text: /**
   * Copyright (c) 2012 - 2017, Nordic Semiconductor ASA
   * 
   * All rights reserved.
   * 
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   * 
   * 1. Redistributions of source code must retain the above copyright notice, this
   *    list of conditions and the following disclaimer.
   * 
   * 2. Redistributions in binary form, except as embedded into a Nordic
   *    Semiconductor ASA integrated circuit in a product or a software update for
   *    such product, must reproduce the above copyright notice, this list of
   *    conditions and the following disclaimer in the documentation and/or other
   *    materials provided with the distribution.
   * 
   * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
   *    contributors may be used to endorse or promote products derived from this
   *    software without specific prior written permission.
   * 
   * 4. This software, with or without modification, must only be used with a
   *    Nordic Semiconductor ASA integrated circuit.
   * 
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   *    engineered, decompiled, modified and/or disassembled.
   * 
   * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
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   */
  /** @file
   *
   * @defgroup ble_sdk_apple_notification_main main.c
   * @{
   * @ingroup ble_sdk_app_apple_notification
   * @brief Apple Notification Client Sample Application main file. Disclaimer:
   * This client implementation of the Apple Notification Center Service can and
   * will be changed at any time by Nordic Semiconductor ASA.
   *
   * Server implementations such as the ones found in iOS can be changed at any
   * time by Apple and may cause this client implementation to stop working.
   *
   * This file contains the source code for a sample application using the Apple
   * Notification Center Service Client.
   */
  
  #include <stdbool.h>
  #include <stdint.h>
  #include <string.h>
  #include <stdio.h>
  
  #include "nrf_ble_ancs_c.h"
  #include "ble_db_discovery.h"
  #include "nordic_common.h"
  #include "nrf.h"
  #include "app_error.h"
  #include "ble_hci.h"
  #include "ble_gap.h"
  #include "ble_advdata.h"
  #include "ble_advertising.h"
  #include "ble_conn_params.h"
  #include "peer_manager.h"
  #include "app_timer.h"
  #include "nrf_soc.h"
  #include "bsp.h"
  #include "bsp_btn_ble.h"
  #include "softdevice_handler.h"
  #include "fds.h"
  #include "fstorage.h"
  #include "nrf_delay.h"
  #include "app_scheduler.h"
  #include "app_timer.h"
  #include "ble_conn_state.h"
  #include "nrf_ble_gatt.h"
  
  #define NRF_LOG_MODULE_NAME "APP"
  #include "nrf_log.h"
  #include "nrf_log_ctrl.h"
  
  
  #if BUTTONS_NUMBER < 2
  #error "Not enough resources on board"
  #endif
  
  #define ATTR_DATA_SIZE                 BLE_ANCS_ATTR_DATA_MAX                      /**< Allocated size for attribute data. */
  
  #define DISPLAY_MESSAGE_BUTTON_ID      1                                           /**< Button used to request notification attributes. */
  
  #define DEVICE_NAME                    "ANCS"                                      /**< Name of the device. Will be included in the advertising data. */
  #define APP_ADV_FAST_INTERVAL          40                                          /**< The advertising interval (in units of 0.625 ms). The default value corresponds to 25 ms. */
  #define APP_ADV_SLOW_INTERVAL          3200                                        /**< Slow advertising interval (in units of 0.625 ms). The default value corresponds to 2 seconds. */
  #define APP_ADV_FAST_TIMEOUT           180                                         /**< The advertising time-out in units of seconds. */
  #define APP_ADV_SLOW_TIMEOUT           180                                         /**< The advertising time-out in units of seconds. */
  #define ADV_INTERVAL_FAST_PERIOD       30                                          /**< The duration of the fast advertising period (in seconds). */
  
  #define MIN_CONN_INTERVAL              MSEC_TO_UNITS(500, UNIT_1_25_MS)            /**< Minimum acceptable connection interval (0.5 seconds). */
  #define MAX_CONN_INTERVAL              MSEC_TO_UNITS(1000, UNIT_1_25_MS)           /**< Maximum acceptable connection interval (1 second). */
  #define SLAVE_LATENCY                  0                                           /**< Slave latency. */
  #define CONN_SUP_TIMEOUT               MSEC_TO_UNITS(4000, UNIT_10_MS)             /**< Connection supervisory time-out (4 seconds). */
  
  #define FIRST_CONN_PARAMS_UPDATE_DELAY APP_TIMER_TICKS(5000)  /**< Time from initiating an event (connect or start of notification) to the first time sd_ble_gap_conn_param_update is called (5 seconds). */
  #define NEXT_CONN_PARAMS_UPDATE_DELAY  APP_TIMER_TICKS(30000) /**< Time between each call to sd_ble_gap_conn_param_update after the first (30 seconds). */
  #define MAX_CONN_PARAMS_UPDATE_COUNT   3                                           /**< Number of attempts before giving up the connection parameter negotiation. */
  
  #define MESSAGE_BUFFER_SIZE            18                                          /**< Size of buffer holding optional messages in notifications. */
  
  #define SECURITY_REQUEST_DELAY         APP_TIMER_TICKS(1500)  /**< Delay after connection until security request is sent, if necessary (ticks). */
  
  #define SEC_PARAM_BOND                 1                                           /**< Perform bonding. */
  #define SEC_PARAM_MITM                 0                                           /**< Man In The Middle protection not required. */
  #define SEC_PARAM_LESC                 0                                           /**< LE Secure Connections not enabled. */
  #define SEC_PARAM_KEYPRESS             0                                           /**< Keypress notifications not enabled. */
  #define SEC_PARAM_IO_CAPABILITIES      BLE_GAP_IO_CAPS_NONE                        /**< No I/O capabilities. */
  #define SEC_PARAM_OOB                  0                                           /**< Out Of Band data not available. */
  #define SEC_PARAM_MIN_KEY_SIZE         7                                           /**< Minimum encryption key size. */
  #define SEC_PARAM_MAX_KEY_SIZE         16                                          /**< Maximum encryption key size. */
  
