Bluetooth-LE-Audio-Auracast-Transmitter/test/gatt_server/main/gatts_demo.c

/*
 * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Unlicense OR CC0-1.0
 */

/****************************************************************************
*
* This demo showcases BLE GATT server. It can send adv data, be connected by client.
* Run the gatt_client demo, the client demo will automatically connect to the gatt_server demo.
* Client demo will enable gatt_server's notify after connection. The two devices will then exchange
* data.
*
****************************************************************************/


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "esp_bt.h"

#include "esp_gap_ble_api.h"
#include "esp_gatts_api.h"
#include "esp_bt_defs.h"
#include "esp_bt_main.h"
#include "esp_bt_device.h"
#include "esp_gatt_common_api.h"

#include "sdkconfig.h"

#define GATTS_TAG "GATTS_DEMO"

///Declare the static function
static void gatts_profile_a_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);
static void gatts_profile_b_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);

#define GATTS_SERVICE_UUID_TEST_A   0x00FF
#define GATTS_CHAR_UUID_TEST_A      0xFF01
#define GATTS_DESCR_UUID_TEST_A     0x3333
#define GATTS_NUM_HANDLE_TEST_A     4

#define GATTS_SERVICE_UUID_TEST_B   0x00EE
#define GATTS_CHAR_UUID_TEST_B      0xEE01
#define GATTS_DESCR_UUID_TEST_B     0x2222
#define GATTS_NUM_HANDLE_TEST_B     4

static char test_device_name[ESP_BLE_ADV_NAME_LEN_MAX] = "ESP_GATTS_DEMO";

#define TEST_MANUFACTURER_DATA_LEN  17

#define GATTS_DEMO_CHAR_VAL_LEN_MAX 0x40

#define PREPARE_BUF_MAX_SIZE 1024

static uint8_t char1_str[] = {0x11,0x22,0x33};

static uint16_t descr_value = 0x0;
/**
 * Current MTU size for the active connection.
 *
 * This simplified implementation assumes a single connection.
 * For multi-connection scenarios, the MTU should be stored per connection ID.
 */
static uint16_t local_mtu = 23;

static uint8_t char_value_read[CONFIG_EXAMPLE_CHAR_READ_DATA_LEN] = {0xDE,0xED,0xBE,0xEF};


static esp_gatt_char_prop_t a_property = 0;
static esp_gatt_char_prop_t b_property = 0;

static esp_attr_value_t gatts_demo_char1_val =
{
    .attr_max_len = GATTS_DEMO_CHAR_VAL_LEN_MAX,
    .attr_len     = sizeof(char1_str),
    .attr_value   = char1_str,
};

static uint8_t adv_config_done = 0;
#define adv_config_flag      (1 << 0)
#define scan_rsp_config_flag (1 << 1)

#ifdef CONFIG_EXAMPLE_SET_RAW_ADV_DATA
static uint8_t raw_adv_data[] = {
    /* Flags */
    0x02, ESP_BLE_AD_TYPE_FLAG, 0x06,               // Length 2, Data Type ESP_BLE_AD_TYPE_FLAG, Data 1 (LE General Discoverable Mode, BR/EDR Not Supported)
    /* TX Power Level */
    0x02, ESP_BLE_AD_TYPE_TX_PWR, 0xEB,             // Length 2, Data Type ESP_BLE_AD_TYPE_TX_PWR, Data 2 (-21)
    /* Complete 16-bit Service UUIDs */
    0x03, ESP_BLE_AD_TYPE_16SRV_CMPL, 0xAB, 0xCD    // Length 3, Data Type ESP_BLE_AD_TYPE_16SRV_CMPL, Data 3 (UUID)
};

static uint8_t raw_scan_rsp_data[] = {
    /* Complete Local Name */
    0x0F, ESP_BLE_AD_TYPE_NAME_CMPL, 'E', 'S', 'P', '_', 'G', 'A', 'T', 'T', 'S', '_', 'D', 'E', 'M', 'O'   // Length 15, Data Type ESP_BLE_AD_TYPE_NAME_CMPL, Data (ESP_GATTS_DEMO)
};
#else

static uint8_t adv_service_uuid128[32] = {
    /* LSB <--------------------------------------------------------------------------------> MSB */
    //first uuid, 16bit, [12],[13] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xEE, 0x00, 0x00, 0x00,
    //second uuid, 32bit, [12], [13], [14], [15] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00,
};

