/*
 * Copyright (c) 2016 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#ifndef ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_HRS_H_
#define ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_HRS_H_

/**
 * @brief Heart Rate Service (HRS)
 * @defgroup bt_hrs Heart Rate Service (HRS)
 * @ingroup bluetooth
 * @{
 *
 * [Experimental] Users should note that the APIs can change
 * as a part of ongoing development.
 */

#include <stdint.h>

#include <zephyr/sys/slist.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief Server shall restart the accumulation of energy expended from zero
 */
#define BT_HRS_CONTROL_POINT_RESET_ENERGY_EXPANDED_REQ 0x01

/** @brief Heart rate service callback structure */
struct bt_hrs_cb {
	/** @brief Heart rate notifications changed
	 *
	 * @param enabled Flag that is true if notifications were enabled, false
	 *                if they were disabled.
	 */
	void (*ntf_changed)(bool enabled);

	/**
	 * @brief Heart rate control point write callback
	 *
	 * @note if Server supports the Energy Expended feature then application
	 * shall implement and support @ref BT_HRS_CONTROL_POINT_RESET_ENERGY_EXPANDED_REQ
	 * request code
	 *
	 * @param request control point request code
	 *
	 * @return 0 on successful handling of control point request
	 * @return -ENOTSUP if not supported. It can be used to pass handling to other
	 *         listeners in case of multiple listeners
	 * @return other negative error codes will result in immediate error response
	 */
	int (*ctrl_point_write)(uint8_t request);

	/** Internal member to form a list of callbacks */
	sys_snode_t _node;
};

/** @brief Heart rate service callback register
 *
 * This function will register callbacks that will be called in
 * certain events related to Heart rate service.
 *
 * @param cb Pointer to callbacks structure. Must point to memory that remains valid
 * until unregistered.
 *
 * @return 0 on success
 * @return -EINVAL in case @p cb is NULL
 */
int bt_hrs_cb_register(struct bt_hrs_cb *cb);

/** @brief Heart rate service callback unregister
 *
 * This function will unregister callback from Heart rate service.
 *
 * @param cb Pointer to callbacks structure
 *
 * @return 0 on success
 * @return -EINVAL in case @p cb is NULL
 * @return -ENOENT in case the @p cb was not found in registered callbacks
 */
int bt_hrs_cb_unregister(struct bt_hrs_cb *cb);

/** @brief Notify heart rate measurement.
 *
 * This will send a GATT notification to all current subscribers.
 *
 *  @param heartrate The heartrate measurement in beats per minute.
 *
 *  @return Zero in case of success and error code in case of error.
 */
int bt_hrs_notify(uint16_t heartrate);

#ifdef __cplusplus
}
#endif

/**
 * @}
 */

#endif /* ZEPHYR_INCLUDE_BLUETOOTH_SERVICES_HRS_H_ */