{
	/* only get here if the action is active! */
	assert(state->active);
	OXR_ACTION_GET_XR_STATE_FROM_ACTION_STATE_COMMON(state, data);
	data->currentState = state->value.boolean;
}

static void
get_xr_state_from_action_state_vec1(struct oxr_instance *inst, struct oxr_action_state *state, XrActionStateFloat *data)
{
	/* only get here if the action is active! */
	assert(state->active);
	OXR_ACTION_GET_XR_STATE_FROM_ACTION_STATE_COMMON(state, data);
	data->currentState = state->value.vec1.x;
}

static void
get_xr_state_from_action_state_vec2(struct oxr_instance *inst,
                                    struct oxr_action_state *state,
                                    XrActionStateVector2f *data)
{
	/* only get here if the action is active! */
	assert(state->active);
	OXR_ACTION_GET_XR_STATE_FROM_ACTION_STATE_COMMON(state, data);
	data->currentState.x = state->value.vec2.x;
	data->currentState.y = state->value.vec2.y;
}

/*!
 * This populates the internals of action get state functions.
 *
 * @note Keep this synchronized with OXR_FOR_EACH_SUBACTION_PATH!
 */
#define OXR_ACTION_GET_FILLER(TYPE)                                                                                    \
	if (subaction_paths.any && act_attached->any_state.active) {                                                   \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->any_state, data);                \
	}                                                                                                              \
	if (subaction_paths.user && act_attached->user.current.active) {                                               \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->user.current, data);             \
	}                                                                                                              \
	if (subaction_paths.head && act_attached->head.current.active) {                                               \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->head.current, data);             \
	}                                                                                                              \
	if (subaction_paths.left && act_attached->left.current.active) {                                               \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->left.current, data);             \
	}                                                                                                              \
	if (subaction_paths.right && act_attached->right.current.active) {                                             \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->right.current, data);            \
	}                                                                                                              \
	if (subaction_paths.gamepad && act_attached->gamepad.current.active) {                                         \
		get_xr_state_from_action_state_##TYPE(sess->sys->inst, &act_attached->gamepad.current, data);          \
	}

/*!
 * Clear the actual data members of the XrActionState* types, to have the
 * correct return value in case of the action being not active
 */
#define OXR_ACTION_RESET_XR_ACTION_STATE(data)                                                                         \
	do {                                                                                                           \
		data->isActive = XR_FALSE;                                                                             \
		data->changedSinceLastSync = XR_FALSE;                                                                 \
		data->lastChangeTime = 0;                                                                              \
		U_ZERO(&data->currentState);                                                                           \
	} while (0)

XrResult
oxr_action_get_boolean(struct oxr_logger *log,
                       struct oxr_session *sess,
                       uint32_t act_key,
                       struct oxr_subaction_paths subaction_paths,
                       XrActionStateBoolean *data)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

	OXR_ACTION_RESET_XR_ACTION_STATE(data);

	OXR_ACTION_GET_FILLER(bool);

	return oxr_session_success_result(sess);
}

XrResult
oxr_action_get_vector1f(struct oxr_logger *log,
                        struct oxr_session *sess,
                        uint32_t act_key,
                        struct oxr_subaction_paths subaction_paths,
                        XrActionStateFloat *data)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

	OXR_ACTION_RESET_XR_ACTION_STATE(data);

	OXR_ACTION_GET_FILLER(vec1);

	return oxr_session_success_result(sess);
}

XrResult
oxr_action_get_vector2f(struct oxr_logger *log,
                        struct oxr_session *sess,
                        uint32_t act_key,
                        struct oxr_subaction_paths subaction_paths,
                        XrActionStateVector2f *data)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

	OXR_ACTION_RESET_XR_ACTION_STATE(data);

	OXR_ACTION_GET_FILLER(vec2);

	return oxr_session_success_result(sess);
}

XrResult
oxr_action_get_pose(struct oxr_logger *log,
                    struct oxr_session *sess,
                    uint32_t act_key,
                    struct oxr_subaction_paths subaction_paths,
                    XrActionStatePose *data)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

	// For poses on the any path we select a single path.
	if (subaction_paths.any) {
		subaction_paths = act_attached->any_pose_subaction_path;
	}

	data->isActive = XR_FALSE;

	/*
	 * The sub path any is used as a catch all here to see if any
	 */
#define COMPUTE_ACTIVE(X)                                                                                              \
	if (subaction_paths.X) {                                                                                       \
		data->isActive |= act_attached->X.current.active;                                                      \
	}

	OXR_FOR_EACH_VALID_SUBACTION_PATH(COMPUTE_ACTIVE)
#undef COMPUTE_ACTIVE

	return oxr_session_success_result(sess);
}


/*
 *
 * Haptic feedback functions.
 *
 */

static void
set_action_output_vibration(struct oxr_session *sess,
                            struct oxr_action_cache *cache,
                            int64_t stop,
                            const XrHapticVibration *data)
{
	cache->stop_output_time = stop;

	union xrt_output_value value = {0};
	value.vibration.frequency = data->frequency;
	value.vibration.amplitude = data->amplitude;
	value.vibration.duration_ns = data->duration;

	for (uint32_t i = 0; i < cache->output_count; i++) {
		struct oxr_action_output *output = &cache->outputs[i];
		struct xrt_device *xdev = output->xdev;

		xrt_device_set_output(xdev, output->name, &value);
	}
}

XrResult
oxr_action_apply_haptic_feedback(struct oxr_logger *log,
                                 struct oxr_session *sess,
                                 uint32_t act_key,
                                 struct oxr_subaction_paths subaction_paths,
                                 const XrHapticBaseHeader *hapticEvent)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

	const XrHapticVibration *data = (const XrHapticVibration *)hapticEvent;

	// This should all be moved into the drivers.
	const int64_t min_pulse_time_ns = time_s_to_ns(0.1);
	int64_t now_ns = time_state_get_now(sess->sys->inst->timekeeping);
	int64_t stop_ns = 0;
	if (data->duration <= 0) {
		stop_ns = now_ns + min_pulse_time_ns;
	} else {
		stop_ns = now_ns + data->duration;
	}

#define SET_OUT_VIBRATION(X)                                                                                           \
	if (act_attached->X.current.active && (subaction_paths.X || subaction_paths.any)) {                            \
		set_action_output_vibration(sess, &act_attached->X, stop_ns, data);                                    \
	}

	OXR_FOR_EACH_SUBACTION_PATH(SET_OUT_VIBRATION)
#undef SET_OUT_VIBRATION
	return oxr_session_success_result(sess);
}

XrResult
oxr_action_stop_haptic_feedback(struct oxr_logger *log,
                                struct oxr_session *sess,
                                uint32_t act_key,
                                struct oxr_subaction_paths subaction_paths)
{
	struct oxr_action_attachment *act_attached = NULL;

	oxr_session_get_action_attachment(sess, act_key, &act_attached);
	if (act_attached == NULL) {
		return oxr_error(log, XR_ERROR_ACTIONSET_NOT_ATTACHED, "Action has not been attached to this session");
	}

#define STOP_VIBRATION(X)                                                                                              \
	if (act_attached->X.current.active && (subaction_paths.X || subaction_paths.any)) {                            \
		oxr_action_cache_stop_output(log, sess, &act_attached->X);                                             \
	}

	OXR_FOR_EACH_SUBACTION_PATH(STOP_VIBRATION)
#undef STOP_VIBRATION

	return oxr_session_success_result(sess);
}