/*
 * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Unlicense OR CC0-1.0
 */

/****************************************************************************
* The demo shows BLE and classic Bluetooth coexistence. You can use BLE GATT server and classic bluetooth A2DP together.
* The BLE GATT server part of the demo creates a GATT service and then starts advertising, waiting to be connected by a GATT client.
* After the program is started, a GATT client can discover the device named "ESP_COEX_BLE_DEMO". Once the connection is established,
* GATT client can read or write data to the device. It can also receive notification or indication data.
* Attention: If you test the demo with iPhone, BLE GATT server adv name will change to "ESP_COEX_A2DP_DEMO" after you connect it.
* The classic bluetooth A2DP part of the demo implements Advanced Audio Distribution Profile to receive an audio stream.
* After the program is started, other bluetooth devices such as smart phones can discover the device named "ESP_COEX_A2DP_DEMO".
* Once the connection is established, audio data can be transmitted. This will be visible in the application log including a count
* of audio data packets.
****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "nvs.h"
#include "nvs_flash.h"
#include "esp_system.h"
#include "esp_log.h"

#include "esp_bt.h"
#include "bt_app_core.h"
#include "bt_app_av.h"
#include "esp_bt_main.h"
#include "esp_bt_device.h"
#include "esp_gap_bt_api.h"
#include "esp_a2dp_api.h"
#include "esp_avrc_api.h"
#ifdef CONFIG_EXAMPLE_A2DP_SINK_OUTPUT_INTERNAL_DAC
#include "driver/dac_conti.h"
#else
#include "driver/i2s_std.h"
#endif

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

#define BT_BLE_COEX_TAG             "BT_BLE_COEX"
#define BT_DEVICE_NAME              "ESP_COEX_A2DP_DEMO"
#define BLE_ADV_NAME                "ESP_COEX_BLE_DEMO"

#define GATTS_SERVICE_UUID_A        0x00FF
#define GATTS_CHAR_UUID_A           0xFF01
#define GATTS_DESCR_UUID_A          0x3333
#define GATTS_NUM_HANDLE_A          4

#define GATTS_SERVICE_UUID_B        0x00EE
#define GATTS_CHAR_UUID_B           0xEE01
#define GATTS_DESCR_UUID_B          0x2222
#define GATTS_NUM_HANDLE_B          4

#define GATTS_DEMO_CHAR_VAL_LEN_MAX 0x40
#define PREPARE_BUF_MAX_SIZE        1024
#define PROFILE_NUM                 2
#define PROFILE_A_APP_ID            0
#define PROFILE_B_APP_ID            1

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;

#ifndef CONFIG_EXAMPLE_A2DP_SINK_OUTPUT_INTERNAL_DAC
i2s_chan_handle_t tx_chan;
#else
dac_conti_handle_t tx_chan;
#endif

//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);
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);

/* event for handler "bt_av_hdl_stack_up */
enum {
    BT_APP_EVT_STACK_UP = 0,
};
static uint8_t ble_char_value_str[] = {0x11, 0x22, 0x33};
esp_gatt_char_prop_t a_property = 0;
esp_gatt_char_prop_t b_property = 0;

esp_attr_value_t gatts_initial_char_val = {
    .attr_max_len = GATTS_DEMO_CHAR_VAL_LEN_MAX,
    .attr_len     = sizeof(ble_char_value_str),
    .attr_value   = ble_char_value_str,
};

static esp_ble_adv_params_t adv_params = {
    .adv_int_min        = 0x060,
    .adv_int_max        = 0x060,
    .adv_type           = ADV_TYPE_IND,
    .own_addr_type      = BLE_ADDR_TYPE_RANDOM,
    .channel_map        = ADV_CHNL_ALL,
    .adv_filter_policy = ADV_FILTER_ALLOW_SCAN_ANY_CON_ANY,
};

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 */
    },
};
static void ble_init_adv_data(const char *name)
{
    int len = strlen(name);
    uint8_t raw_adv_data[len+5];
    //flag
    raw_adv_data[0] = 2;
    raw_adv_data[1] = ESP_BT_EIR_TYPE_FLAGS;
    raw_adv_data[2] = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT);
    //adv name
    raw_adv_data[3] = len + 1;
    raw_adv_data[4] = ESP_BLE_AD_TYPE_NAME_CMPL;
    for (int i = 0;i < len;i++)
    {
        raw_adv_data[i+5] = *(name++);
    }
    //The length of adv data must be less than 31 bytes
    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(BT_BLE_COEX_TAG, "config raw adv data failed, error code = 0x%x ", raw_adv_ret);
    }
    esp_err_t raw_scan_ret = esp_ble_gap_config_scan_rsp_data_raw(raw_adv_data, sizeof(raw_adv_data));
    if (raw_scan_ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "config raw scan rsp data failed, error code = 0x%x", raw_scan_ret);
    }
}

