/*
 * SPDX-FileCopyrightText: 2017-2022 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#pragma once

#include <esp_http_client.h>
#include <bootloader_common.h>
#include "esp_app_desc.h"
#include <sdkconfig.h>

#include "esp_event.h"
#include "esp_partition.h"

#ifdef __cplusplus
extern "C" {
#endif

ESP_EVENT_DECLARE_BASE(ESP_HTTPS_OTA_EVENT);

/**
 * @brief   Events generated by OTA process
 */
typedef enum {
    ESP_HTTPS_OTA_START,                    /*!< OTA started */
    ESP_HTTPS_OTA_CONNECTED,                /*!< Connected to server */
    ESP_HTTPS_OTA_GET_IMG_DESC,             /*!< Read app description from image header */
    ESP_HTTPS_OTA_VERIFY_CHIP_ID,           /*!< Verify chip id of new image */
    ESP_HTTPS_OTA_DECRYPT_CB,               /*!< Callback to decrypt function */
    ESP_HTTPS_OTA_WRITE_FLASH,              /*!< Flash write operation */
    ESP_HTTPS_OTA_UPDATE_BOOT_PARTITION,    /*!< Boot partition update after successful ota update */
    ESP_HTTPS_OTA_FINISH,                   /*!< OTA finished */
    ESP_HTTPS_OTA_ABORT,                    /*!< OTA aborted */
} esp_https_ota_event_t;


typedef void *esp_https_ota_handle_t;
typedef esp_err_t(*http_client_init_cb_t)(esp_http_client_handle_t);

#if CONFIG_ESP_HTTPS_OTA_DECRYPT_CB
typedef struct {
    const char *data_in;    /*!< Pointer to data to be decrypted */
    size_t data_in_len;     /*!< Input data length */
    char *data_out;         /*!< Pointer to data decrypted using callback, this will be freed after data is written to flash */
    size_t data_out_len;    /*!< Output data length */
} decrypt_cb_arg_t;

typedef esp_err_t(*decrypt_cb_t)(decrypt_cb_arg_t *args, void *user_ctx);
#endif // CONFIG_ESP_HTTPS_OTA_DECRYPT_CB

/**
 * @brief ESP HTTPS OTA configuration
 */
typedef struct {
    const esp_http_client_config_t *http_config;   /*!< ESP HTTP client configuration */
    http_client_init_cb_t http_client_init_cb;     /*!< Callback after ESP HTTP client is initialised */
    bool bulk_flash_erase;                         /*!< Erase entire flash partition during initialization. By default flash partition is erased during write operation and in chunk of 4K sector size */
    bool partial_http_download;                    /*!< Enable Firmware image to be downloaded over multiple HTTP requests */
    int max_http_request_size;                     /*!< Maximum request size for partial HTTP download */
#if CONFIG_ESP_HTTPS_OTA_DECRYPT_CB
    decrypt_cb_t decrypt_cb;                       /*!< Callback for external decryption layer */
    void *decrypt_user_ctx;                        /*!< User context for external decryption layer */
    uint16_t enc_img_header_size;                  /*!< Header size of pre-encrypted ota image header */
#endif
} esp_https_ota_config_t;

#define ESP_ERR_HTTPS_OTA_BASE            (0x9000)
#define ESP_ERR_HTTPS_OTA_IN_PROGRESS     (ESP_ERR_HTTPS_OTA_BASE + 1)  /* OTA operation in progress */

