// Copyright 2019-2020, Collabora, Ltd.
// SPDX-License-Identifier: BSL-1.0
/*!
 * @file
 * @brief  Session entrypoints for the OpenXR state tracker.
 * @author Jakob Bornecrantz <jakob@collabora.com>
 * @ingroup oxr_api
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>

#include "xrt/xrt_compiler.h"

#include "util/u_debug.h"

#include "oxr_objects.h"
#include "oxr_logger.h"
#include "oxr_two_call.h"

#include "oxr_api_funcs.h"
#include "oxr_api_verify.h"
#include "oxr_handle.h"
#include "oxr_chain.h"

XrResult
oxr_xrCreateSession(XrInstance instance, const XrSessionCreateInfo *createInfo, XrSession *out_session)
{
	XrResult ret;
	struct oxr_instance *inst;
	struct oxr_session *sess, **link;
	struct oxr_logger log;
	OXR_VERIFY_INSTANCE_AND_INIT_LOG(&log, instance, inst, "xrCreateSession");

	ret = oxr_verify_XrSessionCreateInfo(&log, inst, createInfo);
	if (ret != XR_SUCCESS) {
		return ret;
	}

	ret = oxr_session_create(&log, &inst->system, createInfo, &sess);
	if (ret != XR_SUCCESS) {
		return ret;
	}

	*out_session = oxr_session_to_openxr(sess);

	/* Add to session list */
	link = &inst->sessions;
	while (*link) {
		link = &(*link)->next;
	}
	*link = sess;

	return XR_SUCCESS;
}

XrResult
oxr_xrDestroySession(XrSession session)
{
	struct oxr_session *sess, **link;
	struct oxr_instance *inst;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrDestroySession");

	/* Remove from session list */
	inst = sess->sys->inst;
	link = &inst->sessions;
	while (*link != sess) {
		link = &(*link)->next;
	}
	*link = sess->next;

	return oxr_handle_destroy(&log, &sess->handle);
}

XrResult
oxr_xrBeginSession(XrSession session, const XrSessionBeginInfo *beginInfo)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrBeginSession");
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, beginInfo, XR_TYPE_SESSION_BEGIN_INFO);
	OXR_VERIFY_VIEW_CONFIG_TYPE(&log, sess->sys->inst, beginInfo->primaryViewConfigurationType);

	return oxr_session_begin(&log, sess, beginInfo);
}

XrResult
oxr_xrEndSession(XrSession session)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrEndSession");

	return oxr_session_end(&log, sess);
}

XrResult
oxr_xrWaitFrame(XrSession session, const XrFrameWaitInfo *frameWaitInfo, XrFrameState *frameState)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrWaitFrame");
	OXR_VERIFY_ARG_TYPE_CAN_BE_NULL(&log, frameWaitInfo, XR_TYPE_FRAME_WAIT_INFO);
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, frameState, XR_TYPE_FRAME_STATE);
	OXR_VERIFY_ARG_NOT_NULL(&log, frameState);

	return oxr_session_frame_wait(&log, sess, frameState);
}

XrResult
oxr_xrBeginFrame(XrSession session, const XrFrameBeginInfo *frameBeginInfo)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrBeginFrame");
	// NULL explicitly allowed here because it's a basically empty struct.
	OXR_VERIFY_ARG_TYPE_CAN_BE_NULL(&log, frameBeginInfo, XR_TYPE_FRAME_BEGIN_INFO);

	return oxr_session_frame_begin(&log, sess);
}

XrResult
oxr_xrEndFrame(XrSession session, const XrFrameEndInfo *frameEndInfo)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrEndFrame");
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, frameEndInfo, XR_TYPE_FRAME_END_INFO);

	return oxr_session_frame_end(&log, sess, frameEndInfo);
}

XrResult
oxr_xrRequestExitSession(XrSession session)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrRequestExitSession");

	return oxr_session_request_exit(&log, sess);
}

XrResult
oxr_xrLocateViews(XrSession session,
                  const XrViewLocateInfo *viewLocateInfo,
                  XrViewState *viewState,
                  uint32_t viewCapacityInput,
                  uint32_t *viewCountOutput,
                  XrView *views)
{
	struct oxr_session *sess;
	struct oxr_space *spc;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrLocateViews");
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, viewLocateInfo, XR_TYPE_VIEW_LOCATE_INFO);
	OXR_VERIFY_SPACE_NOT_NULL(&log, viewLocateInfo->space, spc);
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, viewState, XR_TYPE_VIEW_STATE);

	if (viewCapacityInput == 0) {
		OXR_VERIFY_ARG_NOT_NULL(&log, viewCountOutput);
	} else {
		OXR_VERIFY_ARG_NOT_NULL(&log, views);
	}

	return oxr_session_views(&log, sess, viewLocateInfo, viewState, viewCapacityInput, viewCountOutput, views);
}


