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  /**@file
   *
   * @defgroup ble_hrs_c Heart Rate Service Client
   * @{
   * @ingroup  ble_sdk_srv
   * @brief    Heart Rate Service Client module.
   *
   * @details  This module contains the APIs and types exposed by the Heart Rate Service Client
   *           module. These APIs and types can be used by the application to perform discovery of
   *           Heart Rate Service at the peer and interact with it.
   *
   * @warning  Currently this module only has support for Heart Rate Measurement characteristic. This
   *           means that it will be able to enable notification of the characteristic at the peer and
   *           be able to receive Heart Rate Measurement notifications from the peer. It does not
   *           support the Body Sensor Location and the Heart Rate Control Point characteristics.
   *           When a Heart Rate Measurement is received, this module will decode only the
   *           Heart Rate Measurement Value (both 8 bit and 16 bit) field from it and provide it to
   *           the application.
   *
   * @note    The application must register this module as BLE event observer using the
   *          NRF_SDH_BLE_OBSERVER macro. Example:
   *          @code
   *              ble_hrs_c_t instance;
   *              NRF_SDH_BLE_OBSERVER(anything, BLE_HRS_C_BLE_OBSERVER_PRIO,
   *                                   ble_hrs_c_on_ble_evt, &instance);
   *          @endcode
   */
  
  #ifndef BLE_HRS_C_H__
  #define BLE_HRS_C_H__
  
  #include <stdint.h>
  #include "ble.h"
  #include "ble_db_discovery.h"
  #include "sdk_config.h"
  #include "nrf_sdh_ble.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**@brief   Macro for defining a ble_hrs_c instance.
   *
   * @param   _name   Name of the instance.
   * @hideinitializer
   */
  #define BLE_HRS_C_DEF(_name)                                                                        \
  static ble_hrs_c_t _name;                                                                           \
  NRF_SDH_BLE_OBSERVER(_name ## _obs,                                                                 \
                       BLE_HRS_C_BLE_OBSERVER_PRIO,                                                   \
                       ble_hrs_c_on_ble_evt, &_name)
  
  /** @brief  Maximum number of RR intervals to be decoded for each HRM notifications (any extra RR intervals will be ignored).
   *
   * This define should be defined in the sdk_config.h file to override the default.
   */
  #ifndef BLE_HRS_C_RR_INTERVALS_MAX_CNT
  #define BLE_HRS_C_RR_INTERVALS_MAX_CNT 20
  #endif
  
  
  /**
   * @defgroup hrs_c_enums Enumerations
   * @{
   */
  
  /**@brief HRS Client event type. */
  typedef enum
  {
      BLE_HRS_C_EVT_DISCOVERY_COMPLETE = 1,  /**< Event indicating that the Heart Rate Service has been discovered at the peer. */
      BLE_HRS_C_EVT_HRM_NOTIFICATION         /**< Event indicating that a notification of the Heart Rate Measurement characteristic has been received from the peer. */
  } ble_hrs_c_evt_type_t;
  
  /** @} */
  
  /**
   * @defgroup hrs_c_structs Structures
   * @{
   */
  
  /**@brief Structure containing the heart rate measurement received from the peer. */
  typedef struct
  {
      uint16_t hr_value;                                        /**< Heart Rate Value. */
      uint8_t  rr_intervals_cnt;                                /**< Number of RR intervals. */
      uint16_t rr_intervals[BLE_HRS_C_RR_INTERVALS_MAX_CNT];    /**< RR intervals. */
  } ble_hrm_t;
  
  /**@brief Structure containing the handles related to the Heart Rate Service found on the peer. */
  typedef struct
  {
      uint16_t hrm_cccd_handle;  /**< Handle of the CCCD of the Heart Rate Measurement characteristic. */
      uint16_t hrm_handle;       /**< Handle of the Heart Rate Measurement characteristic as provided by the SoftDevice. */
  } hrs_db_t;
  
  /**@brief Heart Rate Event structure. */
  typedef struct
  {
      ble_hrs_c_evt_type_t evt_type;    /**< Type of the event. */
      uint16_t             conn_handle; /**< Connection handle on which the Heart Rate service was discovered on the peer device..*/
      union
      {
          hrs_db_t  peer_db;            /**< Heart Rate related handles found on the peer device.. This will be filled if the evt_type is @ref BLE_HRS_C_EVT_DISCOVERY_COMPLETE.*/
          ble_hrm_t hrm;                /**< Heart rate measurement received. This will be filled if the evt_type is @ref BLE_HRS_C_EVT_HRM_NOTIFICATION. */
      } params;
  } ble_hrs_c_evt_t;
  
  /** @} */
  
  /**
   * @defgroup hrs_c_types Types
   * @{
   */
  
  // Forward declaration of the ble_bas_t type.
  typedef struct ble_hrs_c_s ble_hrs_c_t;
  
  /**@brief   Event handler type.
   *
   * @details This is the type of the event handler that should be provided by the application
   *          of this module in order to receive events.
   */
  typedef void (* ble_hrs_c_evt_handler_t) (ble_hrs_c_t * p_ble_hrs_c, ble_hrs_c_evt_t * p_evt);
  