// The length of adv data must be less than 31 bytes
//static uint8_t test_manufacturer[TEST_MANUFACTURER_DATA_LEN] =  {0x12, 0x23, 0x45, 0x56};
//adv data
static esp_ble_adv_data_t adv_data = {
    .set_scan_rsp = false,
    .include_name = true,
    .include_txpower = false,
    .min_interval = 0x0006, //slave connection min interval, Time = min_interval * 1.25 msec
    .max_interval = 0x0010, //slave connection max interval, Time = max_interval * 1.25 msec
    .appearance = 0x00,
    .manufacturer_len = 0, //TEST_MANUFACTURER_DATA_LEN,
    .p_manufacturer_data =  NULL, //&test_manufacturer[0],
    .service_data_len = 0,
    .p_service_data = NULL,
    .service_uuid_len = sizeof(adv_service_uuid128),
    .p_service_uuid = adv_service_uuid128,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};
// scan response data
static esp_ble_adv_data_t scan_rsp_data = {
    .set_scan_rsp = true,
    .include_name = true,
    .include_txpower = true,
    //.min_interval = 0x0006,
    //.max_interval = 0x0010,
    .appearance = 0x00,
    .manufacturer_len = 0, //TEST_MANUFACTURER_DATA_LEN,
    .p_manufacturer_data =  NULL, //&test_manufacturer[0],
    .service_data_len = 0,
    .p_service_data = NULL,
    .service_uuid_len = sizeof(adv_service_uuid128),
    .p_service_uuid = adv_service_uuid128,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

#endif /* CONFIG_SET_RAW_ADV_DATA */

static esp_ble_adv_params_t adv_params = {
    .adv_int_min        = 0x20,
    .adv_int_max        = 0x40,
    .adv_type           = ADV_TYPE_IND,
    .own_addr_type      = BLE_ADDR_TYPE_PUBLIC,
    //.peer_addr            =
    //.peer_addr_type       =
    .channel_map        = ADV_CHNL_ALL,
    .adv_filter_policy = ADV_FILTER_ALLOW_SCAN_ANY_CON_ANY,
};

#define PROFILE_NUM 2
#define PROFILE_A_APP_ID 0
#define PROFILE_B_APP_ID 1

struct gatts_profile_inst {
    esp_gatts_cb_t gatts_cb;
    uint16_t gatts_if;
    uint16_t app_id;
    uint16_t conn_id;
    uint16_t service_handle;
    esp_gatt_srvc_id_t service_id;
    uint16_t char_handle;
    esp_bt_uuid_t char_uuid;
    esp_gatt_perm_t perm;
    esp_gatt_char_prop_t property;
    uint16_t descr_handle;
    esp_bt_uuid_t descr_uuid;
};

/* One gatt-based profile one app_id and one gatts_if, this array will store the gatts_if returned by ESP_GATTS_REG_EVT */
static struct gatts_profile_inst gl_profile_tab[PROFILE_NUM] = {
    [PROFILE_A_APP_ID] = {
        .gatts_cb = gatts_profile_a_event_handler,
        .gatts_if = ESP_GATT_IF_NONE,       /* Not get the gatt_if, so initial is ESP_GATT_IF_NONE */
    },
    [PROFILE_B_APP_ID] = {
        .gatts_cb = gatts_profile_b_event_handler,                   /* This demo does not implement, similar as profile A */
        .gatts_if = ESP_GATT_IF_NONE,       /* Not get the gatt_if, so initial is ESP_GATT_IF_NONE */
    },
};

typedef struct {
    uint8_t                 *prepare_buf;
    int                     prepare_len;
} prepare_type_env_t;

static prepare_type_env_t a_prepare_write_env;
static prepare_type_env_t b_prepare_write_env;

void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);
void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);

static void gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
    switch (event) {
#ifdef CONFIG_SET_RAW_ADV_DATA
    case ESP_GAP_BLE_ADV_DATA_RAW_SET_COMPLETE_EVT:
        adv_config_done &= (~adv_config_flag);
        if (adv_config_done==0){
            esp_ble_gap_start_advertising(&adv_params);
        }
        break;
    case ESP_GAP_BLE_SCAN_RSP_DATA_RAW_SET_COMPLETE_EVT:
        adv_config_done &= (~scan_rsp_config_flag);
        if (adv_config_done==0){
            esp_ble_gap_start_advertising(&adv_params);
        }
        break;
#else
    case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
        adv_config_done &= (~adv_config_flag);
        if (adv_config_done == 0){
            esp_ble_gap_start_advertising(&adv_params);
        }
        break;
    case ESP_GAP_BLE_SCAN_RSP_DATA_SET_COMPLETE_EVT:
        adv_config_done &= (~scan_rsp_config_flag);
        if (adv_config_done == 0){
            esp_ble_gap_start_advertising(&adv_params);
        }
        break;
#endif
    case ESP_GAP_BLE_ADV_START_COMPLETE_EVT:
        //advertising start complete event to indicate advertising start successfully or failed
        if (param->adv_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
            ESP_LOGE(GATTS_TAG, "Advertising start failed, status %d", param->adv_start_cmpl.status);
            break;
        }
        ESP_LOGI(GATTS_TAG, "Advertising start successfully");
        break;
    case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
        if (param->adv_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
            ESP_LOGE(GATTS_TAG, "Advertising stop failed, status %d", param->adv_stop_cmpl.status);
            break;
        }
        ESP_LOGI(GATTS_TAG, "Advertising stop successfully");
        break;
    case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT:
         ESP_LOGI(GATTS_TAG, "Connection params update, status %d, conn_int %d, latency %d, timeout %d",
                  param->update_conn_params.status,
                  param->update_conn_params.conn_int,
                  param->update_conn_params.latency,
                  param->update_conn_params.timeout);
        break;
    case ESP_GAP_BLE_SET_PKT_LENGTH_COMPLETE_EVT:
        ESP_LOGI(GATTS_TAG, "Packet length update, status %d, rx %d, tx %d",
                  param->pkt_data_length_cmpl.status,
                  param->pkt_data_length_cmpl.params.rx_len,
                  param->pkt_data_length_cmpl.params.tx_len);
        break;
    default:
        break;
    }
}