/*
 *
 * XR_KHR_visibility_mask
 *
 */

#ifdef XR_KHR_visibility_mask

XrResult
oxr_xrGetVisibilityMaskKHR(XrSession session,
                           XrViewConfigurationType viewConfigurationType,
                           uint32_t viewIndex,
                           XrVisibilityMaskTypeKHR visibilityMaskType,
                           XrVisibilityMaskKHR *visibilityMask)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrGetVisibilityMaskKHR");

	return oxr_error(&log, XR_ERROR_HANDLE_INVALID, "Not implemented");
}

#endif


/*
 *
 * XR_EXT_performance_settings
 *
 */

#ifdef XR_EXT_performance_settings

XrResult
oxr_xrPerfSettingsSetPerformanceLevelEXT(XrSession session,
                                         XrPerfSettingsDomainEXT domain,
                                         XrPerfSettingsLevelEXT level)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrPerfSettingsSetPerformanceLevelEXT");

	return oxr_error(&log, XR_ERROR_HANDLE_INVALID, "Not implemented");
}

#endif


/*
 *
 * XR_EXT_thermal_query
 *
 */

#ifdef XR_EXT_thermal_query

XrResult
oxr_xrThermalGetTemperatureTrendEXT(XrSession session,
                                    XrPerfSettingsDomainEXT domain,
                                    XrPerfSettingsNotificationLevelEXT *notificationLevel,
                                    float *tempHeadroom,
                                    float *tempSlope)
{
	struct oxr_session *sess;
	struct oxr_logger log;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrThermalGetTemperatureTrendEXT");

	return oxr_error(&log, XR_ERROR_HANDLE_INVALID, "Not implemented");
}

/*
 *
 * XR_EXT_hand_tracking
 *
 */

static XrResult
oxr_hand_tracker_destroy_cb(struct oxr_logger *log, struct oxr_handle_base *hb)
{
	struct oxr_hand_tracker *hand_tracker = (struct oxr_hand_tracker *)hb;

	free(hand_tracker);

	return XR_SUCCESS;
}

XrResult
oxr_hand_tracker_create(struct oxr_logger *log,
                        struct oxr_session *sess,
                        const XrHandTrackerCreateInfoEXT *createInfo,
                        struct oxr_hand_tracker **out_hand_tracker)
{
	if (!oxr_system_get_hand_tracking_support(log, sess->sys->inst)) {
		return oxr_error(log, XR_ERROR_FEATURE_UNSUPPORTED, "System does not support hand tracking");
	}

	struct oxr_hand_tracker *hand_tracker = NULL;
	OXR_ALLOCATE_HANDLE_OR_RETURN(log, hand_tracker, OXR_XR_DEBUG_HTRACKER, oxr_hand_tracker_destroy_cb,
	                              &sess->handle);

	hand_tracker->sess = sess;
	hand_tracker->hand = createInfo->hand;
	hand_tracker->hand_joint_set = createInfo->handJointSet;

	//! @todo: Implement choice when more than one device has hand tracking
	for (uint32_t i = 0; i < sess->sys->num_xdevs; i++) {
		struct xrt_device *xdev = sess->sys->xdevs[i];

		if (!xdev->hand_tracking_supported) {
			continue;
		}

		for (uint32_t j = 0; j < xdev->num_inputs; j++) {
			struct xrt_input *input = &xdev->inputs[j];

			if ((input->name == XRT_INPUT_GENERIC_HAND_TRACKING_LEFT &&
			     createInfo->hand == XR_HAND_LEFT_EXT) ||
			    (input->name == XRT_INPUT_GENERIC_HAND_TRACKING_RIGHT &&
			     createInfo->hand == XR_HAND_RIGHT_EXT)) {
				hand_tracker->xdev = xdev;
				hand_tracker->input_name = input->name;
				break;
			}
		}

		if (hand_tracker->xdev != NULL) {
			break;
		}
	}

	*out_hand_tracker = hand_tracker;