  #define DEAD_BEEF                      0xDEADBEEF                                  /**< Value used as error code on stack dump. Can be used to identify stack location on stack unwind. */
  
  #define SCHED_MAX_EVENT_DATA_SIZE      MAX(APP_TIMER_SCHED_EVENT_DATA_SIZE, \
                                             BLE_STACK_HANDLER_SCHED_EVT_SIZE)       /**< Maximum size of scheduler events. */
  #ifdef SVCALL_AS_NORMAL_FUNCTION
  #define SCHED_QUEUE_SIZE               20                                          /**< Maximum number of events in the scheduler queue. More is needed in case of Serialization. */
  #else
  #define SCHED_QUEUE_SIZE               10                                          /**< Maximum number of events in the scheduler queue. */
  #endif
  
  static pm_peer_id_t   m_whitelist_peers[BLE_GAP_WHITELIST_ADDR_MAX_COUNT];  /**< List of peers currently in the whitelist. */
  static uint32_t       m_whitelist_peer_cnt;                                 /**< Number of peers currently in the whitelist. */
  static bool           m_is_wl_changed;                                      /**< Indicates if the whitelist has been changed since last time it has been updated in the Peer Manager. */
  
  
  /**@brief String literals for the iOS notification categories. used then printing to UART. */
  static const char * lit_catid[BLE_ANCS_NB_OF_CATEGORY_ID] =
  {
      "Other",
      "Incoming Call",
      "Missed Call",
      "Voice Mail",
      "Social",
      "Schedule",
      "Email",
      "News",
      "Health And Fitness",
      "Business And Finance",
      "Location",
      "Entertainment"
  };
  
  
  /**@brief String literals for the iOS notification event types. Used then printing to UART. */
  static const char * lit_eventid[BLE_ANCS_NB_OF_EVT_ID] =
  {
      "Added",
      "Modified",
      "Removed"
  };
  
  
  /**@brief String literals for the iOS notification attribute types. Used when printing to UART. */
  static const char * lit_attrid[BLE_ANCS_NB_OF_NOTIF_ATTR] =
  {
      "App Identifier",
      "Title",
      "Subtitle",
      "Message",
      "Message Size",
      "Date",
      "Positive Action Label",
      "Negative Action Label"
  };
  
  
  /**@brief String literals for the iOS notification attribute types. Used When printing to UART. */
  static const char * lit_appid[BLE_ANCS_NB_OF_APP_ATTR] =
  {
      "Display Name"
  };
  
  
  static ble_ancs_c_t       m_ancs_c;                                     /**< Structure used to identify the Apple Notification Service Client. */
  static ble_db_discovery_t m_ble_db_discovery;                           /**< Structure used to identify the DB Discovery module. */
  static nrf_ble_gatt_t     m_gatt;                                       /**< GATT module instance. */
  static pm_peer_id_t       m_peer_id;                                    /**< Device reference handle to the current bonded central. */
  static uint16_t           m_cur_conn_handle = BLE_CONN_HANDLE_INVALID;  /**< Handle of the current connection. */
  
  APP_TIMER_DEF(m_sec_req_timer_id);                                      /**< Security request timer. The timer lets us start pairing request if one does not arrive from the Central. */
  
  static ble_ancs_c_evt_notif_t m_notification_latest;                    /**< Local copy to keep track of the newest arriving notifications. */
  static ble_ancs_c_attr_t      m_notif_attr_latest;                      /**< Local copy of the newest notification attribute. */
  static ble_ancs_c_attr_t      m_notif_attr_app_id_latest;               /**< Local copy of the newest app attribute. */
  
  static uint8_t m_attr_appid[ATTR_DATA_SIZE];                            /**< Buffer to store attribute data. */
  
  static uint8_t m_attr_title[ATTR_DATA_SIZE];                            /**< Buffer to store attribute data. */
  static uint8_t m_attr_subtitle[ATTR_DATA_SIZE];                         /**< Buffer to store attribute data. */
  static uint8_t m_attr_message[ATTR_DATA_SIZE];                          /**< Buffer to store attribute data. */
  static uint8_t m_attr_message_size[ATTR_DATA_SIZE];                     /**< Buffer to store attribute data. */
  static uint8_t m_attr_date[ATTR_DATA_SIZE];                             /**< Buffer to store attribute data. */
  static uint8_t m_attr_posaction[ATTR_DATA_SIZE];                        /**< Buffer to store attribute data. */
  static uint8_t m_attr_negaction[ATTR_DATA_SIZE];                        /**< Buffer to store attribute data. */
  
  static uint8_t m_attr_disp_name[ATTR_DATA_SIZE];                        /**< Buffer to store attribute data. */
  
  static void delete_bonds(void);
  
  /**@brief Callback function for handling asserts in the SoftDevice.
   *
   * @details This function is called in case of an assert in the SoftDevice.
   *
   * @warning This handler is an example only and does not fit a final product.
   *          You must analyze how your product should react to asserts.
   * @warning On assert from the SoftDevice, the system can recover only on reset.
   *
   * @param[in] line_num   Line number of the failing ASSERT call.
   * @param[in] file_name  File name of the failing ASSERT call.
   */
  void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
  {
      app_error_handler(DEAD_BEEF, line_num, p_file_name);
  }
  
  
  /**@brief Fetch the list of peer manager peer IDs.
   *
   * @param[inout] p_peers   The buffer where to store the list of peer IDs.
   * @param[inout] p_size    In: The size of the @p p_peers buffer.
   *                         Out: The number of peers copied in the buffer.
   */
  static void peer_list_get(pm_peer_id_t * p_peers, uint32_t * p_size)
  {
      pm_peer_id_t peer_id;
      uint32_t     peers_to_copy;
  
      peers_to_copy = (*p_size < BLE_GAP_WHITELIST_ADDR_MAX_COUNT) ?
                       *p_size : BLE_GAP_WHITELIST_ADDR_MAX_COUNT;
  
      peer_id = pm_next_peer_id_get(PM_PEER_ID_INVALID);
      *p_size = 0;
  
      while ((peer_id != PM_PEER_ID_INVALID) && (peers_to_copy--))
      {
          p_peers[(*p_size)++] = peer_id;
          peer_id = pm_next_peer_id_get(peer_id);
      }
  }
  