void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){
    esp_gatt_status_t status = ESP_GATT_OK;
    if (param->write.need_rsp){
        if (param->write.is_prep) {
            if (param->write.offset > PREPARE_BUF_MAX_SIZE) {
                status = ESP_GATT_INVALID_OFFSET;
            } else if ((param->write.offset + param->write.len) > PREPARE_BUF_MAX_SIZE) {
                status = ESP_GATT_INVALID_ATTR_LEN;
            }
            if (status == ESP_GATT_OK && prepare_write_env->prepare_buf == NULL) {
                prepare_write_env->prepare_buf = (uint8_t *)malloc(PREPARE_BUF_MAX_SIZE*sizeof(uint8_t));
                prepare_write_env->prepare_len = 0;
                if (prepare_write_env->prepare_buf == NULL) {
                    ESP_LOGE(GATTS_TAG, "Gatt_server prep no mem");
                    status = ESP_GATT_NO_RESOURCES;
                }
            }

            esp_gatt_rsp_t *gatt_rsp = (esp_gatt_rsp_t *)malloc(sizeof(esp_gatt_rsp_t));
            if (gatt_rsp) {
                gatt_rsp->attr_value.len = param->write.len;
                gatt_rsp->attr_value.handle = param->write.handle;
                gatt_rsp->attr_value.offset = param->write.offset;
                gatt_rsp->attr_value.auth_req = ESP_GATT_AUTH_REQ_NONE;
                memcpy(gatt_rsp->attr_value.value, param->write.value, param->write.len);
                esp_err_t response_err = esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, gatt_rsp);
                if (response_err != ESP_OK){
                    ESP_LOGE(GATTS_TAG, "Send response error\n");
                }
                free(gatt_rsp);
            } else {
                ESP_LOGE(GATTS_TAG, "malloc failed, no resource to send response error\n");
                status = ESP_GATT_NO_RESOURCES;
            }
            if (status != ESP_GATT_OK){
                return;
            }
            memcpy(prepare_write_env->prepare_buf + param->write.offset,
                   param->write.value,
                   param->write.len);
            prepare_write_env->prepare_len += param->write.len;

        }else{
            esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, NULL);
        }
    }
}

void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){
    if (param->exec_write.exec_write_flag == ESP_GATT_PREP_WRITE_EXEC){
        ESP_LOG_BUFFER_HEX(GATTS_TAG, prepare_write_env->prepare_buf, prepare_write_env->prepare_len);
    }else{
        ESP_LOGI(GATTS_TAG,"Prepare write cancel");
    }
    if (prepare_write_env->prepare_buf) {
        free(prepare_write_env->prepare_buf);
        prepare_write_env->prepare_buf = NULL;
    }
    prepare_write_env->prepare_len = 0;
}

static void gatts_profile_a_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param) {
    switch (event) {
    case ESP_GATTS_REG_EVT:
        ESP_LOGI(GATTS_TAG, "GATT server register, status %d, app_id %d, gatts_if %d", param->reg.status, param->reg.app_id, gatts_if);
        gl_profile_tab[PROFILE_A_APP_ID].service_id.is_primary = true;
        gl_profile_tab[PROFILE_A_APP_ID].service_id.id.inst_id = 0x00;
        gl_profile_tab[PROFILE_A_APP_ID].service_id.id.uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_A_APP_ID].service_id.id.uuid.uuid.uuid16 = GATTS_SERVICE_UUID_TEST_A;

