main.c

/**
 * Copyright (c) 2015 - 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.
 * 
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 * 
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */
/**
 * @brief Blinky Sample Application main file.
 *
 * This file contains the source code for a sample server application using the LED Button service.
 */

#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "app_error.h"
#include "ble.h"
#include "ble_hci.h"
#include "ble_srv_common.h"
#include "ble_advdata.h"
#include "ble_conn_params.h"
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "boards.h"
#include "app_timer.h"
#include "app_button.h"
#include "ble_lbs.h"
#include "nrf_ble_gatt.h"
#include "app_display.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"


#define APP_FEATURE_NOT_SUPPORTED       BLE_GATT_STATUS_ATTERR_APP_BEGIN + 2    /**< Reply when unsupported features are requested. */

#define ADVERTISING_LED                 BSP_BOARD_LED_0                         /**< Is on when device is advertising. */
#define CONNECTED_LED                   BSP_BOARD_LED_1                         /**< Is on when device has connected. */
#define LEDBUTTON_LED                   BSP_BOARD_LED_2                         /**< LED to be toggled with the help of the LED Button Service. */

#define PHY_BUTTON                      BSP_BUTTON_0
#define TX_POWER_BUTTON                 BSP_BUTTON_1
#define APP_STATE_BUTTON                BSP_BUTTON_2
#define LEDBUTTON_BUTTON                BSP_BUTTON_3                            /**< Button that will trigger the notification event with the LED Button Service */

#define DEVICE_NAME                     "NT:LR Blinky"                          /**< Name of device. Will be included in the advertising data. */

#define APP_BLE_OBSERVER_PRIO           1                                       /**< Application's BLE observer priority. You shouldn't need to modify this value. */
#define APP_BLE_CONN_CFG_TAG            1                                       /**< A tag identifying the SoftDevice BLE configuration. */

#define APP_ADV_INTERVAL                300                                      /**< The advertising interval (in units of 0.625 ms; this value corresponds to 40 ms). */
#define APP_ADV_DURATION                BLE_GAP_ADV_TIMEOUT_GENERAL_UNLIMITED   /**< The advertising time-out (in units of seconds). When set to 0, we will never time out. */
#define RESTART_ADVERTISING_TIMEOUT_MS  2000

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(100, UNIT_1_25_MS)        /**< Minimum acceptable connection interval (0.5 seconds). */
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(200, 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(20000)                  /**< Time from initiating event (connect or start of notification) to first time sd_ble_gap_conn_param_update is called (15 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY   APP_TIMER_TICKS(5000)                   /**< Time between each call to sd_ble_gap_conn_param_update after the first call (5 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT    3                                       /**< Number of attempts before giving up the connection parameter negotiation. */

#define BUTTON_DETECTION_DELAY          APP_TIMER_TICKS(50)                     /**< Delay from a GPIOTE event until a button is reported as pushed (in number of timer ticks). */

#define DEAD_BEEF                       0xDEADBEEF                              /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */


BLE_LBS_DEF(m_lbs);                                                             /**< LED Button Service instance. */
BLE_LBS_DEF(m_lbs2);
BLE_LBS_DEF(m_lbs3);
ble_lbs_t *m_lbs_list[] = {&m_lbs, &m_lbs2, &m_lbs3};
static uint32_t m_lbs_links_active = 0;

NRF_BLE_GATT_DEF(m_gatt);                                                       /**< GATT module instance. */

APP_TIMER_DEF(m_restart_advertising_timer_id);

static uint16_t m_conn_handle[3] = {BLE_CONN_HANDLE_INVALID, BLE_CONN_HANDLE_INVALID, BLE_CONN_HANDLE_INVALID};  /**< Handle of the current connections. */

static uint8_t m_adv_handle = BLE_GAP_ADV_SET_HANDLE_NOT_SET;                   /**< Advertising handle used to identify an advertising set. */
static uint8_t m_enc_advdata[BLE_GAP_ADV_SET_DATA_SIZE_MAX];                    /**< Buffer for storing an encoded advertising set. */
static uint8_t m_enc_scan_response_data[BLE_GAP_ADV_SET_DATA_SIZE_MAX];         /**< Buffer for storing an encoded scan data. */

/**@brief Struct that contains pointers to the encoded advertising data. */
static ble_gap_adv_data_t m_adv_data =
{
    .adv_data =
    {
        .p_data = m_enc_advdata,
        .len    = BLE_GAP_ADV_SET_DATA_SIZE_MAX
    },
    .scan_rsp_data =
    {
        .p_data = m_enc_scan_response_data,
        .len    = BLE_GAP_ADV_SET_DATA_SIZE_MAX