/**
 * @brief    HTTPS OTA Firmware upgrade.
 *
 * This function allocates HTTPS OTA Firmware upgrade context, establishes HTTPS connection,
 * reads image data from HTTP stream and writes it to OTA partition and
 * finishes HTTPS OTA Firmware upgrade operation.
 * This API supports URL redirection, but if CA cert of URLs differ then it
 * should be appended to `cert_pem` member of `ota_config->http_config`.
 *
 * @param[in]  ota_config       pointer to esp_https_ota_config_t structure.
 *
 * @note     This API handles the entire OTA operation, so if this API is being used
 *           then no other APIs from `esp_https_ota` component should be called.
 *           If more information and control is needed during the HTTPS OTA process,
 *           then one can use `esp_https_ota_begin` and subsequent APIs. If this API returns
 *           successfully, esp_restart() must be called to boot from the new firmware image.
 *
 * @return
 *    - ESP_OK: OTA data updated, next reboot will use specified partition.
 *    - ESP_FAIL: For generic failure.
 *    - ESP_ERR_INVALID_ARG: Invalid argument
 *    - ESP_ERR_OTA_VALIDATE_FAILED: Invalid app image
 *    - ESP_ERR_NO_MEM: Cannot allocate memory for OTA operation.
 *    - ESP_ERR_FLASH_OP_TIMEOUT or ESP_ERR_FLASH_OP_FAIL: Flash write failed.
 *    - For other return codes, refer OTA documentation in esp-idf's app_update component.
 */
esp_err_t esp_https_ota(const esp_https_ota_config_t *ota_config);

/**
 * @brief    Start HTTPS OTA Firmware upgrade
 *
 * This function initializes ESP HTTPS OTA context and establishes HTTPS connection.
 * This function must be invoked first. If this function returns successfully, then `esp_https_ota_perform` should be
 * called to continue with the OTA process and there should be a call to `esp_https_ota_finish` on
 * completion of OTA operation or on failure in subsequent operations.
 * This API supports URL redirection, but if CA cert of URLs differ then it
 * should be appended to `cert_pem` member of `http_config`, which is a part of `ota_config`.
 * In case of error, this API explicitly sets `handle` to NULL.
 *
 * @param[in]   ota_config       pointer to esp_https_ota_config_t structure
 * @param[out]  handle           pointer to an allocated data of type `esp_https_ota_handle_t`
 *                               which will be initialised in this function
 *
 * @note     This API is blocking, so setting `is_async` member of `http_config` structure will
 *           result in an error.
 *
 * @return
 *    - ESP_OK: HTTPS OTA Firmware upgrade context initialised and HTTPS connection established
 *    - ESP_FAIL: For generic failure.
 *    - ESP_ERR_INVALID_ARG: Invalid argument (missing/incorrect config, certificate, etc.)
 *    - For other return codes, refer documentation in app_update component and esp_http_client
 *      component in esp-idf.
 */
esp_err_t esp_https_ota_begin(const esp_https_ota_config_t *ota_config, esp_https_ota_handle_t *handle);

/**
 * @brief    Read image data from HTTP stream and write it to OTA partition
 *
 * This function reads image data from HTTP stream and writes it to OTA partition. This function
 * must be called only if esp_https_ota_begin() returns successfully.
 * This function must be called in a loop since it returns after every HTTP read operation thus
 * giving you the flexibility to stop OTA operation midway.
 *
 * @param[in]  https_ota_handle  pointer to esp_https_ota_handle_t structure
 *
 * @return
 *    - ESP_ERR_HTTPS_OTA_IN_PROGRESS: OTA update is in progress, call this API again to continue.
 *    - ESP_OK: OTA update was successful
 *    - ESP_FAIL: OTA update failed
 *    - ESP_ERR_INVALID_ARG: Invalid argument
 *    - ESP_ERR_INVALID_VERSION: Invalid chip revision in image header
 *    - ESP_ERR_OTA_VALIDATE_FAILED: Invalid app image
 *    - ESP_ERR_NO_MEM: Cannot allocate memory for OTA operation.
 *    - ESP_ERR_FLASH_OP_TIMEOUT or ESP_ERR_FLASH_OP_FAIL: Flash write failed.
 *    - For other return codes, refer OTA documentation in esp-idf's app_update component.
 */
esp_err_t esp_https_ota_perform(esp_https_ota_handle_t https_ota_handle);

/**
 * @brief   Checks if complete data was received or not
 *
 * @note    This API can be called just before esp_https_ota_finish() to validate if the complete image was indeed received.
 *
 * @param[in]   https_ota_handle pointer to esp_https_ota_handle_t structure
 *
 * @return
 *    - false
 *    - true
 */
bool esp_https_ota_is_complete_data_received(esp_https_ota_handle_t https_ota_handle);