  
  /**@brief Function for starting advertising.
   */
  static void advertising_start(bool erase_bonds)
  {
      if (erase_bonds == true)
      {
          delete_bonds();
          // Advertising is started by PM_EVT_PEERS_DELETE_SUCCEEDED event.
      }
      else
      {
          ret_code_t ret;
  
          memset(m_whitelist_peers, PM_PEER_ID_INVALID, sizeof(m_whitelist_peers));
          m_whitelist_peer_cnt = (sizeof(m_whitelist_peers) / sizeof(pm_peer_id_t));
  
          peer_list_get(m_whitelist_peers, &m_whitelist_peer_cnt);
  
          ret = pm_whitelist_set(m_whitelist_peers, m_whitelist_peer_cnt);
          APP_ERROR_CHECK(ret);
  
          // Setup the device identies list.
          // Some SoftDevices do not support this feature.
          ret = pm_device_identities_list_set(m_whitelist_peers, m_whitelist_peer_cnt);
          if (ret != NRF_ERROR_NOT_SUPPORTED)
          {
              APP_ERROR_CHECK(ret);
          }
  
          m_is_wl_changed = false;
  
          ret = ble_advertising_start(BLE_ADV_MODE_FAST);
          APP_ERROR_CHECK(ret);
      }
  }
  
  
  /**@brief Function for handling Peer Manager events.
   *
   * @param[in] p_evt  Peer Manager event.
   */
  static void pm_evt_handler(pm_evt_t const * p_evt)
  {
      ret_code_t ret;
  
      switch (p_evt->evt_id)
      {
          case PM_EVT_BONDED_PEER_CONNECTED:
          {
              NRF_LOG_DEBUG("Connected to previously bonded device\r\n");
              m_peer_id = p_evt->peer_id;
          } break; // PM_EVT_BONDED_PEER_CONNECTED
  
          case PM_EVT_CONN_SEC_SUCCEEDED:
          {
              NRF_LOG_INFO("Connection secured: role: %d, conn_handle: 0x%x, procedure: %d.\r\n",
                           ble_conn_state_role(p_evt->conn_handle),
                           p_evt->conn_handle,
                           p_evt->params.conn_sec_succeeded.procedure);
  
              m_peer_id = p_evt->peer_id;
  
              // Note: You should check on what kind of white list policy your application should use.
              if (p_evt->params.conn_sec_succeeded.procedure == PM_LINK_SECURED_PROCEDURE_BONDING)
              {
                  NRF_LOG_DEBUG("New Bond, add the peer to the whitelist if possible\r\n");
                  NRF_LOG_DEBUG("\tm_whitelist_peer_cnt %d, MAX_PEERS_WLIST %d\r\n",
                                 m_whitelist_peer_cnt + 1,
                                 BLE_GAP_WHITELIST_ADDR_MAX_COUNT);
  
                  if (m_whitelist_peer_cnt < BLE_GAP_WHITELIST_ADDR_MAX_COUNT)
                  {
                      // Bonded to a new peer, add it to the whitelist.
                      m_whitelist_peers[m_whitelist_peer_cnt++] = m_peer_id;
                      m_is_wl_changed = true;
                  }
              }
              // Discover peer's services.
              memset(&m_ble_db_discovery, 0x00, sizeof(m_ble_db_discovery));
              ret  = ble_db_discovery_start(&m_ble_db_discovery, p_evt->conn_handle);
              APP_ERROR_CHECK(ret);
          } break;
  
          case PM_EVT_CONN_SEC_FAILED:
          {
              /* Often, when securing fails, it shouldn't be restarted, for security reasons.
               * Other times, it can be restarted directly.
               * Sometimes it can be restarted, but only after changing some Security Parameters.
               * Sometimes, it cannot be restarted until the link is disconnected and reconnected.
               * Sometimes it is impossible, to secure the link, or the peer device does not support it.
               * How to handle this error is highly application dependent. */
          } break;
  
          case PM_EVT_CONN_SEC_CONFIG_REQ:
          {
              // Reject pairing request from an already bonded peer.
              pm_conn_sec_config_t conn_sec_config = {.allow_repairing = false};
              pm_conn_sec_config_reply(p_evt->conn_handle, &conn_sec_config);
          } break;
  
          case PM_EVT_STORAGE_FULL:
          {
              // Run garbage collection on the flash.
              ret = fds_gc();
              if (ret == FDS_ERR_BUSY || ret == FDS_ERR_NO_SPACE_IN_QUEUES)
              {
                  // Retry.
              }
              else
              {
                  APP_ERROR_CHECK(ret);
              }
          } break;
  
          case PM_EVT_PEERS_DELETE_SUCCEEDED:
          {
              advertising_start(false);
          } break;
  
          case PM_EVT_LOCAL_DB_CACHE_APPLY_FAILED:
          {
              // The local database has likely changed, send service changed indications.
              pm_local_database_has_changed();
          } break;
  
          case PM_EVT_PEER_DATA_UPDATE_FAILED:
          {
              // Assert.
              APP_ERROR_CHECK(p_evt->params.peer_data_update_failed.error);
          } break;
  
          case PM_EVT_PEER_DELETE_FAILED:
          {
              // Assert.
              APP_ERROR_CHECK(p_evt->params.peer_delete_failed.error);
          } break;
  
          case PM_EVT_PEERS_DELETE_FAILED:
          {
              // Assert.
              APP_ERROR_CHECK(p_evt->params.peers_delete_failed_evt.error);
          } break;
  
          case PM_EVT_ERROR_UNEXPECTED:
          {
              // Assert.
              APP_ERROR_CHECK(p_evt->params.error_unexpected.error);
          } break;
  
          case PM_EVT_CONN_SEC_START:
          case PM_EVT_PEER_DATA_UPDATE_SUCCEEDED:
          case PM_EVT_PEER_DELETE_SUCCEEDED:
          case PM_EVT_LOCAL_DB_CACHE_APPLIED:
          case PM_EVT_SERVICE_CHANGED_IND_SENT:
          case PM_EVT_SERVICE_CHANGED_IND_CONFIRMED:
          default:
              break;
      }
  }
  