    }
};

static void display_update(void);
static void advertising_start(void);

app_display_content_t m_application_state = {0};                                   /**< Struct containing the dynamic content of the display */

/**@brief Function for assert macro callback.
 *
 * @details This function will be called in case of an assert in the SoftDevice.
 *
 * @warning This handler is an example only and does not fit a final product. You need to analyze
 *          how your product is supposed to react in case of Assert.
 * @warning On assert from the SoftDevice, the system can only recover on reset.
 *
 * @param[in] line_num    Line number of the failing ASSERT call.
 * @param[in] p_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 Function for the LEDs initialization.
 *
 * @details Initializes all LEDs used by the application.
 */
static void leds_init(void)
{
    bsp_board_init(BSP_INIT_LEDS);
}


static void restart_advertising_callback(void *p)
{
    advertising_start();
}


/**@brief Function for the Timer initialization.
 *
 * @details Initializes the timer module.
 */
static void timers_init(void)
{
    // Initialize timer module, making it use the scheduler
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);
    
    err_code = app_timer_create(&m_restart_advertising_timer_id, APP_TIMER_MODE_SINGLE_SHOT, restart_advertising_callback);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for the GAP initialization.
 *
 * @details This function sets up all the necessary GAP (Generic Access Profile) parameters of the
 *          device including the device name, appearance, and the preferred connection parameters.
 */
static void gap_params_init(void)
{
    ret_code_t              err_code;
    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);

    err_code = sd_ble_gap_device_name_set(&sec_mode,
                                          (const uint8_t *)DEVICE_NAME,
                                          strlen(DEVICE_NAME));
    APP_ERROR_CHECK(err_code);

    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;

    err_code = sd_ble_gap_ppcp_set(&gap_conn_params);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for initializing the GATT module.
 */
static void gatt_init(void)
{
    ret_code_t err_code = nrf_ble_gatt_init(&m_gatt, NULL);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for initializing the Advertising functionality.
 *
 * @details Encodes the required advertising data and passes it to the stack.
 *          Also builds a structure to be passed to the stack when starting advertising.
 */
static void advertising_init(void)
{
    ret_code_t    err_code;
    ble_advdata_t advdata;
    ble_advdata_t srdata;

    //ble_uuid_t adv_uuids[] = {{LBS_UUID_SERVICE, m_lbs.uuid_type}};

    // Build and set advertising data.
    memset(&advdata, 0, sizeof(advdata));

    advdata.name_type          = BLE_ADVDATA_FULL_NAME;
    advdata.include_appearance = false;
    advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;

    memset(&srdata, 0, sizeof(srdata));

    err_code = ble_advdata_encode(&advdata, m_adv_data.adv_data.p_data, &m_adv_data.adv_data.len);
    APP_ERROR_CHECK(err_code);

    err_code = ble_advdata_encode(&srdata, m_adv_data.scan_rsp_data.p_data, &m_adv_data.scan_rsp_data.len);
    APP_ERROR_CHECK(err_code);

    ble_gap_adv_params_t adv_params;

    // Set advertising parameters.
    memset(&adv_params, 0, sizeof(adv_params));

    if(m_application_state.phy == APP_PHY_CODED || m_application_state.phy == APP_PHY_MULTI)
    {
        adv_params.primary_phy     = BLE_GAP_PHY_CODED;
        adv_params.secondary_phy   = BLE_GAP_PHY_CODED;
        adv_params.properties.type = BLE_GAP_ADV_TYPE_EXTENDED_CONNECTABLE_NONSCANNABLE_UNDIRECTED;
    }
    else
    {
        adv_params.primary_phy     = BLE_GAP_PHY_1MBPS;
        adv_params.secondary_phy   = BLE_GAP_PHY_1MBPS;
        adv_params.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED;
    }
    adv_params.duration        = APP_ADV_DURATION;
    adv_params.p_peer_addr     = NULL;
    adv_params.filter_policy   = BLE_GAP_ADV_FP_ANY;
    adv_params.interval        = APP_ADV_INTERVAL;

    err_code = sd_ble_gap_adv_set_configure(&m_adv_handle, &m_adv_data, &adv_params);
    APP_ERROR_CHECK(err_code);
    
    err_code = sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_ADV, m_adv_handle, m_application_state.tx_power * 4);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling write events to the LED characteristic.
 *
 * @param[in] p_lbs     Instance of LED Button Service to which the write applies.
 * @param[in] led_state Written/desired state of the LED.
 */
static void led_write_handler(uint16_t conn_handle, ble_lbs_t * p_lbs, uint8_t led_state)
{
    if (led_state)
    {
        bsp_board_led_on(LEDBUTTON_LED);
        NRF_LOG_INFO("Received LED ON!");
        m_application_state.led_on = true;
    }
    else
    {
        bsp_board_led_off(LEDBUTTON_LED);
        NRF_LOG_INFO("Received LED OFF!");
        m_application_state.led_on = false;
    }
    display_update();
}