	return XR_SUCCESS;
}

XrResult
oxr_xrCreateHandTrackerEXT(XrSession session,
                           const XrHandTrackerCreateInfoEXT *createInfo,
                           XrHandTrackerEXT *handTracker)
{
	struct oxr_hand_tracker *hand_tracker = NULL;
	struct oxr_session *sess = NULL;
	struct oxr_logger log;
	XrResult ret;
	OXR_VERIFY_SESSION_AND_INIT_LOG(&log, session, sess, "xrCreateHandTrackerEXT");
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, createInfo, XR_TYPE_HAND_TRACKER_CREATE_INFO_EXT);
	OXR_VERIFY_ARG_NOT_NULL(&log, handTracker);

	OXR_VERIFY_EXTENSION(&log, sess->sys->inst, EXT_hand_tracking);

	if (createInfo->hand != XR_HAND_LEFT_EXT && createInfo->hand != XR_HAND_RIGHT_EXT) {
		return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE, "Invalid hand value %d\n", createInfo->hand);
	}

	if (createInfo->handJointSet != XR_HAND_JOINT_SET_DEFAULT_EXT) {
		return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE, "Invalid handJointSet value %d\n",
		                 createInfo->handJointSet);
	}

	ret = oxr_hand_tracker_create(&log, sess, createInfo, &hand_tracker);
	if (ret != XR_SUCCESS) {
		return ret;
	}

	*handTracker = oxr_hand_tracker_to_openxr(hand_tracker);

	return XR_SUCCESS;
}

XrResult
oxr_xrDestroyHandTrackerEXT(XrHandTrackerEXT handTracker)
{
	struct oxr_hand_tracker *hand_tracker;
	struct oxr_logger log;
	OXR_VERIFY_HAND_TRACKER_AND_INIT_LOG(&log, handTracker, hand_tracker, "xrDestroyHandTrackerEXT");

	return oxr_handle_destroy(&log, &hand_tracker->handle);
}

XrResult
oxr_xrLocateHandJointsEXT(XrHandTrackerEXT handTracker,
                          const XrHandJointsLocateInfoEXT *locateInfo,
                          XrHandJointLocationsEXT *locations)
{
	struct oxr_hand_tracker *hand_tracker;
	struct oxr_space *spc;
	struct oxr_logger log;
	OXR_VERIFY_HAND_TRACKER_AND_INIT_LOG(&log, handTracker, hand_tracker, "xrLocateHandJointsEXT");
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, locateInfo, XR_TYPE_HAND_JOINTS_LOCATE_INFO_EXT);
	OXR_VERIFY_ARG_TYPE_AND_NOT_NULL(&log, locations, XR_TYPE_HAND_JOINT_LOCATIONS_EXT);
	OXR_VERIFY_SPACE_NOT_NULL(&log, locateInfo->baseSpace, spc);


	if (locateInfo->time <= (XrTime)0) {
		return oxr_error(&log, XR_ERROR_TIME_INVALID, "(time == %" PRIi64 ") is not a valid time.",
		                 locateInfo->time);
	}

	if (hand_tracker->hand_joint_set == XR_HAND_JOINT_SET_DEFAULT_EXT) {
		if (locations->jointCount != XR_HAND_JOINT_COUNT_EXT) {
			return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE, "joint count must be %d, not %d\n",
			                 XR_HAND_JOINT_COUNT_EXT, locations->jointCount);
		}
	};

	XrHandJointVelocitiesEXT *vel =
	    OXR_GET_OUTPUT_FROM_CHAIN(locations, XR_TYPE_HAND_JOINT_VELOCITIES_EXT, XrHandJointVelocitiesEXT);
	if (vel) {
		if (vel->jointCount <= 0) {
			return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE,
			                 "XrHandJointVelocitiesEXT joint count "
			                 "must be >0, is %d\n",
			                 vel->jointCount);
		}
		if (hand_tracker->hand_joint_set == XR_HAND_JOINT_SET_DEFAULT_EXT) {
			if (vel->jointCount != XR_HAND_JOINT_COUNT_EXT) {
				return oxr_error(&log, XR_ERROR_VALIDATION_FAILURE,
				                 "XrHandJointVelocitiesEXT joint count must "
				                 "be %d, not %d\n",
				                 XR_HAND_JOINT_COUNT_EXT, locations->jointCount);
			}
		}
	}

	return oxr_session_hand_joints(&log, hand_tracker, locateInfo, locations);
}

#endif