        esp_err_t set_dev_name_ret = esp_ble_gap_set_device_name(test_device_name);
        if (set_dev_name_ret){
            ESP_LOGE(GATTS_TAG, "set device name failed, error code = %x", set_dev_name_ret);
        }
#ifdef CONFIG_EXAMPLE_SET_RAW_ADV_DATA
        esp_err_t raw_adv_ret = esp_ble_gap_config_adv_data_raw(raw_adv_data, sizeof(raw_adv_data));
        if (raw_adv_ret){
            ESP_LOGE(GATTS_TAG, "config raw adv data failed, error code = %x ", raw_adv_ret);
        }
        adv_config_done |= adv_config_flag;
        esp_err_t raw_scan_ret = esp_ble_gap_config_scan_rsp_data_raw(raw_scan_rsp_data, sizeof(raw_scan_rsp_data));
        if (raw_scan_ret){
            ESP_LOGE(GATTS_TAG, "config raw scan rsp data failed, error code = %x", raw_scan_ret);
        }
        adv_config_done |= scan_rsp_config_flag;
#else
        //config adv data
        esp_err_t ret = esp_ble_gap_config_adv_data(&adv_data);
        if (ret){
            ESP_LOGE(GATTS_TAG, "config adv data failed, error code = %x", ret);
        }
        adv_config_done |= adv_config_flag;
        //config scan response data
        ret = esp_ble_gap_config_adv_data(&scan_rsp_data);
        if (ret){
            ESP_LOGE(GATTS_TAG, "config scan response data failed, error code = %x", ret);
        }
        adv_config_done |= scan_rsp_config_flag;

#endif
        esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_A_APP_ID].service_id, GATTS_NUM_HANDLE_TEST_A);
        break;
    case ESP_GATTS_READ_EVT: {
        ESP_LOGI(GATTS_TAG,
                    "Characteristic read request: conn_id=%d, trans_id=%" PRIu32 ", handle=%d, is_long=%d, offset=%d, need_rsp=%d",
                    param->read.conn_id, param->read.trans_id, param->read.handle,
                    param->read.is_long, param->read.offset, param->read.need_rsp);

        // If no response is needed, exit early (stack handles it automatically)
        if (!param->read.need_rsp) {
            return;
        }

        esp_gatt_rsp_t rsp;
        memset(&rsp, 0, sizeof(esp_gatt_rsp_t));
        rsp.attr_value.handle = param->read.handle;

        // Handle descriptor read request
        if (param->read.handle == gl_profile_tab[PROFILE_A_APP_ID].descr_handle) {
            memcpy(rsp.attr_value.value, &descr_value, 2);
            rsp.attr_value.len = 2;
            esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id, ESP_GATT_OK, &rsp);
            return;
        }

        // Handle characteristic read request
        if (param->read.handle == gl_profile_tab[PROFILE_A_APP_ID].char_handle) {
            uint16_t offset = param->read.offset;

            // Validate read offset
            if (param->read.is_long && offset > CONFIG_EXAMPLE_CHAR_READ_DATA_LEN) {
                ESP_LOGW(GATTS_TAG, "Read offset (%d) out of range (0-%d)", offset, CONFIG_EXAMPLE_CHAR_READ_DATA_LEN);
                rsp.attr_value.len = 0;
                esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id, ESP_GATT_INVALID_OFFSET, &rsp);
                return;
            }

            // Determine response length based on MTU
            uint16_t mtu_size = local_mtu - 1;  // ATT header (1 byte)
            uint16_t send_len = (CONFIG_EXAMPLE_CHAR_READ_DATA_LEN - offset > mtu_size) ? mtu_size : (CONFIG_EXAMPLE_CHAR_READ_DATA_LEN - offset);

            memcpy(rsp.attr_value.value, &char_value_read[offset], send_len);
            rsp.attr_value.len = send_len;

            // Send response to GATT client
            esp_err_t err = esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id, ESP_GATT_OK, &rsp);
            if (err != ESP_OK) {
                ESP_LOGE(GATTS_TAG, "Failed to send response: %s", esp_err_to_name(err));
            }
        }
        break;
    }
    case ESP_GATTS_WRITE_EVT: {
        ESP_LOGI(GATTS_TAG, "Characteristic write, conn_id %d, trans_id %" PRIu32 ", handle %d", param->write.conn_id, param->write.trans_id, param->write.handle);
        if (!param->write.is_prep){
            ESP_LOGI(GATTS_TAG, "value len %d, value ", param->write.len);
            ESP_LOG_BUFFER_HEX(GATTS_TAG, param->write.value, param->write.len);
            if (gl_profile_tab[PROFILE_A_APP_ID].descr_handle == param->write.handle && param->write.len == 2){
                descr_value = param->write.value[1]<<8 | param->write.value[0];
                if (descr_value == 0x0001){
                    if (a_property & ESP_GATT_CHAR_PROP_BIT_NOTIFY){
                        ESP_LOGI(GATTS_TAG, "Notification enable");
                        uint8_t notify_data[15];
                        for (int i = 0; i < sizeof(notify_data); ++i)
                        {
                            notify_data[i] = i%0xff;
                        }
                        //the size of notify_data[] need less than MTU size
                        esp_ble_gatts_send_indicate(gatts_if, param->write.conn_id, gl_profile_tab[PROFILE_A_APP_ID].char_handle,
                                                sizeof(notify_data), notify_data, false);
                    }
                }else if (descr_value == 0x0002){
                    if (a_property & ESP_GATT_CHAR_PROP_BIT_INDICATE){
                        ESP_LOGI(GATTS_TAG, "Indication enable");
                        uint8_t indicate_data[15];
                        for (int i = 0; i < sizeof(indicate_data); ++i)
                        {
                            indicate_data[i] = i%0xff;
                        }
                        //the size of indicate_data[] need less than MTU size
                        esp_ble_gatts_send_indicate(gatts_if, param->write.conn_id, gl_profile_tab[PROFILE_A_APP_ID].char_handle,
                                                sizeof(indicate_data), indicate_data, true);
                    }
                }
                else if (descr_value == 0x0000){
                    ESP_LOGI(GATTS_TAG, "Notification/Indication disable");
                }else{
                    ESP_LOGE(GATTS_TAG, "Unknown descriptor value");
                    ESP_LOG_BUFFER_HEX(GATTS_TAG, param->write.value, param->write.len);
                }