static void gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
    switch (event) {
    case ESP_GAP_BLE_ADV_DATA_RAW_SET_COMPLETE_EVT:
        //esp_ble_gap_start_advertising(&adv_params);
        break;
    case ESP_GAP_BLE_SCAN_RSP_DATA_RAW_SET_COMPLETE_EVT:
        esp_ble_gap_start_advertising(&adv_params);
        break;
    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(BT_BLE_COEX_TAG, "Advertising start failed\n");
        }else {
            ESP_LOGI(BT_BLE_COEX_TAG, "Start adv successfully\n");
        }
        break;
    case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
        if (param->adv_stop_cmpl.status != ESP_BT_STATUS_SUCCESS) {
            ESP_LOGE(BT_BLE_COEX_TAG, "Advertising stop failed\n");
        }
        else {
            ESP_LOGI(BT_BLE_COEX_TAG, "Stop adv successfully\n");
        }
        break;
    case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT:
         ESP_LOGI(BT_BLE_COEX_TAG, "update connection params status = %d, min_int = %d, max_int = %d,conn_int = %d,latency = %d, timeout = %d",
                  param->update_conn_params.status,
                  param->update_conn_params.min_int,
                  param->update_conn_params.max_int,
                  param->update_conn_params.conn_int,
                  param->update_conn_params.latency,
                  param->update_conn_params.timeout);
        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 (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(BT_BLE_COEX_TAG, "Gatt_server prep no mem\n");
                    status = ESP_GATT_NO_RESOURCES;
                }
            } else {
                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;
                }
            }

            esp_gatt_rsp_t *gatt_rsp = (esp_gatt_rsp_t *)malloc(sizeof(esp_gatt_rsp_t));
            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(BT_BLE_COEX_TAG, "Send response error\n");
            }
            free(gatt_rsp);
            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(BT_BLE_COEX_TAG, prepare_write_env->prepare_buf, prepare_write_env->prepare_len);
    }else{
        ESP_LOGI(BT_BLE_COEX_TAG,"ESP_GATT_PREP_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(BT_BLE_COEX_TAG, "REGISTER_APP_EVT, status %d, app_id %d\n", param->reg.status, param->reg.app_id);
        esp_ble_gap_config_local_privacy(true);
        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_A;
        //init BLE adv data and scan response data
        ble_init_adv_data(BLE_ADV_NAME);
        esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_A_APP_ID].service_id, GATTS_NUM_HANDLE_A);
        break;
    case ESP_GATTS_READ_EVT: {
        ESP_LOGI(BT_BLE_COEX_TAG, "GATT_READ_EVT, conn_id %d, trans_id %d, handle %d\n", 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(BT_BLE_COEX_TAG, "GATT_WRITE_EVT, conn_id %d, trans_id %d, handle %d", param->write.conn_id, param->write.trans_id, param->write.handle);
        if (!param->write.is_prep){
            ESP_LOGI(BT_BLE_COEX_TAG, "GATT_WRITE_EVT, value len %d, value :", param->write.len);
            esp_log_buffer_hex(BT_BLE_COEX_TAG, param->write.value, param->write.len);
            if (gl_profile_tab[PROFILE_A_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 (a_property & ESP_GATT_CHAR_PROP_BIT_NOTIFY){
                        ESP_LOGI(BT_BLE_COEX_TAG, "notify 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(BT_BLE_COEX_TAG, "indicate 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(BT_BLE_COEX_TAG, "notify/indicate disable ");
                }else{
                    ESP_LOGE(BT_BLE_COEX_TAG, "unknown descr value");
                    esp_log_buffer_hex(BT_BLE_COEX_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(BT_BLE_COEX_TAG,"ESP_GATTS_EXEC_WRITE_EVT");
        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(BT_BLE_COEX_TAG, "ESP_GATTS_MTU_EVT, MTU %d", param->mtu.mtu);
        break;
    case ESP_GATTS_UNREG_EVT:
        break;
    case ESP_GATTS_CREATE_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "CREATE_SERVICE_EVT, status %d,  service_handle %d\n", 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_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_initial_char_val, NULL);
        if (add_char_ret){
            ESP_LOGE(BT_BLE_COEX_TAG, "add char failed, error code = 0x%x",add_char_ret);
        }
        break;
    case ESP_GATTS_ADD_INCL_SRVC_EVT:
        break;
    case ESP_GATTS_ADD_CHAR_EVT: {
        ESP_LOGI(BT_BLE_COEX_TAG, "ADD_CHAR_EVT, status %d,  attr_handle %d, service_handle %d\n",
                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 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(BT_BLE_COEX_TAG, "add char descr failed, error code = 0x%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(BT_BLE_COEX_TAG, "ADD_DESCR_EVT, status %d, attr_handle %d, service_handle %d\n",
                 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(BT_BLE_COEX_TAG, "SERVICE_START_EVT, status %d, service_handle %d\n",
                 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));
        break;
    }
    case ESP_GATTS_DISCONNECT_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_GATTS_DISCONNECT_EVT");
        esp_ble_gap_start_advertising(&adv_params);
        break;
    case ESP_GATTS_CONF_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_GATTS_CONF_EVT, status %d", param->conf.status);
        if (param->conf.status != ESP_GATT_OK){
            esp_log_buffer_hex(BT_BLE_COEX_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(BT_BLE_COEX_TAG, "REGISTER_APP_EVT, status %d, app_id %d\n", param->reg.status, param->reg.app_id);
        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_B;

        esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_B_APP_ID].service_id, GATTS_NUM_HANDLE_B);
        break;
    case ESP_GATTS_READ_EVT: {
        ESP_LOGI(BT_BLE_COEX_TAG, "GATT_READ_EVT, conn_id %d, trans_id %d, handle %d\n", 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(BT_BLE_COEX_TAG, "GATT_WRITE_EVT, conn_id %d, trans_id %d, handle %d\n", param->write.conn_id, param->write.trans_id, param->write.handle);
        if (!param->write.is_prep){
            ESP_LOGI(BT_BLE_COEX_TAG, "GATT_WRITE_EVT, value len %d, value :", param->write.len);
            esp_log_buffer_hex(BT_BLE_COEX_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(BT_BLE_COEX_TAG, "notify 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(BT_BLE_COEX_TAG, "indicate 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(BT_BLE_COEX_TAG, "notify/indicate disable ");
                }else{
                    ESP_LOGE(BT_BLE_COEX_TAG, "unknown value");
                }

            }
        }
        example_write_event_env(gatts_if, &b_prepare_write_env, param);
        break;
    }
    case ESP_GATTS_EXEC_WRITE_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG,"ESP_GATTS_EXEC_WRITE_EVT");
        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(BT_BLE_COEX_TAG, "ESP_GATTS_MTU_EVT, MTU %d", param->mtu.mtu);
        break;
    case ESP_GATTS_UNREG_EVT:
        break;
    case ESP_GATTS_CREATE_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "CREATE_SERVICE_EVT, status %d,  service_handle %d\n", 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_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(BT_BLE_COEX_TAG, "add char failed, error code = 0x%x",add_char_ret);
        }
        break;
    case ESP_GATTS_ADD_INCL_SRVC_EVT:
        break;
    case ESP_GATTS_ADD_CHAR_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ADD_CHAR_EVT, status %d,  attr_handle %d, service_handle %d\n",
                 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(BT_BLE_COEX_TAG, "ADD_DESCR_EVT, status %d, attr_handle %d, service_handle %d\n",
                 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(BT_BLE_COEX_TAG, "SERVICE_START_EVT, status %d, service_handle %d\n",
                 param->start.status, param->start.service_handle);
        break;
    case ESP_GATTS_STOP_EVT:
        break;
    case ESP_GATTS_CONNECT_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "CONNECT_EVT, conn_id %d, remote %02x:%02x:%02x:%02x:%02x:%02x:",
                 param->connect.conn_id,
                 param->connect.remote_bda[0], param->connect.remote_bda[1], param->connect.remote_bda[2],
                 param->connect.remote_bda[3], param->connect.remote_bda[4], param->connect.remote_bda[5]);
        gl_profile_tab[PROFILE_B_APP_ID].conn_id = param->connect.conn_id;
        break;
    case ESP_GATTS_CONF_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_GATTS_CONF_EVT status %d", param->conf.status);
        if (param->conf.status != ESP_GATT_OK){
            esp_log_buffer_hex(BT_BLE_COEX_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(BT_BLE_COEX_TAG, "Reg app failed, app_id %04x, status %d\n",
                    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);
}

