#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stm32l0xx_hal.h>
#include <stdbool.h>

#define VCP_TX_Pin GPIO_PIN_2
#define VCP_TX_GPIO_Port GPIOA
#define STCP_Pin GPIO_PIN_4
#define STCP_GPIO_Port GPIOA
#define SHCP_Pin GPIO_PIN_5
#define SHCP_GPIO_Port GPIOA
#define DS_Pin GPIO_PIN_7
#define DS_GPIO_Port GPIOA
#define TMS_Pin GPIO_PIN_13
#define TMS_GPIO_Port GPIOA
#define TCK_Pin GPIO_PIN_14
#define TCK_GPIO_Port GPIOA
#define VCP_RX_Pin GPIO_PIN_15
#define VCP_RX_GPIO_Port GPIOA
#define LD3_Pin GPIO_PIN_3
#define LD3_GPIO_Port GPIOB

UART_HandleTypeDef huart2;

void SystemClock_Config(void);
static void MX_USART2_UART_Init(void);
static void MX_GPIO_Init(void);

bool DS_State[8];
uint8_t Temp;
uint8_t Count;

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_USART2_UART_Init();

  HAL_Delay(1000);
  printf("Hello, %s!\n", "Wokwi");

  HAL_GPIO_WritePin(DS_GPIO_Port,DS_Pin,GPIO_PIN_RESET);
  HAL_GPIO_WritePin(SHCP_GPIO_Port,SHCP_Pin,GPIO_PIN_SET);
  HAL_GPIO_WritePin(STCP_GPIO_Port,STCP_Pin,GPIO_PIN_SET);

  for(int i=0;i<8;i++)
  {
    HAL_GPIO_WritePin(DS_GPIO_Port,DS_Pin,DS_State[7-i]);
    HAL_GPIO_WritePin(SHCP_GPIO_Port,SHCP_Pin,GPIO_PIN_RESET);
    HAL_GPIO_WritePin(SHCP_GPIO_Port,SHCP_Pin,GPIO_PIN_SET);
  }
  HAL_GPIO_WritePin(STCP_GPIO_Port,STCP_Pin,GPIO_PIN_RESET);
  HAL_GPIO_WritePin(STCP_GPIO_Port,STCP_Pin,GPIO_PIN_SET);

  while (1)
  {
  //   HAL_GPIO_TogglePin(DS_GPIO_Port,DS_Pin);
    Temp = 0;
    Temp = 1 << Count;
    DS_State[0] = Temp & 0x01;
    DS_State[1] = Temp & 0x02;
    DS_State[2] = Temp & 0x04;
    DS_State[3] = Temp & 0x08;
    DS_State[4] = Temp & 0x10;
    DS_State[5] = Temp & 0x20;
    DS_State[6] = Temp & 0x40;
    DS_State[7] = Temp & 0x80;
    for(int i=0;i<8;i++)
    {
      HAL_GPIO_WritePin(DS_GPIO_Port,DS_Pin,DS_State[7-i]);
      HAL_GPIO_WritePin(SHCP_GPIO_Port,SHCP_Pin,GPIO_PIN_RESET);
      HAL_GPIO_WritePin(SHCP_GPIO_Port,SHCP_Pin,GPIO_PIN_SET);
    }
    HAL_GPIO_WritePin(STCP_GPIO_Port,STCP_Pin,GPIO_PIN_RESET);
    HAL_GPIO_WritePin(STCP_GPIO_Port,STCP_Pin,GPIO_PIN_SET);
      Count++;
      if(Count > 7)Count = 0;
      HAL_Delay(100);
    }

  return 0;
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART2;
  PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
  huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_Init 2 */

}

static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, STCP_Pin|SHCP_Pin|DS_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LD3_GPIO_Port, LD3_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pins : STCP_Pin SHCP_Pin DS_Pin */
  GPIO_InitStruct.Pin = STCP_Pin|SHCP_Pin|DS_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : LD3_Pin */
  GPIO_InitStruct.Pin = LD3_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LD3_GPIO_Port, &GPIO_InitStruct);

}

void Error_Handler(void)
{
  /* User can add his own implementation to report the HAL error return state */
}


// The following makes printf() write to USART2:

#define STDOUT_FILENO   1
#define STDERR_FILENO   2

int _write(int file, uint8_t *ptr, int len)
{
  switch (file)
  {
    case STDOUT_FILENO:
      HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
      break;

    case STDERR_FILENO:
      HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
      break;

    default:
      return -1;
  }

  return len;
}