            }
        }
        example_write_event_env(gatts_if, &a_prepare_write_env, param);
        break;
    }
    case ESP_GATTS_EXEC_WRITE_EVT:
        ESP_LOGI(GATTS_TAG,"Execute write");
        esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, ESP_GATT_OK, NULL);
        example_exec_write_event_env(&a_prepare_write_env, param);
        break;
    case ESP_GATTS_MTU_EVT:
        ESP_LOGI(GATTS_TAG, "MTU exchange, MTU %d", param->mtu.mtu);
        local_mtu = param->mtu.mtu;
        break;
    case ESP_GATTS_UNREG_EVT:
        break;
    case ESP_GATTS_CREATE_EVT:
        ESP_LOGI(GATTS_TAG, "Service create, status %d, service_handle %d", param->create.status, param->create.service_handle);
        gl_profile_tab[PROFILE_A_APP_ID].service_handle = param->create.service_handle;
        gl_profile_tab[PROFILE_A_APP_ID].char_uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_A_APP_ID].char_uuid.uuid.uuid16 = GATTS_CHAR_UUID_TEST_A;

        esp_ble_gatts_start_service(gl_profile_tab[PROFILE_A_APP_ID].service_handle);
        a_property = ESP_GATT_CHAR_PROP_BIT_READ | ESP_GATT_CHAR_PROP_BIT_WRITE | ESP_GATT_CHAR_PROP_BIT_NOTIFY;
        esp_err_t add_char_ret = esp_ble_gatts_add_char(gl_profile_tab[PROFILE_A_APP_ID].service_handle, &gl_profile_tab[PROFILE_A_APP_ID].char_uuid,
                                                        ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
                                                        a_property,
                                                        &gatts_demo_char1_val, NULL);
        if (add_char_ret){
            ESP_LOGE(GATTS_TAG, "add char failed, error code =%x",add_char_ret);
        }
        break;
    case ESP_GATTS_ADD_INCL_SRVC_EVT:
        break;
    case ESP_GATTS_ADD_CHAR_EVT: {
        uint16_t length = 0;
        const uint8_t *prf_char;

        ESP_LOGI(GATTS_TAG, "Characteristic add, status %d, attr_handle %d, service_handle %d",
                param->add_char.status, param->add_char.attr_handle, param->add_char.service_handle);
        gl_profile_tab[PROFILE_A_APP_ID].char_handle = param->add_char.attr_handle;
        gl_profile_tab[PROFILE_A_APP_ID].descr_uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_A_APP_ID].descr_uuid.uuid.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG;
        esp_err_t get_attr_ret = esp_ble_gatts_get_attr_value(param->add_char.attr_handle,  &length, &prf_char);
        if (get_attr_ret == ESP_FAIL){
            ESP_LOGE(GATTS_TAG, "ILLEGAL HANDLE");
        }

