#include "common/constants.h"
#include "io/nvs_handler.h"
#include "nvs_flash.h"

NVSStorageHandler::~NVSStorageHandler() {
  if (this->nvsHandle != 0) {
    nvs_close(this->nvsHandle);
    this->nvsHandle = 0;
  }
}

void NVSStorageHandler::init(const EventGroupHandle_t& system_event_group) {
  esp_err_t err = nvs_flash_init();
  if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
    nvs_flash_erase();
    err = nvs_flash_init();
  }
  ESP_ERROR_CHECK(err);

  err = nvs_open("storage", NVS_READWRITE, &this->nvsHandle);
  if (err != ESP_OK) {
    printf("Error (%s) opening NVS handle!\n", esp_err_to_name(err));
  } else {
    xEventGroupSetBits(system_event_group, STORAGE_READY_BIT);
    printf("NVS Storage initialized.\n");
  }
}

void NVSStorageHandler::put(const char*& key, const char*& value) {
  if (this->nvsHandle == 0) {
    printf("NVS handle is not initialized.\n");
    return;
  }

  esp_err_t err = nvs_set_str(this->nvsHandle, key, value);
  if (err != ESP_OK) {
    printf("Error (%s) setting key-value pair in NVS!\n", esp_err_to_name(err));
  } else {
    nvs_commit(this->nvsHandle);
    printf("Key-value pair (%s, %s) stored in NVS.\n", key, value);
  }
}

char* NVSStorageHandler::get(const char*& key) const {
  if (this->nvsHandle == 0) {
    printf("NVS handle is not initialized.\n");
    return nullptr;
  }

  size_t required_size = 0;
  esp_err_t err = nvs_get_str(this->nvsHandle, key, nullptr, &required_size);
  if (err == ESP_ERR_NVS_NOT_FOUND) {
    printf("Key %s not found in NVS.\n", key);
    return nullptr;
  } else if (err != ESP_OK) {
    printf("Error (%s) getting size for key %s from NVS!\n", esp_err_to_name(err), key);
    return nullptr;
  }

  char* value = (char*)malloc(required_size);
  err = nvs_get_str(this->nvsHandle, key, value, &required_size);
  if (err != ESP_OK) {
    printf("Error (%s) getting value for key %s from NVS!\n", esp_err_to_name(err), key);
    free(value);
    return nullptr;
  }

  return value;
}

void NVSStorageHandler::remove(const char*& key) {
  if (this->nvsHandle == 0) {
    printf("NVS handle is not initialized.\n");
    return;
  }

  esp_err_t err = nvs_erase_key(this->nvsHandle, key);
  if (err != ESP_OK) {
    printf("Error (%s) deleting key %s from NVS!\n", esp_err_to_name(err), key);
  } else {
    nvs_commit(this->nvsHandle);
    printf("Key %s deleted from NVS.\n", key);
  }
}