  
  /**@brief Function for handling the security request timer time-out.
   *
   * @details This function is called each time the security request timer expires.
   *
   * @param[in] p_context  Pointer used for passing context information from the
   *                       app_start_timer() call to the time-out handler.
   */
  static void sec_req_timeout_handler(void * p_context)
  {
      ret_code_t           ret;
      pm_conn_sec_status_t status;
  
      if (m_cur_conn_handle != BLE_CONN_HANDLE_INVALID)
      {
          ret = pm_conn_sec_status_get(m_cur_conn_handle, &status);
          APP_ERROR_CHECK(ret);
  
          // If the link is still not secured by the peer, initiate security procedure.
          if (!status.encrypted)
          {
              ret = pm_conn_secure(m_cur_conn_handle, false);
              if (ret != NRF_ERROR_INVALID_STATE)
              {
                  APP_ERROR_CHECK(ret);
              }
          }
      }
  }
  
  
  /**@brief Function for setting up GATTC notifications from the Notification Provider.
   *
   * @details This function is called when a successful connection has been established.
   */
  static void apple_notification_setup(void)
  {
      ret_code_t ret;
  
      nrf_delay_ms(100); // Delay because we cannot add a CCCD to close to starting encryption. iOS specific.
  
      ret = ble_ancs_c_notif_source_notif_enable(&m_ancs_c);
      APP_ERROR_CHECK(ret);
  
      ret = ble_ancs_c_data_source_notif_enable(&m_ancs_c);
      APP_ERROR_CHECK(ret);
  
      NRF_LOG_DEBUG("Notifications Enabled.\r\n");
  }
  
  
  /**@brief Function for printing an iOS notification.
   *
   * @param[in] p_notif  Pointer to the iOS notification.
   */
  static void notif_print(ble_ancs_c_evt_notif_t * p_notif)
  {
      NRF_LOG_INFO("\r\nNotification\r\n");
      NRF_LOG_INFO("Event:       %s\r\n", (uint32_t)lit_eventid[p_notif->evt_id]);
      NRF_LOG_INFO("Category ID: %s\r\n", (uint32_t)lit_catid[p_notif->category_id]);
      NRF_LOG_INFO("Category Cnt:%u\r\n", (unsigned int) p_notif->category_count);
      NRF_LOG_INFO("UID:         %u\r\n", (unsigned int) p_notif->notif_uid);
  
      NRF_LOG_INFO("Flags:\r\n");
      if(p_notif->evt_flags.silent == 1)
      {
          NRF_LOG_INFO(" Silent\r\n");
      }
      if(p_notif->evt_flags.important == 1)
      {
          NRF_LOG_INFO(" Important\r\n");
      }
      if(p_notif->evt_flags.pre_existing == 1)
      {
          NRF_LOG_INFO(" Pre-existing\r\n");
      }
      if(p_notif->evt_flags.positive_action == 1)
      {
          NRF_LOG_INFO(" Positive Action\r\n");
      }
      if(p_notif->evt_flags.negative_action == 1)
      {
          NRF_LOG_INFO(" Negative Action\r\n");
      }
  }
  
  
  /**@brief Function for printing iOS notification attribute data.
   *
   * @param[in] p_attr Pointer to an iOS notification attribute.
   */
  static void notif_attr_print(ble_ancs_c_attr_t * p_attr)
  {
      if (p_attr->attr_len != 0)
      {
          NRF_LOG_INFO("%s: %s\r\n", (uint32_t)lit_attrid[p_attr->attr_id], nrf_log_push((char *)p_attr->p_attr_data));
      }
      else if (p_attr->attr_len == 0)
      {
          NRF_LOG_INFO("%s: (N/A)\r\n", (uint32_t)lit_attrid[p_attr->attr_id]);
      }
  }
  
  
  /**@brief Function for printing iOS notification attribute data.
   *
   * @param[in] p_attr Pointer to an iOS App attribute.
   */
  static void app_attr_print(ble_ancs_c_attr_t * p_attr)
  {
      if (p_attr->attr_len != 0)
      {
          NRF_LOG_INFO("%s: %s\r\n", (uint32_t)lit_appid[p_attr->attr_id], (uint32_t)p_attr->p_attr_data);
      }
      else if (p_attr->attr_len == 0)
      {
          NRF_LOG_INFO("%s: (N/A)\r\n", (uint32_t) lit_appid[p_attr->attr_id]);
      }
  }
  
  
  /**@brief Function for printing out errors that originated from the Notification Provider (iOS).
   *
   * @param[in] err_code_np Error code received from NP.
   */
  static void err_code_print(uint16_t err_code_np)
  {
      switch (err_code_np)
      {
          case BLE_ANCS_NP_UNKNOWN_COMMAND:
              NRF_LOG_INFO("Error: Command ID was not recognized by the Notification Provider. \r\n");
              break;
  
          case BLE_ANCS_NP_INVALID_COMMAND:
              NRF_LOG_INFO("Error: Command failed to be parsed on the Notification Provider. \r\n");
              break;
  
          case BLE_ANCS_NP_INVALID_PARAMETER:
              NRF_LOG_INFO("Error: Parameter does not refer to an existing object on the Notification Provider. \r\n");
              break;
  
          case BLE_ANCS_NP_ACTION_FAILED:
              NRF_LOG_INFO("Error: Perform Notification Action Failed on the Notification Provider. \r\n");
              break;
  
          default:
              break;
      }
  }
  /**@brief Function for initializing the timer module.
   */
  static void timers_init(void)
  {
      ret_code_t ret;
  
      ret = app_timer_init();
      APP_ERROR_CHECK(ret);
  