        ESP_LOGI(GATTS_TAG, "the gatts demo char length = %x", length);
        for(int i = 0; i < length; i++){
            ESP_LOGI(GATTS_TAG, "prf_char[%x] =%x",i,prf_char[i]);
        }
        esp_err_t add_descr_ret = esp_ble_gatts_add_char_descr(gl_profile_tab[PROFILE_A_APP_ID].service_handle, &gl_profile_tab[PROFILE_A_APP_ID].descr_uuid,
                                                                ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE, NULL, NULL);
        if (add_descr_ret){
            ESP_LOGE(GATTS_TAG, "add char descr failed, error code =%x", add_descr_ret);
        }
        break;
    }
    case ESP_GATTS_ADD_CHAR_DESCR_EVT:
        gl_profile_tab[PROFILE_A_APP_ID].descr_handle = param->add_char_descr.attr_handle;
        ESP_LOGI(GATTS_TAG, "Descriptor add, status %d, attr_handle %d, service_handle %d",
                 param->add_char_descr.status, param->add_char_descr.attr_handle, param->add_char_descr.service_handle);
        break;
    case ESP_GATTS_DELETE_EVT:
        break;
    case ESP_GATTS_START_EVT:
        ESP_LOGI(GATTS_TAG, "Service start, status %d, service_handle %d",
                 param->start.status, param->start.service_handle);
        break;
    case ESP_GATTS_STOP_EVT:
        break;
    case ESP_GATTS_CONNECT_EVT: {
        esp_ble_conn_update_params_t conn_params = {0};
        memcpy(conn_params.bda, param->connect.remote_bda, sizeof(esp_bd_addr_t));
        /* For the IOS system, please reference the apple official documents about the ble connection parameters restrictions. */
        conn_params.latency = 0;
        conn_params.max_int = 0x20;    // max_int = 0x20*1.25ms = 40ms
        conn_params.min_int = 0x10;    // min_int = 0x10*1.25ms = 20ms
        conn_params.timeout = 400;    // timeout = 400*10ms = 4000ms
        ESP_LOGI(GATTS_TAG, "Connected, conn_id %u, remote "ESP_BD_ADDR_STR"",
                 param->connect.conn_id, ESP_BD_ADDR_HEX(param->connect.remote_bda));
        gl_profile_tab[PROFILE_A_APP_ID].conn_id = param->connect.conn_id;
        //start sent the update connection parameters to the peer device.
        esp_ble_gap_update_conn_params(&conn_params);
        break;
    }
    case ESP_GATTS_DISCONNECT_EVT:
        ESP_LOGI(GATTS_TAG, "Disconnected, remote "ESP_BD_ADDR_STR", reason 0x%02x",
                 ESP_BD_ADDR_HEX(param->disconnect.remote_bda), param->disconnect.reason);
        esp_ble_gap_start_advertising(&adv_params);
        local_mtu = 23; // Reset MTU for a single connection
        break;
    case ESP_GATTS_CONF_EVT:
        ESP_LOGI(GATTS_TAG, "Confirm receive, status %d, attr_handle %d", param->conf.status, param->conf.handle);
        if (param->conf.status != ESP_GATT_OK){
            ESP_LOG_BUFFER_HEX(GATTS_TAG, param->conf.value, param->conf.len);
        }
        break;
    case ESP_GATTS_OPEN_EVT:
    case ESP_GATTS_CANCEL_OPEN_EVT:
    case ESP_GATTS_CLOSE_EVT:
    case ESP_GATTS_LISTEN_EVT:
    case ESP_GATTS_CONGEST_EVT:
    default:
        break;
    }
}

static void gatts_profile_b_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param) {
    switch (event) {
    case ESP_GATTS_REG_EVT:
        ESP_LOGI(GATTS_TAG, "GATT server register, status %d, app_id %d, gatts_if %d", param->reg.status, param->reg.app_id, gatts_if);
        gl_profile_tab[PROFILE_B_APP_ID].service_id.is_primary = true;
        gl_profile_tab[PROFILE_B_APP_ID].service_id.id.inst_id = 0x00;
        gl_profile_tab[PROFILE_B_APP_ID].service_id.id.uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_B_APP_ID].service_id.id.uuid.uuid.uuid16 = GATTS_SERVICE_UUID_TEST_B;

        esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_B_APP_ID].service_id, GATTS_NUM_HANDLE_TEST_B);
        break;
    case ESP_GATTS_READ_EVT: {
        ESP_LOGI(GATTS_TAG, "Characteristic read, conn_id %d, trans_id %" PRIu32 ", handle %d", param->read.conn_id, param->read.trans_id, param->read.handle);
        esp_gatt_rsp_t rsp;
        memset(&rsp, 0, sizeof(esp_gatt_rsp_t));
        rsp.attr_value.handle = param->read.handle;
        rsp.attr_value.len = 4;
        rsp.attr_value.value[0] = 0xde;
        rsp.attr_value.value[1] = 0xed;
        rsp.attr_value.value[2] = 0xbe;
        rsp.attr_value.value[3] = 0xef;
        esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id,
                                    ESP_GATT_OK, &rsp);
        break;
    }
    case ESP_GATTS_WRITE_EVT: {
        ESP_LOGI(GATTS_TAG, "Characteristic write, conn_id %d, trans_id %" PRIu32 ", handle %d", param->write.conn_id, param->write.trans_id, param->write.handle);
        if (!param->write.is_prep){
            ESP_LOGI(GATTS_TAG, "value len %d, value ", param->write.len);
            ESP_LOG_BUFFER_HEX(GATTS_TAG, param->write.value, param->write.len);
            if (gl_profile_tab[PROFILE_B_APP_ID].descr_handle == param->write.handle && param->write.len == 2){
                uint16_t descr_value= param->write.value[1]<<8 | param->write.value[0];
                if (descr_value == 0x0001){
                    if (b_property & ESP_GATT_CHAR_PROP_BIT_NOTIFY) {
                        ESP_LOGI(GATTS_TAG, "Notification enable");
                        uint8_t notify_data[15];
                        for (int i = 0; i < sizeof(notify_data); ++i)
                        {
                            notify_data[i] = i%0xff;
                        }
                        //the size of notify_data[] need less than MTU size
                        esp_ble_gatts_send_indicate(gatts_if, param->write.conn_id, gl_profile_tab[PROFILE_B_APP_ID].char_handle,
                                                sizeof(notify_data), notify_data, false);
                    }
                }else if (descr_value == 0x0002){
                    if (b_property & ESP_GATT_CHAR_PROP_BIT_INDICATE){
                        ESP_LOGI(GATTS_TAG, "Indication enable");
                        uint8_t indicate_data[15];
                        for (int i = 0; i < sizeof(indicate_data); ++i)
                        {
                            indicate_data[i] = i%0xff;
                        }
                        //the size of indicate_data[] need less than MTU size
                        esp_ble_gatts_send_indicate(gatts_if, param->write.conn_id, gl_profile_tab[PROFILE_B_APP_ID].char_handle,
                                                sizeof(indicate_data), indicate_data, true);
                    }
                }
                else if (descr_value == 0x0000){
                    ESP_LOGI(GATTS_TAG, "Notification/Indication disable");
                }else{
                    ESP_LOGE(GATTS_TAG, "Unknown value");
                }

            }
        }
        example_write_event_env(gatts_if, &b_prepare_write_env, param);
        break;
    }
    case ESP_GATTS_EXEC_WRITE_EVT:
        ESP_LOGI(GATTS_TAG,"Execute write");
        esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, ESP_GATT_OK, NULL);
        example_exec_write_event_env(&b_prepare_write_env, param);
        break;
    case ESP_GATTS_MTU_EVT:
        ESP_LOGI(GATTS_TAG, "MTU exchange, MTU %d", param->mtu.mtu);
        break;
    case ESP_GATTS_UNREG_EVT:
        break;
    case ESP_GATTS_CREATE_EVT:
        ESP_LOGI(GATTS_TAG, "Service create, status %d,  service_handle %d", param->create.status, param->create.service_handle);
        gl_profile_tab[PROFILE_B_APP_ID].service_handle = param->create.service_handle;
        gl_profile_tab[PROFILE_B_APP_ID].char_uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_B_APP_ID].char_uuid.uuid.uuid16 = GATTS_CHAR_UUID_TEST_B;

        esp_ble_gatts_start_service(gl_profile_tab[PROFILE_B_APP_ID].service_handle);
        b_property = ESP_GATT_CHAR_PROP_BIT_READ | ESP_GATT_CHAR_PROP_BIT_WRITE | ESP_GATT_CHAR_PROP_BIT_NOTIFY;
        esp_err_t add_char_ret =esp_ble_gatts_add_char( gl_profile_tab[PROFILE_B_APP_ID].service_handle, &gl_profile_tab[PROFILE_B_APP_ID].char_uuid,
                                                        ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
                                                        b_property,
                                                        NULL, NULL);
        if (add_char_ret){
            ESP_LOGE(GATTS_TAG, "add char failed, error code =%x",add_char_ret);
        }
        break;
    case ESP_GATTS_ADD_INCL_SRVC_EVT:
        break;
    case ESP_GATTS_ADD_CHAR_EVT:
        ESP_LOGI(GATTS_TAG, "Characteristic add, status %d, attr_handle %d, service_handle %d",
                 param->add_char.status, param->add_char.attr_handle, param->add_char.service_handle);