static void ble_gatts_init(void)
{
    esp_err_t ret = esp_ble_gatts_register_callback(gatts_event_handler);
    if (ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "gatts register error, error code = 0x%x", ret);
        return;
    }
    ret = esp_ble_gap_register_callback(gap_event_handler);
    if (ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "gap register error, error code = 0x%x", ret);
        return;
    }
    ret = esp_ble_gatts_app_register(PROFILE_A_APP_ID);
    if (ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "gatts app register error, error code = 0x%x", ret);
        return;
    }
    ret = esp_ble_gatts_app_register(PROFILE_B_APP_ID);
    if (ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "gatts app register error, error code = 0x%x", ret);
        return;
    }
    esp_err_t local_mtu_ret = esp_ble_gatt_set_local_mtu(500);
    if (local_mtu_ret){
        ESP_LOGE(BT_BLE_COEX_TAG, "set local  MTU failed, error code = 0x%x", local_mtu_ret);
    }
}

void bt_app_gap_cb(esp_bt_gap_cb_event_t event, esp_bt_gap_cb_param_t *param)
{
    switch (event) {
    case ESP_BT_GAP_AUTH_CMPL_EVT: {
        if (param->auth_cmpl.stat == ESP_BT_STATUS_SUCCESS) {
            ESP_LOGI(BT_BLE_COEX_TAG, "authentication success: %s", param->auth_cmpl.device_name);
            esp_log_buffer_hex(BT_BLE_COEX_TAG, param->auth_cmpl.bda, ESP_BD_ADDR_LEN);
        } else {
            ESP_LOGE(BT_BLE_COEX_TAG, "authentication failed, status:%d", param->auth_cmpl.stat);
        }
        break;
    }
#if (CONFIG_BT_SSP_ENABLED == true)
    case ESP_BT_GAP_CFM_REQ_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_BT_GAP_CFM_REQ_EVT Please compare the numeric value: %d", param->cfm_req.num_val);
        esp_bt_gap_ssp_confirm_reply(param->cfm_req.bda, true);
        break;
    case ESP_BT_GAP_KEY_NOTIF_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_BT_GAP_KEY_NOTIF_EVT passkey:%d", param->key_notif.passkey);
        break;
    case ESP_BT_GAP_KEY_REQ_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_BT_GAP_KEY_REQ_EVT Please enter passkey!");
        break;
#endif
    case ESP_BT_GAP_MODE_CHG_EVT:
        ESP_LOGI(BT_BLE_COEX_TAG, "ESP_BT_GAP_MODE_CHG_EVT mode:%d", param->mode_chg.mode);
        break;

    default: {
        ESP_LOGI(BT_BLE_COEX_TAG, "event: %d", event);
        break;
    }
    }
    return;
}

/* handler for bluetooth stack enabled events */
static void bt_av_hdl_stack_evt(uint16_t event, void *p_param)
{
    ESP_LOGD(BT_BLE_COEX_TAG, "%s evt %d", __func__, event);
    switch (event) {
    case BT_APP_EVT_STACK_UP: {
        /* set up bt device name */
        esp_bt_dev_set_device_name(BT_DEVICE_NAME);

        esp_bt_gap_register_callback(bt_app_gap_cb);

        /* initialize AVRCP controller */
        esp_avrc_ct_init();
        esp_avrc_ct_register_callback(bt_app_rc_ct_cb);
        /* initialize AVRCP target */
        assert (esp_avrc_tg_init() == ESP_OK);
        esp_avrc_tg_register_callback(bt_app_rc_tg_cb);

        esp_avrc_rn_evt_cap_mask_t evt_set = {0};
        esp_avrc_rn_evt_bit_mask_operation(ESP_AVRC_BIT_MASK_OP_SET, &evt_set, ESP_AVRC_RN_VOLUME_CHANGE);
        assert(esp_avrc_tg_set_rn_evt_cap(&evt_set) == ESP_OK);

        /* initialize A2DP sink */
        esp_a2d_register_callback(&bt_app_a2d_cb);
        esp_a2d_sink_register_data_callback(bt_app_a2d_data_cb);
        esp_a2d_sink_init();

        /* set discoverable and connectable mode, wait to be connected */
        esp_bt_gap_set_scan_mode(ESP_BT_CONNECTABLE, ESP_BT_GENERAL_DISCOVERABLE);
        break;
    }
    default:
        ESP_LOGE(BT_BLE_COEX_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

void app_main(void)
{
    /* Initialize NVS — it is used to store PHY calibration data */
    esp_err_t err = nvs_flash_init();
    if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        ESP_ERROR_CHECK(nvs_flash_erase());
        err = nvs_flash_init();
    }
    ESP_ERROR_CHECK(err);

