/*
 * challenge_nvs.c
 *
 *  Created on: 08.12.2022
 *      Author: jonas
 */

#include "challenge_nvs.h"
#include "esp_log.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "nvs.h"

/* defines / constants */
#define TAG "CHALLENGE_NVS" /* tag for logging with ESP_LOG */
const char* NAMESPACE_NVS = "storage";
const char* ROBOT_MODE_KEY = "robot_mode";

/* local vars */
bool initializedSuccessfully = false;

/*! \brief Initialize the NVS storage. */
void Challenge_Nvs_Init(void){
	ESP_LOGI(TAG, "Initializing...");

	// Initialize NVS
	esp_err_t err = nvs_flash_init();
	if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
		// NVS partition was truncated and needs to be erased
		// Retry nvs_flash_init
		ESP_ERROR_CHECK(nvs_flash_erase());
		err = nvs_flash_init();
	}
	ESP_ERROR_CHECK( err );
	initializedSuccessfully = (err == ESP_OK);

	ESP_LOGI(TAG, "Initialized. Success=%s", initializedSuccessfully?"true":"false");
}

/*! \brief Deinitialize the NVS storage. */
void Challenge_Nvs_Deinit(void){
	ESP_LOGI(TAG, "Deinitializing...");
	esp_err_t err = nvs_flash_deinit();
	ESP_LOGI(TAG, "Deinitialized. Success=%s", err==ESP_OK?"true":"false");
}

/*!
* \brief Stores the passed robot mode in NVS.
* \param modeStationary Mode to store. True = stationary mode, False = mobile mode
* \return true on success
*/
bool Challenge_Nvs_StoreRobotModeToNVS(bool mode){
	bool success = false;

	// Open
	ESP_LOGI(TAG, "Opening Non-Volatile Storage (NVS) handle... ");
	nvs_handle_t my_handle;
	esp_err_t err = nvs_open(NAMESPACE_NVS, NVS_READWRITE, &my_handle);
	if (err != ESP_OK) {
		ESP_LOGE(TAG, "Error (%s) opening NVS handle!\n", esp_err_to_name(err));
		return false;
	}

	// Write
	uint8_t value = mode?1:0;
	ESP_LOGI(TAG, "Updating robotMode in NVS ... ");
	err = nvs_set_u8(my_handle, ROBOT_MODE_KEY, value);
	if(err != ESP_OK){
		ESP_LOGE(TAG, "Failed to update robotMode in NVS. Error=(%s)", esp_err_to_name(err));
		success = false;
	}else{ // successfully set
		// Commit written value.
		// After setting any values, nvs_commit() must be called to ensure changes are written
		// to flash storage. Implementations may write to storage at other times,
		// but this is not guaranteed.
		ESP_LOGI(TAG, "Committing updates in NVS ... ");
		err = nvs_commit(my_handle);
		if(err != ESP_OK){
			ESP_LOGE(TAG, "Failed to commit to NVS. Error=(%s)", esp_err_to_name(err));
			success = false;
		}else{
			ESP_LOGI(TAG, "Successfully committed changes to NVS.");
			success = true;
		}
	}

	// Close
	nvs_close(my_handle);

	return success;
}

/*!
 * \brief Retrieve the robot mode stored in NVS.
 * \param mode Pointer to the location where to retrieve the mode to. True = stationary mode, False = mobile mode
 * \return true on success
 */
bool Challenge_Nvs_GetRobotModeFromNVS(bool *mode){
	bool success = false;
	bool notInitialized = false;

    // Open
    ESP_LOGI(TAG, "Opening Non-Volatile Storage (NVS) handle... ");
    nvs_handle_t my_handle;
    esp_err_t err = nvs_open(NAMESPACE_NVS, NVS_READWRITE, &my_handle);
    if (err != ESP_OK) {
    	ESP_LOGE(TAG, "Error (%s) opening NVS handle!\n", esp_err_to_name(err));
    	return false;
    }

    // Read
    ESP_LOGI(TAG, "Reading robot mode from NVS ... ");
    uint8_t value = 0;
	err = nvs_get_u8(my_handle, ROBOT_MODE_KEY, &value);
	switch (err) {
		case ESP_OK:
			ESP_LOGI(TAG, "Reading robot mode done. Read robotMode = %i", value);
			*mode = (bool)(value==1?true:false); // set value at pointer location
			success = true;
			break;
		case ESP_ERR_NVS_NOT_FOUND:
			ESP_LOGI(TAG, "Reading robot mode done. The value is not initialized yet!");
			notInitialized = true;
			break;
		default :
			ESP_LOGI(TAG, "Error reading robot mode. Error=(%s)", esp_err_to_name(err));
			success = false;
	}

	// Close
	nvs_close(my_handle);

	if(notInitialized){
		success = Challenge_Nvs_StoreRobotModeToNVS(false);  // initialize to false
	}

	return success;
}