/*
 * Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
 *
 * The information contained herein is confidential property of Nordic Semiconductor. The use,
 * copying, transfer or disclosure of such information is prohibited except by express written
 * agreement with Nordic Semiconductor.
 *
 */

/**@file
 *
 * @defgroup ble_sdk_srv_nus_c   Nordic UART Service Client
 * @{
 * @ingroup  ble_sdk_srv
 * @brief    Nordic UART Service Client module.
 *
 * @details  This module contains the APIs and types exposed by the Nordic UART Service Client
 *           module. These APIs and types can be used by the application to perform discovery of
 *           the Nordic UART Service at the peer and interact with it.
 *
 * @note     The application must propagate BLE stack events to this module by calling
 *           ble_nus_c_on_ble_evt().
 *
 */


#ifndef BLE_NUS_C_H__
#define BLE_NUS_C_H__

#include "ble.h"
#include "ble_gatt.h"
#include <stdint.h>
#include <stdbool.h>

#define NUS_BASE_UUID                  {{0x9E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0xA3, 0xB5, 0x00, 0x00, 0x40, 0x6E}} /**< Used vendor specific UUID. */
#define BLE_UUID_NUS_SERVICE           0x0001                      /**< The UUID of the Nordic UART Service. */
#define BLE_UUID_NUS_TX_CHARACTERISTIC 0x0002                      /**< The UUID of the TX Characteristic. */
#define BLE_UUID_NUS_RX_CHARACTERISTIC 0x0003                      /**< The UUID of the RX Characteristic. */

#define BLE_NUS_MAX_DATA_LEN           (GATT_MTU_SIZE_DEFAULT - 3) /**< Maximum length of data (in bytes) that can be transmitted to the peer by the Nordic UART service module. */

/**
 * @defgroup hrs_c_enums Enumerations
 * @{
 */

/**@brief NUS Client event type. */
typedef enum 
{
    BLE_NUS_C_EVT_FOUND_NUS_TX_CHARACTERISTIC = 1, /**< Event indicating that the TX characteristic was found. */
    BLE_NUS_C_EVT_FOUND_NUS_RX_CHARACTERISTIC,     /**< Event indicating that the RX characteristic was found. */
    BLE_NUS_C_EVT_NUS_RX_EVT,                      /**< Event indicating that the central has received something from a peer. */
    BLE_NUS_C_EVT_DISCONNECTED                     /**< Event indicating that the NUS server has disconnected. */
} ble_nus_c_evt_type_t;

/** @} */


/**
 * @defgroup hrs_c_structs Structures
 * @{
 */

/**@brief Structure containing the NUS event data received from the peer. */
typedef struct {
    ble_nus_c_evt_type_t evt_type;
    uint8_t              * p_data;
    uint8_t              data_len;
} ble_nus_c_evt_t;


// Forward declaration of the ble_nus_t type.
typedef struct ble_nus_c_s ble_nus_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 to receive events.
 */
typedef void (* ble_nus_c_evt_handler_t)(ble_nus_c_t * p_ble_nus_c, const ble_nus_c_evt_t * p_evt);


/**@brief NUS Client structure.
 */
struct ble_nus_c_s
{
    uint8_t                 uuid_type;          /**< UUID type. */
    uint16_t                conn_handle;        /**< Connection handle as provided by the SoftDevice. */
    uint16_t                nus_rx_handle;      /**< Handle of the NUS RX characteristic as provided by a discovery. */
    uint16_t                nus_rx_cccd_handle; /**< Handle of the CCCD of the NUS RX characteristic as provided by a discovery. */
    uint16_t                nus_tx_handle;      /**< Handle of the NUS TX characteristic as provided by a discovery. */
    ble_nus_c_evt_handler_t evt_handler;        /**< Application event handler to be called when there is an event related to the NUS. */
};

/**@brief NUS Client initialization structure.
 */
typedef struct {
    ble_nus_c_evt_handler_t evt_handler;
} ble_nus_c_init_t;

/** @} */


/**
 * @defgroup nus_c_functions Functions
 * @{
 */

/**@brief     Function for initializing the Nordic UART client module.
 *
 * @details   This function registers with the Database Discovery module
 *            for the NUS. Doing so will make the Database Discovery
 *            module look for the presence of a NUS instance at the peer when a
 *            discovery is started.
 *
 * @param[in] p_ble_nus_c      Pointer to the NUS client structure.
 * @param[in] p_ble_nus_c_init Pointer to the NUS initialization structure containing the
 *                             initialization information.
 *
 * @retval    NRF_SUCCESS If the module was initialized successfully. Otherwise, an error 
 *                        code is returned. This function
 *                        propagates the error code returned by the Database Discovery module API
 *                        @ref ble_db_discovery_evt_register.
 */
uint32_t ble_nus_c_init(ble_nus_c_t * p_ble_nus_c, ble_nus_c_init_t * p_ble_nus_c_init);

/**@brief     Function for handling BLE events from the SoftDevice.
 *
 * @details   This function handles the BLE events received from the SoftDevice. If a BLE
 *            event is relevant to the NUS module, it is used to update
 *            internal variables and, if necessary, send events to the application.
 *
 * @param[in] p_ble_nus_c Pointer to the NUS client structure.
 * @param[in] p_ble_evt   Pointer to the BLE event.
 */
void ble_nus_c_on_ble_evt(ble_nus_c_t * p_ble_nus_c, const ble_evt_t * p_ble_evt);

/**@brief   Function for requesting the peer to start sending notification of RX characteristic.
 *
 * @details This function enables notifications of the NUS RX characteristic at the peer
 *          by writing to the CCCD of the NUS RX characteristic.
 *
 * @param   p_ble_nus_c Pointer to the NUS client structure.
 *
 * @retval  NRF_SUCCESS If the SoftDevice has been requested to write to the CCCD of the peer.
 *                      Otherwise, an error code is returned. This function propagates the error  
 *                      code returned by the SoftDevice API @ref sd_ble_gattc_write.
 */
uint32_t ble_nus_c_rx_notif_enable(ble_nus_c_t * p_ble_nus_c);

/**@brief Function for sending a string to the server.
 *
 * @details This function writes the TX characteristic of the server.
 *
 * @param[in] p_ble_nus_c Pointer to the NUS client structure.
 * @param[in] p_string    String to be sent.
 * @param[in] length      Length of the string.
 *
 * @retval NRF_SUCCESS If the string was sent successfully. Otherwise, an error code is returned.
 */
uint32_t ble_nus_c_string_send(ble_nus_c_t * p_ble_nus_c, uint8_t * p_string, uint16_t length);

/** @} */

#endif // BLE_NUS_C_H__

/** @} */