      // Create security request timer.
      ret = app_timer_create(&m_sec_req_timer_id,
                             APP_TIMER_MODE_SINGLE_SHOT,
                             sec_req_timeout_handler);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for handling the Apple Notification Service client.
   *
   * @details This function is called for all events in the Apple Notification client that
   *          are passed to the application.
   *
   * @param[in] p_evt  Event received from the Apple Notification Service client.
   */
  static void on_ancs_c_evt(ble_ancs_c_evt_t * p_evt)
  {
      ret_code_t ret = NRF_SUCCESS;
  
      switch (p_evt->evt_type)
      {
          case BLE_ANCS_C_EVT_DISCOVERY_COMPLETE:
              NRF_LOG_DEBUG("Apple Notification Center Service discovered on the server.\r\n");
              ret = nrf_ble_ancs_c_handles_assign(&m_ancs_c, p_evt->conn_handle, &p_evt->service);
              APP_ERROR_CHECK(ret);
              apple_notification_setup();
              break;
  
          case BLE_ANCS_C_EVT_NOTIF:
              m_notification_latest = p_evt->notif;
              notif_print(&m_notification_latest);
              break;
  
          case BLE_ANCS_C_EVT_NOTIF_ATTRIBUTE:
              m_notif_attr_latest = p_evt->attr;
              notif_attr_print(&m_notif_attr_latest);
              if(p_evt->attr.attr_id == BLE_ANCS_NOTIF_ATTR_ID_APP_IDENTIFIER)
              {
                  m_notif_attr_app_id_latest = p_evt->attr;
              }
              break;
          case BLE_ANCS_C_EVT_DISCOVERY_FAILED:
              NRF_LOG_DEBUG("Apple Notification Center Service not discovered on the server.\r\n");
              break;
  
          case BLE_ANCS_C_EVT_APP_ATTRIBUTE:
              app_attr_print(&p_evt->attr);
              break;
          case BLE_ANCS_C_EVT_NP_ERROR:
              err_code_print(p_evt->err_code_np);
              break;
          default:
              // No implementation needed.
              break;
      }
  }
  
  
  /**@brief Function for initializing GAP connection parameters.
   *
   * @details Use this function to set up all necessary GAP (Generic Access Profile)
   *          parameters of the device. It also sets the permissions and appearance.
   */
  static void gap_params_init(void)
  {
      ret_code_t              ret;
      ble_gap_conn_params_t   gap_conn_params;
      ble_gap_conn_sec_mode_t sec_mode;
  
      BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);
  
      ret = sd_ble_gap_device_name_set(&sec_mode, (const uint8_t *)DEVICE_NAME, strlen(DEVICE_NAME));
      APP_ERROR_CHECK(ret);
  
      memset(&gap_conn_params, 0, sizeof(gap_conn_params));
  
      gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;
      gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
      gap_conn_params.slave_latency     = SLAVE_LATENCY;
      gap_conn_params.conn_sup_timeout  = CONN_SUP_TIMEOUT;
  
      ret = sd_ble_gap_ppcp_set(&gap_conn_params);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for initializing the GATT module.
   */
  static void gatt_init(void)
  {
      ret_code_t ret = nrf_ble_gatt_init(&m_gatt, NULL);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for handling the Apple Notification Service client errors.
   *
   * @param[in] nrf_error  Error code containing information about what went wrong.
   */
  static void apple_notification_error_handler(uint32_t nrf_error)
  {
      APP_ERROR_HANDLER(nrf_error);
  }
  
  
  /**@brief Function for handling a Connection Parameters error.
   *
   * @param[in] nrf_error  Error code containing information about what went wrong.
   */
  static void conn_params_error_handler(uint32_t nrf_error)
  {
      APP_ERROR_HANDLER(nrf_error);
  }
  
  
  /**@brief Function for initializing the Connection Parameters module.
   */
  static void conn_params_init(void)
  {
      ret_code_t             ret;
      ble_conn_params_init_t cp_init;
  
      memset(&cp_init, 0, sizeof(cp_init));
  
      cp_init.p_conn_params                  = NULL;
      cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
      cp_init.next_conn_params_update_delay  = NEXT_CONN_PARAMS_UPDATE_DELAY;
      cp_init.max_conn_params_update_count   = MAX_CONN_PARAMS_UPDATE_COUNT;
      cp_init.start_on_notify_cccd_handle    = BLE_GATT_HANDLE_INVALID;
      cp_init.disconnect_on_fail             = true;
      cp_init.evt_handler                    = NULL;
      cp_init.error_handler                  = conn_params_error_handler;
  
      ret = ble_conn_params_init(&cp_init);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for handling Database Discovery events.
   *
   * @details This function is a callback function to handle events from the database discovery module.
   *          Depending on the UUIDs that are discovered, this function should forward the events
   *          to their respective service instances.
   *
   * @param[in] p_event  Pointer to the database discovery event.
   */
  static void db_disc_handler(ble_db_discovery_evt_t * p_evt)
  {
      ble_ancs_c_on_db_disc_evt(&m_ancs_c, p_evt);
  }
  
  
  /**@brief Function for the Peer Manager initialization.
   */
  static void peer_manager_init(void)
  {
      ble_gap_sec_params_t sec_param;
      ret_code_t           ret;
  
      ret = pm_init();
      APP_ERROR_CHECK(ret);
  
      memset(&sec_param, 0, sizeof(ble_gap_sec_params_t));
  
      // Security parameters to be used for all security procedures.
      sec_param.bond           = SEC_PARAM_BOND;
      sec_param.mitm           = SEC_PARAM_MITM;
      sec_param.lesc           = SEC_PARAM_LESC;
      sec_param.keypress       = SEC_PARAM_KEYPRESS;
      sec_param.io_caps        = SEC_PARAM_IO_CAPABILITIES;
      sec_param.oob            = SEC_PARAM_OOB;
      sec_param.min_key_size   = SEC_PARAM_MIN_KEY_SIZE;
      sec_param.max_key_size   = SEC_PARAM_MAX_KEY_SIZE;
      sec_param.kdist_own.enc  = 1;
      sec_param.kdist_own.id   = 1;
      sec_param.kdist_peer.enc = 1;
      sec_param.kdist_peer.id  = 1;
  
      ret = pm_sec_params_set(&sec_param);
      APP_ERROR_CHECK(ret);
  
      ret = pm_register(pm_evt_handler);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**
   * @brief Delete all data stored for all peers
   */
  static void delete_bonds(void)
  {
      ret_code_t err_code;
  