/**@brief Function for initializing services that will be used by the application.
 */
static void services_init(void)
{
    ret_code_t     err_code;
    ble_lbs_init_t init;

    init.led_write_handler = led_write_handler;

    err_code = ble_lbs_init(&m_lbs, &init);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling the Connection Parameters Module.
 *
 * @details This function will be called for all events in the Connection Parameters Module that
 *          are passed to the application.
 *
 * @note All this function does is to disconnect. This could have been done by simply
 *       setting the disconnect_on_fail config parameter, but instead we use the event
 *       handler mechanism to demonstrate its use.
 *
 * @param[in] p_evt  Event received from the Connection Parameters Module.
 */
static void on_conn_params_evt(ble_conn_params_evt_t * p_evt)
{
    ret_code_t err_code;

    if (p_evt->evt_type == BLE_CONN_PARAMS_EVT_FAILED)
    {
        err_code = sd_ble_gap_disconnect(m_conn_handle[0], BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
        APP_ERROR_CHECK(err_code);
    }
}


/**@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             err_code;
    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             = false;
    cp_init.evt_handler                    = on_conn_params_evt;
    cp_init.error_handler                  = conn_params_error_handler;

    err_code = ble_conn_params_init(&cp_init);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for starting advertising.
 */
static void advertising_start(void)
{
    ret_code_t err_code;
    err_code = sd_ble_gap_adv_start(m_adv_handle, APP_BLE_CONN_CFG_TAG);
    if(err_code == NRF_SUCCESS)
    {
        bsp_board_led_on(ADVERTISING_LED);
    
        m_application_state.app_state = APP_STATE_ADVERTISING;
        display_update();
    }
    else
    {
        APP_ERROR_CHECK(err_code);
    }
}


static void ble_go_to_idle(void)
{
    ret_code_t err_code;
    switch(m_application_state.app_state)
    {
        case APP_STATE_ADVERTISING:
            err_code = sd_ble_gap_adv_stop(m_adv_handle);
            APP_ERROR_CHECK(err_code);
            break;
            
        case APP_STATE_CONNECTED:
            for(int i = 0; i < (m_application_state.phy == APP_PHY_MULTI ? 3 : 1); i++)
            {
                if(m_conn_handle[i] != BLE_CONN_HANDLE_INVALID)
                {
                    err_code = sd_ble_gap_disconnect(m_conn_handle[i], BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
                    APP_ERROR_CHECK(err_code);
                }
            }
            break;
            
        case APP_STATE_DISCONNECTED:
            err_code = app_timer_stop(m_restart_advertising_timer_id);
            APP_ERROR_CHECK(err_code);
            break;
    }
    m_application_state.app_state = APP_STATE_IDLE;
    display_update();
}


static void request_phy(uint16_t c_handle, uint8_t phy)
{
    ble_gap_phys_t phy_req;
    phy_req.tx_phys = phy;
    phy_req.rx_phys = phy;
    sd_ble_gap_phy_update(c_handle, &phy_req);
}


/**@brief Function for handling BLE events.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 * @param[in]   p_context   Unused.
 */
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
    ret_code_t err_code;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            NRF_LOG_INFO("Connected: %i", p_ble_evt->evt.gap_evt.conn_handle);
            bsp_board_led_on(CONNECTED_LED);
            bsp_board_led_off(ADVERTISING_LED);
            m_conn_handle[p_ble_evt->evt.gap_evt.conn_handle] = p_ble_evt->evt.gap_evt.conn_handle;
            
            err_code = sd_ble_gap_rssi_start(m_conn_handle[p_ble_evt->evt.gap_evt.conn_handle], 1, 2);
            APP_ERROR_CHECK(err_code);

            m_lbs_links_active++;

            if(m_application_state.phy == APP_PHY_2M)
            {
                request_phy(0, BLE_GAP_PHY_2MBPS);
            }
            else if(m_application_state.phy == APP_PHY_MULTI)
            {
                m_application_state.trip_phy_connected[p_ble_evt->evt.gap_evt.conn_handle] = true;
                switch(p_ble_evt->evt.gap_evt.conn_handle)
                {
                    case 1:
                        request_phy(1, BLE_GAP_PHY_1MBPS);
                        break;
                    case 2:
                        request_phy(2, BLE_GAP_PHY_2MBPS);
                        break;
                    default:
                        break;
                }
                if(m_lbs_links_active < 3)
                {
                    //advertising_start();
                    // Start advertising "silently", without changing application state from connected
                    err_code = sd_ble_gap_adv_start(m_adv_handle, APP_BLE_CONN_CFG_TAG);
                    if(err_code == NRF_SUCCESS)
                    {
                        bsp_board_led_on(ADVERTISING_LED);
                    }
                }
            }
            
