text: // Copyright 2020 Espressif Systems (Shanghai) Co. Ltd.
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  #ifndef _BUTTON_H_
  #define _BUTTON_H_
  
  #include "button_adc.h"
  #include "button_gpio.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  typedef void (* button_cb_t)(void *);
  typedef void *button_handle_t;
  
  /**
   * @brief Button events
   *
   */
  typedef enum {
      BUTTON_PRESS_DOWN = 0,
      BUTTON_PRESS_UP,
      BUTTON_PRESS_REPEAT,
      BUTTON_SINGLE_CLICK,
      BUTTON_DOUBLE_CLICK,
      BUTTON_LONG_PRESS_START,
      BUTTON_LONG_PRESS_HOLD,
      BUTTON_EVENT_MAX,
      BUTTON_NONE_PRESS,
  } button_event_t;
  
  /**
   * @brief Supported button type
   *
   */
  typedef enum {
      BUTTON_TYPE_GPIO,
      BUTTON_TYPE_ADC,
  } button_type_t;
  
  /**
   * @brief Button configuration
   *
   */
  typedef struct {
      button_type_t type;                           /**< button type, The corresponding button configuration must be filled */
      union {
          button_gpio_config_t gpio_button_config; /**< gpio button configuration */
          button_adc_config_t adc_button_config;   /**< adc button configuration */
      }; /**< button configuration */
  } button_config_t;
  
  typedef struct Button {
      uint16_t        ticks;
      uint8_t         repeat;
      button_event_t  event;
      uint8_t         state: 3;
      uint8_t         debounce_cnt: 3;
      uint8_t         active_level: 1;
      uint8_t         button_level: 1;
      uint8_t         (*hal_button_Level)(void *usr_data);
      void            *usr_data;
      button_type_t   type;
      button_cb_t     cb[BUTTON_EVENT_MAX];
      void            *cb_user_data;
      struct Button   *next;
  } button_dev_t;
  
  /**
   * @brief Create a button
   *
   * @param config pointer of button configuration, must corresponding the button type
   *
   * @return A handle to the created button, or NULL in case of error.
   */
  button_handle_t button_create(const button_config_t *config);
  
  /**
   * @brief Delete a button
   *
   * @param btn_handle A button handle to delete
   *
   * @return
   *      - ESP_OK  Success
   *      - ESP_FAIL Failure
   */
  esp_err_t button_delete(button_handle_t btn_handle);
  
  /**
   * @brief Register the button event callback function.
   *
   * @param btn_handle A button handle to register
   * @param event Button event
   * @param cb Callback function.
   *
   * @return
   *      - ESP_OK on success
   *      - ESP_ERR_INVALID_ARG   Arguments is invalid.
   */
  esp_err_t button_register_cb(button_handle_t btn_handle, button_event_t event, button_cb_t cb);
  
  /**
   * @brief Unregister the button event callback function.
   *
   * @param btn_handle A button handle to unregister
   * @param event Button event
   *
   * @return
   *      - ESP_OK on success
   *      - ESP_ERR_INVALID_ARG   Arguments is invalid.
   */
  esp_err_t button_unregister_cb(button_handle_t btn_handle, button_event_t event);
  
  /**
   * @brief Get button event
   *
   * @param btn_handle Button handle
   *
   * @return Current button event. See button_event_t
   */
  button_event_t button_get_event(button_handle_t btn_handle);
  
  /**
   * @brief Get button repeat times
   *
   * @param btn_handle Button handle
   *
   * @return button pressed times. For example, double-click return 2, triple-click return 3, etc.
   */
  uint8_t button_get_repeat(button_handle_t btn_handle);
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif
  