      NRF_LOG_INFO("Erase bonds!\r\n");
  
      err_code = pm_peers_delete();
      APP_ERROR_CHECK(err_code);
  }
  
  
  /**@brief Function for putting the chip into sleep mode.
   *
   * @note This function will not return.
   */
  static void sleep_mode_enter(void)
  {
      uint32_t ret = bsp_indication_set(BSP_INDICATE_IDLE);
      APP_ERROR_CHECK(ret);
  
      // Prepare wakeup buttons.
      ret = bsp_btn_ble_sleep_mode_prepare();
      APP_ERROR_CHECK(ret);
  
      // Go to system-off mode (this function will not return; wakeup will cause a reset).
      ret = sd_power_system_off();
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for handling advertising events.
   *
   * @details This function is called for advertising events that are passed to the application.
   *
   * @param[in] ble_adv_evt  Advertising event.
   */
  static void on_adv_evt(ble_adv_evt_t ble_adv_evt)
  {
      ret_code_t ret;
  
      switch (ble_adv_evt)
      {
          case BLE_ADV_EVT_FAST:
              NRF_LOG_INFO("Fast advertising\r\n");
              ret = bsp_indication_set(BSP_INDICATE_ADVERTISING);
              APP_ERROR_CHECK(ret);
              break;
  
          case BLE_ADV_EVT_SLOW:
              NRF_LOG_INFO("Slow advertising\r\n");
              ret = bsp_indication_set(BSP_INDICATE_ADVERTISING_SLOW);
              APP_ERROR_CHECK(ret);
              break;
  
          case BLE_ADV_EVT_FAST_WHITELIST:
              NRF_LOG_INFO("Fast advertising with Whitelist\r\n");
              ret = bsp_indication_set(BSP_INDICATE_ADVERTISING_WHITELIST);
              APP_ERROR_CHECK(ret);
              break;
  
          case BLE_ADV_EVT_IDLE:
              sleep_mode_enter();
              break;
  
          case BLE_ADV_EVT_WHITELIST_REQUEST:
          {
              ble_gap_addr_t whitelist_addrs[BLE_GAP_WHITELIST_ADDR_MAX_COUNT];
              ble_gap_irk_t  whitelist_irks[BLE_GAP_WHITELIST_ADDR_MAX_COUNT];
              uint32_t       addr_cnt = BLE_GAP_WHITELIST_ADDR_MAX_COUNT;
              uint32_t       irk_cnt  = BLE_GAP_WHITELIST_ADDR_MAX_COUNT;
  
              ret = pm_whitelist_get(whitelist_addrs, &addr_cnt, whitelist_irks, &irk_cnt);
              APP_ERROR_CHECK(ret);
              NRF_LOG_DEBUG("pm_whitelist_get returns %d addr in whitelist and %d irk whitelist\r\n",
                             addr_cnt,
                             irk_cnt);
  
              // Apply the whitelist.
              ret = ble_advertising_whitelist_reply(whitelist_addrs,
                                                    addr_cnt,
                                                    whitelist_irks,
                                                    irk_cnt);
              APP_ERROR_CHECK(ret);
          }
          break;
  
          default:
              break;
      }
  }
  
  
  /**@brief Function for handling the application's BLE stack events.
   *
   * @param[in] p_ble_evt  Bluetooth stack event.
   */
  static void on_ble_evt(ble_evt_t * p_ble_evt)
  {
      ret_code_t ret = NRF_SUCCESS;
  
      switch (p_ble_evt->header.evt_id)
      {
          case BLE_GAP_EVT_CONNECTED:
              NRF_LOG_INFO("Connected.\r\n");
              ret = bsp_indication_set(BSP_INDICATE_CONNECTED);
              APP_ERROR_CHECK(ret);
  
              m_cur_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
              ret               = app_timer_start(m_sec_req_timer_id, SECURITY_REQUEST_DELAY, NULL);
              APP_ERROR_CHECK(ret);
              break; // BLE_GAP_EVT_CONNECTED
  
          case BLE_GAP_EVT_DISCONNECTED:
              NRF_LOG_INFO("Disconnected.\r\n");
              m_cur_conn_handle = BLE_CONN_HANDLE_INVALID;
              ret               = app_timer_stop(m_sec_req_timer_id);
              APP_ERROR_CHECK(ret);
  
              if (p_ble_evt->evt.gap_evt.conn_handle == m_ancs_c.conn_handle)
              {
                  m_ancs_c.conn_handle = BLE_CONN_HANDLE_INVALID;
              }
              if (m_is_wl_changed)
              {
                  // The whitelist has been modified, update it in the Peer Manager.
                  ret = pm_whitelist_set(m_whitelist_peers, m_whitelist_peer_cnt);
                  APP_ERROR_CHECK(ret);
  
                  ret = pm_device_identities_list_set(m_whitelist_peers, m_whitelist_peer_cnt);
                  if (ret != NRF_ERROR_NOT_SUPPORTED)
                  {
                      APP_ERROR_CHECK(ret);
                  }
  
                  m_is_wl_changed = false;
              }
              break; // BLE_GAP_EVT_DISCONNECTED
  
          case BLE_GATTC_EVT_TIMEOUT:
              // Disconnect on GATT Client timeout event.
              NRF_LOG_DEBUG("GATT Client Timeout.\r\n");
              ret = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
                                          BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
              APP_ERROR_CHECK(ret);
              break; // BLE_GATTC_EVT_TIMEOUT
  