            m_application_state.app_state = APP_STATE_CONNECTED;
            display_update();
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            NRF_LOG_INFO("Disconnected: H-%i, Rsn-%i", p_ble_evt->evt.gap_evt.conn_handle, p_ble_evt->evt.gap_evt.params.disconnected.reason);
            bsp_board_led_off(CONNECTED_LED);
            m_conn_handle[p_ble_evt->evt.gap_evt.conn_handle] = BLE_CONN_HANDLE_INVALID;
            m_application_state.rssi[p_ble_evt->evt.gap_evt.conn_handle] = 0;

            if(m_application_state.phy == APP_PHY_MULTI)
            {
                m_application_state.trip_phy_connected[p_ble_evt->evt.gap_evt.conn_handle] = false;
                if(m_application_state.app_state == APP_STATE_CONNECTED)
                {
                  switch(m_lbs_links_active)
                  {
                      case 3:
                          //advertising_start();
                          // Start advertising "silently", without changing application state from connected
                          err_code = sd_ble_gap_adv_start(m_adv_handle, APP_BLE_CONN_CFG_TAG);
                          if(err_code == NRF_SUCCESS)
                          {
                              bsp_board_led_on(ADVERTISING_LED);
                          }
                          break;
                      case 1:
                          m_application_state.app_state = APP_STATE_ADVERTISING;
                          break;
                  }
                }
            }
            else if(m_application_state.app_state == APP_STATE_CONNECTED)
            {
                m_application_state.app_state = APP_STATE_DISCONNECTED;
            
                err_code = app_timer_start(m_restart_advertising_timer_id, APP_TIMER_TICKS(RESTART_ADVERTISING_TIMEOUT_MS), 0);
                APP_ERROR_CHECK(err_code);
            }

            display_update();

            m_lbs_links_active--;
            break;

        case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
            // Pairing not supported
            err_code = sd_ble_gap_sec_params_reply(m_conn_handle[p_ble_evt->evt.gap_evt.conn_handle],
                                                   BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP,
                                                   NULL,
                                                   NULL);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_SYS_ATTR_MISSING:
            // No system attributes have been stored.
            err_code = sd_ble_gatts_sys_attr_set(m_conn_handle[0], NULL, 0, 0);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTC_EVT_TIMEOUT:
            // Disconnect on GATT Client timeout event.
            NRF_LOG_DEBUG("GATT Client Timeout.");
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_TIMEOUT:
            // Disconnect on GATT Server timeout event.
            NRF_LOG_DEBUG("GATT Server Timeout.");
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_EVT_USER_MEM_REQUEST:
            err_code = sd_ble_user_mem_reply(p_ble_evt->evt.gattc_evt.conn_handle, NULL);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
        {
            ble_gatts_evt_rw_authorize_request_t  req;
            ble_gatts_rw_authorize_reply_params_t auth_reply;

            req = p_ble_evt->evt.gatts_evt.params.authorize_request;

            if (req.type != BLE_GATTS_AUTHORIZE_TYPE_INVALID)
            {
                if ((req.request.write.op == BLE_GATTS_OP_PREP_WRITE_REQ)     ||
                    (req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_NOW) ||
                    (req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL))
                {
                    if (req.type == BLE_GATTS_AUTHORIZE_TYPE_WRITE)
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
                    }
                    else
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_READ;
                    }
                    auth_reply.params.write.gatt_status = APP_FEATURE_NOT_SUPPORTED;
                    err_code = sd_ble_gatts_rw_authorize_reply(p_ble_evt->evt.gatts_evt.conn_handle,
                                                               &auth_reply);
                    APP_ERROR_CHECK(err_code);
                }
            }
        } break; // BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST
        
        case BLE_GAP_EVT_RSSI_CHANGED:
            m_application_state.rssi[p_ble_evt->evt.gap_evt.conn_handle] = p_ble_evt->evt.gap_evt.params.rssi_changed.rssi;
            display_update();
            break;
            
        default:
            // No implementation needed.
            break;
    }
}


/**@brief Function for initializing the BLE stack.
 *
 * @details Initializes the SoftDevice and the BLE event interrupt.
 */
static void ble_stack_init(void)
{
    ret_code_t err_code;

    err_code = nrf_sdh_enable_request();
    APP_ERROR_CHECK(err_code);