        gl_profile_tab[PROFILE_B_APP_ID].char_handle = param->add_char.attr_handle;
        gl_profile_tab[PROFILE_B_APP_ID].descr_uuid.len = ESP_UUID_LEN_16;
        gl_profile_tab[PROFILE_B_APP_ID].descr_uuid.uuid.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG;
        esp_ble_gatts_add_char_descr(gl_profile_tab[PROFILE_B_APP_ID].service_handle, &gl_profile_tab[PROFILE_B_APP_ID].descr_uuid,
                                     ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
                                     NULL, NULL);
        break;
    case ESP_GATTS_ADD_CHAR_DESCR_EVT:
        gl_profile_tab[PROFILE_B_APP_ID].descr_handle = param->add_char_descr.attr_handle;
        ESP_LOGI(GATTS_TAG, "Descriptor add, status %d, attr_handle %d, service_handle %d",
                 param->add_char_descr.status, param->add_char_descr.attr_handle, param->add_char_descr.service_handle);
        break;
    case ESP_GATTS_DELETE_EVT:
        break;
    case ESP_GATTS_START_EVT:
        ESP_LOGI(GATTS_TAG, "Service start, status %d, service_handle %d",
                 param->start.status, param->start.service_handle);
        break;
    case ESP_GATTS_STOP_EVT:
        break;
    case ESP_GATTS_CONNECT_EVT:
        ESP_LOGI(GATTS_TAG, "Connected, conn_id %d, remote "ESP_BD_ADDR_STR"",
                 param->connect.conn_id, ESP_BD_ADDR_HEX(param->connect.remote_bda));
        gl_profile_tab[PROFILE_B_APP_ID].conn_id = param->connect.conn_id;
        break;
    case ESP_GATTS_CONF_EVT:
        ESP_LOGI(GATTS_TAG, "Confirm receive, status %d, attr_handle %d", param->conf.status, param->conf.handle);
        if (param->conf.status != ESP_GATT_OK){
            ESP_LOG_BUFFER_HEX(GATTS_TAG, param->conf.value, param->conf.len);
        }
    break;
    case ESP_GATTS_DISCONNECT_EVT:
    case ESP_GATTS_OPEN_EVT:
    case ESP_GATTS_CANCEL_OPEN_EVT:
    case ESP_GATTS_CLOSE_EVT:
    case ESP_GATTS_LISTEN_EVT:
    case ESP_GATTS_CONGEST_EVT:
    default:
        break;
    }
}

static void gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param)
{
    /* If event is register event, store the gatts_if for each profile */
    if (event == ESP_GATTS_REG_EVT) {
        if (param->reg.status == ESP_GATT_OK) {
            gl_profile_tab[param->reg.app_id].gatts_if = gatts_if;
        } else {
            ESP_LOGI(GATTS_TAG, "Reg app failed, app_id %04x, status %d",
                    param->reg.app_id,
                    param->reg.status);
            return;
        }
    }

    /* If the gatts_if equal to profile A, call profile A cb handler,
     * so here call each profile's callback */
    do {
        int idx;
        for (idx = 0; idx < PROFILE_NUM; idx++) {
            if (gatts_if == ESP_GATT_IF_NONE || /* ESP_GATT_IF_NONE, not specify a certain gatt_if, need to call every profile cb function */
                    gatts_if == gl_profile_tab[idx].gatts_if) {
                if (gl_profile_tab[idx].gatts_cb) {
                    gl_profile_tab[idx].gatts_cb(event, gatts_if, param);
                }
            }
        }
    } while (0);
}

void app_main(void)
{
    esp_err_t ret;

    // Initialize NVS.
    ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        ESP_ERROR_CHECK(nvs_flash_erase());
        ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK( ret );

    #if CONFIG_EXAMPLE_CI_PIPELINE_ID
    memcpy(test_device_name, esp_bluedroid_get_example_name(), ESP_BLE_ADV_NAME_LEN_MAX);
    #endif

    ESP_ERROR_CHECK(esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT));

    esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
    ret = esp_bt_controller_init(&bt_cfg);
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s initialize controller failed: %s", __func__, esp_err_to_name(ret));
        return;
    }

    ret = esp_bt_controller_enable(ESP_BT_MODE_BLE);
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s enable controller failed: %s", __func__, esp_err_to_name(ret));
        return;
    }

    ret = esp_bluedroid_init();
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s init bluetooth failed: %s", __func__, esp_err_to_name(ret));
        return;
    }
    ret = esp_bluedroid_enable();
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s enable bluetooth failed: %s", __func__, esp_err_to_name(ret));
        return;
    }
    // Note: Avoid performing time-consuming operations within callback functions.
    ret = esp_ble_gatts_register_callback(gatts_event_handler);
    if (ret){
        ESP_LOGE(GATTS_TAG, "gatts register error, error code = %x", ret);
        return;
    }
    ret = esp_ble_gap_register_callback(gap_event_handler);
    if (ret){
        ESP_LOGE(GATTS_TAG, "gap register error, error code = %x", ret);
        return;
    }
    ret = esp_ble_gatts_app_register(PROFILE_A_APP_ID);
    if (ret){
        ESP_LOGE(GATTS_TAG, "gatts app register error, error code = %x", ret);
        return;
    }
    ret = esp_ble_gatts_app_register(PROFILE_B_APP_ID);
    if (ret){
        ESP_LOGE(GATTS_TAG, "gatts app register error, error code = %x", ret);
        return;
    }
    esp_err_t local_mtu_ret = esp_ble_gatt_set_local_mtu(500);
    if (local_mtu_ret){
        ESP_LOGE(GATTS_TAG, "set local  MTU failed, error code = %x", local_mtu_ret);
    }

    return;
}