#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stm32l0xx_hal.h>
#define VCP_TX_Pin GPIO_PIN_2
#define VCP_RX_Pin GPIO_PIN_15
#define STDOUT_FILENO   1
#define STDERR_FILENO   2
static void UART_Init(void);
UART_HandleTypeDef huart2;
#define OLED_Width 128
uint8_t OLED_buffer[8][128]; 
uint8_t OLED_buffer_flag[128];
I2C_HandleTypeDef hi2c1;
int main(void) {
  HAL_Init();
  SystemClock_Config();
  GPIO_Init();
  I2C_Init();
  UART_Init();
  printf("Hello, %s!\n", "Wokwi");
  HAL_Delay(1000);
		LCD_Init();

  while (1) {
  
  }
}

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_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLLMUL_4;
  RCC_OscInitStruct.PLL.PLLDIV = RCC_PLLDIV_2;
  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_PLLCLK;
  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_1) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART2;
  PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
}

void GPIO_Init() {
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_I2C1_CLK_ENABLE();

  GPIO_InitTypeDef IIC_Config = {0};
  IIC_Config.Mode             = GPIO_MODE_AF_OD;
  IIC_Config.Pull             = GPIO_NOPULL ;
  IIC_Config.Pin              = GPIO_PIN_7 | GPIO_PIN_6;
  IIC_Config.Speed            = GPIO_SPEED_FREQ_HIGH;
  IIC_Config.Alternate        = GPIO_AF1_I2C1;
  HAL_GPIO_Init(GPIOB, &IIC_Config);

  GPIO_InitTypeDef UART_Config = {0};
  UART_Config.Pin              = VCP_TX_Pin | VCP_RX_Pin;
  UART_Config.Mode             = GPIO_MODE_AF_PP;
  UART_Config.Pull             = GPIO_NOPULL;
  UART_Config.Speed            = GPIO_SPEED_FREQ_LOW;
  UART_Config.Alternate        = GPIO_AF4_USART2;
  HAL_GPIO_Init(GPIOA, &UART_Config);
}

void I2C_Init() {

  hi2c1.Instance              = I2C1;
  hi2c1.Init.Timing           = 100000;
  hi2c1.Init.OwnAddress1      = 0;
  hi2c1.Init.AddressingMode   = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode  = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2      = 0;
  hi2c1.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c1.Init.GeneralCallMode  = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode    = I2C_NOSTRETCH_DISABLE;

  __HAL_RCC_I2C1_FORCE_RESET();
	__HAL_RCC_I2C1_RELEASE_RESET();
  HAL_I2C_DeInit(&hi2c1);
  if (HAL_I2C_Init(&hi2c1) != HAL_OK){Error_Handler();}

}

static void UART_Init(void)
{
  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();}
}

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;
}

void OLED_Write_Byte(uint8_t cmd,uint8_t data){
    printf("Writting:%02x,%02x\n",cmd,data);
    
		HAL_I2C_Mem_Write(&hi2c1,(uint16_t)(0x3c<<1),cmd,I2C_MEMADD_SIZE_8BIT,&data,1,HAL_MAX_DELAY);
}

static void OLED_SetVerticalPos(uint8_t x, uint8_t up, uint8_t down) {
		uint8_t CmdReg=0x00;
    OLED_Write_Byte(CmdReg, 0x22);  
    OLED_Write_Byte(CmdReg, up);    
    OLED_Write_Byte(CmdReg, down);  
    OLED_Write_Byte(CmdReg, 0x21);  
    OLED_Write_Byte(CmdReg, x);     
    OLED_Write_Byte(CmdReg, 0x7f);  
}
void OLED_SetPos(uint8_t x, uint8_t page) {
    OLED_SetVerticalPos(x, page, 0x07);
}
void OLED_Fill(uint8_t data){
    uint16_t i;
    OLED_SetPos(0, 0);
		uint8_t DataReg = 0x40;
    for (i = 0; i < 8 * OLED_Width; i++) OLED_Write_Byte(DataReg, data);

    memset(OLED_buffer, data, sizeof(OLED_buffer));
    memset(OLED_buffer_flag, 0, sizeof(OLED_buffer_flag));
}

void LCD_Init(){
		uint8_t CmdReg=0x00;
		 OLED_Write_Byte(CmdReg, 0xae);  
    OLED_Write_Byte(CmdReg, 0x20);  
    OLED_Write_Byte(CmdReg, 0x01);
    OLED_Write_Byte(CmdReg, 0x81);  
    OLED_Write_Byte(CmdReg, 0xff);  
    OLED_Write_Byte(CmdReg, 0xc8);  
    OLED_Write_Byte(CmdReg, 0xa1);  
    OLED_Write_Byte(CmdReg, 0xa8);  
    OLED_Write_Byte(CmdReg, 0x3f);  
    OLED_Write_Byte(CmdReg, 0xd3);  
    OLED_Write_Byte(CmdReg, 0x00);  
    OLED_Write_Byte(CmdReg, 0xd5);  
    OLED_Write_Byte(CmdReg, 0x80);  
    OLED_Write_Byte(CmdReg, 0xd8);  
    OLED_Write_Byte(CmdReg, 0x05);  
    OLED_Write_Byte(CmdReg, 0xd9); 
    OLED_Write_Byte(CmdReg, 0xf1);  
    OLED_Write_Byte(CmdReg, 0xda);  
    OLED_Write_Byte(CmdReg, 0x12);  
    OLED_Write_Byte(CmdReg, 0xdb);  
    OLED_Write_Byte(CmdReg, 0x30);  
    OLED_Write_Byte(CmdReg, 0x8d);  
    OLED_Write_Byte(CmdReg, 0x14);  
    OLED_Write_Byte(CmdReg, 0xa4);  
    OLED_Write_Byte(CmdReg, 0xa6);  
    OLED_Fill(0x0f);                    
    OLED_Write_Byte(CmdReg, 0xaf);
    
}

void Error_Handler(void)
{

}