          case BLE_GATTS_EVT_TIMEOUT:
              // Disconnect on GATT Server timeout event.
              NRF_LOG_DEBUG("GATT Server Timeout.\r\n");
              ret = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
                                          BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
              APP_ERROR_CHECK(ret);
              break; // BLE_GATTS_EVT_TIMEOUT
  
          default:
              // No implementation needed.
              break;
      }
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for handling events from the BSP module.
   *
   * @param[in] event  Event generated by button press.
   */
  static void bsp_event_handler(bsp_event_t event)
  {
      ret_code_t ret;
  
      switch (event)
      {
          case BSP_EVENT_SLEEP:
              sleep_mode_enter();
              break;
  
          case BSP_EVENT_DISCONNECT:
              ret = sd_ble_gap_disconnect(m_cur_conn_handle,
                                          BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
              if (ret != NRF_ERROR_INVALID_STATE)
              {
                  APP_ERROR_CHECK(ret);
              }
              break;
  
          case BSP_EVENT_WHITELIST_OFF:
              if (m_ancs_c.conn_handle == BLE_CONN_HANDLE_INVALID)
              {
                  ret = ble_advertising_restart_without_whitelist();
                  if (ret != NRF_ERROR_INVALID_STATE)
                  {
                      APP_ERROR_CHECK(ret);
                  }
              }
              break;
  
          case BSP_EVENT_KEY_0:
              ret = nrf_ble_ancs_c_request_attrs(&m_ancs_c, &m_notification_latest);
              APP_ERROR_CHECK(ret);
              break;
  
          case BSP_EVENT_KEY_1:
              if(m_notif_attr_app_id_latest.attr_id == BLE_ANCS_NOTIF_ATTR_ID_APP_IDENTIFIER
                  && m_notif_attr_app_id_latest.attr_len != 0)
              {
                  NRF_LOG_INFO("Request for %s: \r\n", (uint32_t)m_notif_attr_app_id_latest.p_attr_data);
                  ret = nrf_ble_ancs_c_app_attr_request(&m_ancs_c,
                                                        m_notif_attr_app_id_latest.p_attr_data,
                                                        m_notif_attr_app_id_latest.attr_len);
                  APP_ERROR_CHECK(ret);
              }
              break;
  
          case BSP_EVENT_KEY_2:
              if(m_notification_latest.evt_flags.positive_action == true)
              {
                  NRF_LOG_INFO("Performing Positive Action.\r\n");
                  ret = nrf_ancs_perform_notif_action(&m_ancs_c,
                                                      m_notification_latest.notif_uid,
                                                      ACTION_ID_POSITIVE);
                  APP_ERROR_CHECK(ret);
              }
              break;
  
          case BSP_EVENT_KEY_3:
              if(m_notification_latest.evt_flags.negative_action == true)
              {
                  NRF_LOG_INFO("Performing Negative Action.\r\n");
                  ret = nrf_ancs_perform_notif_action(&m_ancs_c,
                                                      m_notification_latest.notif_uid,
                                                      ACTION_ID_NEGATIVE);
                  APP_ERROR_CHECK(ret);
              }
              break;
  
          default:
              break;
      }
  }
  
  
  /**@brief Function for dispatching a BLE stack event to all modules with a BLE stack event handler.
   *
   * @details This function is called from the BLE Stack event interrupt handler after a BLE stack
   *          event has been received.
   *
   * @param[in] p_ble_evt  Bluetooth stack event.
   */
  static void ble_evt_dispatch(ble_evt_t * p_ble_evt)
  {
      /** The Connection state module has to be fed BLE events in order to function correctly
       * Remember to call ble_conn_state_on_ble_evt before calling any ble_conns_state_* functions. */
      ble_conn_state_on_ble_evt(p_ble_evt);
      pm_on_ble_evt(p_ble_evt);
      ble_db_discovery_on_ble_evt(&m_ble_db_discovery, p_ble_evt);
      ble_conn_params_on_ble_evt(p_ble_evt);
      ble_ancs_c_on_ble_evt(&m_ancs_c, p_ble_evt);
      bsp_btn_ble_on_ble_evt(p_ble_evt);
      on_ble_evt(p_ble_evt);
      ble_advertising_on_ble_evt(p_ble_evt);
      nrf_ble_gatt_on_ble_evt(&m_gatt, p_ble_evt);
  }
  
  
  /**@brief Function for dispatching a system event to interested modules.
   *
   * @details This function is called from the system event interrupt handler after a system
   *          event has been received.
   *
   * @param[in] sys_evt  System stack event.
   */
  static void sys_evt_dispatch(uint32_t sys_evt)
  {
      // Dispatch the system event to the fstorage module, where it will be
      // dispatched to the Flash Data Storage (FDS) module.
      fs_sys_event_handler(sys_evt);
  
      // Dispatch to the Advertising module last, since it will check if there are any
      // pending flash operations in fstorage. Let fstorage process system events first,
      // so that it can report correctly to the Advertising module.
      ble_advertising_on_sys_evt(sys_evt);
  }
  
  
  /**@brief Function for initializing the BLE stack.
   *
   * @details Initializes the SoftDevice and the BLE event interrupt.
   */
  static void ble_stack_init(void)
  {
      uint32_t err_code;
  
      nrf_clock_lf_cfg_t clock_lf_cfg = NRF_CLOCK_LFCLKSRC;
  
      // Initialize the SoftDevice handler module.
      SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);
  
      // Fetch the start address of the application RAM.
      uint32_t ram_start = 0;
      err_code = softdevice_app_ram_start_get(&ram_start);
      APP_ERROR_CHECK(err_code);
  
      // Overwrite some of the default configurations for the BLE stack.
      ble_cfg_t ble_cfg;
  
      // Configure the maximum number of connections.
      memset(&ble_cfg, 0, sizeof(ble_cfg));
      ble_cfg.gap_cfg.role_count_cfg.periph_role_count  = BLE_GAP_ROLE_COUNT_PERIPH_DEFAULT;
      ble_cfg.gap_cfg.role_count_cfg.central_role_count = 0;
      ble_cfg.gap_cfg.role_count_cfg.central_sec_count  = 0;
      err_code = sd_ble_cfg_set(BLE_GAP_CFG_ROLE_COUNT, &ble_cfg, ram_start);
      APP_ERROR_CHECK(err_code);
  