/**
 * @brief    Clean-up HTTPS OTA Firmware upgrade and close HTTPS connection
 *
 * This function closes the HTTP connection and frees the ESP HTTPS OTA context.
 * This function switches the boot partition to the OTA partition containing the
 * new firmware image.
 *
 * @note     If this API returns successfully, esp_restart() must be called to
 *           boot from the new firmware image
 *           esp_https_ota_finish should not be called after calling esp_https_ota_abort
 *
 * @param[in]  https_ota_handle   pointer to esp_https_ota_handle_t structure
 *
 * @return
 *    - ESP_OK: Clean-up successful
 *    - ESP_ERR_INVALID_STATE
 *    - ESP_ERR_INVALID_ARG: Invalid argument
 *    - ESP_ERR_OTA_VALIDATE_FAILED: Invalid app image
 */
esp_err_t esp_https_ota_finish(esp_https_ota_handle_t https_ota_handle);


/**
 * @brief Clean-up HTTPS OTA Firmware upgrade and close HTTPS connection
 *
 * This function closes the HTTP connection and frees the ESP HTTPS OTA context.
 *
 * @note     esp_https_ota_abort should not be called after calling esp_https_ota_finish
 *
 * @param[in]  https_ota_handle   pointer to esp_https_ota_handle_t structure
 *
 * @return
 *    - ESP_OK: Clean-up successful
 *    - ESP_ERR_INVALID_STATE: Invalid ESP HTTPS OTA state
 *    - ESP_FAIL: OTA not started
 *    - ESP_ERR_NOT_FOUND: OTA handle not found
 *    - ESP_ERR_INVALID_ARG: Invalid argument
 */
esp_err_t esp_https_ota_abort(esp_https_ota_handle_t https_ota_handle);


/**
 * @brief   Reads app description from image header. The app description provides information
 *          like the "Firmware version" of the image.
 *
 * @note    This API can be called only after esp_https_ota_begin() and before esp_https_ota_perform().
 *          Calling this API is not mandatory.
 *
 * @param[in]   https_ota_handle   pointer to esp_https_ota_handle_t structure
 * @param[out]  new_app_info       pointer to an allocated esp_app_desc_t structure
 *
 * @return
 *    - ESP_ERR_INVALID_ARG: Invalid arguments
 *    - ESP_ERR_INVALID_STATE: Invalid state to call this API. esp_https_ota_begin() not called yet.
 *    - ESP_FAIL: Failed to read image descriptor
 *    - ESP_OK: Successfully read image descriptor
 */
esp_err_t esp_https_ota_get_img_desc(esp_https_ota_handle_t https_ota_handle, esp_app_desc_t *new_app_info);


/**
* @brief  This function returns OTA image data read so far.
*
* @note   This API should be called only if `esp_https_ota_perform()` has been called atleast once or
*         if `esp_https_ota_get_img_desc` has been called before.
*
* @param[in]   https_ota_handle   pointer to esp_https_ota_handle_t structure
*
* @return
*    - -1    On failure
*    - total bytes read so far
*/
int esp_https_ota_get_image_len_read(esp_https_ota_handle_t https_ota_handle);


/**
 * @brief  This function returns the HTTP status code of the last HTTP response.
 *
 * @note   This API should be called only after esp_https_ota_begin() has been called.
 *         This can be used to check the HTTP status code of the OTA download process.
 *
 * @param[in]   https_ota_handle   pointer to esp_https_ota_handle_t structure
 *
 * @return
 *    - -1    On failure
 *    - HTTP status code
 */
int esp_https_ota_get_status_code(esp_https_ota_handle_t https_ota_handle);


/**
* @brief  This function returns OTA image total size.
*
* @note   This API should be called after esp_https_ota_begin() has been already called.
*         This can be used to create some sort of progress indication
*         (in combination with esp_https_ota_get_image_len_read())
*
* @param[in]   https_ota_handle   pointer to esp_https_ota_handle_t structure
*
* @return
*    - -1    On failure or chunked encoding
*    - total bytes of image
*/
int esp_https_ota_get_image_size(esp_https_ota_handle_t https_ota_handle);
#ifdef __cplusplus
}
#endif
