text: #ifndef APP_SETTINGS_H
  #define APP_SETTINGS_H
  
  typedef enum {
  	SETTINGS_WIFI_SSID,
  	SETTINGS_WIFI_PASSWD,
  	SETTINGS_AP_SSID,
  	SETTINGS_AP_IP_ADDR,
  	SETTINGS_MQTT_CLIENT_HOST_ADDR,
  	SETTINGS_MQTT_CLIENT_PORT,
  	SETTINGS_ROOT_CA_PEM,
  	SETTINGS_CERT_PEM,
  	SETTIGNS_PRIV_KEY
  } app_settings_json_token_t;
  
  esp_err_t app_settings_read(char *buf, size_t buflen);
  esp_err_t app_settings_init(void);
  esp_err_t app_settings_get_value(app_settings_json_token_t t, char *out_buf);
  void *app_settings_get_value_p(app_settings_json_token_t t, size_t *size);
  esp_err_t app_settings_get_multiline(app_settings_json_token_t t, char *out_buf);
  esp_err_t app_settings_get_linefeeded_string(app_settings_json_token_t t, char *out_buf);
  
  #endif /* APP_SETTINGS_H */
  