      // Enable BLE stack.
      err_code = softdevice_enable(&ram_start);
      APP_ERROR_CHECK(err_code);
  
      // Register with the SoftDevice handler module for BLE events.
      err_code = softdevice_ble_evt_handler_set(ble_evt_dispatch);
      APP_ERROR_CHECK(err_code);
  
      // Register with the SoftDevice handler module for BLE events.
      err_code = softdevice_sys_evt_handler_set(sys_evt_dispatch);
      APP_ERROR_CHECK(err_code);
  }
  
  
  /**@brief Function for initializing the Apple Notification Center Service.
   */
  static void services_init(void)
  {
      ble_ancs_c_init_t ancs_init_obj;
      ret_code_t        ret;
  
      memset(&ancs_init_obj, 0, sizeof(ancs_init_obj));
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_APP_IDENTIFIER,
                                    m_attr_appid,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_app_attr_add(&m_ancs_c,
                                        BLE_ANCS_APP_ATTR_ID_DISPLAY_NAME,
                                        m_attr_disp_name,
                                        sizeof(m_attr_disp_name));
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_TITLE,
                                    m_attr_title,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_MESSAGE,
                                    m_attr_message,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_SUBTITLE,
                                    m_attr_subtitle,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_MESSAGE_SIZE,
                                    m_attr_message_size,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_DATE,
                                    m_attr_date,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_POSITIVE_ACTION_LABEL,
                                    m_attr_posaction,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ret = nrf_ble_ancs_c_attr_add(&m_ancs_c,
                                    BLE_ANCS_NOTIF_ATTR_ID_NEGATIVE_ACTION_LABEL,
                                    m_attr_negaction,
                                    ATTR_DATA_SIZE);
      APP_ERROR_CHECK(ret);
  
      ancs_init_obj.evt_handler   = on_ancs_c_evt;
      ancs_init_obj.error_handler = apple_notification_error_handler;
  
      ret = ble_ancs_c_init(&m_ancs_c, &ancs_init_obj);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for initializing the advertising functionality.
   */
  static void advertising_init(void)
  {
      ret_code_t             ret;
      ble_advdata_t          advdata;
      ble_adv_modes_config_t options;
  
      static ble_uuid_t m_adv_uuids[1]; /**< Universally unique service identifiers. */
  
      m_adv_uuids[0].uuid = ANCS_UUID_SERVICE;
      m_adv_uuids[0].type = m_ancs_c.service.service.uuid.type;
  
      // Build and set advertising data
      memset(&advdata, 0, sizeof(advdata));
  
      advdata.name_type                = BLE_ADVDATA_FULL_NAME;
      advdata.include_appearance       = true;
      advdata.flags                    = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;
      advdata.uuids_complete.uuid_cnt  = 0;
      advdata.uuids_complete.p_uuids   = NULL;
      advdata.uuids_solicited.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
      advdata.uuids_solicited.p_uuids  = m_adv_uuids;
  
      memset(&options, 0, sizeof(options));
      options.ble_adv_whitelist_enabled = true;
      options.ble_adv_fast_enabled      = true;
      options.ble_adv_fast_interval     = APP_ADV_FAST_INTERVAL;
      options.ble_adv_fast_timeout      = APP_ADV_FAST_TIMEOUT;
      options.ble_adv_slow_enabled      = true;
      options.ble_adv_slow_interval     = APP_ADV_SLOW_INTERVAL;
      options.ble_adv_slow_timeout      = APP_ADV_SLOW_TIMEOUT;
  
      ret = ble_advertising_init(&advdata, NULL, &options, on_adv_evt, NULL);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for initializing buttons and LEDs.
   *
   * @param[out] p_erase_bonds  True if the clear bonds button was pressed to wake the application up.
   */
  static void buttons_leds_init(bool * p_erase_bonds)
  {
      uint32_t ret;
      bsp_event_t startup_event;
  
      ret = bsp_init(BSP_INIT_LED | BSP_INIT_BUTTONS, bsp_event_handler);
      APP_ERROR_CHECK(ret);
  
      ret = bsp_btn_ble_init(NULL, &startup_event);
      APP_ERROR_CHECK(ret);
  
      *p_erase_bonds = (startup_event == BSP_EVENT_CLEAR_BONDING_DATA);
  }
  
  
  /**@brief Function for initializing the Event Scheduler.
   */
  static void scheduler_init(void)
  {
      APP_SCHED_INIT(SCHED_MAX_EVENT_DATA_SIZE, SCHED_QUEUE_SIZE);
  }
  
  
  /**@brief Function for initializing the database discovery module.
   */
  static void db_discovery_init(void)
  {
      ret_code_t ret = ble_db_discovery_init(db_disc_handler);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for initializing the nrf log module.
   */
  static void log_init(void)
  {
      ret_code_t ret = NRF_LOG_INIT(NULL);
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for the Power manager.
   */
  static void power_manage(void)
  {
      ret_code_t ret = sd_app_evt_wait();
      APP_ERROR_CHECK(ret);
  }
  
  
  /**@brief Function for application main entry.
   */
  int main(void)
  {
      bool erase_bonds;
  
      // Initialize.
      log_init();
      timers_init();
      buttons_leds_init(&erase_bonds);
      scheduler_init();
      ble_stack_init();
      gap_params_init();
      gatt_init();
      db_discovery_init();
      services_init();
      advertising_init();
      conn_params_init();
      peer_manager_init();
  
      // Start execution.
      NRF_LOG_INFO("Apple Notification Center Service client example started.\r\n");
      advertising_start(erase_bonds);
  
      // Enter main loop.
      for (;;)
      {
          app_sched_execute();
          if (NRF_LOG_PROCESS() == false)
          {
              power_manage();
          }
      }
  
  }
  
  
  /**
   * @}
   */
  
  