  /** @} */
  
  /**
   * @addtogroup hrs_c_structs
   * @{
   */
  
  /**@brief Heart Rate Client structure.
   */
  struct ble_hrs_c_s
  {
      uint16_t                conn_handle;      /**< Connection handle as provided by the SoftDevice. */
      hrs_db_t                peer_hrs_db;      /**< Handles related to HRS on the peer*/
      ble_hrs_c_evt_handler_t evt_handler;      /**< Application event handler to be called when there is an event related to the heart rate service. */
  };
  
  /**@brief Heart Rate Client initialization structure.
   */
  typedef struct
  {
      ble_hrs_c_evt_handler_t evt_handler;  /**< Event handler to be called by the Heart Rate Client module whenever there is an event related to the Heart Rate Service. */
  } ble_hrs_c_init_t;
  
  /** @} */
  
  
  /**
   * @defgroup hrs_c_functions Functions
   * @{
   */
  
  /**@brief     Function for initializing the heart rate client module.
   *
   * @details   This function will register with the DB Discovery module. There it
   *            registers for the Heart Rate Service. Doing so will make the DB Discovery
   *            module look for the presence of a Heart Rate Service instance at the peer when a
   *            discovery is started.
   *
   * @param[in] p_ble_hrs_c      Pointer to the heart rate client structure.
   * @param[in] p_ble_hrs_c_init Pointer to the heart rate initialization structure containing the
   *                             initialization information.
   *
   * @retval    NRF_SUCCESS On successful initialization. Otherwise an error code. This function
   *                        propagates the error code returned by the Database Discovery module API
   *                        @ref ble_db_discovery_evt_register.
   */
  uint32_t ble_hrs_c_init(ble_hrs_c_t * p_ble_hrs_c, ble_hrs_c_init_t * p_ble_hrs_c_init);
  
  
  /**@brief     Function for handling BLE events from the SoftDevice.
   *
   * @details   This function will handle the BLE events received from the SoftDevice. If a BLE
   *            event is relevant to the Heart Rate Client module, then it uses it to update
   *            interval variables and, if necessary, send events to the application.
   *
   * @param[in] p_ble_evt     Pointer to the BLE event.
   * @param[in] p_context     Pointer to the heart rate client structure.
   */
  void ble_hrs_c_on_ble_evt(ble_evt_t const * p_ble_evt, void * p_context);
  
  
  /**@brief   Function for requesting the peer to start sending notification of Heart Rate
   *          Measurement.
   *
   * @details This function will enable to notification of the Heart Rate Measurement at the peer
   *          by writing to the CCCD of the Heart Rate Measurement Characteristic.
   *
   * @param   p_ble_hrs_c Pointer to the heart rate client structure.
   *
   * @retval  NRF_SUCCESS If the SoftDevice has been requested to write to the CCCD of the peer.
   *                      Otherwise, an error code. This function propagates the error code returned
   *                      by the SoftDevice API @ref sd_ble_gattc_write.
   */
  uint32_t ble_hrs_c_hrm_notif_enable(ble_hrs_c_t * p_ble_hrs_c);
  
  
  /**@brief     Function for handling events from the database discovery module.
   *
   * @details   Call this function when getting a callback event from the DB discovery modue.
   *            This function will handle an event from the database discovery module, and determine
   *            if it relates to the discovery of heart rate service at the peer. If so, it will
   *            call the application's event handler indicating that the heart rate service has been
   *            discovered at the peer. It also populates the event with the service related
   *            information before providing it to the application.
   *
   * @param[in] p_ble_hrs_c Pointer to the heart rate client structure instance to associate.
   * @param[in] p_evt Pointer to the event received from the database discovery module.
   *
   */
  void ble_hrs_on_db_disc_evt(ble_hrs_c_t * p_ble_hrs_c, const ble_db_discovery_evt_t * p_evt);
  
  
  /**@brief     Function for assigning a handles to a this instance of hrs_c.
   *
   * @details   Call this function when a link has been established with a peer to
   *            associate this link to this instance of the module. This makes it
   *            possible to handle several link and associate each link to a particular
   *            instance of this module.The connection handle and attribute handles will be
   *            provided from the discovery event @ref BLE_HRS_C_EVT_DISCOVERY_COMPLETE.
   *
   * @param[in] p_ble_hrs_c        Pointer to the heart rate client structure instance to associate.
   * @param[in] conn_handle        Connection handle to associated with the given Heart Rate Client Instance.
   * @param[in] p_peer_hrs_handles Attribute handles for the HRS server you want this HRS_C client to
   *                               interact with.
   */
  uint32_t ble_hrs_c_handles_assign(ble_hrs_c_t *    p_ble_hrs_c,
                                    uint16_t         conn_handle,
                                    const hrs_db_t * p_peer_hrs_handles);
  
  /** @} */ // End tag for Function group.
  
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif // BLE_HRS_C_H__
  
  /** @} */ // End tag for the file.
  