#ifdef CONFIG_EXAMPLE_A2DP_SINK_OUTPUT_INTERNAL_DAC
    dac_conti_config_t conti_cfg = {
        .chan_mask = DAC_CHANNEL_MASK_ALL,
        .desc_num = 8,
        .buf_size = 2048,
        .freq_hz = 44100,
        .offset = 127,
        .clk_src = DAC_DIGI_CLK_SRC_DEFAULT,   // Using APLL as clock source to get a wider frequency range
        .chan_mode = DAC_CHANNEL_MODE_ALTER,
    };
    /* Allocate continuous channels */
    ESP_ERROR_CHECK(dac_new_conti_channels(&conti_cfg, &tx_chan));
    /* Enable the continuous channels */
    ESP_ERROR_CHECK(dac_conti_enable(tx_chan));
#else
    i2s_chan_config_t chan_cfg = I2S_CHANNEL_DEFAULT_CONFIG(I2S_NUM_0, I2S_ROLE_MASTER);
    chan_cfg.auto_clear = true;
    i2s_std_config_t std_cfg = {
        .clk_cfg = I2S_STD_CLK_DEFAULT_CONFIG(44100),
        .slot_cfg = I2S_STD_MSB_SLOT_DEFAULT_CONFIG(I2S_DATA_BIT_WIDTH_16BIT, I2S_SLOT_MODE_STEREO),
        .gpio_cfg = {
            .mclk = I2S_GPIO_UNUSED,
            .bclk = CONFIG_EXAMPLE_I2S_BCK_PIN,
            .ws = CONFIG_EXAMPLE_I2S_LRCK_PIN,
            .dout = CONFIG_EXAMPLE_I2S_DATA_PIN,
            .din = I2S_GPIO_UNUSED,
            .invert_flags = {
                .mclk_inv = false,
                .bclk_inv = false,
                .ws_inv = false,
            },
        },
    };
    /* enable I2S */
    ESP_ERROR_CHECK(i2s_new_channel(&chan_cfg, &tx_chan, NULL));
    ESP_ERROR_CHECK(i2s_channel_init_std_mode(tx_chan, &std_cfg));
    ESP_ERROR_CHECK(i2s_channel_enable(tx_chan));
#endif

    esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
    if ((err = esp_bt_controller_init(&bt_cfg)) != ESP_OK) {
        ESP_LOGE(BT_BLE_COEX_TAG, "%s initialize controller failed: %s\n", __func__, esp_err_to_name(err));
        return;
    }

    if ((err = esp_bt_controller_enable(ESP_BT_MODE_BTDM)) != ESP_OK) {
        ESP_LOGE(BT_BLE_COEX_TAG, "%s enable controller failed: %s\n", __func__, esp_err_to_name(err));
        return;
    }

    if ((err = esp_bluedroid_init()) != ESP_OK) {
        ESP_LOGE(BT_BLE_COEX_TAG, "%s initialize bluedroid failed: %s\n", __func__, esp_err_to_name(err));
        return;
    }

    if ((err = esp_bluedroid_enable()) != ESP_OK) {
        ESP_LOGE(BT_BLE_COEX_TAG, "%s enable bluedroid failed: %s\n", __func__, esp_err_to_name(err));
        return;
    }

    /* create application task */
    bt_app_task_start_up();

    /* Bluetooth device name, connection mode and profile set up */
    bt_app_work_dispatch(bt_av_hdl_stack_evt, BT_APP_EVT_STACK_UP, NULL, 0, NULL);

#if (CONFIG_BT_SSP_ENABLED == true)
    /* Set default parameters for Secure Simple Pairing */
    esp_bt_sp_param_t param_type = ESP_BT_SP_IOCAP_MODE;
    esp_bt_io_cap_t iocap = ESP_BT_IO_CAP_IO;
    esp_bt_gap_set_security_param(param_type, &iocap, sizeof(uint8_t));
#endif

    /*
     * Set default parameters for Legacy Pairing
     * Use fixed pin code
     */
    esp_bt_pin_type_t pin_type = ESP_BT_PIN_TYPE_FIXED;
    esp_bt_pin_code_t pin_code;
    pin_code[0] = '1';
    pin_code[1] = '2';
    pin_code[2] = '3';
    pin_code[3] = '4';
    esp_bt_gap_set_pin(pin_type, 4, pin_code);

    //gatt server init
    ble_gatts_init();
}