    // Configure the BLE stack using the default settings.
    // Fetch the start address of the application RAM.
    uint32_t ram_start = 0;
    err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
    APP_ERROR_CHECK(err_code);

    // Enable BLE stack.
    err_code = nrf_sdh_ble_enable(&ram_start);
    APP_ERROR_CHECK(err_code);

    // Register a handler for BLE events.
    NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
}


/**@brief Function for handling events from the button handler module.
 *
 * @param[in] pin_no        The pin that the event applies to.
 * @param[in] button_action The button action (press/release).
 */
static void button_event_handler(uint8_t pin_no, uint8_t button_action)
{
    ret_code_t err_code;
    ble_gap_phys_t phys;
    
    switch (pin_no)
    {
        case PHY_BUTTON:
            if(button_action == APP_BUTTON_PUSH && m_application_state.app_state == APP_STATE_IDLE)
            {
                m_application_state.phy = (m_application_state.phy + 1) % APP_PHY_LIST_END;
                advertising_init();
                display_update();
            }
            break;
        
        case TX_POWER_BUTTON:
            if(button_action == APP_BUTTON_PUSH)
            {
                m_application_state.tx_power = (m_application_state.tx_power + 1) % 3;
                int8_t tx_power = (int8_t)(m_application_state.tx_power * 4);
                if(m_application_state.app_state == APP_STATE_CONNECTED)
                {
                    err_code = sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_CONN, m_conn_handle[0], tx_power);
                    APP_ERROR_CHECK(err_code);
                }
                else
                {
                    err_code = sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_ADV, m_adv_handle, tx_power);
                    APP_ERROR_CHECK(err_code);
                }   
                display_update();
            }
            break;
        
        case APP_STATE_BUTTON:
            if(button_action == APP_BUTTON_PUSH)
            {
                if(m_application_state.app_state == APP_STATE_IDLE)
                {
                    advertising_start();
                }
                else
                {
                    ble_go_to_idle();
                }
            }
            break;
        
        case LEDBUTTON_BUTTON:
            NRF_LOG_INFO("Send button state change.");
            err_code = ble_lbs_on_button_change(m_conn_handle[0], &m_lbs, button_action);
            if (err_code != NRF_SUCCESS &&
                err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
                err_code != NRF_ERROR_INVALID_STATE &&
                err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
            {
                APP_ERROR_CHECK(err_code);
            }
            m_application_state.button_pressed = button_action;
            display_update();
            break;

        default:
            APP_ERROR_HANDLER(pin_no);
            break;
    }
}


/**@brief Function for initializing the button handler module.
 */
static void buttons_init(void)
{
    ret_code_t err_code;

    //The array must be static because a pointer to it will be saved in the button handler module.
    static app_button_cfg_t buttons[] =
    {
        {PHY_BUTTON,       false, BUTTON_PULL, button_event_handler},
        {TX_POWER_BUTTON,  false, BUTTON_PULL, button_event_handler},
        {APP_STATE_BUTTON, false, BUTTON_PULL, button_event_handler},
        {LEDBUTTON_BUTTON, false, BUTTON_PULL, button_event_handler}
    };

    err_code = app_button_init(buttons, sizeof(buttons) / sizeof(buttons[0]),
                               BUTTON_DETECTION_DELAY);
    APP_ERROR_CHECK(err_code);
}


static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(NULL);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();
}

static void display_update()
{
    static bool first_update = true;
    if(first_update)
    {
        m_application_state.main_title = "Blinky Long Range";
        app_display_create_main_screen(&m_application_state);
        first_update = false;
    }
    else
    {
       app_display_update_main_screen(&m_application_state);
    }
    app_display_update();
}


/**@brief Function for the Power Manager.
 */
static void power_manage(void)
{
    ret_code_t err_code = sd_app_evt_wait();
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for application main entry.
 */
int main(void)
{
    ret_code_t err_code;
    
    // Initialize.
    leds_init();
    timers_init();

    log_init();
    buttons_init();
    ble_stack_init();
    gap_params_init();
    services_init();
    advertising_init();
    gatt_init();
    conn_params_init();

    // Start execution.
    NRF_LOG_INFO("Blinky example started.");
    
    app_display_init(&m_application_state);
    display_update();

    err_code = app_button_enable();
    APP_ERROR_CHECK(err_code);
    
    // Enter main loop.
    for (;;)
    {
        if (NRF_LOG_PROCESS() == false)
        {
            power_manage();
        }
    }
}


/**
 * @}
 */